diff --git a/Gopkg.lock b/Gopkg.lock
index e4ffbafe80..2785b25d27 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -1,6 +1,14 @@
 # This file is autogenerated, do not edit; changes may be undone by the next 'dep ensure'.
 
 
+[[projects]]
+  branch = "master"
+  digest = "1:d6afaeed1502aa28e80a4ed0981d570ad91b2579193404256ce672ed0a609e0d"
+  name = "github.com/beorn7/perks"
+  packages = ["quantile"]
+  pruneopts = "UT"
+  revision = "3a771d992973f24aa725d07868b467d1ddfceafb"
+
 [[projects]]
   digest = "1:6b21090f60571b20b3ddc2c8e48547dffcf409498ed6002c2cada023725ed377"
   name = "github.com/davecgh/go-spew"
@@ -40,7 +48,7 @@
   revision = "02826c3e79038b59d737d3b1c0a1d937f71a4433"
 
 [[projects]]
-  digest = "1:8f2df6167daef6f4d56d07f99bbcf4733117db0dedfd959995b9a679c52561f1"
+  digest = "1:239c4c7fd2159585454003d9be7207167970194216193a8a210b8d29576f19c9"
   name = "github.com/golang/protobuf"
   packages = [
     "proto",
@@ -50,7 +58,8 @@
     "ptypes/timestamp",
   ]
   pruneopts = "UT"
-  revision = "1643683e1b54a9e88ad26d98f81400c8c9d9f4f9"
+  revision = "c823c79ea1570fb5ff454033735a8e68575d1d0f"
+  version = "v1.3.0"
 
 [[projects]]
   branch = "master"
@@ -115,6 +124,14 @@
   revision = "1624edc4454b8682399def8740d46db5e4362ba4"
   version = "v1.1.5"
 
+[[projects]]
+  digest = "1:ff5ebae34cfbf047d505ee150de27e60570e8c394b3b8fdbb720ff6ac71985fc"
+  name = "github.com/matttproud/golang_protobuf_extensions"
+  packages = ["pbutil"]
+  pruneopts = "UT"
+  revision = "c12348ce28de40eed0136aa2b644d0ee0650e56c"
+  version = "v1.0.1"
+
 [[projects]]
   digest = "1:33422d238f147d247752996a26574ac48dcf472976eda7f5134015f06bf16563"
   name = "github.com/modern-go/concurrent"
@@ -139,6 +156,17 @@
   revision = "47154e1ef11536726753d5f506babe9304d622d2"
   version = "v0.2"
 
+[[projects]]
+  digest = "1:aeb11030e3ed0339cfb28f20ee23219e73202f8f8b589f1547c56d6a6a4e36e9"
+  name = "github.com/nginxinc/nginx-prometheus-exporter"
+  packages = [
+    "client",
+    "collector",
+  ]
+  pruneopts = "UT"
+  revision = "65702758f28e7f472fa3a978d9321ee3cb9a7d2c"
+  version = "v0.3.0"
+
 [[projects]]
   branch = "master"
   digest = "1:3bf17a6e6eaa6ad24152148a631d18662f7212e21637c2699bff3369b7f00fa2"
@@ -155,6 +183,52 @@
   revision = "5f041e8faa004a95c88a202771f4cc3e991971e6"
   version = "v2.0.1"
 
+[[projects]]
+  digest = "1:93a746f1060a8acbcf69344862b2ceced80f854170e1caae089b2834c5fbf7f4"
+  name = "github.com/prometheus/client_golang"
+  packages = [
+    "prometheus",
+    "prometheus/internal",
+    "prometheus/promhttp",
+  ]
+  pruneopts = "UT"
+  revision = "505eaef017263e299324067d40ca2c48f6a2cf50"
+  version = "v0.9.2"
+
+[[projects]]
+  branch = "master"
+  digest = "1:2d5cd61daa5565187e1d96bae64dbbc6080dacf741448e9629c64fd93203b0d4"
+  name = "github.com/prometheus/client_model"
+  packages = ["go"]
+  pruneopts = "UT"
+  revision = "fd36f4220a901265f90734c3183c5f0c91daa0b8"
+
+[[projects]]
+  digest = "1:35cf6bdf68db765988baa9c4f10cc5d7dda1126a54bd62e252dbcd0b1fc8da90"
+  name = "github.com/prometheus/common"
+  packages = [
+    "expfmt",
+    "internal/bitbucket.org/ww/goautoneg",
+    "model",
+  ]
+  pruneopts = "UT"
+  revision = "cfeb6f9992ffa54aaa4f2170ade4067ee478b250"
+  version = "v0.2.0"
+
+[[projects]]
+  branch = "master"
+  digest = "1:ca30ee2c96d195cef49b546d10825d3e13b50c63da4df23c80e77c51e07bad0d"
+  name = "github.com/prometheus/procfs"
+  packages = [
+    ".",
+    "internal/util",
+    "iostats",
+    "nfs",
+    "xfs",
+  ]
+  pruneopts = "UT"
+  revision = "6ed1f7e1041181781dd2826d3001075d011a80cc"
+
 [[projects]]
   digest = "1:b7386dc2acd6ae7a2383c7e35edf894b73df06338c04c49df3887087d2a97bab"
   name = "github.com/spf13/pflag"
@@ -468,6 +542,10 @@
   input-imports = [
     "github.com/golang/glog",
     "github.com/nginxinc/nginx-plus-go-sdk/client",
+    "github.com/nginxinc/nginx-prometheus-exporter/client",
+    "github.com/nginxinc/nginx-prometheus-exporter/collector",
+    "github.com/prometheus/client_golang/prometheus",
+    "github.com/prometheus/client_golang/prometheus/promhttp",
     "k8s.io/api/core/v1",
     "k8s.io/api/extensions/v1beta1",
     "k8s.io/apimachinery/pkg/apis/meta/v1",
diff --git a/Gopkg.toml b/Gopkg.toml
index 2145a44d6e..1a2678c1df 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -17,3 +17,16 @@
 [[constraint]]
   name = "github.com/nginxinc/nginx-plus-go-sdk"
   version = "0.2.0"
+  
+[[constraint]]
+  name = "github.com/prometheus/client_golang"
+  version = "0.9.2"
+
+[[constraint]]
+  name = "github.com/nginxinc/nginx-prometheus-exporter"
+  version = "0.3.0"
+
+# github.com/prometheus/client_golang "0.9.2" requires github.com/golang/protobuf "1.3.0"
+[[override]]
+  name = "github.com/golang/protobuf"
+  version = "1.3.0"
\ No newline at end of file
diff --git a/cmd/nginx-ingress/main.go b/cmd/nginx-ingress/main.go
index ab4239d32c..0d6aaf4f68 100644
--- a/cmd/nginx-ingress/main.go
+++ b/cmd/nginx-ingress/main.go
@@ -15,6 +15,7 @@ import (
 	"github.com/golang/glog"
 	"github.com/nginxinc/kubernetes-ingress/internal/controller"
 	"github.com/nginxinc/kubernetes-ingress/internal/handlers"
+	"github.com/nginxinc/kubernetes-ingress/internal/metrics"
 	"github.com/nginxinc/kubernetes-ingress/internal/nginx"
 	"github.com/nginxinc/kubernetes-ingress/internal/nginx/plus"
 	"github.com/nginxinc/kubernetes-ingress/internal/utils"
@@ -98,6 +99,12 @@ The external address of the service is used when reporting the status of Ingress
 		`A Secret with a TLS certificate and key for TLS termination of every Ingress host for which TLS termination is enabled but the Secret is not specified. 
 		Format: <namespace>/<name>. If the argument is not set, for such Ingress hosts NGINX will break any attempt to establish a TLS connection. 
 		If the argument is set, but the Ingress controller is not able to fetch the Secret from Kubernetes API, the Ingress controller will fail to start.`)
+
+	enablePrometheusMetrics = flag.Bool("enable-prometheus-metrics", false,
+		"Enable exposing NGINX or NGINX Plus metrics in the Prometheus format")
+
+	prometheusMetricsListenPort = flag.Int("prometheus-metrics-listen-port", 9113,
+		"Set the port where the Prometheus metrics are exposed. [1023 - 65535]")
 )
 
 func main() {
@@ -109,9 +116,14 @@ func main() {
 		os.Exit(0)
 	}
 
-	portValidationError := validateStatusPort(*nginxStatusPort)
-	if portValidationError != nil {
-		glog.Fatalf("Invalid value for nginx-status-port: %v", portValidationError)
+	statusPortValidationError := validatePort(*nginxStatusPort)
+	if statusPortValidationError != nil {
+		glog.Fatalf("Invalid value for nginx-status-port: %v", statusPortValidationError)
+	}
+
+	metricsPortValidationError := validatePort(*prometheusMetricsListenPort)
+	if metricsPortValidationError != nil {
+		glog.Fatalf("Invalid value for prometheus-metrics-listen-port: %v", metricsPortValidationError)
 	}
 
 	var err error
@@ -166,7 +178,7 @@ func main() {
 		nginxBinaryPath = "/usr/sbin/nginx-debug"
 	}
 
-	templateExecutor, err := nginx.NewTemplateExecutor(nginxConfTemplatePath, nginxIngressTemplatePath, *healthStatus, *nginxStatus, allowedCIDRs, *nginxStatusPort)
+	templateExecutor, err := nginx.NewTemplateExecutor(nginxConfTemplatePath, nginxIngressTemplatePath, *healthStatus, *nginxStatus, allowedCIDRs, *nginxStatusPort, *enablePrometheusMetrics)
 	if err != nil {
 		glog.Fatalf("Error creating TemplateExecutor: %v", err)
 	}
@@ -243,7 +255,7 @@ func main() {
 
 	var nginxAPI *plus.NginxAPIController
 	if *nginxPlus {
-		httpClient := getSocketClient()
+		httpClient := getSocketClient("/var/run/nginx-plus-api.sock")
 		nginxAPI, err = plus.NewNginxAPIController(&httpClient, "http://nginx-plus-api/api", local)
 		if err != nil {
 			glog.Fatalf("Failed to create NginxAPIController: %v", err)
@@ -298,6 +310,19 @@ func main() {
 		lbc.AddLeaderHandler(leaderHandler)
 	}
 
+	if *enablePrometheusMetrics {
+		if *nginxPlus {
+			go metrics.RunPrometheusListenerForNginxPlus(*prometheusMetricsListenPort, nginxAPI.GetClientPlus())
+		} else {
+			httpClient := getSocketClient("/var/run/nginx-status.sock")
+			client, err := metrics.NewNginxMetricsClient(&httpClient)
+			if err != nil {
+				glog.Fatalf("Error creating the Nginx client for Prometheus metrics: %v", err)
+			}
+			go metrics.RunPrometheusListenerForNginx(*prometheusMetricsListenPort, client)
+		}
+	}
+
 	go handleTermination(lbc, ngxc, nginxDone)
 	lbc.Run()
 
@@ -341,19 +366,20 @@ func handleTermination(lbc *controller.LoadBalancerController, ngxc *nginx.Contr
 }
 
 // getSocketClient gets an http.Client with the a unix socket transport.
-func getSocketClient() http.Client {
+func getSocketClient(sockPath string) http.Client {
 	return http.Client{
 		Transport: &http.Transport{
 			DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
-				return net.Dial("unix", "/var/run/nginx-plus-api.sock")
+				return net.Dial("unix", sockPath)
 			},
 		},
 	}
 }
 
-func validateStatusPort(nginxStatusPort int) error {
-	if nginxStatusPort < 1023 || nginxStatusPort > 65535 {
-		return fmt.Errorf("port outside of valid port range [1023 - 65535]: %v", nginxStatusPort)
+// validatePort makes sure a given port is inside the valid port range for its usage
+func validatePort(port int) error {
+	if port < 1023 || port > 65535 {
+		return fmt.Errorf("port outside of valid port range [1023 - 65535]: %v", port)
 	}
 	return nil
 }
diff --git a/cmd/nginx-ingress/main_test.go b/cmd/nginx-ingress/main_test.go
index 2a308198a1..a601da4d89 100644
--- a/cmd/nginx-ingress/main_test.go
+++ b/cmd/nginx-ingress/main_test.go
@@ -6,10 +6,10 @@ import (
 	"testing"
 )
 
-func TestValidateStatusPort(t *testing.T) {
+func TestValidatePort(t *testing.T) {
 	badPorts := []int{80, 443, 1, 1022, 65536}
 	for _, badPort := range badPorts {
-		err := validateStatusPort(badPort)
+		err := validatePort(badPort)
 		if err == nil {
 			t.Errorf("Expected error for port %v\n", badPort)
 		}
@@ -17,7 +17,7 @@ func TestValidateStatusPort(t *testing.T) {
 
 	goodPorts := []int{8080, 8081, 8082, 1023, 65535}
 	for _, goodPort := range goodPorts {
-		err := validateStatusPort(goodPort)
+		err := validatePort(goodPort)
 		if err != nil {
 			t.Errorf("Error for valid port:  %v err: %v\n", goodPort, err)
 		}
diff --git a/deployments/daemon-set/nginx-ingress-with-prometheus.yaml b/deployments/daemon-set/nginx-ingress-with-prometheus.yaml
deleted file mode 100644
index d20b9bcd8e..0000000000
--- a/deployments/daemon-set/nginx-ingress-with-prometheus.yaml
+++ /dev/null
@@ -1,54 +0,0 @@
-apiVersion: extensions/v1beta1
-kind: DaemonSet
-metadata:
-  name: nginx-ingress
-  namespace: nginx-ingress
-spec:
-  selector:
-    matchLabels:
-      app: nginx-ingress
-  template:
-    metadata:
-      labels:
-        app: nginx-ingress
-      annotations:
-        prometheus.io/scrape: "true"
-        prometheus.io/port: "9113"
-    spec:
-      serviceAccountName: nginx-ingress
-      containers:
-      - image: nginx/nginx-ingress:edge
-        name: nginx-ingress
-        ports:
-        - name: http
-          containerPort: 80
-          hostPort: 80
-        - name: https
-          containerPort: 443
-          hostPort: 443
-        env:
-        - name: POD_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
-        - name: POD_NAME
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.name
-        args:
-          - -nginx-configmaps=$(POD_NAMESPACE)/nginx-config
-          - -default-server-tls-secret=$(POD_NAMESPACE)/default-server-secret
-         #- -v=3 # Enables extensive logging. Useful for troubleshooting.
-         #- -report-ingress-status
-         #- -external-service=nginx-ingress
-         #- -enable-leader-election
-      - image: nginx/nginx-prometheus-exporter:0.2.0
-        name: nginx-prometheus-exporter
-        ports:
-        - name: prometheus
-          containerPort: 9113
-        args:
-          - -web.listen-address
-          - :9113
-          - -nginx.scrape-uri
-          - http://127.0.0.1:8080/stub_status
diff --git a/deployments/daemon-set/nginx-ingress.yaml b/deployments/daemon-set/nginx-ingress.yaml
index 8c33fdba08..0c47167ee1 100644
--- a/deployments/daemon-set/nginx-ingress.yaml
+++ b/deployments/daemon-set/nginx-ingress.yaml
@@ -11,6 +11,9 @@ spec:
     metadata:
       labels:
         app: nginx-ingress
+     #annotations:
+       #prometheus.io/scrape: "true"
+       #prometheus.io/port: 9113
     spec:
       serviceAccountName: nginx-ingress
       containers:
@@ -24,6 +27,8 @@ spec:
         - name: https
           containerPort: 443
           hostPort: 443
+       #- name: prometheus
+         #containerPort: 9113
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -40,3 +45,4 @@ spec:
          #- -report-ingress-status
          #- -external-service=nginx-ingress
          #- -enable-leader-election
+         #- -enable-prometheus-metrics
diff --git a/deployments/daemon-set/nginx-plus-ingress-with-prometheus.yaml b/deployments/daemon-set/nginx-plus-ingress-with-prometheus.yaml
deleted file mode 100644
index c0b77b44bd..0000000000
--- a/deployments/daemon-set/nginx-plus-ingress-with-prometheus.yaml
+++ /dev/null
@@ -1,57 +0,0 @@
-apiVersion: extensions/v1beta1
-kind: DaemonSet
-metadata:
-  name: nginx-ingress
-  namespace: nginx-ingress
-spec:
-  selector:
-    matchLabels:
-      app: nginx-ingress
-  template:
-    metadata:
-      labels:
-        app: nginx-ingress
-      annotations:
-        prometheus.io/scrape: "true"
-        prometheus.io/port: "9113"
-    spec:
-      serviceAccountName: nginx-ingress
-      containers:
-      - image: nginx-plus-ingress:edge
-        imagePullPolicy: Always
-        name: nginx-plus-ingress
-        ports:
-        - name: http
-          containerPort: 80
-          hostPort: 80
-        - name: https
-          containerPort: 443
-          hostPort: 443
-        env:
-        - name: POD_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
-        - name: POD_NAME
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.name
-        args:
-          - -nginx-plus
-          - -nginx-configmaps=$(POD_NAMESPACE)/nginx-config
-          - -default-server-tls-secret=$(POD_NAMESPACE)/default-server-secret
-         #- -v=3 # Enables extensive logging. Useful for troubleshooting.
-         #- -report-ingress-status
-         #- -external-service=nginx-ingress
-         #- -enable-leader-election
-      - image: nginx/nginx-prometheus-exporter:0.2.0
-        name: nginx-prometheus-exporter
-        ports:
-        - name: prometheus
-          containerPort: 9113
-        args:
-          - -web.listen-address
-          - :9113
-          - -nginx.plus
-          - -nginx.scrape-uri
-          - http://127.0.0.1:8080/api
diff --git a/deployments/daemon-set/nginx-plus-ingress.yaml b/deployments/daemon-set/nginx-plus-ingress.yaml
index 0773cc5155..a8f9840691 100644
--- a/deployments/daemon-set/nginx-plus-ingress.yaml
+++ b/deployments/daemon-set/nginx-plus-ingress.yaml
@@ -11,6 +11,9 @@ spec:
     metadata:
       labels:
         app: nginx-ingress
+     #annotations:
+       #prometheus.io/scrape: "true"
+       #prometheus.io/port: 9113
     spec:
       serviceAccountName: nginx-ingress
       containers:
@@ -24,6 +27,8 @@ spec:
         - name: https
           containerPort: 443
           hostPort: 443
+       #- name: prometheus
+         #containerPort: 9113
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -41,3 +46,4 @@ spec:
          #- -report-ingress-status
          #- -external-service=nginx-ingress
          #- -enable-leader-election
+         #- -enable-prometheus-metrics
diff --git a/deployments/deployment/nginx-ingress-with-prometheus.yaml b/deployments/deployment/nginx-ingress-with-prometheus.yaml
deleted file mode 100644
index b9b762a58f..0000000000
--- a/deployments/deployment/nginx-ingress-with-prometheus.yaml
+++ /dev/null
@@ -1,53 +0,0 @@
-apiVersion: extensions/v1beta1
-kind: Deployment
-metadata:
-  name: nginx-ingress
-  namespace: nginx-ingress
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      app: nginx-ingress
-  template:
-    metadata:
-      labels:
-        app: nginx-ingress
-      annotations:
-        prometheus.io/scrape: "true"
-        prometheus.io/port: "9113"
-    spec:
-      serviceAccountName: nginx-ingress
-      containers:
-      - image: nginx/nginx-ingress:edge
-        name: nginx-ingress
-        ports:
-        - name: http
-          containerPort: 80
-        - name: https
-          containerPort: 443
-        env:
-        - name: POD_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
-        - name: POD_NAME
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.name
-        args:
-          - -nginx-configmaps=$(POD_NAMESPACE)/nginx-config
-          - -default-server-tls-secret=$(POD_NAMESPACE)/default-server-secret
-         #- -v=3 # Enables extensive logging. Useful for troubleshooting.
-         #- -report-ingress-status
-         #- -external-service=nginx-ingress
-         #- -enable-leader-election
-      - image: nginx/nginx-prometheus-exporter:0.2.0
-        name: nginx-prometheus-exporter
-        ports:
-        - name: prometheus
-          containerPort: 9113
-        args:
-          - -web.listen-address
-          - :9113
-          - -nginx.scrape-uri
-          - http://127.0.0.1:8080/stub_status
diff --git a/deployments/deployment/nginx-ingress.yaml b/deployments/deployment/nginx-ingress.yaml
index 81771ccbbc..65084a42ed 100644
--- a/deployments/deployment/nginx-ingress.yaml
+++ b/deployments/deployment/nginx-ingress.yaml
@@ -12,6 +12,9 @@ spec:
     metadata:
       labels:
         app: nginx-ingress
+     #annotations:
+       #prometheus.io/scrape: "true"
+       #prometheus.io/port: 9113
     spec:
       serviceAccountName: nginx-ingress
       containers:
@@ -23,6 +26,8 @@ spec:
           containerPort: 80
         - name: https
           containerPort: 443
+       #- name: prometheus
+         #containerPort: 9113
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -39,3 +44,4 @@ spec:
          #- -report-ingress-status
          #- -external-service=nginx-ingress
          #- -enable-leader-election
+         #- -enable-prometheus-metrics
diff --git a/deployments/deployment/nginx-plus-ingress-with-prometheus.yaml b/deployments/deployment/nginx-plus-ingress-with-prometheus.yaml
deleted file mode 100644
index d385a10c0d..0000000000
--- a/deployments/deployment/nginx-plus-ingress-with-prometheus.yaml
+++ /dev/null
@@ -1,56 +0,0 @@
-apiVersion: extensions/v1beta1
-kind: Deployment
-metadata:
-  name: nginx-ingress
-  namespace: nginx-ingress
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      app: nginx-ingress
-  template:
-    metadata:
-      labels:
-        app: nginx-ingress
-      annotations:
-        prometheus.io/scrape: "true"
-        prometheus.io/port: "9113"
-    spec:
-      serviceAccountName: nginx-ingress
-      containers:
-      - image: nginx-plus-ingress:edge
-        imagePullPolicy: Always
-        name: nginx-plus-ingress
-        ports:
-        - name: http
-          containerPort: 80
-        - name: https
-          containerPort: 443
-        env:
-        - name: POD_NAMESPACE
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.namespace
-        - name: POD_NAME
-          valueFrom:
-            fieldRef:
-              fieldPath: metadata.name
-        args:
-          - -nginx-plus
-          - -nginx-configmaps=$(POD_NAMESPACE)/nginx-config
-          - -default-server-tls-secret=$(POD_NAMESPACE)/default-server-secret
-         #- -v=3 # Enables extensive logging. Useful for troubleshooting.
-         #- -report-ingress-status
-         #- -external-service=nginx-ingress
-         #- -enable-leader-election
-      - image: nginx/nginx-prometheus-exporter:0.2.0
-        name: nginx-prometheus-exporter
-        ports:
-        - name: prometheus
-          containerPort: 9113
-        args:
-          - -web.listen-address
-          - :9113
-          - -nginx.plus
-          - -nginx.scrape-uri
-          - http://127.0.0.1:8080/api
diff --git a/deployments/deployment/nginx-plus-ingress.yaml b/deployments/deployment/nginx-plus-ingress.yaml
index 53d44dee34..bf19aae39b 100644
--- a/deployments/deployment/nginx-plus-ingress.yaml
+++ b/deployments/deployment/nginx-plus-ingress.yaml
@@ -12,6 +12,9 @@ spec:
     metadata:
       labels:
         app: nginx-ingress
+     #annotations:
+       #prometheus.io/scrape: "true"
+       #prometheus.io/port: 9113
     spec:
       serviceAccountName: nginx-ingress
       containers:
@@ -23,6 +26,8 @@ spec:
           containerPort: 80
         - name: https
           containerPort: 443
+       #- name: prometheus
+         #containerPort: 9113
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -40,3 +45,4 @@ spec:
          #- -report-ingress-status
          #- -external-service=nginx-ingress
          #- -enable-leader-election
+         #- -enable-prometheus-metrics
diff --git a/deployments/helm-chart/README.md b/deployments/helm-chart/README.md
index 6371b15f35..15867f282a 100644
--- a/deployments/helm-chart/README.md
+++ b/deployments/helm-chart/README.md
@@ -103,11 +103,9 @@ Parameter | Description | Default
 `controller.reportIngressStatus.externalService` | Specifies the name of the service with the type LoadBalancer through which the Ingress controller is exposed externally. The external address of the service is used when reporting the status of Ingress resources. `controller.reportIngressStatus.enable` must be set to `true`. | nginx-ingress
 `controller.reportIngressStatus.enableLeaderElection` | Enable Leader election to avoid multiple replicas of the controller reporting the status of Ingress resources. `controller.reportIngressStatus.enable` must be set to `true`. | true
 `rbac.create` | Configures RBAC. | true
-`prometheues.create` | Deploys a Prometheus exporter container within the Ingress controller pod. Requires NGINX status enabled via `controller.nginxStatus.enable`. Note: the exporter will use the port specified by `controller.nginxStatus.port`.| false
+`prometheus.create` | Expose NGINX or NGINX Plus metrics in the Prometheus format. | false
 `prometheus.port` | Configures the port to scrape the metrics. | 9113
-`prometheus.image.repository` | The image repository of the Prometheus exporter. | nginx/nginx-prometheus-exporter
-`prometheus.image.tag` | The tag of the Prometheus exporter image. | 0.2.0
-`prometheus.image.pullPolicy` | The pull policy for the Prometheus exporter image. | IfNotPresent
+
 
 Example:
 ```console
diff --git a/deployments/helm-chart/templates/controller-daemonset.yaml b/deployments/helm-chart/templates/controller-daemonset.yaml
index 0d33b36a16..3f506b8804 100644
--- a/deployments/helm-chart/templates/controller-daemonset.yaml
+++ b/deployments/helm-chart/templates/controller-daemonset.yaml
@@ -45,6 +45,10 @@ spec:
         - name: https
           containerPort: 443
           hostPort: 443
+{{- if .Values.prometheus.create }}
+        - name: prometheus
+          containerPort: {{ .Values.prometheus.port }}
+{{- end }}
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -84,23 +88,6 @@ spec:
 {{- else if and .Values.controller.wildcardTLS.cert .Values.controller.wildcardTLS.key }}
           - -wildcard-tls-secret=$(POD_NAMESPACE)/wildcard-tls-secret
 {{- end }}
-{{- if and .Values.prometheus.create .Values.controller.nginxStatus.enable }}
-      - image: "{{ .Values.prometheus.image.repository }}:{{ .Values.prometheus.image.tag }}"
-        name: nginx-prometheus-exporter
-        imagePullPolicy: "{{ .Values.prometheus.image.pullPolicy }}"
-        ports:
-        - name: prometheus
-          containerPort: {{ .Values.prometheus.port }}
-        args:
-          - -web.listen-address
-          - :{{ .Values.prometheus.port }}
-{{- if .Values.controller.nginxplus }}
-          - -nginx.plus
-          - -nginx.scrape-uri
-          - http://127.0.0.1:{{ .Values.controller.nginxStatus.port }}/api
-{{ else }}
-          - -nginx.scrape-uri
-          - http://127.0.0.1:{{ .Values.controller.nginxStatus.port }}/stub_status
-{{- end }}
-{{- end }}
-{{- end }}
+          - -enable-prometheus-metrics={{ .Values.prometheus.create }}
+          - -prometheus-metrics-listen-port={{ .Values.prometheus.port }}
+{{- end }}
\ No newline at end of file
diff --git a/deployments/helm-chart/templates/controller-deployment.yaml b/deployments/helm-chart/templates/controller-deployment.yaml
index 1acb08d91e..674ce92f1a 100644
--- a/deployments/helm-chart/templates/controller-deployment.yaml
+++ b/deployments/helm-chart/templates/controller-deployment.yaml
@@ -43,6 +43,10 @@ spec:
           containerPort: 80
         - name: https
           containerPort: 443
+{{- if .Values.prometheus.create }}
+        - name: prometheus
+          containerPort: {{ .Values.prometheus.port }}
+{{- end }}
         env:
         - name: POD_NAMESPACE
           valueFrom:
@@ -82,23 +86,6 @@ spec:
 {{- else if and .Values.controller.wildcardTLS.cert .Values.controller.wildcardTLS.key }}
           - -wildcard-tls-secret=$(POD_NAMESPACE)/wildcard-tls-secret
 {{- end }}
-{{- if and .Values.prometheus.create .Values.controller.nginxStatus.enable }}
-      - image: "{{ .Values.prometheus.image.repository }}:{{ .Values.prometheus.image.tag }}"
-        name: nginx-prometheus-exporter
-        imagePullPolicy: "{{ .Values.prometheus.image.pullPolicy }}"
-        ports:
-        - name: prometheus
-          containerPort: {{ .Values.prometheus.port }}
-        args:
-          - -web.listen-address
-          - :{{ .Values.prometheus.port }}
-{{- if .Values.controller.nginxplus }}
-          - -nginx.plus
-          - -nginx.scrape-uri
-          - http://127.0.0.1:{{ .Values.controller.nginxStatus.port }}/api
-{{ else }}
-          - -nginx.scrape-uri
-          - http://127.0.0.1:{{ .Values.controller.nginxStatus.port }}/stub_status
-{{- end }}
-{{- end }}
-{{- end }}
+          - -enable-prometheus-metrics={{ .Values.prometheus.create }}
+          - -prometheus-metrics-listen-port={{ .Values.prometheus.port }}
+{{- end }}
\ No newline at end of file
diff --git a/deployments/helm-chart/values.yaml b/deployments/helm-chart/values.yaml
index 55b0c97adc..432fcbcf13 100644
--- a/deployments/helm-chart/values.yaml
+++ b/deployments/helm-chart/values.yaml
@@ -160,19 +160,8 @@ rbac:
   create: true
 
 prometheus:
-  ## Deploys a Prometheus exporter container within the Ingress controller pod. Requires NGINX status enabled via controller.nginxStatus.enable.
-  ## Note: the exporter will use the port specified by controller.nginxStatus.port.
-  create: false
+  ## Expose NGINX or NGINX Plus metrics in the Prometheus format.
+  create: true
 
   ## Configures the port to scrape the metrics.
-  port: 9113
-
-  image:
-    ## The image repository of the Prometheus exporter.
-    repository: nginx/nginx-prometheus-exporter
-
-    ## The tag of the Prometheus exporter image.
-    tag: "0.2.0"
-
-    ## The pull policy for the Prometheus exporter image.
-    pullPolicy: IfNotPresent
+  port: 9113
\ No newline at end of file
diff --git a/docs/cli-arguments.md b/docs/cli-arguments.md
index c37aa0de50..8303af3e6f 100644
--- a/docs/cli-arguments.md
+++ b/docs/cli-arguments.md
@@ -69,4 +69,8 @@ Usage of ./nginx-ingress:
     	comma-separated list of pattern=N settings for file-filtered logging
   -watch-namespace string
     	Namespace to watch for Ingress resources. By default the Ingress controller watches all namespaces
+  -enable-prometheus-metrics
+    	Enable exposing NGINX or NGINX Plus metrics in the Prometheus format
+  -prometheus-metrics-listen-port
+    	Set the port where the Prometheus metrics are exposed. [1023 - 65535] (default 9113)
 ```
diff --git a/docs/installation.md b/docs/installation.md
index a2aeff596e..a16fdf792c 100644
--- a/docs/installation.md
+++ b/docs/installation.md
@@ -146,7 +146,7 @@ Read more about the type LoadBalancer [here](https://kubernetes.io/docs/concepts
 ## 5. Access the Live Activity Monitoring Dashboard / Stub_status Page
 For NGINX, you can access the [stub_status page](http://nginx.org/en/docs/http/ngx_http_stub_status_module.html):
 1. Stub_status is enabled by default. Ensure that the `nginx-status` command-line argument is not set to false.
-2. Stub_status is available on port 8080 by default. It is customizable by the `nginx-status-port` command-line argument. If yours is not on 8080, modify the kubectl proxy command below.
+1. Stub_status is available on port 8080 by default. It is customizable by the `nginx-status-port` command-line argument. If yours is not on 8080, modify the kubectl proxy command below.
 1. Use the `kubectl port-forward` command to forward connections to port 8080 on your local machine to port 8080 of an NGINX Ingress controller pod (replace `<nginx-ingress-pod>` with the actual name of a pod):.
     ```
     $ kubectl port-forward <nginx-ingress-pod> 8080:8080 --namespace=nginx-ingress
@@ -165,26 +165,19 @@ For NGINX Plus, you can access the live activity monitoring dashboard:
 
 ## Support For Prometheus Monitoring
 
-If you are using [Prometheus](https://prometheus.io/), you can deploy the NGINX Ingress controller with the [Prometheus exporter](https://github.com/nginxinc/nginx-prometheus-exporter) for NGINX. The exporter will export NGINX metrics into your Prometheus.
+You can expose NGINX or NGINX Plus metrics for collection by [Prometheus](https://prometheus.io/):
 
-To deploy the NGINX Ingress controller with the exporter, use the modified manifests:
-* For a deployment, run:
+1. Run the Ingress controller with the `-enable-prometheus-metrics` [command-line argument](cli-arguments.md). As a result, the Ingress Controller will expose NGINX or NGINX Plus metrics in the Prometheus format via the path `/metrics` on port `9113` (customizable via the `-prometheus-metrics-listen-port` command-line argument).
+1. Add the Prometheus port to the list of the ports of the Ingress Controller container:
+    ```yaml
+    - name: prometheus
+      containerPort: 9113
     ```
-    $ kubectl apply -f deployment/nginx-ingress-with-prometheus.yaml
-    ```
-* For a daemonset, run:
-    ```
-    $ kubectl apply -f daemon-set/nginx-ingress-with-prometheus.yaml
-    ```
-
-To deploy the NGINX Plus Ingress controller with the exporter, use the modified manifests:
-* For a deployment, run:
-    ```
-    $ kubectl apply -f deployment/nginx-plus-ingress-with-prometheus.yaml
-    ```
-* For a daemon set, run:
-    ```
-    $ kubectl apply -f daemon-set/nginx-plus-ingress-with-prometheus.yaml
+1. Make the Prometheus aware of the Ingress Controller targets by adding the following annotations to the template of the Ingress Controller pod (note: this assumes your Prometheus is configured to discover targets by analyzing the annotations of pods):
+    ```yaml
+    annotations:
+        prometheus.io/scrape: "true"
+        prometheus.io/port: 9113
     ```
 
 ## Uninstall the Ingress Controller
diff --git a/internal/controller/controller_test.go b/internal/controller/controller_test.go
index f992910a9a..fb8131e9f2 100644
--- a/internal/controller/controller_test.go
+++ b/internal/controller/controller_test.go
@@ -926,7 +926,7 @@ func TestFindIngressesForSecret(t *testing.T) {
 		t.Run(test.desc, func(t *testing.T) {
 			fakeClient := fake.NewSimpleClientset()
 
-			templateExecutor, err := nginx.NewTemplateExecutor("../nginx/templates/nginx-plus.tmpl", "../nginx/templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080)
+			templateExecutor, err := nginx.NewTemplateExecutor("../nginx/templates/nginx-plus.tmpl", "../nginx/templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080, false)
 			if err != nil {
 				t.Fatalf("templateExecuter could not start: %v", err)
 			}
@@ -1107,7 +1107,7 @@ func TestFindIngressesForSecretWithMinions(t *testing.T) {
 		t.Run(test.desc, func(t *testing.T) {
 			fakeClient := fake.NewSimpleClientset()
 
-			templateExecutor, err := nginx.NewTemplateExecutor("../nginx/templates/nginx-plus.tmpl", "../nginx/templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080)
+			templateExecutor, err := nginx.NewTemplateExecutor("../nginx/templates/nginx-plus.tmpl", "../nginx/templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080, false)
 			if err != nil {
 				t.Fatalf("templateExecuter could not start: %v", err)
 			}
diff --git a/internal/metrics/prometheus.go b/internal/metrics/prometheus.go
new file mode 100644
index 0000000000..bc33dabab1
--- /dev/null
+++ b/internal/metrics/prometheus.go
@@ -0,0 +1,53 @@
+package metrics
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/golang/glog"
+	sdkClient "github.com/nginxinc/nginx-plus-go-sdk/client"
+	prometheusClient "github.com/nginxinc/nginx-prometheus-exporter/client"
+	"github.com/nginxinc/nginx-prometheus-exporter/collector"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+// metricsEndpoint is the path where prometheus metrics will be exposed
+const metricsEndpoint = "/metrics"
+
+// NewNginxMetricsClient creates an NginxClient to fetch stats from NGINX over an unix socket
+func NewNginxMetricsClient(httpClient *http.Client) (*prometheusClient.NginxClient, error) {
+	return prometheusClient.NewNginxClient(httpClient, "http://config-status/stub_status")
+}
+
+// RunPrometheusListenerForNginx runs an http server to expose Prometheus metrics for NGINX
+func RunPrometheusListenerForNginx(port int, client *prometheusClient.NginxClient) {
+	registry := prometheus.NewRegistry()
+	registry.MustRegister(collector.NewNginxCollector(client, "nginx"))
+	runServer(strconv.Itoa(port), registry)
+}
+
+// RunPrometheusListenerForNginxPlus runs an http server to expose Prometheus metrics for NGINX Plus
+func RunPrometheusListenerForNginxPlus(port int, plusClient *sdkClient.NginxClient) {
+	registry := prometheus.NewRegistry()
+	registry.MustRegister(collector.NewNginxPlusCollector(plusClient, "nginxplus"))
+	runServer(strconv.Itoa(port), registry)
+}
+
+func runServer(port string, registry prometheus.Gatherer) {
+	http.Handle(metricsEndpoint, promhttp.HandlerFor(registry, promhttp.HandlerOpts{}))
+
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte(`<html>
+			<head><title>NGINX Ingress Controller</title></head>
+			<body>
+			<h1>NGINX Ingress Controller</h1>
+			<p><a href='/metrics'>Metrics</a></p>
+			</body>
+			</html>`))
+	})
+	address := fmt.Sprintf(":%v", port)
+	glog.Infof("Starting Prometheus listener on: %v%v", address, metricsEndpoint)
+	glog.Fatal("Error in Prometheus listener server: ", http.ListenAndServe(address, nil))
+}
diff --git a/internal/nginx/configurator_test.go b/internal/nginx/configurator_test.go
index d86666a4d3..78285ba21e 100644
--- a/internal/nginx/configurator_test.go
+++ b/internal/nginx/configurator_test.go
@@ -524,7 +524,7 @@ func createExpectedConfigForMergeableCafeIngress() IngressNginxConfig {
 }
 
 func createTestConfigurator() (*Configurator, error) {
-	templateExecutor, err := NewTemplateExecutor("templates/nginx-plus.tmpl", "templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080)
+	templateExecutor, err := NewTemplateExecutor("templates/nginx-plus.tmpl", "templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080, false)
 	if err != nil {
 		return nil, err
 	}
@@ -537,7 +537,7 @@ func createTestConfigurator() (*Configurator, error) {
 }
 
 func createTestConfiguratorInvalidIngressTemplate() (*Configurator, error) {
-	templateExecutor, err := NewTemplateExecutor("templates/nginx-plus.tmpl", "templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080)
+	templateExecutor, err := NewTemplateExecutor("templates/nginx-plus.tmpl", "templates/nginx-plus.ingress.tmpl", true, true, []string{"127.0.0.1"}, 8080, false)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/nginx/nginx.go b/internal/nginx/nginx.go
index a48ba14eee..a82be44abf 100644
--- a/internal/nginx/nginx.go
+++ b/internal/nginx/nginx.go
@@ -151,18 +151,19 @@ type Location struct {
 
 // MainConfig describe the main NGINX configuration file
 type MainConfig struct {
-	ServerNamesHashBucketSize string
-	ServerNamesHashMaxSize    string
-	LogFormat                 string
-	ErrorLogLevel             string
-	StreamLogFormat           string
-	HealthStatus              bool
-	NginxStatus               bool
-	NginxStatusAllowCIDRs     []string
-	NginxStatusPort           int
-	MainSnippets              []string
-	HTTPSnippets              []string
-	StreamSnippets            []string
+	ServerNamesHashBucketSize      string
+	ServerNamesHashMaxSize         string
+	LogFormat                      string
+	ErrorLogLevel                  string
+	StreamLogFormat                string
+	HealthStatus                   bool
+	NginxStatus                    bool
+	NginxStatusAllowCIDRs          []string
+	NginxStatusPort                int
+	StubStatusOverUnixSocketForOSS bool
+	MainSnippets                   []string
+	HTTPSnippets                   []string
+	StreamSnippets                 []string
 	// http://nginx.org/en/docs/http/ngx_http_ssl_module.html
 	SSLProtocols           string
 	SSLPreferServerCiphers bool
diff --git a/internal/nginx/plus/nginx_api.go b/internal/nginx/plus/nginx_api.go
index 6d32c55d4d..208bc54531 100644
--- a/internal/nginx/plus/nginx_api.go
+++ b/internal/nginx/plus/nginx_api.go
@@ -84,3 +84,11 @@ func (nginx *NginxAPIController) UpdateServers(upstream string, servers []string
 	glog.V(3).Infof("Updated servers of %v; Added: %v, Removed: %v", upstream, added, removed)
 	return nil
 }
+
+// GetClientPlus returns the internal client for NGINX Plus API to reuse it outside the package
+func (nginx *NginxAPIController) GetClientPlus() *plus.NginxClient {
+	if nginx != nil && nginx.client != nil {
+		return nginx.client
+	}
+	return nil
+}
diff --git a/internal/nginx/template_executor.go b/internal/nginx/template_executor.go
index abafd77d29..ed21e30a37 100644
--- a/internal/nginx/template_executor.go
+++ b/internal/nginx/template_executor.go
@@ -8,16 +8,17 @@ import (
 
 // TemplateExecutor executes NGINX configuration templates
 type TemplateExecutor struct {
-	HealthStatus          bool
-	NginxStatus           bool
-	NginxStatusAllowCIDRs []string
-	NginxStatusPort       int
-	mainTemplate          *template.Template
-	ingressTemplate       *template.Template
+	HealthStatus                   bool
+	NginxStatus                    bool
+	NginxStatusAllowCIDRs          []string
+	NginxStatusPort                int
+	StubStatusOverUnixSocketForOSS bool
+	mainTemplate                   *template.Template
+	ingressTemplate                *template.Template
 }
 
 // NewTemplateExecutor creates a TemplateExecutor
-func NewTemplateExecutor(mainTemplatePath string, ingressTemplatePath string, healthStatus bool, nginxStatus bool, nginxStatusAllowCIDRs []string, nginxStatusPort int) (*TemplateExecutor, error) {
+func NewTemplateExecutor(mainTemplatePath string, ingressTemplatePath string, healthStatus bool, nginxStatus bool, nginxStatusAllowCIDRs []string, nginxStatusPort int, stubStatusOverUnixSocketForOSS bool) (*TemplateExecutor, error) {
 	// template name must be the base name of the template file https://golang.org/pkg/text/template/#Template.ParseFiles
 	nginxTemplate, err := template.New(path.Base(mainTemplatePath)).ParseFiles(mainTemplatePath)
 	if err != nil {
@@ -30,12 +31,13 @@ func NewTemplateExecutor(mainTemplatePath string, ingressTemplatePath string, he
 	}
 
 	return &TemplateExecutor{
-		mainTemplate:          nginxTemplate,
-		ingressTemplate:       ingressTemplate,
-		HealthStatus:          healthStatus,
-		NginxStatus:           nginxStatus,
-		NginxStatusAllowCIDRs: nginxStatusAllowCIDRs,
-		NginxStatusPort:       nginxStatusPort,
+		mainTemplate:                   nginxTemplate,
+		ingressTemplate:                ingressTemplate,
+		HealthStatus:                   healthStatus,
+		NginxStatus:                    nginxStatus,
+		NginxStatusAllowCIDRs:          nginxStatusAllowCIDRs,
+		NginxStatusPort:                nginxStatusPort,
+		StubStatusOverUnixSocketForOSS: stubStatusOverUnixSocketForOSS,
 	}, nil
 }
 
@@ -67,6 +69,7 @@ func (te *TemplateExecutor) ExecuteMainConfigTemplate(cfg *MainConfig) ([]byte,
 	cfg.NginxStatus = te.NginxStatus
 	cfg.NginxStatusAllowCIDRs = te.NginxStatusAllowCIDRs
 	cfg.NginxStatusPort = te.NginxStatusPort
+	cfg.StubStatusOverUnixSocketForOSS = te.StubStatusOverUnixSocketForOSS
 
 	var configBuffer bytes.Buffer
 	err := te.mainTemplate.Execute(&configBuffer, cfg)
diff --git a/internal/nginx/templates/nginx.tmpl b/internal/nginx/templates/nginx.tmpl
index 007cd3815f..13ccf425d5 100644
--- a/internal/nginx/templates/nginx.tmpl
+++ b/internal/nginx/templates/nginx.tmpl
@@ -94,6 +94,17 @@ http {
     }
     {{- end}}
 
+    {{- if .StubStatusOverUnixSocketForOSS }}
+    server {
+        listen unix:/var/run/nginx-status.sock;
+        access_log off;
+
+        location /stub_status {
+            stub_status;
+        }
+    }
+    {{- end}}
+
     include /etc/nginx/config-version.conf;
     include /etc/nginx/conf.d/*.conf;
 }
diff --git a/vendor/github.com/beorn7/perks/LICENSE b/vendor/github.com/beorn7/perks/LICENSE
new file mode 100644
index 0000000000..339177be66
--- /dev/null
+++ b/vendor/github.com/beorn7/perks/LICENSE
@@ -0,0 +1,20 @@
+Copyright (C) 2013 Blake Mizerany
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/vendor/github.com/beorn7/perks/quantile/exampledata.txt b/vendor/github.com/beorn7/perks/quantile/exampledata.txt
new file mode 100644
index 0000000000..1602287d7c
--- /dev/null
+++ b/vendor/github.com/beorn7/perks/quantile/exampledata.txt
@@ -0,0 +1,2388 @@
+8
+5
+26
+12
+5
+235
+13
+6
+28
+30
+3
+3
+3
+3
+5
+2
+33
+7
+2
+4
+7
+12
+14
+5
+8
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diff --git a/vendor/github.com/beorn7/perks/quantile/stream.go b/vendor/github.com/beorn7/perks/quantile/stream.go
new file mode 100644
index 0000000000..d7d14f8eb6
--- /dev/null
+++ b/vendor/github.com/beorn7/perks/quantile/stream.go
@@ -0,0 +1,316 @@
+// Package quantile computes approximate quantiles over an unbounded data
+// stream within low memory and CPU bounds.
+//
+// A small amount of accuracy is traded to achieve the above properties.
+//
+// Multiple streams can be merged before calling Query to generate a single set
+// of results. This is meaningful when the streams represent the same type of
+// data. See Merge and Samples.
+//
+// For more detailed information about the algorithm used, see:
+//
+// Effective Computation of Biased Quantiles over Data Streams
+//
+// http://www.cs.rutgers.edu/~muthu/bquant.pdf
+package quantile
+
+import (
+	"math"
+	"sort"
+)
+
+// Sample holds an observed value and meta information for compression. JSON
+// tags have been added for convenience.
+type Sample struct {
+	Value float64 `json:",string"`
+	Width float64 `json:",string"`
+	Delta float64 `json:",string"`
+}
+
+// Samples represents a slice of samples. It implements sort.Interface.
+type Samples []Sample
+
+func (a Samples) Len() int           { return len(a) }
+func (a Samples) Less(i, j int) bool { return a[i].Value < a[j].Value }
+func (a Samples) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+type invariant func(s *stream, r float64) float64
+
+// NewLowBiased returns an initialized Stream for low-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the lower ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within (1±Epsilon)*Quantile.
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewLowBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * r
+	}
+	return newStream(ƒ)
+}
+
+// NewHighBiased returns an initialized Stream for high-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the higher ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within 1-(1±Epsilon)*(1-Quantile).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewHighBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * (s.n - r)
+	}
+	return newStream(ƒ)
+}
+
+// NewTargeted returns an initialized Stream concerned with a particular set of
+// quantile values that are supplied a priori. Knowing these a priori reduces
+// space and computation time. The targets map maps the desired quantiles to
+// their absolute errors, i.e. the true quantile of a value returned by a query
+// is guaranteed to be within (Quantile±Epsilon).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error properties.
+func NewTargeted(targetMap map[float64]float64) *Stream {
+	// Convert map to slice to avoid slow iterations on a map.
+	// ƒ is called on the hot path, so converting the map to a slice
+	// beforehand results in significant CPU savings.
+	targets := targetMapToSlice(targetMap)
+
+	ƒ := func(s *stream, r float64) float64 {
+		var m = math.MaxFloat64
+		var f float64
+		for _, t := range targets {
+			if t.quantile*s.n <= r {
+				f = (2 * t.epsilon * r) / t.quantile
+			} else {
+				f = (2 * t.epsilon * (s.n - r)) / (1 - t.quantile)
+			}
+			if f < m {
+				m = f
+			}
+		}
+		return m
+	}
+	return newStream(ƒ)
+}
+
+type target struct {
+	quantile float64
+	epsilon  float64
+}
+
+func targetMapToSlice(targetMap map[float64]float64) []target {
+	targets := make([]target, 0, len(targetMap))
+
+	for quantile, epsilon := range targetMap {
+		t := target{
+			quantile: quantile,
+			epsilon:  epsilon,
+		}
+		targets = append(targets, t)
+	}
+
+	return targets
+}
+
+// Stream computes quantiles for a stream of float64s. It is not thread-safe by
+// design. Take care when using across multiple goroutines.
+type Stream struct {
+	*stream
+	b      Samples
+	sorted bool
+}
+
+func newStream(ƒ invariant) *Stream {
+	x := &stream{ƒ: ƒ}
+	return &Stream{x, make(Samples, 0, 500), true}
+}
+
+// Insert inserts v into the stream.
+func (s *Stream) Insert(v float64) {
+	s.insert(Sample{Value: v, Width: 1})
+}
+
+func (s *Stream) insert(sample Sample) {
+	s.b = append(s.b, sample)
+	s.sorted = false
+	if len(s.b) == cap(s.b) {
+		s.flush()
+	}
+}
+
+// Query returns the computed qth percentiles value. If s was created with
+// NewTargeted, and q is not in the set of quantiles provided a priori, Query
+// will return an unspecified result.
+func (s *Stream) Query(q float64) float64 {
+	if !s.flushed() {
+		// Fast path when there hasn't been enough data for a flush;
+		// this also yields better accuracy for small sets of data.
+		l := len(s.b)
+		if l == 0 {
+			return 0
+		}
+		i := int(math.Ceil(float64(l) * q))
+		if i > 0 {
+			i -= 1
+		}
+		s.maybeSort()
+		return s.b[i].Value
+	}
+	s.flush()
+	return s.stream.query(q)
+}
+
+// Merge merges samples into the underlying streams samples. This is handy when
+// merging multiple streams from separate threads, database shards, etc.
+//
+// ATTENTION: This method is broken and does not yield correct results. The
+// underlying algorithm is not capable of merging streams correctly.
+func (s *Stream) Merge(samples Samples) {
+	sort.Sort(samples)
+	s.stream.merge(samples)
+}
+
+// Reset reinitializes and clears the list reusing the samples buffer memory.
+func (s *Stream) Reset() {
+	s.stream.reset()
+	s.b = s.b[:0]
+}
+
+// Samples returns stream samples held by s.
+func (s *Stream) Samples() Samples {
+	if !s.flushed() {
+		return s.b
+	}
+	s.flush()
+	return s.stream.samples()
+}
+
+// Count returns the total number of samples observed in the stream
+// since initialization.
+func (s *Stream) Count() int {
+	return len(s.b) + s.stream.count()
+}
+
+func (s *Stream) flush() {
+	s.maybeSort()
+	s.stream.merge(s.b)
+	s.b = s.b[:0]
+}
+
+func (s *Stream) maybeSort() {
+	if !s.sorted {
+		s.sorted = true
+		sort.Sort(s.b)
+	}
+}
+
+func (s *Stream) flushed() bool {
+	return len(s.stream.l) > 0
+}
+
+type stream struct {
+	n float64
+	l []Sample
+	ƒ invariant
+}
+
+func (s *stream) reset() {
+	s.l = s.l[:0]
+	s.n = 0
+}
+
+func (s *stream) insert(v float64) {
+	s.merge(Samples{{v, 1, 0}})
+}
+
+func (s *stream) merge(samples Samples) {
+	// TODO(beorn7): This tries to merge not only individual samples, but
+	// whole summaries. The paper doesn't mention merging summaries at
+	// all. Unittests show that the merging is inaccurate. Find out how to
+	// do merges properly.
+	var r float64
+	i := 0
+	for _, sample := range samples {
+		for ; i < len(s.l); i++ {
+			c := s.l[i]
+			if c.Value > sample.Value {
+				// Insert at position i.
+				s.l = append(s.l, Sample{})
+				copy(s.l[i+1:], s.l[i:])
+				s.l[i] = Sample{
+					sample.Value,
+					sample.Width,
+					math.Max(sample.Delta, math.Floor(s.ƒ(s, r))-1),
+					// TODO(beorn7): How to calculate delta correctly?
+				}
+				i++
+				goto inserted
+			}
+			r += c.Width
+		}
+		s.l = append(s.l, Sample{sample.Value, sample.Width, 0})
+		i++
+	inserted:
+		s.n += sample.Width
+		r += sample.Width
+	}
+	s.compress()
+}
+
+func (s *stream) count() int {
+	return int(s.n)
+}
+
+func (s *stream) query(q float64) float64 {
+	t := math.Ceil(q * s.n)
+	t += math.Ceil(s.ƒ(s, t) / 2)
+	p := s.l[0]
+	var r float64
+	for _, c := range s.l[1:] {
+		r += p.Width
+		if r+c.Width+c.Delta > t {
+			return p.Value
+		}
+		p = c
+	}
+	return p.Value
+}
+
+func (s *stream) compress() {
+	if len(s.l) < 2 {
+		return
+	}
+	x := s.l[len(s.l)-1]
+	xi := len(s.l) - 1
+	r := s.n - 1 - x.Width
+
+	for i := len(s.l) - 2; i >= 0; i-- {
+		c := s.l[i]
+		if c.Width+x.Width+x.Delta <= s.ƒ(s, r) {
+			x.Width += c.Width
+			s.l[xi] = x
+			// Remove element at i.
+			copy(s.l[i:], s.l[i+1:])
+			s.l = s.l[:len(s.l)-1]
+			xi -= 1
+		} else {
+			x = c
+			xi = i
+		}
+		r -= c.Width
+	}
+}
+
+func (s *stream) samples() Samples {
+	samples := make(Samples, len(s.l))
+	copy(samples, s.l)
+	return samples
+}
diff --git a/vendor/github.com/golang/protobuf/LICENSE b/vendor/github.com/golang/protobuf/LICENSE
index 1b1b1921ef..0f646931a4 100644
--- a/vendor/github.com/golang/protobuf/LICENSE
+++ b/vendor/github.com/golang/protobuf/LICENSE
@@ -1,7 +1,4 @@
-Go support for Protocol Buffers - Google's data interchange format
-
 Copyright 2010 The Go Authors.  All rights reserved.
-https://github.com/golang/protobuf
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
diff --git a/vendor/github.com/golang/protobuf/proto/Makefile b/vendor/github.com/golang/protobuf/proto/Makefile
deleted file mode 100644
index e2e0651a93..0000000000
--- a/vendor/github.com/golang/protobuf/proto/Makefile
+++ /dev/null
@@ -1,43 +0,0 @@
-# Go support for Protocol Buffers - Google's data interchange format
-#
-# Copyright 2010 The Go Authors.  All rights reserved.
-# https://github.com/golang/protobuf
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
-#
-#     * Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above
-# copyright notice, this list of conditions and the following disclaimer
-# in the documentation and/or other materials provided with the
-# distribution.
-#     * Neither the name of Google Inc. nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-install:
-	go install
-
-test: install generate-test-pbs
-	go test
-
-
-generate-test-pbs:
-	make install
-	make -C testdata
-	protoc --go_out=Mtestdata/test.proto=github.com/golang/protobuf/proto/testdata,Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. proto3_proto/proto3.proto
-	make
diff --git a/vendor/github.com/golang/protobuf/proto/clone.go b/vendor/github.com/golang/protobuf/proto/clone.go
index e392575b35..3cd3249f70 100644
--- a/vendor/github.com/golang/protobuf/proto/clone.go
+++ b/vendor/github.com/golang/protobuf/proto/clone.go
@@ -35,22 +35,39 @@
 package proto
 
 import (
+	"fmt"
 	"log"
 	"reflect"
 	"strings"
 )
 
 // Clone returns a deep copy of a protocol buffer.
-func Clone(pb Message) Message {
-	in := reflect.ValueOf(pb)
+func Clone(src Message) Message {
+	in := reflect.ValueOf(src)
 	if in.IsNil() {
-		return pb
+		return src
 	}
-
 	out := reflect.New(in.Type().Elem())
-	// out is empty so a merge is a deep copy.
-	mergeStruct(out.Elem(), in.Elem())
-	return out.Interface().(Message)
+	dst := out.Interface().(Message)
+	Merge(dst, src)
+	return dst
+}
+
+// Merger is the interface representing objects that can merge messages of the same type.
+type Merger interface {
+	// Merge merges src into this message.
+	// Required and optional fields that are set in src will be set to that value in dst.
+	// Elements of repeated fields will be appended.
+	//
+	// Merge may panic if called with a different argument type than the receiver.
+	Merge(src Message)
+}
+
+// generatedMerger is the custom merge method that generated protos will have.
+// We must add this method since a generate Merge method will conflict with
+// many existing protos that have a Merge data field already defined.
+type generatedMerger interface {
+	XXX_Merge(src Message)
 }
 
 // Merge merges src into dst.
@@ -58,17 +75,24 @@ func Clone(pb Message) Message {
 // Elements of repeated fields will be appended.
 // Merge panics if src and dst are not the same type, or if dst is nil.
 func Merge(dst, src Message) {
+	if m, ok := dst.(Merger); ok {
+		m.Merge(src)
+		return
+	}
+
 	in := reflect.ValueOf(src)
 	out := reflect.ValueOf(dst)
 	if out.IsNil() {
 		panic("proto: nil destination")
 	}
 	if in.Type() != out.Type() {
-		// Explicit test prior to mergeStruct so that mistyped nils will fail
-		panic("proto: type mismatch")
+		panic(fmt.Sprintf("proto.Merge(%T, %T) type mismatch", dst, src))
 	}
 	if in.IsNil() {
-		// Merging nil into non-nil is a quiet no-op
+		return // Merge from nil src is a noop
+	}
+	if m, ok := dst.(generatedMerger); ok {
+		m.XXX_Merge(src)
 		return
 	}
 	mergeStruct(out.Elem(), in.Elem())
@@ -84,7 +108,7 @@ func mergeStruct(out, in reflect.Value) {
 		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
 	}
 
-	if emIn, ok := extendable(in.Addr().Interface()); ok {
+	if emIn, err := extendable(in.Addr().Interface()); err == nil {
 		emOut, _ := extendable(out.Addr().Interface())
 		mIn, muIn := emIn.extensionsRead()
 		if mIn != nil {
diff --git a/vendor/github.com/golang/protobuf/proto/decode.go b/vendor/github.com/golang/protobuf/proto/decode.go
index aa207298f9..63b0f08bef 100644
--- a/vendor/github.com/golang/protobuf/proto/decode.go
+++ b/vendor/github.com/golang/protobuf/proto/decode.go
@@ -39,8 +39,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"os"
-	"reflect"
 )
 
 // errOverflow is returned when an integer is too large to be represented.
@@ -50,10 +48,6 @@ var errOverflow = errors.New("proto: integer overflow")
 // wire type is encountered. It does not get returned to user code.
 var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
 
-// The fundamental decoders that interpret bytes on the wire.
-// Those that take integer types all return uint64 and are
-// therefore of type valueDecoder.
-
 // DecodeVarint reads a varint-encoded integer from the slice.
 // It returns the integer and the number of bytes consumed, or
 // zero if there is not enough.
@@ -192,7 +186,6 @@ func (p *Buffer) DecodeVarint() (x uint64, err error) {
 	if b&0x80 == 0 {
 		goto done
 	}
-	// x -= 0x80 << 63 // Always zero.
 
 	return 0, errOverflow
 
@@ -267,9 +260,6 @@ func (p *Buffer) DecodeZigzag32() (x uint64, err error) {
 	return
 }
 
-// These are not ValueDecoders: they produce an array of bytes or a string.
-// bytes, embedded messages
-
 // DecodeRawBytes reads a count-delimited byte buffer from the Buffer.
 // This is the format used for the bytes protocol buffer
 // type and for embedded messages.
@@ -311,81 +301,29 @@ func (p *Buffer) DecodeStringBytes() (s string, err error) {
 	return string(buf), nil
 }
 
-// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
-// If the protocol buffer has extensions, and the field matches, add it as an extension.
-// Otherwise, if the XXX_unrecognized field exists, append the skipped data there.
-func (o *Buffer) skipAndSave(t reflect.Type, tag, wire int, base structPointer, unrecField field) error {
-	oi := o.index
-
-	err := o.skip(t, tag, wire)
-	if err != nil {
-		return err
-	}
-
-	if !unrecField.IsValid() {
-		return nil
-	}
-
-	ptr := structPointer_Bytes(base, unrecField)
-
-	// Add the skipped field to struct field
-	obuf := o.buf
-
-	o.buf = *ptr
-	o.EncodeVarint(uint64(tag<<3 | wire))
-	*ptr = append(o.buf, obuf[oi:o.index]...)
-
-	o.buf = obuf
-
-	return nil
-}
-
-// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
-func (o *Buffer) skip(t reflect.Type, tag, wire int) error {
-
-	var u uint64
-	var err error
-
-	switch wire {
-	case WireVarint:
-		_, err = o.DecodeVarint()
-	case WireFixed64:
-		_, err = o.DecodeFixed64()
-	case WireBytes:
-		_, err = o.DecodeRawBytes(false)
-	case WireFixed32:
-		_, err = o.DecodeFixed32()
-	case WireStartGroup:
-		for {
-			u, err = o.DecodeVarint()
-			if err != nil {
-				break
-			}
-			fwire := int(u & 0x7)
-			if fwire == WireEndGroup {
-				break
-			}
-			ftag := int(u >> 3)
-			err = o.skip(t, ftag, fwire)
-			if err != nil {
-				break
-			}
-		}
-	default:
-		err = fmt.Errorf("proto: can't skip unknown wire type %d for %s", wire, t)
-	}
-	return err
-}
-
 // Unmarshaler is the interface representing objects that can
-// unmarshal themselves.  The method should reset the receiver before
-// decoding starts.  The argument points to data that may be
+// unmarshal themselves.  The argument points to data that may be
 // overwritten, so implementations should not keep references to the
 // buffer.
+// Unmarshal implementations should not clear the receiver.
+// Any unmarshaled data should be merged into the receiver.
+// Callers of Unmarshal that do not want to retain existing data
+// should Reset the receiver before calling Unmarshal.
 type Unmarshaler interface {
 	Unmarshal([]byte) error
 }
 
+// newUnmarshaler is the interface representing objects that can
+// unmarshal themselves. The semantics are identical to Unmarshaler.
+//
+// This exists to support protoc-gen-go generated messages.
+// The proto package will stop type-asserting to this interface in the future.
+//
+// DO NOT DEPEND ON THIS.
+type newUnmarshaler interface {
+	XXX_Unmarshal([]byte) error
+}
+
 // Unmarshal parses the protocol buffer representation in buf and places the
 // decoded result in pb.  If the struct underlying pb does not match
 // the data in buf, the results can be unpredictable.
@@ -395,7 +333,13 @@ type Unmarshaler interface {
 // to preserve and append to existing data.
 func Unmarshal(buf []byte, pb Message) error {
 	pb.Reset()
-	return UnmarshalMerge(buf, pb)
+	if u, ok := pb.(newUnmarshaler); ok {
+		return u.XXX_Unmarshal(buf)
+	}
+	if u, ok := pb.(Unmarshaler); ok {
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
 }
 
 // UnmarshalMerge parses the protocol buffer representation in buf and
@@ -405,8 +349,16 @@ func Unmarshal(buf []byte, pb Message) error {
 // UnmarshalMerge merges into existing data in pb.
 // Most code should use Unmarshal instead.
 func UnmarshalMerge(buf []byte, pb Message) error {
-	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(newUnmarshaler); ok {
+		return u.XXX_Unmarshal(buf)
+	}
 	if u, ok := pb.(Unmarshaler); ok {
+		// NOTE: The history of proto have unfortunately been inconsistent
+		// whether Unmarshaler should or should not implicitly clear itself.
+		// Some implementations do, most do not.
+		// Thus, calling this here may or may not do what people want.
+		//
+		// See https://github.com/golang/protobuf/issues/424
 		return u.Unmarshal(buf)
 	}
 	return NewBuffer(buf).Unmarshal(pb)
@@ -422,12 +374,17 @@ func (p *Buffer) DecodeMessage(pb Message) error {
 }
 
 // DecodeGroup reads a tag-delimited group from the Buffer.
+// StartGroup tag is already consumed. This function consumes
+// EndGroup tag.
 func (p *Buffer) DecodeGroup(pb Message) error {
-	typ, base, err := getbase(pb)
-	if err != nil {
-		return err
+	b := p.buf[p.index:]
+	x, y := findEndGroup(b)
+	if x < 0 {
+		return io.ErrUnexpectedEOF
 	}
-	return p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), true, base)
+	err := Unmarshal(b[:x], pb)
+	p.index += y
+	return err
 }
 
 // Unmarshal parses the protocol buffer representation in the
@@ -438,533 +395,33 @@ func (p *Buffer) DecodeGroup(pb Message) error {
 // Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
 func (p *Buffer) Unmarshal(pb Message) error {
 	// If the object can unmarshal itself, let it.
-	if u, ok := pb.(Unmarshaler); ok {
-		err := u.Unmarshal(p.buf[p.index:])
+	if u, ok := pb.(newUnmarshaler); ok {
+		err := u.XXX_Unmarshal(p.buf[p.index:])
 		p.index = len(p.buf)
 		return err
 	}
-
-	typ, base, err := getbase(pb)
-	if err != nil {
-		return err
-	}
-
-	err = p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), false, base)
-
-	if collectStats {
-		stats.Decode++
-	}
-
-	return err
-}
-
-// unmarshalType does the work of unmarshaling a structure.
-func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group bool, base structPointer) error {
-	var state errorState
-	required, reqFields := prop.reqCount, uint64(0)
-
-	var err error
-	for err == nil && o.index < len(o.buf) {
-		oi := o.index
-		var u uint64
-		u, err = o.DecodeVarint()
-		if err != nil {
-			break
-		}
-		wire := int(u & 0x7)
-		if wire == WireEndGroup {
-			if is_group {
-				if required > 0 {
-					// Not enough information to determine the exact field.
-					// (See below.)
-					return &RequiredNotSetError{"{Unknown}"}
-				}
-				return nil // input is satisfied
-			}
-			return fmt.Errorf("proto: %s: wiretype end group for non-group", st)
-		}
-		tag := int(u >> 3)
-		if tag <= 0 {
-			return fmt.Errorf("proto: %s: illegal tag %d (wire type %d)", st, tag, wire)
-		}
-		fieldnum, ok := prop.decoderTags.get(tag)
-		if !ok {
-			// Maybe it's an extension?
-			if prop.extendable {
-				if e, _ := extendable(structPointer_Interface(base, st)); isExtensionField(e, int32(tag)) {
-					if err = o.skip(st, tag, wire); err == nil {
-						extmap := e.extensionsWrite()
-						ext := extmap[int32(tag)] // may be missing
-						ext.enc = append(ext.enc, o.buf[oi:o.index]...)
-						extmap[int32(tag)] = ext
-					}
-					continue
-				}
-			}
-			// Maybe it's a oneof?
-			if prop.oneofUnmarshaler != nil {
-				m := structPointer_Interface(base, st).(Message)
-				// First return value indicates whether tag is a oneof field.
-				ok, err = prop.oneofUnmarshaler(m, tag, wire, o)
-				if err == ErrInternalBadWireType {
-					// Map the error to something more descriptive.
-					// Do the formatting here to save generated code space.
-					err = fmt.Errorf("bad wiretype for oneof field in %T", m)
-				}
-				if ok {
-					continue
-				}
-			}
-			err = o.skipAndSave(st, tag, wire, base, prop.unrecField)
-			continue
-		}
-		p := prop.Prop[fieldnum]
-
-		if p.dec == nil {
-			fmt.Fprintf(os.Stderr, "proto: no protobuf decoder for %s.%s\n", st, st.Field(fieldnum).Name)
-			continue
-		}
-		dec := p.dec
-		if wire != WireStartGroup && wire != p.WireType {
-			if wire == WireBytes && p.packedDec != nil {
-				// a packable field
-				dec = p.packedDec
-			} else {
-				err = fmt.Errorf("proto: bad wiretype for field %s.%s: got wiretype %d, want %d", st, st.Field(fieldnum).Name, wire, p.WireType)
-				continue
-			}
-		}
-		decErr := dec(o, p, base)
-		if decErr != nil && !state.shouldContinue(decErr, p) {
-			err = decErr
-		}
-		if err == nil && p.Required {
-			// Successfully decoded a required field.
-			if tag <= 64 {
-				// use bitmap for fields 1-64 to catch field reuse.
-				var mask uint64 = 1 << uint64(tag-1)
-				if reqFields&mask == 0 {
-					// new required field
-					reqFields |= mask
-					required--
-				}
-			} else {
-				// This is imprecise. It can be fooled by a required field
-				// with a tag > 64 that is encoded twice; that's very rare.
-				// A fully correct implementation would require allocating
-				// a data structure, which we would like to avoid.
-				required--
-			}
-		}
-	}
-	if err == nil {
-		if is_group {
-			return io.ErrUnexpectedEOF
-		}
-		if state.err != nil {
-			return state.err
-		}
-		if required > 0 {
-			// Not enough information to determine the exact field. If we use extra
-			// CPU, we could determine the field only if the missing required field
-			// has a tag <= 64 and we check reqFields.
-			return &RequiredNotSetError{"{Unknown}"}
-		}
-	}
-	return err
-}
-
-// Individual type decoders
-// For each,
-//	u is the decoded value,
-//	v is a pointer to the field (pointer) in the struct
-
-// Sizes of the pools to allocate inside the Buffer.
-// The goal is modest amortization and allocation
-// on at least 16-byte boundaries.
-const (
-	boolPoolSize   = 16
-	uint32PoolSize = 8
-	uint64PoolSize = 4
-)
-
-// Decode a bool.
-func (o *Buffer) dec_bool(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	if len(o.bools) == 0 {
-		o.bools = make([]bool, boolPoolSize)
-	}
-	o.bools[0] = u != 0
-	*structPointer_Bool(base, p.field) = &o.bools[0]
-	o.bools = o.bools[1:]
-	return nil
-}
-
-func (o *Buffer) dec_proto3_bool(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	*structPointer_BoolVal(base, p.field) = u != 0
-	return nil
-}
-
-// Decode an int32.
-func (o *Buffer) dec_int32(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	word32_Set(structPointer_Word32(base, p.field), o, uint32(u))
-	return nil
-}
-
-func (o *Buffer) dec_proto3_int32(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	word32Val_Set(structPointer_Word32Val(base, p.field), uint32(u))
-	return nil
-}
-
-// Decode an int64.
-func (o *Buffer) dec_int64(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	word64_Set(structPointer_Word64(base, p.field), o, u)
-	return nil
-}
-
-func (o *Buffer) dec_proto3_int64(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	word64Val_Set(structPointer_Word64Val(base, p.field), o, u)
-	return nil
-}
-
-// Decode a string.
-func (o *Buffer) dec_string(p *Properties, base structPointer) error {
-	s, err := o.DecodeStringBytes()
-	if err != nil {
-		return err
-	}
-	*structPointer_String(base, p.field) = &s
-	return nil
-}
-
-func (o *Buffer) dec_proto3_string(p *Properties, base structPointer) error {
-	s, err := o.DecodeStringBytes()
-	if err != nil {
-		return err
-	}
-	*structPointer_StringVal(base, p.field) = s
-	return nil
-}
-
-// Decode a slice of bytes ([]byte).
-func (o *Buffer) dec_slice_byte(p *Properties, base structPointer) error {
-	b, err := o.DecodeRawBytes(true)
-	if err != nil {
-		return err
-	}
-	*structPointer_Bytes(base, p.field) = b
-	return nil
-}
-
-// Decode a slice of bools ([]bool).
-func (o *Buffer) dec_slice_bool(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	v := structPointer_BoolSlice(base, p.field)
-	*v = append(*v, u != 0)
-	return nil
-}
-
-// Decode a slice of bools ([]bool) in packed format.
-func (o *Buffer) dec_slice_packed_bool(p *Properties, base structPointer) error {
-	v := structPointer_BoolSlice(base, p.field)
-
-	nn, err := o.DecodeVarint()
-	if err != nil {
-		return err
-	}
-	nb := int(nn) // number of bytes of encoded bools
-	fin := o.index + nb
-	if fin < o.index {
-		return errOverflow
-	}
-
-	y := *v
-	for o.index < fin {
-		u, err := p.valDec(o)
-		if err != nil {
-			return err
-		}
-		y = append(y, u != 0)
-	}
-
-	*v = y
-	return nil
-}
-
-// Decode a slice of int32s ([]int32).
-func (o *Buffer) dec_slice_int32(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-	structPointer_Word32Slice(base, p.field).Append(uint32(u))
-	return nil
-}
-
-// Decode a slice of int32s ([]int32) in packed format.
-func (o *Buffer) dec_slice_packed_int32(p *Properties, base structPointer) error {
-	v := structPointer_Word32Slice(base, p.field)
-
-	nn, err := o.DecodeVarint()
-	if err != nil {
-		return err
-	}
-	nb := int(nn) // number of bytes of encoded int32s
-
-	fin := o.index + nb
-	if fin < o.index {
-		return errOverflow
-	}
-	for o.index < fin {
-		u, err := p.valDec(o)
-		if err != nil {
-			return err
-		}
-		v.Append(uint32(u))
-	}
-	return nil
-}
-
-// Decode a slice of int64s ([]int64).
-func (o *Buffer) dec_slice_int64(p *Properties, base structPointer) error {
-	u, err := p.valDec(o)
-	if err != nil {
-		return err
-	}
-
-	structPointer_Word64Slice(base, p.field).Append(u)
-	return nil
-}
-
-// Decode a slice of int64s ([]int64) in packed format.
-func (o *Buffer) dec_slice_packed_int64(p *Properties, base structPointer) error {
-	v := structPointer_Word64Slice(base, p.field)
-
-	nn, err := o.DecodeVarint()
-	if err != nil {
-		return err
-	}
-	nb := int(nn) // number of bytes of encoded int64s
-
-	fin := o.index + nb
-	if fin < o.index {
-		return errOverflow
-	}
-	for o.index < fin {
-		u, err := p.valDec(o)
-		if err != nil {
-			return err
-		}
-		v.Append(u)
-	}
-	return nil
-}
-
-// Decode a slice of strings ([]string).
-func (o *Buffer) dec_slice_string(p *Properties, base structPointer) error {
-	s, err := o.DecodeStringBytes()
-	if err != nil {
-		return err
-	}
-	v := structPointer_StringSlice(base, p.field)
-	*v = append(*v, s)
-	return nil
-}
-
-// Decode a slice of slice of bytes ([][]byte).
-func (o *Buffer) dec_slice_slice_byte(p *Properties, base structPointer) error {
-	b, err := o.DecodeRawBytes(true)
-	if err != nil {
-		return err
-	}
-	v := structPointer_BytesSlice(base, p.field)
-	*v = append(*v, b)
-	return nil
-}
-
-// Decode a map field.
-func (o *Buffer) dec_new_map(p *Properties, base structPointer) error {
-	raw, err := o.DecodeRawBytes(false)
-	if err != nil {
-		return err
-	}
-	oi := o.index       // index at the end of this map entry
-	o.index -= len(raw) // move buffer back to start of map entry
-
-	mptr := structPointer_NewAt(base, p.field, p.mtype) // *map[K]V
-	if mptr.Elem().IsNil() {
-		mptr.Elem().Set(reflect.MakeMap(mptr.Type().Elem()))
-	}
-	v := mptr.Elem() // map[K]V
-
-	// Prepare addressable doubly-indirect placeholders for the key and value types.
-	// See enc_new_map for why.
-	keyptr := reflect.New(reflect.PtrTo(p.mtype.Key())).Elem() // addressable *K
-	keybase := toStructPointer(keyptr.Addr())                  // **K
-
-	var valbase structPointer
-	var valptr reflect.Value
-	switch p.mtype.Elem().Kind() {
-	case reflect.Slice:
-		// []byte
-		var dummy []byte
-		valptr = reflect.ValueOf(&dummy)  // *[]byte
-		valbase = toStructPointer(valptr) // *[]byte
-	case reflect.Ptr:
-		// message; valptr is **Msg; need to allocate the intermediate pointer
-		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
-		valptr.Set(reflect.New(valptr.Type().Elem()))
-		valbase = toStructPointer(valptr)
-	default:
-		// everything else
-		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
-		valbase = toStructPointer(valptr.Addr())                   // **V
-	}
-
-	// Decode.
-	// This parses a restricted wire format, namely the encoding of a message
-	// with two fields. See enc_new_map for the format.
-	for o.index < oi {
-		// tagcode for key and value properties are always a single byte
-		// because they have tags 1 and 2.
-		tagcode := o.buf[o.index]
-		o.index++
-		switch tagcode {
-		case p.mkeyprop.tagcode[0]:
-			if err := p.mkeyprop.dec(o, p.mkeyprop, keybase); err != nil {
-				return err
-			}
-		case p.mvalprop.tagcode[0]:
-			if err := p.mvalprop.dec(o, p.mvalprop, valbase); err != nil {
-				return err
-			}
-		default:
-			// TODO: Should we silently skip this instead?
-			return fmt.Errorf("proto: bad map data tag %d", raw[0])
-		}
-	}
-	keyelem, valelem := keyptr.Elem(), valptr.Elem()
-	if !keyelem.IsValid() {
-		keyelem = reflect.Zero(p.mtype.Key())
-	}
-	if !valelem.IsValid() {
-		valelem = reflect.Zero(p.mtype.Elem())
-	}
-
-	v.SetMapIndex(keyelem, valelem)
-	return nil
-}
-
-// Decode a group.
-func (o *Buffer) dec_struct_group(p *Properties, base structPointer) error {
-	bas := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(bas) {
-		// allocate new nested message
-		bas = toStructPointer(reflect.New(p.stype))
-		structPointer_SetStructPointer(base, p.field, bas)
-	}
-	return o.unmarshalType(p.stype, p.sprop, true, bas)
-}
-
-// Decode an embedded message.
-func (o *Buffer) dec_struct_message(p *Properties, base structPointer) (err error) {
-	raw, e := o.DecodeRawBytes(false)
-	if e != nil {
-		return e
-	}
-
-	bas := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(bas) {
-		// allocate new nested message
-		bas = toStructPointer(reflect.New(p.stype))
-		structPointer_SetStructPointer(base, p.field, bas)
-	}
-
-	// If the object can unmarshal itself, let it.
-	if p.isUnmarshaler {
-		iv := structPointer_Interface(bas, p.stype)
-		return iv.(Unmarshaler).Unmarshal(raw)
-	}
-
-	obuf := o.buf
-	oi := o.index
-	o.buf = raw
-	o.index = 0
-
-	err = o.unmarshalType(p.stype, p.sprop, false, bas)
-	o.buf = obuf
-	o.index = oi
-
-	return err
-}
-
-// Decode a slice of embedded messages.
-func (o *Buffer) dec_slice_struct_message(p *Properties, base structPointer) error {
-	return o.dec_slice_struct(p, false, base)
-}
-
-// Decode a slice of embedded groups.
-func (o *Buffer) dec_slice_struct_group(p *Properties, base structPointer) error {
-	return o.dec_slice_struct(p, true, base)
-}
-
-// Decode a slice of structs ([]*struct).
-func (o *Buffer) dec_slice_struct(p *Properties, is_group bool, base structPointer) error {
-	v := reflect.New(p.stype)
-	bas := toStructPointer(v)
-	structPointer_StructPointerSlice(base, p.field).Append(bas)
-
-	if is_group {
-		err := o.unmarshalType(p.stype, p.sprop, is_group, bas)
-		return err
-	}
-
-	raw, err := o.DecodeRawBytes(false)
-	if err != nil {
+	if u, ok := pb.(Unmarshaler); ok {
+		// NOTE: The history of proto have unfortunately been inconsistent
+		// whether Unmarshaler should or should not implicitly clear itself.
+		// Some implementations do, most do not.
+		// Thus, calling this here may or may not do what people want.
+		//
+		// See https://github.com/golang/protobuf/issues/424
+		err := u.Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
 		return err
 	}
 
-	// If the object can unmarshal itself, let it.
-	if p.isUnmarshaler {
-		iv := v.Interface()
-		return iv.(Unmarshaler).Unmarshal(raw)
-	}
-
-	obuf := o.buf
-	oi := o.index
-	o.buf = raw
-	o.index = 0
-
-	err = o.unmarshalType(p.stype, p.sprop, is_group, bas)
-
-	o.buf = obuf
-	o.index = oi
-
+	// Slow workaround for messages that aren't Unmarshalers.
+	// This includes some hand-coded .pb.go files and
+	// bootstrap protos.
+	// TODO: fix all of those and then add Unmarshal to
+	// the Message interface. Then:
+	// The cast above and code below can be deleted.
+	// The old unmarshaler can be deleted.
+	// Clients can call Unmarshal directly (can already do that, actually).
+	var info InternalMessageInfo
+	err := info.Unmarshal(pb, p.buf[p.index:])
+	p.index = len(p.buf)
 	return err
 }
diff --git a/vendor/github.com/golang/protobuf/proto/deprecated.go b/vendor/github.com/golang/protobuf/proto/deprecated.go
new file mode 100644
index 0000000000..35b882c09a
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/deprecated.go
@@ -0,0 +1,63 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2018 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import "errors"
+
+// Deprecated: do not use.
+type Stats struct{ Emalloc, Dmalloc, Encode, Decode, Chit, Cmiss, Size uint64 }
+
+// Deprecated: do not use.
+func GetStats() Stats { return Stats{} }
+
+// Deprecated: do not use.
+func MarshalMessageSet(interface{}) ([]byte, error) {
+	return nil, errors.New("proto: not implemented")
+}
+
+// Deprecated: do not use.
+func UnmarshalMessageSet([]byte, interface{}) error {
+	return errors.New("proto: not implemented")
+}
+
+// Deprecated: do not use.
+func MarshalMessageSetJSON(interface{}) ([]byte, error) {
+	return nil, errors.New("proto: not implemented")
+}
+
+// Deprecated: do not use.
+func UnmarshalMessageSetJSON([]byte, interface{}) error {
+	return errors.New("proto: not implemented")
+}
+
+// Deprecated: do not use.
+func RegisterMessageSetType(Message, int32, string) {}
diff --git a/vendor/github.com/golang/protobuf/proto/discard.go b/vendor/github.com/golang/protobuf/proto/discard.go
new file mode 100644
index 0000000000..dea2617ced
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/discard.go
@@ -0,0 +1,350 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2017 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+type generatedDiscarder interface {
+	XXX_DiscardUnknown()
+}
+
+// DiscardUnknown recursively discards all unknown fields from this message
+// and all embedded messages.
+//
+// When unmarshaling a message with unrecognized fields, the tags and values
+// of such fields are preserved in the Message. This allows a later call to
+// marshal to be able to produce a message that continues to have those
+// unrecognized fields. To avoid this, DiscardUnknown is used to
+// explicitly clear the unknown fields after unmarshaling.
+//
+// For proto2 messages, the unknown fields of message extensions are only
+// discarded from messages that have been accessed via GetExtension.
+func DiscardUnknown(m Message) {
+	if m, ok := m.(generatedDiscarder); ok {
+		m.XXX_DiscardUnknown()
+		return
+	}
+	// TODO: Dynamically populate a InternalMessageInfo for legacy messages,
+	// but the master branch has no implementation for InternalMessageInfo,
+	// so it would be more work to replicate that approach.
+	discardLegacy(m)
+}
+
+// DiscardUnknown recursively discards all unknown fields.
+func (a *InternalMessageInfo) DiscardUnknown(m Message) {
+	di := atomicLoadDiscardInfo(&a.discard)
+	if di == nil {
+		di = getDiscardInfo(reflect.TypeOf(m).Elem())
+		atomicStoreDiscardInfo(&a.discard, di)
+	}
+	di.discard(toPointer(&m))
+}
+
+type discardInfo struct {
+	typ reflect.Type
+
+	initialized int32 // 0: only typ is valid, 1: everything is valid
+	lock        sync.Mutex
+
+	fields       []discardFieldInfo
+	unrecognized field
+}
+
+type discardFieldInfo struct {
+	field   field // Offset of field, guaranteed to be valid
+	discard func(src pointer)
+}
+
+var (
+	discardInfoMap  = map[reflect.Type]*discardInfo{}
+	discardInfoLock sync.Mutex
+)
+
+func getDiscardInfo(t reflect.Type) *discardInfo {
+	discardInfoLock.Lock()
+	defer discardInfoLock.Unlock()
+	di := discardInfoMap[t]
+	if di == nil {
+		di = &discardInfo{typ: t}
+		discardInfoMap[t] = di
+	}
+	return di
+}
+
+func (di *discardInfo) discard(src pointer) {
+	if src.isNil() {
+		return // Nothing to do.
+	}
+
+	if atomic.LoadInt32(&di.initialized) == 0 {
+		di.computeDiscardInfo()
+	}
+
+	for _, fi := range di.fields {
+		sfp := src.offset(fi.field)
+		fi.discard(sfp)
+	}
+
+	// For proto2 messages, only discard unknown fields in message extensions
+	// that have been accessed via GetExtension.
+	if em, err := extendable(src.asPointerTo(di.typ).Interface()); err == nil {
+		// Ignore lock since DiscardUnknown is not concurrency safe.
+		emm, _ := em.extensionsRead()
+		for _, mx := range emm {
+			if m, ok := mx.value.(Message); ok {
+				DiscardUnknown(m)
+			}
+		}
+	}
+
+	if di.unrecognized.IsValid() {
+		*src.offset(di.unrecognized).toBytes() = nil
+	}
+}
+
+func (di *discardInfo) computeDiscardInfo() {
+	di.lock.Lock()
+	defer di.lock.Unlock()
+	if di.initialized != 0 {
+		return
+	}
+	t := di.typ
+	n := t.NumField()
+
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+
+		dfi := discardFieldInfo{field: toField(&f)}
+		tf := f.Type
+
+		// Unwrap tf to get its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("%v.%s cannot be a slice of pointers to primitive types", t, f.Name))
+		}
+
+		switch tf.Kind() {
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("%v.%s cannot be a direct struct value", t, f.Name))
+			case isSlice: // E.g., []*pb.T
+				di := getDiscardInfo(tf)
+				dfi.discard = func(src pointer) {
+					sps := src.getPointerSlice()
+					for _, sp := range sps {
+						if !sp.isNil() {
+							di.discard(sp)
+						}
+					}
+				}
+			default: // E.g., *pb.T
+				di := getDiscardInfo(tf)
+				dfi.discard = func(src pointer) {
+					sp := src.getPointer()
+					if !sp.isNil() {
+						di.discard(sp)
+					}
+				}
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%v.%s cannot be a pointer to a map or a slice of map values", t, f.Name))
+			default: // E.g., map[K]V
+				if tf.Elem().Kind() == reflect.Ptr { // Proto struct (e.g., *T)
+					dfi.discard = func(src pointer) {
+						sm := src.asPointerTo(tf).Elem()
+						if sm.Len() == 0 {
+							return
+						}
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							DiscardUnknown(val.Interface().(Message))
+						}
+					}
+				} else {
+					dfi.discard = func(pointer) {} // Noop
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%v.%s cannot be a pointer to a interface or a slice of interface values", t, f.Name))
+			default: // E.g., interface{}
+				// TODO: Make this faster?
+				dfi.discard = func(src pointer) {
+					su := src.asPointerTo(tf).Elem()
+					if !su.IsNil() {
+						sv := su.Elem().Elem().Field(0)
+						if sv.Kind() == reflect.Ptr && sv.IsNil() {
+							return
+						}
+						switch sv.Type().Kind() {
+						case reflect.Ptr: // Proto struct (e.g., *T)
+							DiscardUnknown(sv.Interface().(Message))
+						}
+					}
+				}
+			}
+		default:
+			continue
+		}
+		di.fields = append(di.fields, dfi)
+	}
+
+	di.unrecognized = invalidField
+	if f, ok := t.FieldByName("XXX_unrecognized"); ok {
+		if f.Type != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		di.unrecognized = toField(&f)
+	}
+
+	atomic.StoreInt32(&di.initialized, 1)
+}
+
+func discardLegacy(m Message) {
+	v := reflect.ValueOf(m)
+	if v.Kind() != reflect.Ptr || v.IsNil() {
+		return
+	}
+	v = v.Elem()
+	if v.Kind() != reflect.Struct {
+		return
+	}
+	t := v.Type()
+
+	for i := 0; i < v.NumField(); i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		vf := v.Field(i)
+		tf := f.Type
+
+		// Unwrap tf to get its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("%T.%s cannot be a slice of pointers to primitive types", m, f.Name))
+		}
+
+		switch tf.Kind() {
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("%T.%s cannot be a direct struct value", m, f.Name))
+			case isSlice: // E.g., []*pb.T
+				for j := 0; j < vf.Len(); j++ {
+					discardLegacy(vf.Index(j).Interface().(Message))
+				}
+			default: // E.g., *pb.T
+				discardLegacy(vf.Interface().(Message))
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a map or a slice of map values", m, f.Name))
+			default: // E.g., map[K]V
+				tv := vf.Type().Elem()
+				if tv.Kind() == reflect.Ptr && tv.Implements(protoMessageType) { // Proto struct (e.g., *T)
+					for _, key := range vf.MapKeys() {
+						val := vf.MapIndex(key)
+						discardLegacy(val.Interface().(Message))
+					}
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a interface or a slice of interface values", m, f.Name))
+			default: // E.g., test_proto.isCommunique_Union interface
+				if !vf.IsNil() && f.Tag.Get("protobuf_oneof") != "" {
+					vf = vf.Elem() // E.g., *test_proto.Communique_Msg
+					if !vf.IsNil() {
+						vf = vf.Elem()   // E.g., test_proto.Communique_Msg
+						vf = vf.Field(0) // E.g., Proto struct (e.g., *T) or primitive value
+						if vf.Kind() == reflect.Ptr {
+							discardLegacy(vf.Interface().(Message))
+						}
+					}
+				}
+			}
+		}
+	}
+
+	if vf := v.FieldByName("XXX_unrecognized"); vf.IsValid() {
+		if vf.Type() != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		vf.Set(reflect.ValueOf([]byte(nil)))
+	}
+
+	// For proto2 messages, only discard unknown fields in message extensions
+	// that have been accessed via GetExtension.
+	if em, err := extendable(m); err == nil {
+		// Ignore lock since discardLegacy is not concurrency safe.
+		emm, _ := em.extensionsRead()
+		for _, mx := range emm {
+			if m, ok := mx.value.(Message); ok {
+				discardLegacy(m)
+			}
+		}
+	}
+}
diff --git a/vendor/github.com/golang/protobuf/proto/encode.go b/vendor/github.com/golang/protobuf/proto/encode.go
index 8b84d1b22d..3abfed2cff 100644
--- a/vendor/github.com/golang/protobuf/proto/encode.go
+++ b/vendor/github.com/golang/protobuf/proto/encode.go
@@ -37,28 +37,9 @@ package proto
 
 import (
 	"errors"
-	"fmt"
 	"reflect"
-	"sort"
 )
 
-// RequiredNotSetError is the error returned if Marshal is called with
-// a protocol buffer struct whose required fields have not
-// all been initialized. It is also the error returned if Unmarshal is
-// called with an encoded protocol buffer that does not include all the
-// required fields.
-//
-// When printed, RequiredNotSetError reports the first unset required field in a
-// message. If the field cannot be precisely determined, it is reported as
-// "{Unknown}".
-type RequiredNotSetError struct {
-	field string
-}
-
-func (e *RequiredNotSetError) Error() string {
-	return fmt.Sprintf("proto: required field %q not set", e.field)
-}
-
 var (
 	// errRepeatedHasNil is the error returned if Marshal is called with
 	// a struct with a repeated field containing a nil element.
@@ -82,10 +63,6 @@ var (
 
 const maxVarintBytes = 10 // maximum length of a varint
 
-// maxMarshalSize is the largest allowed size of an encoded protobuf,
-// since C++ and Java use signed int32s for the size.
-const maxMarshalSize = 1<<31 - 1
-
 // EncodeVarint returns the varint encoding of x.
 // This is the format for the
 // int32, int64, uint32, uint64, bool, and enum
@@ -119,18 +96,27 @@ func (p *Buffer) EncodeVarint(x uint64) error {
 
 // SizeVarint returns the varint encoding size of an integer.
 func SizeVarint(x uint64) int {
-	return sizeVarint(x)
-}
-
-func sizeVarint(x uint64) (n int) {
-	for {
-		n++
-		x >>= 7
-		if x == 0 {
-			break
-		}
-	}
-	return n
+	switch {
+	case x < 1<<7:
+		return 1
+	case x < 1<<14:
+		return 2
+	case x < 1<<21:
+		return 3
+	case x < 1<<28:
+		return 4
+	case x < 1<<35:
+		return 5
+	case x < 1<<42:
+		return 6
+	case x < 1<<49:
+		return 7
+	case x < 1<<56:
+		return 8
+	case x < 1<<63:
+		return 9
+	}
+	return 10
 }
 
 // EncodeFixed64 writes a 64-bit integer to the Buffer.
@@ -149,10 +135,6 @@ func (p *Buffer) EncodeFixed64(x uint64) error {
 	return nil
 }
 
-func sizeFixed64(x uint64) int {
-	return 8
-}
-
 // EncodeFixed32 writes a 32-bit integer to the Buffer.
 // This is the format for the
 // fixed32, sfixed32, and float protocol buffer types.
@@ -165,20 +147,12 @@ func (p *Buffer) EncodeFixed32(x uint64) error {
 	return nil
 }
 
-func sizeFixed32(x uint64) int {
-	return 4
-}
-
 // EncodeZigzag64 writes a zigzag-encoded 64-bit integer
 // to the Buffer.
 // This is the format used for the sint64 protocol buffer type.
 func (p *Buffer) EncodeZigzag64(x uint64) error {
 	// use signed number to get arithmetic right shift.
-	return p.EncodeVarint((x << 1) ^ uint64((int64(x) >> 63)))
-}
-
-func sizeZigzag64(x uint64) int {
-	return sizeVarint((x << 1) ^ uint64((int64(x) >> 63)))
+	return p.EncodeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
 }
 
 // EncodeZigzag32 writes a zigzag-encoded 32-bit integer
@@ -189,10 +163,6 @@ func (p *Buffer) EncodeZigzag32(x uint64) error {
 	return p.EncodeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
 }
 
-func sizeZigzag32(x uint64) int {
-	return sizeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
-}
-
 // EncodeRawBytes writes a count-delimited byte buffer to the Buffer.
 // This is the format used for the bytes protocol buffer
 // type and for embedded messages.
@@ -202,11 +172,6 @@ func (p *Buffer) EncodeRawBytes(b []byte) error {
 	return nil
 }
 
-func sizeRawBytes(b []byte) int {
-	return sizeVarint(uint64(len(b))) +
-		len(b)
-}
-
 // EncodeStringBytes writes an encoded string to the Buffer.
 // This is the format used for the proto2 string type.
 func (p *Buffer) EncodeStringBytes(s string) error {
@@ -215,319 +180,17 @@ func (p *Buffer) EncodeStringBytes(s string) error {
 	return nil
 }
 
-func sizeStringBytes(s string) int {
-	return sizeVarint(uint64(len(s))) +
-		len(s)
-}
-
 // Marshaler is the interface representing objects that can marshal themselves.
 type Marshaler interface {
 	Marshal() ([]byte, error)
 }
 
-// Marshal takes the protocol buffer
-// and encodes it into the wire format, returning the data.
-func Marshal(pb Message) ([]byte, error) {
-	// Can the object marshal itself?
-	if m, ok := pb.(Marshaler); ok {
-		return m.Marshal()
-	}
-	p := NewBuffer(nil)
-	err := p.Marshal(pb)
-	if p.buf == nil && err == nil {
-		// Return a non-nil slice on success.
-		return []byte{}, nil
-	}
-	return p.buf, err
-}
-
 // EncodeMessage writes the protocol buffer to the Buffer,
 // prefixed by a varint-encoded length.
 func (p *Buffer) EncodeMessage(pb Message) error {
-	t, base, err := getbase(pb)
-	if structPointer_IsNil(base) {
-		return ErrNil
-	}
-	if err == nil {
-		var state errorState
-		err = p.enc_len_struct(GetProperties(t.Elem()), base, &state)
-	}
-	return err
-}
-
-// Marshal takes the protocol buffer
-// and encodes it into the wire format, writing the result to the
-// Buffer.
-func (p *Buffer) Marshal(pb Message) error {
-	// Can the object marshal itself?
-	if m, ok := pb.(Marshaler); ok {
-		data, err := m.Marshal()
-		p.buf = append(p.buf, data...)
-		return err
-	}
-
-	t, base, err := getbase(pb)
-	if structPointer_IsNil(base) {
-		return ErrNil
-	}
-	if err == nil {
-		err = p.enc_struct(GetProperties(t.Elem()), base)
-	}
-
-	if collectStats {
-		(stats).Encode++ // Parens are to work around a goimports bug.
-	}
-
-	if len(p.buf) > maxMarshalSize {
-		return ErrTooLarge
-	}
-	return err
-}
-
-// Size returns the encoded size of a protocol buffer.
-func Size(pb Message) (n int) {
-	// Can the object marshal itself?  If so, Size is slow.
-	// TODO: add Size to Marshaler, or add a Sizer interface.
-	if m, ok := pb.(Marshaler); ok {
-		b, _ := m.Marshal()
-		return len(b)
-	}
-
-	t, base, err := getbase(pb)
-	if structPointer_IsNil(base) {
-		return 0
-	}
-	if err == nil {
-		n = size_struct(GetProperties(t.Elem()), base)
-	}
-
-	if collectStats {
-		(stats).Size++ // Parens are to work around a goimports bug.
-	}
-
-	return
-}
-
-// Individual type encoders.
-
-// Encode a bool.
-func (o *Buffer) enc_bool(p *Properties, base structPointer) error {
-	v := *structPointer_Bool(base, p.field)
-	if v == nil {
-		return ErrNil
-	}
-	x := 0
-	if *v {
-		x = 1
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, uint64(x))
-	return nil
-}
-
-func (o *Buffer) enc_proto3_bool(p *Properties, base structPointer) error {
-	v := *structPointer_BoolVal(base, p.field)
-	if !v {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, 1)
-	return nil
-}
-
-func size_bool(p *Properties, base structPointer) int {
-	v := *structPointer_Bool(base, p.field)
-	if v == nil {
-		return 0
-	}
-	return len(p.tagcode) + 1 // each bool takes exactly one byte
-}
-
-func size_proto3_bool(p *Properties, base structPointer) int {
-	v := *structPointer_BoolVal(base, p.field)
-	if !v && !p.oneof {
-		return 0
-	}
-	return len(p.tagcode) + 1 // each bool takes exactly one byte
-}
-
-// Encode an int32.
-func (o *Buffer) enc_int32(p *Properties, base structPointer) error {
-	v := structPointer_Word32(base, p.field)
-	if word32_IsNil(v) {
-		return ErrNil
-	}
-	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, uint64(x))
-	return nil
-}
-
-func (o *Buffer) enc_proto3_int32(p *Properties, base structPointer) error {
-	v := structPointer_Word32Val(base, p.field)
-	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
-	if x == 0 {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, uint64(x))
-	return nil
-}
-
-func size_int32(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word32(base, p.field)
-	if word32_IsNil(v) {
-		return 0
-	}
-	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
-	n += len(p.tagcode)
-	n += p.valSize(uint64(x))
-	return
-}
-
-func size_proto3_int32(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word32Val(base, p.field)
-	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
-	if x == 0 && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += p.valSize(uint64(x))
-	return
-}
-
-// Encode a uint32.
-// Exactly the same as int32, except for no sign extension.
-func (o *Buffer) enc_uint32(p *Properties, base structPointer) error {
-	v := structPointer_Word32(base, p.field)
-	if word32_IsNil(v) {
-		return ErrNil
-	}
-	x := word32_Get(v)
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, uint64(x))
-	return nil
-}
-
-func (o *Buffer) enc_proto3_uint32(p *Properties, base structPointer) error {
-	v := structPointer_Word32Val(base, p.field)
-	x := word32Val_Get(v)
-	if x == 0 {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, uint64(x))
-	return nil
-}
-
-func size_uint32(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word32(base, p.field)
-	if word32_IsNil(v) {
-		return 0
-	}
-	x := word32_Get(v)
-	n += len(p.tagcode)
-	n += p.valSize(uint64(x))
-	return
-}
-
-func size_proto3_uint32(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word32Val(base, p.field)
-	x := word32Val_Get(v)
-	if x == 0 && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += p.valSize(uint64(x))
-	return
-}
-
-// Encode an int64.
-func (o *Buffer) enc_int64(p *Properties, base structPointer) error {
-	v := structPointer_Word64(base, p.field)
-	if word64_IsNil(v) {
-		return ErrNil
-	}
-	x := word64_Get(v)
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, x)
-	return nil
-}
-
-func (o *Buffer) enc_proto3_int64(p *Properties, base structPointer) error {
-	v := structPointer_Word64Val(base, p.field)
-	x := word64Val_Get(v)
-	if x == 0 {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	p.valEnc(o, x)
-	return nil
-}
-
-func size_int64(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word64(base, p.field)
-	if word64_IsNil(v) {
-		return 0
-	}
-	x := word64_Get(v)
-	n += len(p.tagcode)
-	n += p.valSize(x)
-	return
-}
-
-func size_proto3_int64(p *Properties, base structPointer) (n int) {
-	v := structPointer_Word64Val(base, p.field)
-	x := word64Val_Get(v)
-	if x == 0 && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += p.valSize(x)
-	return
-}
-
-// Encode a string.
-func (o *Buffer) enc_string(p *Properties, base structPointer) error {
-	v := *structPointer_String(base, p.field)
-	if v == nil {
-		return ErrNil
-	}
-	x := *v
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeStringBytes(x)
-	return nil
-}
-
-func (o *Buffer) enc_proto3_string(p *Properties, base structPointer) error {
-	v := *structPointer_StringVal(base, p.field)
-	if v == "" {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeStringBytes(v)
-	return nil
-}
-
-func size_string(p *Properties, base structPointer) (n int) {
-	v := *structPointer_String(base, p.field)
-	if v == nil {
-		return 0
-	}
-	x := *v
-	n += len(p.tagcode)
-	n += sizeStringBytes(x)
-	return
-}
-
-func size_proto3_string(p *Properties, base structPointer) (n int) {
-	v := *structPointer_StringVal(base, p.field)
-	if v == "" && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += sizeStringBytes(v)
-	return
+	siz := Size(pb)
+	p.EncodeVarint(uint64(siz))
+	return p.Marshal(pb)
 }
 
 // All protocol buffer fields are nillable, but be careful.
@@ -538,825 +201,3 @@ func isNil(v reflect.Value) bool {
 	}
 	return false
 }
-
-// Encode a message struct.
-func (o *Buffer) enc_struct_message(p *Properties, base structPointer) error {
-	var state errorState
-	structp := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(structp) {
-		return ErrNil
-	}
-
-	// Can the object marshal itself?
-	if p.isMarshaler {
-		m := structPointer_Interface(structp, p.stype).(Marshaler)
-		data, err := m.Marshal()
-		if err != nil && !state.shouldContinue(err, nil) {
-			return err
-		}
-		o.buf = append(o.buf, p.tagcode...)
-		o.EncodeRawBytes(data)
-		return state.err
-	}
-
-	o.buf = append(o.buf, p.tagcode...)
-	return o.enc_len_struct(p.sprop, structp, &state)
-}
-
-func size_struct_message(p *Properties, base structPointer) int {
-	structp := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(structp) {
-		return 0
-	}
-
-	// Can the object marshal itself?
-	if p.isMarshaler {
-		m := structPointer_Interface(structp, p.stype).(Marshaler)
-		data, _ := m.Marshal()
-		n0 := len(p.tagcode)
-		n1 := sizeRawBytes(data)
-		return n0 + n1
-	}
-
-	n0 := len(p.tagcode)
-	n1 := size_struct(p.sprop, structp)
-	n2 := sizeVarint(uint64(n1)) // size of encoded length
-	return n0 + n1 + n2
-}
-
-// Encode a group struct.
-func (o *Buffer) enc_struct_group(p *Properties, base structPointer) error {
-	var state errorState
-	b := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(b) {
-		return ErrNil
-	}
-
-	o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
-	err := o.enc_struct(p.sprop, b)
-	if err != nil && !state.shouldContinue(err, nil) {
-		return err
-	}
-	o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
-	return state.err
-}
-
-func size_struct_group(p *Properties, base structPointer) (n int) {
-	b := structPointer_GetStructPointer(base, p.field)
-	if structPointer_IsNil(b) {
-		return 0
-	}
-
-	n += sizeVarint(uint64((p.Tag << 3) | WireStartGroup))
-	n += size_struct(p.sprop, b)
-	n += sizeVarint(uint64((p.Tag << 3) | WireEndGroup))
-	return
-}
-
-// Encode a slice of bools ([]bool).
-func (o *Buffer) enc_slice_bool(p *Properties, base structPointer) error {
-	s := *structPointer_BoolSlice(base, p.field)
-	l := len(s)
-	if l == 0 {
-		return ErrNil
-	}
-	for _, x := range s {
-		o.buf = append(o.buf, p.tagcode...)
-		v := uint64(0)
-		if x {
-			v = 1
-		}
-		p.valEnc(o, v)
-	}
-	return nil
-}
-
-func size_slice_bool(p *Properties, base structPointer) int {
-	s := *structPointer_BoolSlice(base, p.field)
-	l := len(s)
-	if l == 0 {
-		return 0
-	}
-	return l * (len(p.tagcode) + 1) // each bool takes exactly one byte
-}
-
-// Encode a slice of bools ([]bool) in packed format.
-func (o *Buffer) enc_slice_packed_bool(p *Properties, base structPointer) error {
-	s := *structPointer_BoolSlice(base, p.field)
-	l := len(s)
-	if l == 0 {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeVarint(uint64(l)) // each bool takes exactly one byte
-	for _, x := range s {
-		v := uint64(0)
-		if x {
-			v = 1
-		}
-		p.valEnc(o, v)
-	}
-	return nil
-}
-
-func size_slice_packed_bool(p *Properties, base structPointer) (n int) {
-	s := *structPointer_BoolSlice(base, p.field)
-	l := len(s)
-	if l == 0 {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += sizeVarint(uint64(l))
-	n += l // each bool takes exactly one byte
-	return
-}
-
-// Encode a slice of bytes ([]byte).
-func (o *Buffer) enc_slice_byte(p *Properties, base structPointer) error {
-	s := *structPointer_Bytes(base, p.field)
-	if s == nil {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeRawBytes(s)
-	return nil
-}
-
-func (o *Buffer) enc_proto3_slice_byte(p *Properties, base structPointer) error {
-	s := *structPointer_Bytes(base, p.field)
-	if len(s) == 0 {
-		return ErrNil
-	}
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeRawBytes(s)
-	return nil
-}
-
-func size_slice_byte(p *Properties, base structPointer) (n int) {
-	s := *structPointer_Bytes(base, p.field)
-	if s == nil && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += sizeRawBytes(s)
-	return
-}
-
-func size_proto3_slice_byte(p *Properties, base structPointer) (n int) {
-	s := *structPointer_Bytes(base, p.field)
-	if len(s) == 0 && !p.oneof {
-		return 0
-	}
-	n += len(p.tagcode)
-	n += sizeRawBytes(s)
-	return
-}
-
-// Encode a slice of int32s ([]int32).
-func (o *Buffer) enc_slice_int32(p *Properties, base structPointer) error {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	for i := 0; i < l; i++ {
-		o.buf = append(o.buf, p.tagcode...)
-		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
-		p.valEnc(o, uint64(x))
-	}
-	return nil
-}
-
-func size_slice_int32(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	for i := 0; i < l; i++ {
-		n += len(p.tagcode)
-		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
-		n += p.valSize(uint64(x))
-	}
-	return
-}
-
-// Encode a slice of int32s ([]int32) in packed format.
-func (o *Buffer) enc_slice_packed_int32(p *Properties, base structPointer) error {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	// TODO: Reuse a Buffer.
-	buf := NewBuffer(nil)
-	for i := 0; i < l; i++ {
-		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
-		p.valEnc(buf, uint64(x))
-	}
-
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeVarint(uint64(len(buf.buf)))
-	o.buf = append(o.buf, buf.buf...)
-	return nil
-}
-
-func size_slice_packed_int32(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	var bufSize int
-	for i := 0; i < l; i++ {
-		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
-		bufSize += p.valSize(uint64(x))
-	}
-
-	n += len(p.tagcode)
-	n += sizeVarint(uint64(bufSize))
-	n += bufSize
-	return
-}
-
-// Encode a slice of uint32s ([]uint32).
-// Exactly the same as int32, except for no sign extension.
-func (o *Buffer) enc_slice_uint32(p *Properties, base structPointer) error {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	for i := 0; i < l; i++ {
-		o.buf = append(o.buf, p.tagcode...)
-		x := s.Index(i)
-		p.valEnc(o, uint64(x))
-	}
-	return nil
-}
-
-func size_slice_uint32(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	for i := 0; i < l; i++ {
-		n += len(p.tagcode)
-		x := s.Index(i)
-		n += p.valSize(uint64(x))
-	}
-	return
-}
-
-// Encode a slice of uint32s ([]uint32) in packed format.
-// Exactly the same as int32, except for no sign extension.
-func (o *Buffer) enc_slice_packed_uint32(p *Properties, base structPointer) error {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	// TODO: Reuse a Buffer.
-	buf := NewBuffer(nil)
-	for i := 0; i < l; i++ {
-		p.valEnc(buf, uint64(s.Index(i)))
-	}
-
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeVarint(uint64(len(buf.buf)))
-	o.buf = append(o.buf, buf.buf...)
-	return nil
-}
-
-func size_slice_packed_uint32(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word32Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	var bufSize int
-	for i := 0; i < l; i++ {
-		bufSize += p.valSize(uint64(s.Index(i)))
-	}
-
-	n += len(p.tagcode)
-	n += sizeVarint(uint64(bufSize))
-	n += bufSize
-	return
-}
-
-// Encode a slice of int64s ([]int64).
-func (o *Buffer) enc_slice_int64(p *Properties, base structPointer) error {
-	s := structPointer_Word64Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	for i := 0; i < l; i++ {
-		o.buf = append(o.buf, p.tagcode...)
-		p.valEnc(o, s.Index(i))
-	}
-	return nil
-}
-
-func size_slice_int64(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word64Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	for i := 0; i < l; i++ {
-		n += len(p.tagcode)
-		n += p.valSize(s.Index(i))
-	}
-	return
-}
-
-// Encode a slice of int64s ([]int64) in packed format.
-func (o *Buffer) enc_slice_packed_int64(p *Properties, base structPointer) error {
-	s := structPointer_Word64Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return ErrNil
-	}
-	// TODO: Reuse a Buffer.
-	buf := NewBuffer(nil)
-	for i := 0; i < l; i++ {
-		p.valEnc(buf, s.Index(i))
-	}
-
-	o.buf = append(o.buf, p.tagcode...)
-	o.EncodeVarint(uint64(len(buf.buf)))
-	o.buf = append(o.buf, buf.buf...)
-	return nil
-}
-
-func size_slice_packed_int64(p *Properties, base structPointer) (n int) {
-	s := structPointer_Word64Slice(base, p.field)
-	l := s.Len()
-	if l == 0 {
-		return 0
-	}
-	var bufSize int
-	for i := 0; i < l; i++ {
-		bufSize += p.valSize(s.Index(i))
-	}
-
-	n += len(p.tagcode)
-	n += sizeVarint(uint64(bufSize))
-	n += bufSize
-	return
-}
-
-// Encode a slice of slice of bytes ([][]byte).
-func (o *Buffer) enc_slice_slice_byte(p *Properties, base structPointer) error {
-	ss := *structPointer_BytesSlice(base, p.field)
-	l := len(ss)
-	if l == 0 {
-		return ErrNil
-	}
-	for i := 0; i < l; i++ {
-		o.buf = append(o.buf, p.tagcode...)
-		o.EncodeRawBytes(ss[i])
-	}
-	return nil
-}
-
-func size_slice_slice_byte(p *Properties, base structPointer) (n int) {
-	ss := *structPointer_BytesSlice(base, p.field)
-	l := len(ss)
-	if l == 0 {
-		return 0
-	}
-	n += l * len(p.tagcode)
-	for i := 0; i < l; i++ {
-		n += sizeRawBytes(ss[i])
-	}
-	return
-}
-
-// Encode a slice of strings ([]string).
-func (o *Buffer) enc_slice_string(p *Properties, base structPointer) error {
-	ss := *structPointer_StringSlice(base, p.field)
-	l := len(ss)
-	for i := 0; i < l; i++ {
-		o.buf = append(o.buf, p.tagcode...)
-		o.EncodeStringBytes(ss[i])
-	}
-	return nil
-}
-
-func size_slice_string(p *Properties, base structPointer) (n int) {
-	ss := *structPointer_StringSlice(base, p.field)
-	l := len(ss)
-	n += l * len(p.tagcode)
-	for i := 0; i < l; i++ {
-		n += sizeStringBytes(ss[i])
-	}
-	return
-}
-
-// Encode a slice of message structs ([]*struct).
-func (o *Buffer) enc_slice_struct_message(p *Properties, base structPointer) error {
-	var state errorState
-	s := structPointer_StructPointerSlice(base, p.field)
-	l := s.Len()
-
-	for i := 0; i < l; i++ {
-		structp := s.Index(i)
-		if structPointer_IsNil(structp) {
-			return errRepeatedHasNil
-		}
-
-		// Can the object marshal itself?
-		if p.isMarshaler {
-			m := structPointer_Interface(structp, p.stype).(Marshaler)
-			data, err := m.Marshal()
-			if err != nil && !state.shouldContinue(err, nil) {
-				return err
-			}
-			o.buf = append(o.buf, p.tagcode...)
-			o.EncodeRawBytes(data)
-			continue
-		}
-
-		o.buf = append(o.buf, p.tagcode...)
-		err := o.enc_len_struct(p.sprop, structp, &state)
-		if err != nil && !state.shouldContinue(err, nil) {
-			if err == ErrNil {
-				return errRepeatedHasNil
-			}
-			return err
-		}
-	}
-	return state.err
-}
-
-func size_slice_struct_message(p *Properties, base structPointer) (n int) {
-	s := structPointer_StructPointerSlice(base, p.field)
-	l := s.Len()
-	n += l * len(p.tagcode)
-	for i := 0; i < l; i++ {
-		structp := s.Index(i)
-		if structPointer_IsNil(structp) {
-			return // return the size up to this point
-		}
-
-		// Can the object marshal itself?
-		if p.isMarshaler {
-			m := structPointer_Interface(structp, p.stype).(Marshaler)
-			data, _ := m.Marshal()
-			n += sizeRawBytes(data)
-			continue
-		}
-
-		n0 := size_struct(p.sprop, structp)
-		n1 := sizeVarint(uint64(n0)) // size of encoded length
-		n += n0 + n1
-	}
-	return
-}
-
-// Encode a slice of group structs ([]*struct).
-func (o *Buffer) enc_slice_struct_group(p *Properties, base structPointer) error {
-	var state errorState
-	s := structPointer_StructPointerSlice(base, p.field)
-	l := s.Len()
-
-	for i := 0; i < l; i++ {
-		b := s.Index(i)
-		if structPointer_IsNil(b) {
-			return errRepeatedHasNil
-		}
-
-		o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
-
-		err := o.enc_struct(p.sprop, b)
-
-		if err != nil && !state.shouldContinue(err, nil) {
-			if err == ErrNil {
-				return errRepeatedHasNil
-			}
-			return err
-		}
-
-		o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
-	}
-	return state.err
-}
-
-func size_slice_struct_group(p *Properties, base structPointer) (n int) {
-	s := structPointer_StructPointerSlice(base, p.field)
-	l := s.Len()
-
-	n += l * sizeVarint(uint64((p.Tag<<3)|WireStartGroup))
-	n += l * sizeVarint(uint64((p.Tag<<3)|WireEndGroup))
-	for i := 0; i < l; i++ {
-		b := s.Index(i)
-		if structPointer_IsNil(b) {
-			return // return size up to this point
-		}
-
-		n += size_struct(p.sprop, b)
-	}
-	return
-}
-
-// Encode an extension map.
-func (o *Buffer) enc_map(p *Properties, base structPointer) error {
-	exts := structPointer_ExtMap(base, p.field)
-	if err := encodeExtensionsMap(*exts); err != nil {
-		return err
-	}
-
-	return o.enc_map_body(*exts)
-}
-
-func (o *Buffer) enc_exts(p *Properties, base structPointer) error {
-	exts := structPointer_Extensions(base, p.field)
-
-	v, mu := exts.extensionsRead()
-	if v == nil {
-		return nil
-	}
-
-	mu.Lock()
-	defer mu.Unlock()
-	if err := encodeExtensionsMap(v); err != nil {
-		return err
-	}
-
-	return o.enc_map_body(v)
-}
-
-func (o *Buffer) enc_map_body(v map[int32]Extension) error {
-	// Fast-path for common cases: zero or one extensions.
-	if len(v) <= 1 {
-		for _, e := range v {
-			o.buf = append(o.buf, e.enc...)
-		}
-		return nil
-	}
-
-	// Sort keys to provide a deterministic encoding.
-	keys := make([]int, 0, len(v))
-	for k := range v {
-		keys = append(keys, int(k))
-	}
-	sort.Ints(keys)
-
-	for _, k := range keys {
-		o.buf = append(o.buf, v[int32(k)].enc...)
-	}
-	return nil
-}
-
-func size_map(p *Properties, base structPointer) int {
-	v := structPointer_ExtMap(base, p.field)
-	return extensionsMapSize(*v)
-}
-
-func size_exts(p *Properties, base structPointer) int {
-	v := structPointer_Extensions(base, p.field)
-	return extensionsSize(v)
-}
-
-// Encode a map field.
-func (o *Buffer) enc_new_map(p *Properties, base structPointer) error {
-	var state errorState // XXX: or do we need to plumb this through?
-
-	/*
-		A map defined as
-			map<key_type, value_type> map_field = N;
-		is encoded in the same way as
-			message MapFieldEntry {
-				key_type key = 1;
-				value_type value = 2;
-			}
-			repeated MapFieldEntry map_field = N;
-	*/
-
-	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
-	if v.Len() == 0 {
-		return nil
-	}
-
-	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
-
-	enc := func() error {
-		if err := p.mkeyprop.enc(o, p.mkeyprop, keybase); err != nil {
-			return err
-		}
-		if err := p.mvalprop.enc(o, p.mvalprop, valbase); err != nil && err != ErrNil {
-			return err
-		}
-		return nil
-	}
-
-	// Don't sort map keys. It is not required by the spec, and C++ doesn't do it.
-	for _, key := range v.MapKeys() {
-		val := v.MapIndex(key)
-
-		keycopy.Set(key)
-		valcopy.Set(val)
-
-		o.buf = append(o.buf, p.tagcode...)
-		if err := o.enc_len_thing(enc, &state); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func size_new_map(p *Properties, base structPointer) int {
-	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
-
-	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
-
-	n := 0
-	for _, key := range v.MapKeys() {
-		val := v.MapIndex(key)
-		keycopy.Set(key)
-		valcopy.Set(val)
-
-		// Tag codes for key and val are the responsibility of the sub-sizer.
-		keysize := p.mkeyprop.size(p.mkeyprop, keybase)
-		valsize := p.mvalprop.size(p.mvalprop, valbase)
-		entry := keysize + valsize
-		// Add on tag code and length of map entry itself.
-		n += len(p.tagcode) + sizeVarint(uint64(entry)) + entry
-	}
-	return n
-}
-
-// mapEncodeScratch returns a new reflect.Value matching the map's value type,
-// and a structPointer suitable for passing to an encoder or sizer.
-func mapEncodeScratch(mapType reflect.Type) (keycopy, valcopy reflect.Value, keybase, valbase structPointer) {
-	// Prepare addressable doubly-indirect placeholders for the key and value types.
-	// This is needed because the element-type encoders expect **T, but the map iteration produces T.
-
-	keycopy = reflect.New(mapType.Key()).Elem()                 // addressable K
-	keyptr := reflect.New(reflect.PtrTo(keycopy.Type())).Elem() // addressable *K
-	keyptr.Set(keycopy.Addr())                                  //
-	keybase = toStructPointer(keyptr.Addr())                    // **K
-
-	// Value types are more varied and require special handling.
-	switch mapType.Elem().Kind() {
-	case reflect.Slice:
-		// []byte
-		var dummy []byte
-		valcopy = reflect.ValueOf(&dummy).Elem() // addressable []byte
-		valbase = toStructPointer(valcopy.Addr())
-	case reflect.Ptr:
-		// message; the generated field type is map[K]*Msg (so V is *Msg),
-		// so we only need one level of indirection.
-		valcopy = reflect.New(mapType.Elem()).Elem() // addressable V
-		valbase = toStructPointer(valcopy.Addr())
-	default:
-		// everything else
-		valcopy = reflect.New(mapType.Elem()).Elem()                // addressable V
-		valptr := reflect.New(reflect.PtrTo(valcopy.Type())).Elem() // addressable *V
-		valptr.Set(valcopy.Addr())                                  //
-		valbase = toStructPointer(valptr.Addr())                    // **V
-	}
-	return
-}
-
-// Encode a struct.
-func (o *Buffer) enc_struct(prop *StructProperties, base structPointer) error {
-	var state errorState
-	// Encode fields in tag order so that decoders may use optimizations
-	// that depend on the ordering.
-	// https://developers.google.com/protocol-buffers/docs/encoding#order
-	for _, i := range prop.order {
-		p := prop.Prop[i]
-		if p.enc != nil {
-			err := p.enc(o, p, base)
-			if err != nil {
-				if err == ErrNil {
-					if p.Required && state.err == nil {
-						state.err = &RequiredNotSetError{p.Name}
-					}
-				} else if err == errRepeatedHasNil {
-					// Give more context to nil values in repeated fields.
-					return errors.New("repeated field " + p.OrigName + " has nil element")
-				} else if !state.shouldContinue(err, p) {
-					return err
-				}
-			}
-			if len(o.buf) > maxMarshalSize {
-				return ErrTooLarge
-			}
-		}
-	}
-
-	// Do oneof fields.
-	if prop.oneofMarshaler != nil {
-		m := structPointer_Interface(base, prop.stype).(Message)
-		if err := prop.oneofMarshaler(m, o); err == ErrNil {
-			return errOneofHasNil
-		} else if err != nil {
-			return err
-		}
-	}
-
-	// Add unrecognized fields at the end.
-	if prop.unrecField.IsValid() {
-		v := *structPointer_Bytes(base, prop.unrecField)
-		if len(o.buf)+len(v) > maxMarshalSize {
-			return ErrTooLarge
-		}
-		if len(v) > 0 {
-			o.buf = append(o.buf, v...)
-		}
-	}
-
-	return state.err
-}
-
-func size_struct(prop *StructProperties, base structPointer) (n int) {
-	for _, i := range prop.order {
-		p := prop.Prop[i]
-		if p.size != nil {
-			n += p.size(p, base)
-		}
-	}
-
-	// Add unrecognized fields at the end.
-	if prop.unrecField.IsValid() {
-		v := *structPointer_Bytes(base, prop.unrecField)
-		n += len(v)
-	}
-
-	// Factor in any oneof fields.
-	if prop.oneofSizer != nil {
-		m := structPointer_Interface(base, prop.stype).(Message)
-		n += prop.oneofSizer(m)
-	}
-
-	return
-}
-
-var zeroes [20]byte // longer than any conceivable sizeVarint
-
-// Encode a struct, preceded by its encoded length (as a varint).
-func (o *Buffer) enc_len_struct(prop *StructProperties, base structPointer, state *errorState) error {
-	return o.enc_len_thing(func() error { return o.enc_struct(prop, base) }, state)
-}
-
-// Encode something, preceded by its encoded length (as a varint).
-func (o *Buffer) enc_len_thing(enc func() error, state *errorState) error {
-	iLen := len(o.buf)
-	o.buf = append(o.buf, 0, 0, 0, 0) // reserve four bytes for length
-	iMsg := len(o.buf)
-	err := enc()
-	if err != nil && !state.shouldContinue(err, nil) {
-		return err
-	}
-	lMsg := len(o.buf) - iMsg
-	lLen := sizeVarint(uint64(lMsg))
-	switch x := lLen - (iMsg - iLen); {
-	case x > 0: // actual length is x bytes larger than the space we reserved
-		// Move msg x bytes right.
-		o.buf = append(o.buf, zeroes[:x]...)
-		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
-	case x < 0: // actual length is x bytes smaller than the space we reserved
-		// Move msg x bytes left.
-		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
-		o.buf = o.buf[:len(o.buf)+x] // x is negative
-	}
-	// Encode the length in the reserved space.
-	o.buf = o.buf[:iLen]
-	o.EncodeVarint(uint64(lMsg))
-	o.buf = o.buf[:len(o.buf)+lMsg]
-	return state.err
-}
-
-// errorState maintains the first error that occurs and updates that error
-// with additional context.
-type errorState struct {
-	err error
-}
-
-// shouldContinue reports whether encoding should continue upon encountering the
-// given error. If the error is RequiredNotSetError, shouldContinue returns true
-// and, if this is the first appearance of that error, remembers it for future
-// reporting.
-//
-// If prop is not nil, it may update any error with additional context about the
-// field with the error.
-func (s *errorState) shouldContinue(err error, prop *Properties) bool {
-	// Ignore unset required fields.
-	reqNotSet, ok := err.(*RequiredNotSetError)
-	if !ok {
-		return false
-	}
-	if s.err == nil {
-		if prop != nil {
-			err = &RequiredNotSetError{prop.Name + "." + reqNotSet.field}
-		}
-		s.err = err
-	}
-	return true
-}
diff --git a/vendor/github.com/golang/protobuf/proto/equal.go b/vendor/github.com/golang/protobuf/proto/equal.go
index 2ed1cf5966..f9b6e41b3c 100644
--- a/vendor/github.com/golang/protobuf/proto/equal.go
+++ b/vendor/github.com/golang/protobuf/proto/equal.go
@@ -109,15 +109,6 @@ func equalStruct(v1, v2 reflect.Value) bool {
 				// set/unset mismatch
 				return false
 			}
-			b1, ok := f1.Interface().(raw)
-			if ok {
-				b2 := f2.Interface().(raw)
-				// RawMessage
-				if !bytes.Equal(b1.Bytes(), b2.Bytes()) {
-					return false
-				}
-				continue
-			}
 			f1, f2 = f1.Elem(), f2.Elem()
 		}
 		if !equalAny(f1, f2, sprop.Prop[i]) {
@@ -146,11 +137,7 @@ func equalStruct(v1, v2 reflect.Value) bool {
 
 	u1 := uf.Bytes()
 	u2 := v2.FieldByName("XXX_unrecognized").Bytes()
-	if !bytes.Equal(u1, u2) {
-		return false
-	}
-
-	return true
+	return bytes.Equal(u1, u2)
 }
 
 // v1 and v2 are known to have the same type.
@@ -259,7 +246,17 @@ func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
 			return false
 		}
 
-		m1, m2 := e1.value, e2.value
+		m1 := extensionAsLegacyType(e1.value)
+		m2 := extensionAsLegacyType(e2.value)
+
+		if m1 == nil && m2 == nil {
+			// Both have only encoded form.
+			if bytes.Equal(e1.enc, e2.enc) {
+				continue
+			}
+			// The bytes are different, but the extensions might still be
+			// equal. We need to decode them to compare.
+		}
 
 		if m1 != nil && m2 != nil {
 			// Both are unencoded.
@@ -276,8 +273,12 @@ func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
 			desc = m[extNum]
 		}
 		if desc == nil {
+			// If both have only encoded form and the bytes are the same,
+			// it is handled above. We get here when the bytes are different.
+			// We don't know how to decode it, so just compare them as byte
+			// slices.
 			log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
-			continue
+			return false
 		}
 		var err error
 		if m1 == nil {
diff --git a/vendor/github.com/golang/protobuf/proto/extensions.go b/vendor/github.com/golang/protobuf/proto/extensions.go
index eaad218312..fa88add30a 100644
--- a/vendor/github.com/golang/protobuf/proto/extensions.go
+++ b/vendor/github.com/golang/protobuf/proto/extensions.go
@@ -38,6 +38,7 @@ package proto
 import (
 	"errors"
 	"fmt"
+	"io"
 	"reflect"
 	"strconv"
 	"sync"
@@ -91,14 +92,29 @@ func (n notLocker) Unlock() {}
 // extendable returns the extendableProto interface for the given generated proto message.
 // If the proto message has the old extension format, it returns a wrapper that implements
 // the extendableProto interface.
-func extendable(p interface{}) (extendableProto, bool) {
-	if ep, ok := p.(extendableProto); ok {
-		return ep, ok
-	}
-	if ep, ok := p.(extendableProtoV1); ok {
-		return extensionAdapter{ep}, ok
+func extendable(p interface{}) (extendableProto, error) {
+	switch p := p.(type) {
+	case extendableProto:
+		if isNilPtr(p) {
+			return nil, fmt.Errorf("proto: nil %T is not extendable", p)
+		}
+		return p, nil
+	case extendableProtoV1:
+		if isNilPtr(p) {
+			return nil, fmt.Errorf("proto: nil %T is not extendable", p)
+		}
+		return extensionAdapter{p}, nil
 	}
-	return nil, false
+	// Don't allocate a specific error containing %T:
+	// this is the hot path for Clone and MarshalText.
+	return nil, errNotExtendable
+}
+
+var errNotExtendable = errors.New("proto: not an extendable proto.Message")
+
+func isNilPtr(x interface{}) bool {
+	v := reflect.ValueOf(x)
+	return v.Kind() == reflect.Ptr && v.IsNil()
 }
 
 // XXX_InternalExtensions is an internal representation of proto extensions.
@@ -143,9 +159,6 @@ func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Loc
 	return e.p.extensionMap, &e.p.mu
 }
 
-var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
-var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem()
-
 // ExtensionDesc represents an extension specification.
 // Used in generated code from the protocol compiler.
 type ExtensionDesc struct {
@@ -172,15 +185,31 @@ type Extension struct {
 	// extension will have only enc set. When such an extension is
 	// accessed using GetExtension (or GetExtensions) desc and value
 	// will be set.
-	desc  *ExtensionDesc
+	desc *ExtensionDesc
+
+	// value is a concrete value for the extension field. Let the type of
+	// desc.ExtensionType be the "API type" and the type of Extension.value
+	// be the "storage type". The API type and storage type are the same except:
+	//	* For scalars (except []byte), the API type uses *T,
+	//	while the storage type uses T.
+	//	* For repeated fields, the API type uses []T, while the storage type
+	//	uses *[]T.
+	//
+	// The reason for the divergence is so that the storage type more naturally
+	// matches what is expected of when retrieving the values through the
+	// protobuf reflection APIs.
+	//
+	// The value may only be populated if desc is also populated.
 	value interface{}
-	enc   []byte
+
+	// enc is the raw bytes for the extension field.
+	enc []byte
 }
 
 // SetRawExtension is for testing only.
 func SetRawExtension(base Message, id int32, b []byte) {
-	epb, ok := extendable(base)
-	if !ok {
+	epb, err := extendable(base)
+	if err != nil {
 		return
 	}
 	extmap := epb.extensionsWrite()
@@ -205,7 +234,7 @@ func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
 		pbi = ea.extendableProtoV1
 	}
 	if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b {
-		return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String())
+		return fmt.Errorf("proto: bad extended type; %v does not extend %v", b, a)
 	}
 	// Check the range.
 	if !isExtensionField(pb, extension.Field) {
@@ -250,85 +279,11 @@ func extensionProperties(ed *ExtensionDesc) *Properties {
 	return prop
 }
 
-// encode encodes any unmarshaled (unencoded) extensions in e.
-func encodeExtensions(e *XXX_InternalExtensions) error {
-	m, mu := e.extensionsRead()
-	if m == nil {
-		return nil // fast path
-	}
-	mu.Lock()
-	defer mu.Unlock()
-	return encodeExtensionsMap(m)
-}
-
-// encode encodes any unmarshaled (unencoded) extensions in e.
-func encodeExtensionsMap(m map[int32]Extension) error {
-	for k, e := range m {
-		if e.value == nil || e.desc == nil {
-			// Extension is only in its encoded form.
-			continue
-		}
-
-		// We don't skip extensions that have an encoded form set,
-		// because the extension value may have been mutated after
-		// the last time this function was called.
-
-		et := reflect.TypeOf(e.desc.ExtensionType)
-		props := extensionProperties(e.desc)
-
-		p := NewBuffer(nil)
-		// If e.value has type T, the encoder expects a *struct{ X T }.
-		// Pass a *T with a zero field and hope it all works out.
-		x := reflect.New(et)
-		x.Elem().Set(reflect.ValueOf(e.value))
-		if err := props.enc(p, props, toStructPointer(x)); err != nil {
-			return err
-		}
-		e.enc = p.buf
-		m[k] = e
-	}
-	return nil
-}
-
-func extensionsSize(e *XXX_InternalExtensions) (n int) {
-	m, mu := e.extensionsRead()
-	if m == nil {
-		return 0
-	}
-	mu.Lock()
-	defer mu.Unlock()
-	return extensionsMapSize(m)
-}
-
-func extensionsMapSize(m map[int32]Extension) (n int) {
-	for _, e := range m {
-		if e.value == nil || e.desc == nil {
-			// Extension is only in its encoded form.
-			n += len(e.enc)
-			continue
-		}
-
-		// We don't skip extensions that have an encoded form set,
-		// because the extension value may have been mutated after
-		// the last time this function was called.
-
-		et := reflect.TypeOf(e.desc.ExtensionType)
-		props := extensionProperties(e.desc)
-
-		// If e.value has type T, the encoder expects a *struct{ X T }.
-		// Pass a *T with a zero field and hope it all works out.
-		x := reflect.New(et)
-		x.Elem().Set(reflect.ValueOf(e.value))
-		n += props.size(props, toStructPointer(x))
-	}
-	return
-}
-
 // HasExtension returns whether the given extension is present in pb.
 func HasExtension(pb Message, extension *ExtensionDesc) bool {
 	// TODO: Check types, field numbers, etc.?
-	epb, ok := extendable(pb)
-	if !ok {
+	epb, err := extendable(pb)
+	if err != nil {
 		return false
 	}
 	extmap, mu := epb.extensionsRead()
@@ -336,15 +291,15 @@ func HasExtension(pb Message, extension *ExtensionDesc) bool {
 		return false
 	}
 	mu.Lock()
-	_, ok = extmap[extension.Field]
+	_, ok := extmap[extension.Field]
 	mu.Unlock()
 	return ok
 }
 
 // ClearExtension removes the given extension from pb.
 func ClearExtension(pb Message, extension *ExtensionDesc) {
-	epb, ok := extendable(pb)
-	if !ok {
+	epb, err := extendable(pb)
+	if err != nil {
 		return
 	}
 	// TODO: Check types, field numbers, etc.?
@@ -352,16 +307,26 @@ func ClearExtension(pb Message, extension *ExtensionDesc) {
 	delete(extmap, extension.Field)
 }
 
-// GetExtension parses and returns the given extension of pb.
-// If the extension is not present and has no default value it returns ErrMissingExtension.
+// GetExtension retrieves a proto2 extended field from pb.
+//
+// If the descriptor is type complete (i.e., ExtensionDesc.ExtensionType is non-nil),
+// then GetExtension parses the encoded field and returns a Go value of the specified type.
+// If the field is not present, then the default value is returned (if one is specified),
+// otherwise ErrMissingExtension is reported.
+//
+// If the descriptor is not type complete (i.e., ExtensionDesc.ExtensionType is nil),
+// then GetExtension returns the raw encoded bytes of the field extension.
 func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
-	epb, ok := extendable(pb)
-	if !ok {
-		return nil, errors.New("proto: not an extendable proto")
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
 	}
 
-	if err := checkExtensionTypes(epb, extension); err != nil {
-		return nil, err
+	if extension.ExtendedType != nil {
+		// can only check type if this is a complete descriptor
+		if err := checkExtensionTypes(epb, extension); err != nil {
+			return nil, err
+		}
 	}
 
 	emap, mu := epb.extensionsRead()
@@ -385,7 +350,12 @@ func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
 			// descriptors with the same field number.
 			return nil, errors.New("proto: descriptor conflict")
 		}
-		return e.value, nil
+		return extensionAsLegacyType(e.value), nil
+	}
+
+	if extension.ExtensionType == nil {
+		// incomplete descriptor
+		return e.enc, nil
 	}
 
 	v, err := decodeExtension(e.enc, extension)
@@ -395,16 +365,21 @@ func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
 
 	// Remember the decoded version and drop the encoded version.
 	// That way it is safe to mutate what we return.
-	e.value = v
+	e.value = extensionAsStorageType(v)
 	e.desc = extension
 	e.enc = nil
 	emap[extension.Field] = e
-	return e.value, nil
+	return extensionAsLegacyType(e.value), nil
 }
 
 // defaultExtensionValue returns the default value for extension.
 // If no default for an extension is defined ErrMissingExtension is returned.
 func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
+	if extension.ExtensionType == nil {
+		// incomplete descriptor, so no default
+		return nil, ErrMissingExtension
+	}
+
 	t := reflect.TypeOf(extension.ExtensionType)
 	props := extensionProperties(extension)
 
@@ -439,31 +414,28 @@ func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
 
 // decodeExtension decodes an extension encoded in b.
 func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
-	o := NewBuffer(b)
-
 	t := reflect.TypeOf(extension.ExtensionType)
-
-	props := extensionProperties(extension)
+	unmarshal := typeUnmarshaler(t, extension.Tag)
 
 	// t is a pointer to a struct, pointer to basic type or a slice.
-	// Allocate a "field" to store the pointer/slice itself; the
-	// pointer/slice will be stored here. We pass
-	// the address of this field to props.dec.
-	// This passes a zero field and a *t and lets props.dec
-	// interpret it as a *struct{ x t }.
+	// Allocate space to store the pointer/slice.
 	value := reflect.New(t).Elem()
 
+	var err error
 	for {
-		// Discard wire type and field number varint. It isn't needed.
-		if _, err := o.DecodeVarint(); err != nil {
-			return nil, err
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
 		}
+		b = b[n:]
+		wire := int(x) & 7
 
-		if err := props.dec(o, props, toStructPointer(value.Addr())); err != nil {
+		b, err = unmarshal(b, valToPointer(value.Addr()), wire)
+		if err != nil {
 			return nil, err
 		}
 
-		if o.index >= len(o.buf) {
+		if len(b) == 0 {
 			break
 		}
 	}
@@ -473,9 +445,9 @@ func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
 // GetExtensions returns a slice of the extensions present in pb that are also listed in es.
 // The returned slice has the same length as es; missing extensions will appear as nil elements.
 func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
-	epb, ok := extendable(pb)
-	if !ok {
-		return nil, errors.New("proto: not an extendable proto")
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
 	}
 	extensions = make([]interface{}, len(es))
 	for i, e := range es {
@@ -494,9 +466,9 @@ func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, e
 // For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing
 // just the Field field, which defines the extension's field number.
 func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
-	epb, ok := extendable(pb)
-	if !ok {
-		return nil, fmt.Errorf("proto: %T is not an extendable proto.Message", pb)
+	epb, err := extendable(pb)
+	if err != nil {
+		return nil, err
 	}
 	registeredExtensions := RegisteredExtensions(pb)
 
@@ -523,16 +495,16 @@ func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
 
 // SetExtension sets the specified extension of pb to the specified value.
 func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error {
-	epb, ok := extendable(pb)
-	if !ok {
-		return errors.New("proto: not an extendable proto")
+	epb, err := extendable(pb)
+	if err != nil {
+		return err
 	}
 	if err := checkExtensionTypes(epb, extension); err != nil {
 		return err
 	}
 	typ := reflect.TypeOf(extension.ExtensionType)
 	if typ != reflect.TypeOf(value) {
-		return errors.New("proto: bad extension value type")
+		return fmt.Errorf("proto: bad extension value type. got: %T, want: %T", value, extension.ExtensionType)
 	}
 	// nil extension values need to be caught early, because the
 	// encoder can't distinguish an ErrNil due to a nil extension
@@ -544,14 +516,14 @@ func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error
 	}
 
 	extmap := epb.extensionsWrite()
-	extmap[extension.Field] = Extension{desc: extension, value: value}
+	extmap[extension.Field] = Extension{desc: extension, value: extensionAsStorageType(value)}
 	return nil
 }
 
 // ClearAllExtensions clears all extensions from pb.
 func ClearAllExtensions(pb Message) {
-	epb, ok := extendable(pb)
-	if !ok {
+	epb, err := extendable(pb)
+	if err != nil {
 		return
 	}
 	m := epb.extensionsWrite()
@@ -585,3 +557,51 @@ func RegisterExtension(desc *ExtensionDesc) {
 func RegisteredExtensions(pb Message) map[int32]*ExtensionDesc {
 	return extensionMaps[reflect.TypeOf(pb).Elem()]
 }
+
+// extensionAsLegacyType converts an value in the storage type as the API type.
+// See Extension.value.
+func extensionAsLegacyType(v interface{}) interface{} {
+	switch rv := reflect.ValueOf(v); rv.Kind() {
+	case reflect.Bool, reflect.Int32, reflect.Int64, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64, reflect.String:
+		// Represent primitive types as a pointer to the value.
+		rv2 := reflect.New(rv.Type())
+		rv2.Elem().Set(rv)
+		v = rv2.Interface()
+	case reflect.Ptr:
+		// Represent slice types as the value itself.
+		switch rv.Type().Elem().Kind() {
+		case reflect.Slice:
+			if rv.IsNil() {
+				v = reflect.Zero(rv.Type().Elem()).Interface()
+			} else {
+				v = rv.Elem().Interface()
+			}
+		}
+	}
+	return v
+}
+
+// extensionAsStorageType converts an value in the API type as the storage type.
+// See Extension.value.
+func extensionAsStorageType(v interface{}) interface{} {
+	switch rv := reflect.ValueOf(v); rv.Kind() {
+	case reflect.Ptr:
+		// Represent slice types as the value itself.
+		switch rv.Type().Elem().Kind() {
+		case reflect.Bool, reflect.Int32, reflect.Int64, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64, reflect.String:
+			if rv.IsNil() {
+				v = reflect.Zero(rv.Type().Elem()).Interface()
+			} else {
+				v = rv.Elem().Interface()
+			}
+		}
+	case reflect.Slice:
+		// Represent slice types as a pointer to the value.
+		if rv.Type().Elem().Kind() != reflect.Uint8 {
+			rv2 := reflect.New(rv.Type())
+			rv2.Elem().Set(rv)
+			v = rv2.Interface()
+		}
+	}
+	return v
+}
diff --git a/vendor/github.com/golang/protobuf/proto/lib.go b/vendor/github.com/golang/protobuf/proto/lib.go
index 1c225504a0..fdd328bb7f 100644
--- a/vendor/github.com/golang/protobuf/proto/lib.go
+++ b/vendor/github.com/golang/protobuf/proto/lib.go
@@ -273,32 +273,73 @@ import (
 	"sync"
 )
 
-// Message is implemented by generated protocol buffer messages.
-type Message interface {
-	Reset()
-	String() string
-	ProtoMessage()
+// RequiredNotSetError is an error type returned by either Marshal or Unmarshal.
+// Marshal reports this when a required field is not initialized.
+// Unmarshal reports this when a required field is missing from the wire data.
+type RequiredNotSetError struct{ field string }
+
+func (e *RequiredNotSetError) Error() string {
+	if e.field == "" {
+		return fmt.Sprintf("proto: required field not set")
+	}
+	return fmt.Sprintf("proto: required field %q not set", e.field)
+}
+func (e *RequiredNotSetError) RequiredNotSet() bool {
+	return true
 }
 
-// Stats records allocation details about the protocol buffer encoders
-// and decoders.  Useful for tuning the library itself.
-type Stats struct {
-	Emalloc uint64 // mallocs in encode
-	Dmalloc uint64 // mallocs in decode
-	Encode  uint64 // number of encodes
-	Decode  uint64 // number of decodes
-	Chit    uint64 // number of cache hits
-	Cmiss   uint64 // number of cache misses
-	Size    uint64 // number of sizes
+type invalidUTF8Error struct{ field string }
+
+func (e *invalidUTF8Error) Error() string {
+	if e.field == "" {
+		return "proto: invalid UTF-8 detected"
+	}
+	return fmt.Sprintf("proto: field %q contains invalid UTF-8", e.field)
+}
+func (e *invalidUTF8Error) InvalidUTF8() bool {
+	return true
 }
 
-// Set to true to enable stats collection.
-const collectStats = false
+// errInvalidUTF8 is a sentinel error to identify fields with invalid UTF-8.
+// This error should not be exposed to the external API as such errors should
+// be recreated with the field information.
+var errInvalidUTF8 = &invalidUTF8Error{}
 
-var stats Stats
+// isNonFatal reports whether the error is either a RequiredNotSet error
+// or a InvalidUTF8 error.
+func isNonFatal(err error) bool {
+	if re, ok := err.(interface{ RequiredNotSet() bool }); ok && re.RequiredNotSet() {
+		return true
+	}
+	if re, ok := err.(interface{ InvalidUTF8() bool }); ok && re.InvalidUTF8() {
+		return true
+	}
+	return false
+}
 
-// GetStats returns a copy of the global Stats structure.
-func GetStats() Stats { return stats }
+type nonFatal struct{ E error }
+
+// Merge merges err into nf and reports whether it was successful.
+// Otherwise it returns false for any fatal non-nil errors.
+func (nf *nonFatal) Merge(err error) (ok bool) {
+	if err == nil {
+		return true // not an error
+	}
+	if !isNonFatal(err) {
+		return false // fatal error
+	}
+	if nf.E == nil {
+		nf.E = err // store first instance of non-fatal error
+	}
+	return true
+}
+
+// Message is implemented by generated protocol buffer messages.
+type Message interface {
+	Reset()
+	String() string
+	ProtoMessage()
+}
 
 // A Buffer is a buffer manager for marshaling and unmarshaling
 // protocol buffers.  It may be reused between invocations to
@@ -309,16 +350,7 @@ type Buffer struct {
 	buf   []byte // encode/decode byte stream
 	index int    // read point
 
-	// pools of basic types to amortize allocation.
-	bools   []bool
-	uint32s []uint32
-	uint64s []uint64
-
-	// extra pools, only used with pointer_reflect.go
-	int32s   []int32
-	int64s   []int64
-	float32s []float32
-	float64s []float64
+	deterministic bool
 }
 
 // NewBuffer allocates a new Buffer and initializes its internal data to
@@ -343,6 +375,30 @@ func (p *Buffer) SetBuf(s []byte) {
 // Bytes returns the contents of the Buffer.
 func (p *Buffer) Bytes() []byte { return p.buf }
 
+// SetDeterministic sets whether to use deterministic serialization.
+//
+// Deterministic serialization guarantees that for a given binary, equal
+// messages will always be serialized to the same bytes. This implies:
+//
+//   - Repeated serialization of a message will return the same bytes.
+//   - Different processes of the same binary (which may be executing on
+//     different machines) will serialize equal messages to the same bytes.
+//
+// Note that the deterministic serialization is NOT canonical across
+// languages. It is not guaranteed to remain stable over time. It is unstable
+// across different builds with schema changes due to unknown fields.
+// Users who need canonical serialization (e.g., persistent storage in a
+// canonical form, fingerprinting, etc.) should define their own
+// canonicalization specification and implement their own serializer rather
+// than relying on this API.
+//
+// If deterministic serialization is requested, map entries will be sorted
+// by keys in lexographical order. This is an implementation detail and
+// subject to change.
+func (p *Buffer) SetDeterministic(deterministic bool) {
+	p.deterministic = deterministic
+}
+
 /*
  * Helper routines for simplifying the creation of optional fields of basic type.
  */
@@ -831,22 +887,12 @@ func fieldDefault(ft reflect.Type, prop *Properties) (sf *scalarField, nestedMes
 	return sf, false, nil
 }
 
+// mapKeys returns a sort.Interface to be used for sorting the map keys.
 // Map fields may have key types of non-float scalars, strings and enums.
-// The easiest way to sort them in some deterministic order is to use fmt.
-// If this turns out to be inefficient we can always consider other options,
-// such as doing a Schwartzian transform.
-
 func mapKeys(vs []reflect.Value) sort.Interface {
-	s := mapKeySorter{
-		vs: vs,
-		// default Less function: textual comparison
-		less: func(a, b reflect.Value) bool {
-			return fmt.Sprint(a.Interface()) < fmt.Sprint(b.Interface())
-		},
-	}
+	s := mapKeySorter{vs: vs}
 
-	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps;
-	// numeric keys are sorted numerically.
+	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps.
 	if len(vs) == 0 {
 		return s
 	}
@@ -855,6 +901,12 @@ func mapKeys(vs []reflect.Value) sort.Interface {
 		s.less = func(a, b reflect.Value) bool { return a.Int() < b.Int() }
 	case reflect.Uint32, reflect.Uint64:
 		s.less = func(a, b reflect.Value) bool { return a.Uint() < b.Uint() }
+	case reflect.Bool:
+		s.less = func(a, b reflect.Value) bool { return !a.Bool() && b.Bool() } // false < true
+	case reflect.String:
+		s.less = func(a, b reflect.Value) bool { return a.String() < b.String() }
+	default:
+		panic(fmt.Sprintf("unsupported map key type: %v", vs[0].Kind()))
 	}
 
 	return s
@@ -888,10 +940,26 @@ func isProto3Zero(v reflect.Value) bool {
 	return false
 }
 
-// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
-// to assert that that code is compatible with this version of the proto package.
-const ProtoPackageIsVersion2 = true
+const (
+	// ProtoPackageIsVersion3 is referenced from generated protocol buffer files
+	// to assert that that code is compatible with this version of the proto package.
+	ProtoPackageIsVersion3 = true
+
+	// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
+	// to assert that that code is compatible with this version of the proto package.
+	ProtoPackageIsVersion2 = true
 
-// ProtoPackageIsVersion1 is referenced from generated protocol buffer files
-// to assert that that code is compatible with this version of the proto package.
-const ProtoPackageIsVersion1 = true
+	// ProtoPackageIsVersion1 is referenced from generated protocol buffer files
+	// to assert that that code is compatible with this version of the proto package.
+	ProtoPackageIsVersion1 = true
+)
+
+// InternalMessageInfo is a type used internally by generated .pb.go files.
+// This type is not intended to be used by non-generated code.
+// This type is not subject to any compatibility guarantee.
+type InternalMessageInfo struct {
+	marshal   *marshalInfo
+	unmarshal *unmarshalInfo
+	merge     *mergeInfo
+	discard   *discardInfo
+}
diff --git a/vendor/github.com/golang/protobuf/proto/message_set.go b/vendor/github.com/golang/protobuf/proto/message_set.go
index fd982decd6..f48a756761 100644
--- a/vendor/github.com/golang/protobuf/proto/message_set.go
+++ b/vendor/github.com/golang/protobuf/proto/message_set.go
@@ -36,12 +36,7 @@ package proto
  */
 
 import (
-	"bytes"
-	"encoding/json"
 	"errors"
-	"fmt"
-	"reflect"
-	"sort"
 )
 
 // errNoMessageTypeID occurs when a protocol buffer does not have a message type ID.
@@ -94,10 +89,7 @@ func (ms *messageSet) find(pb Message) *_MessageSet_Item {
 }
 
 func (ms *messageSet) Has(pb Message) bool {
-	if ms.find(pb) != nil {
-		return true
-	}
-	return false
+	return ms.find(pb) != nil
 }
 
 func (ms *messageSet) Unmarshal(pb Message) error {
@@ -147,50 +139,9 @@ func skipVarint(buf []byte) []byte {
 	return buf[i+1:]
 }
 
-// MarshalMessageSet encodes the extension map represented by m in the message set wire format.
-// It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
-func MarshalMessageSet(exts interface{}) ([]byte, error) {
-	var m map[int32]Extension
-	switch exts := exts.(type) {
-	case *XXX_InternalExtensions:
-		if err := encodeExtensions(exts); err != nil {
-			return nil, err
-		}
-		m, _ = exts.extensionsRead()
-	case map[int32]Extension:
-		if err := encodeExtensionsMap(exts); err != nil {
-			return nil, err
-		}
-		m = exts
-	default:
-		return nil, errors.New("proto: not an extension map")
-	}
-
-	// Sort extension IDs to provide a deterministic encoding.
-	// See also enc_map in encode.go.
-	ids := make([]int, 0, len(m))
-	for id := range m {
-		ids = append(ids, int(id))
-	}
-	sort.Ints(ids)
-
-	ms := &messageSet{Item: make([]*_MessageSet_Item, 0, len(m))}
-	for _, id := range ids {
-		e := m[int32(id)]
-		// Remove the wire type and field number varint, as well as the length varint.
-		msg := skipVarint(skipVarint(e.enc))
-
-		ms.Item = append(ms.Item, &_MessageSet_Item{
-			TypeId:  Int32(int32(id)),
-			Message: msg,
-		})
-	}
-	return Marshal(ms)
-}
-
-// UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
-// It is called by generated Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
-func UnmarshalMessageSet(buf []byte, exts interface{}) error {
+// unmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
+// It is called by Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
+func unmarshalMessageSet(buf []byte, exts interface{}) error {
 	var m map[int32]Extension
 	switch exts := exts.(type) {
 	case *XXX_InternalExtensions:
@@ -228,84 +179,3 @@ func UnmarshalMessageSet(buf []byte, exts interface{}) error {
 	}
 	return nil
 }
-
-// MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
-// It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
-func MarshalMessageSetJSON(exts interface{}) ([]byte, error) {
-	var m map[int32]Extension
-	switch exts := exts.(type) {
-	case *XXX_InternalExtensions:
-		m, _ = exts.extensionsRead()
-	case map[int32]Extension:
-		m = exts
-	default:
-		return nil, errors.New("proto: not an extension map")
-	}
-	var b bytes.Buffer
-	b.WriteByte('{')
-
-	// Process the map in key order for deterministic output.
-	ids := make([]int32, 0, len(m))
-	for id := range m {
-		ids = append(ids, id)
-	}
-	sort.Sort(int32Slice(ids)) // int32Slice defined in text.go
-
-	for i, id := range ids {
-		ext := m[id]
-		if i > 0 {
-			b.WriteByte(',')
-		}
-
-		msd, ok := messageSetMap[id]
-		if !ok {
-			// Unknown type; we can't render it, so skip it.
-			continue
-		}
-		fmt.Fprintf(&b, `"[%s]":`, msd.name)
-
-		x := ext.value
-		if x == nil {
-			x = reflect.New(msd.t.Elem()).Interface()
-			if err := Unmarshal(ext.enc, x.(Message)); err != nil {
-				return nil, err
-			}
-		}
-		d, err := json.Marshal(x)
-		if err != nil {
-			return nil, err
-		}
-		b.Write(d)
-	}
-	b.WriteByte('}')
-	return b.Bytes(), nil
-}
-
-// UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
-// It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
-func UnmarshalMessageSetJSON(buf []byte, exts interface{}) error {
-	// Common-case fast path.
-	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
-		return nil
-	}
-
-	// This is fairly tricky, and it's not clear that it is needed.
-	return errors.New("TODO: UnmarshalMessageSetJSON not yet implemented")
-}
-
-// A global registry of types that can be used in a MessageSet.
-
-var messageSetMap = make(map[int32]messageSetDesc)
-
-type messageSetDesc struct {
-	t    reflect.Type // pointer to struct
-	name string
-}
-
-// RegisterMessageSetType is called from the generated code.
-func RegisterMessageSetType(m Message, fieldNum int32, name string) {
-	messageSetMap[fieldNum] = messageSetDesc{
-		t:    reflect.TypeOf(m),
-		name: name,
-	}
-}
diff --git a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
index fb512e2e16..94fa9194a8 100644
--- a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
+++ b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
@@ -29,7 +29,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// +build appengine js
+// +build purego appengine js
 
 // This file contains an implementation of proto field accesses using package reflect.
 // It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
@@ -38,32 +38,13 @@
 package proto
 
 import (
-	"math"
 	"reflect"
+	"sync"
 )
 
-// A structPointer is a pointer to a struct.
-type structPointer struct {
-	v reflect.Value
-}
-
-// toStructPointer returns a structPointer equivalent to the given reflect value.
-// The reflect value must itself be a pointer to a struct.
-func toStructPointer(v reflect.Value) structPointer {
-	return structPointer{v}
-}
-
-// IsNil reports whether p is nil.
-func structPointer_IsNil(p structPointer) bool {
-	return p.v.IsNil()
-}
+const unsafeAllowed = false
 
-// Interface returns the struct pointer as an interface value.
-func structPointer_Interface(p structPointer, _ reflect.Type) interface{} {
-	return p.v.Interface()
-}
-
-// A field identifies a field in a struct, accessible from a structPointer.
+// A field identifies a field in a struct, accessible from a pointer.
 // In this implementation, a field is identified by the sequence of field indices
 // passed to reflect's FieldByIndex.
 type field []int
@@ -76,409 +57,304 @@ func toField(f *reflect.StructField) field {
 // invalidField is an invalid field identifier.
 var invalidField = field(nil)
 
+// zeroField is a noop when calling pointer.offset.
+var zeroField = field([]int{})
+
 // IsValid reports whether the field identifier is valid.
 func (f field) IsValid() bool { return f != nil }
 
-// field returns the given field in the struct as a reflect value.
-func structPointer_field(p structPointer, f field) reflect.Value {
-	// Special case: an extension map entry with a value of type T
-	// passes a *T to the struct-handling code with a zero field,
-	// expecting that it will be treated as equivalent to *struct{ X T },
-	// which has the same memory layout. We have to handle that case
-	// specially, because reflect will panic if we call FieldByIndex on a
-	// non-struct.
-	if f == nil {
-		return p.v.Elem()
-	}
-
-	return p.v.Elem().FieldByIndex(f)
+// The pointer type is for the table-driven decoder.
+// The implementation here uses a reflect.Value of pointer type to
+// create a generic pointer. In pointer_unsafe.go we use unsafe
+// instead of reflect to implement the same (but faster) interface.
+type pointer struct {
+	v reflect.Value
 }
 
-// ifield returns the given field in the struct as an interface value.
-func structPointer_ifield(p structPointer, f field) interface{} {
-	return structPointer_field(p, f).Addr().Interface()
+// toPointer converts an interface of pointer type to a pointer
+// that points to the same target.
+func toPointer(i *Message) pointer {
+	return pointer{v: reflect.ValueOf(*i)}
 }
 
-// Bytes returns the address of a []byte field in the struct.
-func structPointer_Bytes(p structPointer, f field) *[]byte {
-	return structPointer_ifield(p, f).(*[]byte)
+// toAddrPointer converts an interface to a pointer that points to
+// the interface data.
+func toAddrPointer(i *interface{}, isptr, deref bool) pointer {
+	v := reflect.ValueOf(*i)
+	u := reflect.New(v.Type())
+	u.Elem().Set(v)
+	if deref {
+		u = u.Elem()
+	}
+	return pointer{v: u}
 }
 
-// BytesSlice returns the address of a [][]byte field in the struct.
-func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
-	return structPointer_ifield(p, f).(*[][]byte)
+// valToPointer converts v to a pointer.  v must be of pointer type.
+func valToPointer(v reflect.Value) pointer {
+	return pointer{v: v}
 }
 
-// Bool returns the address of a *bool field in the struct.
-func structPointer_Bool(p structPointer, f field) **bool {
-	return structPointer_ifield(p, f).(**bool)
+// offset converts from a pointer to a structure to a pointer to
+// one of its fields.
+func (p pointer) offset(f field) pointer {
+	return pointer{v: p.v.Elem().FieldByIndex(f).Addr()}
 }
 
-// BoolVal returns the address of a bool field in the struct.
-func structPointer_BoolVal(p structPointer, f field) *bool {
-	return structPointer_ifield(p, f).(*bool)
+func (p pointer) isNil() bool {
+	return p.v.IsNil()
 }
 
-// BoolSlice returns the address of a []bool field in the struct.
-func structPointer_BoolSlice(p structPointer, f field) *[]bool {
-	return structPointer_ifield(p, f).(*[]bool)
+// grow updates the slice s in place to make it one element longer.
+// s must be addressable.
+// Returns the (addressable) new element.
+func grow(s reflect.Value) reflect.Value {
+	n, m := s.Len(), s.Cap()
+	if n < m {
+		s.SetLen(n + 1)
+	} else {
+		s.Set(reflect.Append(s, reflect.Zero(s.Type().Elem())))
+	}
+	return s.Index(n)
 }
 
-// String returns the address of a *string field in the struct.
-func structPointer_String(p structPointer, f field) **string {
-	return structPointer_ifield(p, f).(**string)
+func (p pointer) toInt64() *int64 {
+	return p.v.Interface().(*int64)
 }
-
-// StringVal returns the address of a string field in the struct.
-func structPointer_StringVal(p structPointer, f field) *string {
-	return structPointer_ifield(p, f).(*string)
+func (p pointer) toInt64Ptr() **int64 {
+	return p.v.Interface().(**int64)
 }
-
-// StringSlice returns the address of a []string field in the struct.
-func structPointer_StringSlice(p structPointer, f field) *[]string {
-	return structPointer_ifield(p, f).(*[]string)
+func (p pointer) toInt64Slice() *[]int64 {
+	return p.v.Interface().(*[]int64)
 }
 
-// Extensions returns the address of an extension map field in the struct.
-func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
-	return structPointer_ifield(p, f).(*XXX_InternalExtensions)
-}
+var int32ptr = reflect.TypeOf((*int32)(nil))
 
-// ExtMap returns the address of an extension map field in the struct.
-func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
-	return structPointer_ifield(p, f).(*map[int32]Extension)
+func (p pointer) toInt32() *int32 {
+	return p.v.Convert(int32ptr).Interface().(*int32)
 }
 
-// NewAt returns the reflect.Value for a pointer to a field in the struct.
-func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
-	return structPointer_field(p, f).Addr()
+// The toInt32Ptr/Slice methods don't work because of enums.
+// Instead, we must use set/get methods for the int32ptr/slice case.
+/*
+	func (p pointer) toInt32Ptr() **int32 {
+		return p.v.Interface().(**int32)
 }
-
-// SetStructPointer writes a *struct field in the struct.
-func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
-	structPointer_field(p, f).Set(q.v)
+	func (p pointer) toInt32Slice() *[]int32 {
+		return p.v.Interface().(*[]int32)
 }
-
-// GetStructPointer reads a *struct field in the struct.
-func structPointer_GetStructPointer(p structPointer, f field) structPointer {
-	return structPointer{structPointer_field(p, f)}
+*/
+func (p pointer) getInt32Ptr() *int32 {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		return p.v.Elem().Interface().(*int32)
+	}
+	// an enum
+	return p.v.Elem().Convert(int32PtrType).Interface().(*int32)
+}
+func (p pointer) setInt32Ptr(v int32) {
+	// Allocate value in a *int32. Possibly convert that to a *enum.
+	// Then assign it to a **int32 or **enum.
+	// Note: we can convert *int32 to *enum, but we can't convert
+	// **int32 to **enum!
+	p.v.Elem().Set(reflect.ValueOf(&v).Convert(p.v.Type().Elem()))
+}
+
+// getInt32Slice copies []int32 from p as a new slice.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) getInt32Slice() []int32 {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		return p.v.Elem().Interface().([]int32)
+	}
+	// an enum
+	// Allocate a []int32, then assign []enum's values into it.
+	// Note: we can't convert []enum to []int32.
+	slice := p.v.Elem()
+	s := make([]int32, slice.Len())
+	for i := 0; i < slice.Len(); i++ {
+		s[i] = int32(slice.Index(i).Int())
+	}
+	return s
 }
 
-// StructPointerSlice the address of a []*struct field in the struct.
-func structPointer_StructPointerSlice(p structPointer, f field) structPointerSlice {
-	return structPointerSlice{structPointer_field(p, f)}
+// setInt32Slice copies []int32 into p as a new slice.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) setInt32Slice(v []int32) {
+	if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
+		// raw int32 type
+		p.v.Elem().Set(reflect.ValueOf(v))
+		return
+	}
+	// an enum
+	// Allocate a []enum, then assign []int32's values into it.
+	// Note: we can't convert []enum to []int32.
+	slice := reflect.MakeSlice(p.v.Type().Elem(), len(v), cap(v))
+	for i, x := range v {
+		slice.Index(i).SetInt(int64(x))
+	}
+	p.v.Elem().Set(slice)
 }
-
-// A structPointerSlice represents the address of a slice of pointers to structs
-// (themselves messages or groups). That is, v.Type() is *[]*struct{...}.
-type structPointerSlice struct {
-	v reflect.Value
+func (p pointer) appendInt32Slice(v int32) {
+	grow(p.v.Elem()).SetInt(int64(v))
 }
 
-func (p structPointerSlice) Len() int                  { return p.v.Len() }
-func (p structPointerSlice) Index(i int) structPointer { return structPointer{p.v.Index(i)} }
-func (p structPointerSlice) Append(q structPointer) {
-	p.v.Set(reflect.Append(p.v, q.v))
+func (p pointer) toUint64() *uint64 {
+	return p.v.Interface().(*uint64)
 }
-
-var (
-	int32Type   = reflect.TypeOf(int32(0))
-	uint32Type  = reflect.TypeOf(uint32(0))
-	float32Type = reflect.TypeOf(float32(0))
-	int64Type   = reflect.TypeOf(int64(0))
-	uint64Type  = reflect.TypeOf(uint64(0))
-	float64Type = reflect.TypeOf(float64(0))
-)
-
-// A word32 represents a field of type *int32, *uint32, *float32, or *enum.
-// That is, v.Type() is *int32, *uint32, *float32, or *enum and v is assignable.
-type word32 struct {
-	v reflect.Value
+func (p pointer) toUint64Ptr() **uint64 {
+	return p.v.Interface().(**uint64)
 }
-
-// IsNil reports whether p is nil.
-func word32_IsNil(p word32) bool {
-	return p.v.IsNil()
+func (p pointer) toUint64Slice() *[]uint64 {
+	return p.v.Interface().(*[]uint64)
 }
-
-// Set sets p to point at a newly allocated word with bits set to x.
-func word32_Set(p word32, o *Buffer, x uint32) {
-	t := p.v.Type().Elem()
-	switch t {
-	case int32Type:
-		if len(o.int32s) == 0 {
-			o.int32s = make([]int32, uint32PoolSize)
-		}
-		o.int32s[0] = int32(x)
-		p.v.Set(reflect.ValueOf(&o.int32s[0]))
-		o.int32s = o.int32s[1:]
-		return
-	case uint32Type:
-		if len(o.uint32s) == 0 {
-			o.uint32s = make([]uint32, uint32PoolSize)
-		}
-		o.uint32s[0] = x
-		p.v.Set(reflect.ValueOf(&o.uint32s[0]))
-		o.uint32s = o.uint32s[1:]
-		return
-	case float32Type:
-		if len(o.float32s) == 0 {
-			o.float32s = make([]float32, uint32PoolSize)
-		}
-		o.float32s[0] = math.Float32frombits(x)
-		p.v.Set(reflect.ValueOf(&o.float32s[0]))
-		o.float32s = o.float32s[1:]
-		return
-	}
-
-	// must be enum
-	p.v.Set(reflect.New(t))
-	p.v.Elem().SetInt(int64(int32(x)))
+func (p pointer) toUint32() *uint32 {
+	return p.v.Interface().(*uint32)
 }
-
-// Get gets the bits pointed at by p, as a uint32.
-func word32_Get(p word32) uint32 {
-	elem := p.v.Elem()
-	switch elem.Kind() {
-	case reflect.Int32:
-		return uint32(elem.Int())
-	case reflect.Uint32:
-		return uint32(elem.Uint())
-	case reflect.Float32:
-		return math.Float32bits(float32(elem.Float()))
-	}
-	panic("unreachable")
+func (p pointer) toUint32Ptr() **uint32 {
+	return p.v.Interface().(**uint32)
 }
-
-// Word32 returns a reference to a *int32, *uint32, *float32, or *enum field in the struct.
-func structPointer_Word32(p structPointer, f field) word32 {
-	return word32{structPointer_field(p, f)}
+func (p pointer) toUint32Slice() *[]uint32 {
+	return p.v.Interface().(*[]uint32)
 }
-
-// A word32Val represents a field of type int32, uint32, float32, or enum.
-// That is, v.Type() is int32, uint32, float32, or enum and v is assignable.
-type word32Val struct {
-	v reflect.Value
+func (p pointer) toBool() *bool {
+	return p.v.Interface().(*bool)
 }
-
-// Set sets *p to x.
-func word32Val_Set(p word32Val, x uint32) {
-	switch p.v.Type() {
-	case int32Type:
-		p.v.SetInt(int64(x))
-		return
-	case uint32Type:
-		p.v.SetUint(uint64(x))
-		return
-	case float32Type:
-		p.v.SetFloat(float64(math.Float32frombits(x)))
-		return
-	}
-
-	// must be enum
-	p.v.SetInt(int64(int32(x)))
+func (p pointer) toBoolPtr() **bool {
+	return p.v.Interface().(**bool)
 }
-
-// Get gets the bits pointed at by p, as a uint32.
-func word32Val_Get(p word32Val) uint32 {
-	elem := p.v
-	switch elem.Kind() {
-	case reflect.Int32:
-		return uint32(elem.Int())
-	case reflect.Uint32:
-		return uint32(elem.Uint())
-	case reflect.Float32:
-		return math.Float32bits(float32(elem.Float()))
-	}
-	panic("unreachable")
+func (p pointer) toBoolSlice() *[]bool {
+	return p.v.Interface().(*[]bool)
 }
-
-// Word32Val returns a reference to a int32, uint32, float32, or enum field in the struct.
-func structPointer_Word32Val(p structPointer, f field) word32Val {
-	return word32Val{structPointer_field(p, f)}
+func (p pointer) toFloat64() *float64 {
+	return p.v.Interface().(*float64)
 }
-
-// A word32Slice is a slice of 32-bit values.
-// That is, v.Type() is []int32, []uint32, []float32, or []enum.
-type word32Slice struct {
-	v reflect.Value
+func (p pointer) toFloat64Ptr() **float64 {
+	return p.v.Interface().(**float64)
 }
-
-func (p word32Slice) Append(x uint32) {
-	n, m := p.v.Len(), p.v.Cap()
-	if n < m {
-		p.v.SetLen(n + 1)
-	} else {
-		t := p.v.Type().Elem()
-		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
-	}
-	elem := p.v.Index(n)
-	switch elem.Kind() {
-	case reflect.Int32:
-		elem.SetInt(int64(int32(x)))
-	case reflect.Uint32:
-		elem.SetUint(uint64(x))
-	case reflect.Float32:
-		elem.SetFloat(float64(math.Float32frombits(x)))
-	}
+func (p pointer) toFloat64Slice() *[]float64 {
+	return p.v.Interface().(*[]float64)
 }
-
-func (p word32Slice) Len() int {
-	return p.v.Len()
+func (p pointer) toFloat32() *float32 {
+	return p.v.Interface().(*float32)
 }
-
-func (p word32Slice) Index(i int) uint32 {
-	elem := p.v.Index(i)
-	switch elem.Kind() {
-	case reflect.Int32:
-		return uint32(elem.Int())
-	case reflect.Uint32:
-		return uint32(elem.Uint())
-	case reflect.Float32:
-		return math.Float32bits(float32(elem.Float()))
-	}
-	panic("unreachable")
+func (p pointer) toFloat32Ptr() **float32 {
+	return p.v.Interface().(**float32)
 }
-
-// Word32Slice returns a reference to a []int32, []uint32, []float32, or []enum field in the struct.
-func structPointer_Word32Slice(p structPointer, f field) word32Slice {
-	return word32Slice{structPointer_field(p, f)}
+func (p pointer) toFloat32Slice() *[]float32 {
+	return p.v.Interface().(*[]float32)
 }
-
-// word64 is like word32 but for 64-bit values.
-type word64 struct {
-	v reflect.Value
+func (p pointer) toString() *string {
+	return p.v.Interface().(*string)
 }
-
-func word64_Set(p word64, o *Buffer, x uint64) {
-	t := p.v.Type().Elem()
-	switch t {
-	case int64Type:
-		if len(o.int64s) == 0 {
-			o.int64s = make([]int64, uint64PoolSize)
-		}
-		o.int64s[0] = int64(x)
-		p.v.Set(reflect.ValueOf(&o.int64s[0]))
-		o.int64s = o.int64s[1:]
-		return
-	case uint64Type:
-		if len(o.uint64s) == 0 {
-			o.uint64s = make([]uint64, uint64PoolSize)
-		}
-		o.uint64s[0] = x
-		p.v.Set(reflect.ValueOf(&o.uint64s[0]))
-		o.uint64s = o.uint64s[1:]
-		return
-	case float64Type:
-		if len(o.float64s) == 0 {
-			o.float64s = make([]float64, uint64PoolSize)
-		}
-		o.float64s[0] = math.Float64frombits(x)
-		p.v.Set(reflect.ValueOf(&o.float64s[0]))
-		o.float64s = o.float64s[1:]
-		return
-	}
-	panic("unreachable")
+func (p pointer) toStringPtr() **string {
+	return p.v.Interface().(**string)
 }
-
-func word64_IsNil(p word64) bool {
-	return p.v.IsNil()
+func (p pointer) toStringSlice() *[]string {
+	return p.v.Interface().(*[]string)
 }
-
-func word64_Get(p word64) uint64 {
-	elem := p.v.Elem()
-	switch elem.Kind() {
-	case reflect.Int64:
-		return uint64(elem.Int())
-	case reflect.Uint64:
-		return elem.Uint()
-	case reflect.Float64:
-		return math.Float64bits(elem.Float())
-	}
-	panic("unreachable")
+func (p pointer) toBytes() *[]byte {
+	return p.v.Interface().(*[]byte)
 }
-
-func structPointer_Word64(p structPointer, f field) word64 {
-	return word64{structPointer_field(p, f)}
+func (p pointer) toBytesSlice() *[][]byte {
+	return p.v.Interface().(*[][]byte)
+}
+func (p pointer) toExtensions() *XXX_InternalExtensions {
+	return p.v.Interface().(*XXX_InternalExtensions)
+}
+func (p pointer) toOldExtensions() *map[int32]Extension {
+	return p.v.Interface().(*map[int32]Extension)
+}
+func (p pointer) getPointer() pointer {
+	return pointer{v: p.v.Elem()}
+}
+func (p pointer) setPointer(q pointer) {
+	p.v.Elem().Set(q.v)
+}
+func (p pointer) appendPointer(q pointer) {
+	grow(p.v.Elem()).Set(q.v)
 }
 
-// word64Val is like word32Val but for 64-bit values.
-type word64Val struct {
-	v reflect.Value
+// getPointerSlice copies []*T from p as a new []pointer.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) getPointerSlice() []pointer {
+	if p.v.IsNil() {
+		return nil
+	}
+	n := p.v.Elem().Len()
+	s := make([]pointer, n)
+	for i := 0; i < n; i++ {
+		s[i] = pointer{v: p.v.Elem().Index(i)}
+	}
+	return s
 }
 
-func word64Val_Set(p word64Val, o *Buffer, x uint64) {
-	switch p.v.Type() {
-	case int64Type:
-		p.v.SetInt(int64(x))
-		return
-	case uint64Type:
-		p.v.SetUint(x)
-		return
-	case float64Type:
-		p.v.SetFloat(math.Float64frombits(x))
+// setPointerSlice copies []pointer into p as a new []*T.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) setPointerSlice(v []pointer) {
+	if v == nil {
+		p.v.Elem().Set(reflect.New(p.v.Elem().Type()).Elem())
 		return
 	}
-	panic("unreachable")
+	s := reflect.MakeSlice(p.v.Elem().Type(), 0, len(v))
+	for _, p := range v {
+		s = reflect.Append(s, p.v)
+	}
+	p.v.Elem().Set(s)
 }
 
-func word64Val_Get(p word64Val) uint64 {
-	elem := p.v
-	switch elem.Kind() {
-	case reflect.Int64:
-		return uint64(elem.Int())
-	case reflect.Uint64:
-		return elem.Uint()
-	case reflect.Float64:
-		return math.Float64bits(elem.Float())
+// getInterfacePointer returns a pointer that points to the
+// interface data of the interface pointed by p.
+func (p pointer) getInterfacePointer() pointer {
+	if p.v.Elem().IsNil() {
+		return pointer{v: p.v.Elem()}
 	}
-	panic("unreachable")
+	return pointer{v: p.v.Elem().Elem().Elem().Field(0).Addr()} // *interface -> interface -> *struct -> struct
 }
 
-func structPointer_Word64Val(p structPointer, f field) word64Val {
-	return word64Val{structPointer_field(p, f)}
+func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
+	// TODO: check that p.v.Type().Elem() == t?
+	return p.v
 }
 
-type word64Slice struct {
-	v reflect.Value
+func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
 }
-
-func (p word64Slice) Append(x uint64) {
-	n, m := p.v.Len(), p.v.Cap()
-	if n < m {
-		p.v.SetLen(n + 1)
-	} else {
-		t := p.v.Type().Elem()
-		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
-	}
-	elem := p.v.Index(n)
-	switch elem.Kind() {
-	case reflect.Int64:
-		elem.SetInt(int64(int64(x)))
-	case reflect.Uint64:
-		elem.SetUint(uint64(x))
-	case reflect.Float64:
-		elem.SetFloat(float64(math.Float64frombits(x)))
-	}
+func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
 }
-
-func (p word64Slice) Len() int {
-	return p.v.Len()
+func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
 }
-
-func (p word64Slice) Index(i int) uint64 {
-	elem := p.v.Index(i)
-	switch elem.Kind() {
-	case reflect.Int64:
-		return uint64(elem.Int())
-	case reflect.Uint64:
-		return uint64(elem.Uint())
-	case reflect.Float64:
-		return math.Float64bits(float64(elem.Float()))
-	}
-	panic("unreachable")
+func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
 }
-
-func structPointer_Word64Slice(p structPointer, f field) word64Slice {
-	return word64Slice{structPointer_field(p, f)}
+func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
 }
+func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	return *p
+}
+func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
+	atomicLock.Lock()
+	defer atomicLock.Unlock()
+	*p = v
+}
+
+var atomicLock sync.Mutex
diff --git a/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go b/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
index 6b5567d47c..dbfffe071b 100644
--- a/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
+++ b/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
@@ -29,7 +29,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// +build !appengine,!js
+// +build !purego,!appengine,!js
 
 // This file contains the implementation of the proto field accesses using package unsafe.
 
@@ -37,38 +37,13 @@ package proto
 
 import (
 	"reflect"
+	"sync/atomic"
 	"unsafe"
 )
 
-// NOTE: These type_Foo functions would more idiomatically be methods,
-// but Go does not allow methods on pointer types, and we must preserve
-// some pointer type for the garbage collector. We use these
-// funcs with clunky names as our poor approximation to methods.
-//
-// An alternative would be
-//	type structPointer struct { p unsafe.Pointer }
-// but that does not registerize as well.
-
-// A structPointer is a pointer to a struct.
-type structPointer unsafe.Pointer
-
-// toStructPointer returns a structPointer equivalent to the given reflect value.
-func toStructPointer(v reflect.Value) structPointer {
-	return structPointer(unsafe.Pointer(v.Pointer()))
-}
-
-// IsNil reports whether p is nil.
-func structPointer_IsNil(p structPointer) bool {
-	return p == nil
-}
-
-// Interface returns the struct pointer, assumed to have element type t,
-// as an interface value.
-func structPointer_Interface(p structPointer, t reflect.Type) interface{} {
-	return reflect.NewAt(t, unsafe.Pointer(p)).Interface()
-}
+const unsafeAllowed = true
 
-// A field identifies a field in a struct, accessible from a structPointer.
+// A field identifies a field in a struct, accessible from a pointer.
 // In this implementation, a field is identified by its byte offset from the start of the struct.
 type field uintptr
 
@@ -80,191 +55,259 @@ func toField(f *reflect.StructField) field {
 // invalidField is an invalid field identifier.
 const invalidField = ^field(0)
 
+// zeroField is a noop when calling pointer.offset.
+const zeroField = field(0)
+
 // IsValid reports whether the field identifier is valid.
 func (f field) IsValid() bool {
-	return f != ^field(0)
+	return f != invalidField
+}
+
+// The pointer type below is for the new table-driven encoder/decoder.
+// The implementation here uses unsafe.Pointer to create a generic pointer.
+// In pointer_reflect.go we use reflect instead of unsafe to implement
+// the same (but slower) interface.
+type pointer struct {
+	p unsafe.Pointer
+}
+
+// size of pointer
+var ptrSize = unsafe.Sizeof(uintptr(0))
+
+// toPointer converts an interface of pointer type to a pointer
+// that points to the same target.
+func toPointer(i *Message) pointer {
+	// Super-tricky - read pointer out of data word of interface value.
+	// Saves ~25ns over the equivalent:
+	// return valToPointer(reflect.ValueOf(*i))
+	return pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
+}
+
+// toAddrPointer converts an interface to a pointer that points to
+// the interface data.
+func toAddrPointer(i *interface{}, isptr, deref bool) (p pointer) {
+	// Super-tricky - read or get the address of data word of interface value.
+	if isptr {
+		// The interface is of pointer type, thus it is a direct interface.
+		// The data word is the pointer data itself. We take its address.
+		p = pointer{p: unsafe.Pointer(uintptr(unsafe.Pointer(i)) + ptrSize)}
+	} else {
+		// The interface is not of pointer type. The data word is the pointer
+		// to the data.
+		p = pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
+	}
+	if deref {
+		p.p = *(*unsafe.Pointer)(p.p)
+	}
+	return p
 }
 
-// Bytes returns the address of a []byte field in the struct.
-func structPointer_Bytes(p structPointer, f field) *[]byte {
-	return (*[]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+// valToPointer converts v to a pointer. v must be of pointer type.
+func valToPointer(v reflect.Value) pointer {
+	return pointer{p: unsafe.Pointer(v.Pointer())}
 }
 
-// BytesSlice returns the address of a [][]byte field in the struct.
-func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
-	return (*[][]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+// offset converts from a pointer to a structure to a pointer to
+// one of its fields.
+func (p pointer) offset(f field) pointer {
+	// For safety, we should panic if !f.IsValid, however calling panic causes
+	// this to no longer be inlineable, which is a serious performance cost.
+	/*
+		if !f.IsValid() {
+			panic("invalid field")
+		}
+	*/
+	return pointer{p: unsafe.Pointer(uintptr(p.p) + uintptr(f))}
 }
 
-// Bool returns the address of a *bool field in the struct.
-func structPointer_Bool(p structPointer, f field) **bool {
-	return (**bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) isNil() bool {
+	return p.p == nil
 }
 
-// BoolVal returns the address of a bool field in the struct.
-func structPointer_BoolVal(p structPointer, f field) *bool {
-	return (*bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toInt64() *int64 {
+	return (*int64)(p.p)
 }
-
-// BoolSlice returns the address of a []bool field in the struct.
-func structPointer_BoolSlice(p structPointer, f field) *[]bool {
-	return (*[]bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toInt64Ptr() **int64 {
+	return (**int64)(p.p)
 }
-
-// String returns the address of a *string field in the struct.
-func structPointer_String(p structPointer, f field) **string {
-	return (**string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toInt64Slice() *[]int64 {
+	return (*[]int64)(p.p)
 }
-
-// StringVal returns the address of a string field in the struct.
-func structPointer_StringVal(p structPointer, f field) *string {
-	return (*string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toInt32() *int32 {
+	return (*int32)(p.p)
 }
 
-// StringSlice returns the address of a []string field in the struct.
-func structPointer_StringSlice(p structPointer, f field) *[]string {
-	return (*[]string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+// See pointer_reflect.go for why toInt32Ptr/Slice doesn't exist.
+/*
+	func (p pointer) toInt32Ptr() **int32 {
+		return (**int32)(p.p)
+	}
+	func (p pointer) toInt32Slice() *[]int32 {
+		return (*[]int32)(p.p)
+	}
+*/
+func (p pointer) getInt32Ptr() *int32 {
+	return *(**int32)(p.p)
 }
-
-// ExtMap returns the address of an extension map field in the struct.
-func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
-	return (*XXX_InternalExtensions)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) setInt32Ptr(v int32) {
+	*(**int32)(p.p) = &v
 }
 
-func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
-	return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+// getInt32Slice loads a []int32 from p.
+// The value returned is aliased with the original slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) getInt32Slice() []int32 {
+	return *(*[]int32)(p.p)
 }
 
-// NewAt returns the reflect.Value for a pointer to a field in the struct.
-func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
-	return reflect.NewAt(typ, unsafe.Pointer(uintptr(p)+uintptr(f)))
+// setInt32Slice stores a []int32 to p.
+// The value set is aliased with the input slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) setInt32Slice(v []int32) {
+	*(*[]int32)(p.p) = v
 }
 
-// SetStructPointer writes a *struct field in the struct.
-func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
-	*(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f))) = q
+// TODO: Can we get rid of appendInt32Slice and use setInt32Slice instead?
+func (p pointer) appendInt32Slice(v int32) {
+	s := (*[]int32)(p.p)
+	*s = append(*s, v)
 }
 
-// GetStructPointer reads a *struct field in the struct.
-func structPointer_GetStructPointer(p structPointer, f field) structPointer {
-	return *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toUint64() *uint64 {
+	return (*uint64)(p.p)
 }
-
-// StructPointerSlice the address of a []*struct field in the struct.
-func structPointer_StructPointerSlice(p structPointer, f field) *structPointerSlice {
-	return (*structPointerSlice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toUint64Ptr() **uint64 {
+	return (**uint64)(p.p)
 }
-
-// A structPointerSlice represents a slice of pointers to structs (themselves submessages or groups).
-type structPointerSlice []structPointer
-
-func (v *structPointerSlice) Len() int                  { return len(*v) }
-func (v *structPointerSlice) Index(i int) structPointer { return (*v)[i] }
-func (v *structPointerSlice) Append(p structPointer)    { *v = append(*v, p) }
-
-// A word32 is the address of a "pointer to 32-bit value" field.
-type word32 **uint32
-
-// IsNil reports whether *v is nil.
-func word32_IsNil(p word32) bool {
-	return *p == nil
+func (p pointer) toUint64Slice() *[]uint64 {
+	return (*[]uint64)(p.p)
 }
-
-// Set sets *v to point at a newly allocated word set to x.
-func word32_Set(p word32, o *Buffer, x uint32) {
-	if len(o.uint32s) == 0 {
-		o.uint32s = make([]uint32, uint32PoolSize)
-	}
-	o.uint32s[0] = x
-	*p = &o.uint32s[0]
-	o.uint32s = o.uint32s[1:]
+func (p pointer) toUint32() *uint32 {
+	return (*uint32)(p.p)
 }
-
-// Get gets the value pointed at by *v.
-func word32_Get(p word32) uint32 {
-	return **p
+func (p pointer) toUint32Ptr() **uint32 {
+	return (**uint32)(p.p)
 }
-
-// Word32 returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
-func structPointer_Word32(p structPointer, f field) word32 {
-	return word32((**uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+func (p pointer) toUint32Slice() *[]uint32 {
+	return (*[]uint32)(p.p)
 }
-
-// A word32Val is the address of a 32-bit value field.
-type word32Val *uint32
-
-// Set sets *p to x.
-func word32Val_Set(p word32Val, x uint32) {
-	*p = x
+func (p pointer) toBool() *bool {
+	return (*bool)(p.p)
 }
-
-// Get gets the value pointed at by p.
-func word32Val_Get(p word32Val) uint32 {
-	return *p
+func (p pointer) toBoolPtr() **bool {
+	return (**bool)(p.p)
 }
-
-// Word32Val returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
-func structPointer_Word32Val(p structPointer, f field) word32Val {
-	return word32Val((*uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+func (p pointer) toBoolSlice() *[]bool {
+	return (*[]bool)(p.p)
 }
-
-// A word32Slice is a slice of 32-bit values.
-type word32Slice []uint32
-
-func (v *word32Slice) Append(x uint32)    { *v = append(*v, x) }
-func (v *word32Slice) Len() int           { return len(*v) }
-func (v *word32Slice) Index(i int) uint32 { return (*v)[i] }
-
-// Word32Slice returns the address of a []int32, []uint32, []float32, or []enum field in the struct.
-func structPointer_Word32Slice(p structPointer, f field) *word32Slice {
-	return (*word32Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func (p pointer) toFloat64() *float64 {
+	return (*float64)(p.p)
 }
-
-// word64 is like word32 but for 64-bit values.
-type word64 **uint64
-
-func word64_Set(p word64, o *Buffer, x uint64) {
-	if len(o.uint64s) == 0 {
-		o.uint64s = make([]uint64, uint64PoolSize)
-	}
-	o.uint64s[0] = x
-	*p = &o.uint64s[0]
-	o.uint64s = o.uint64s[1:]
+func (p pointer) toFloat64Ptr() **float64 {
+	return (**float64)(p.p)
 }
-
-func word64_IsNil(p word64) bool {
-	return *p == nil
+func (p pointer) toFloat64Slice() *[]float64 {
+	return (*[]float64)(p.p)
 }
-
-func word64_Get(p word64) uint64 {
-	return **p
+func (p pointer) toFloat32() *float32 {
+	return (*float32)(p.p)
+}
+func (p pointer) toFloat32Ptr() **float32 {
+	return (**float32)(p.p)
+}
+func (p pointer) toFloat32Slice() *[]float32 {
+	return (*[]float32)(p.p)
+}
+func (p pointer) toString() *string {
+	return (*string)(p.p)
+}
+func (p pointer) toStringPtr() **string {
+	return (**string)(p.p)
+}
+func (p pointer) toStringSlice() *[]string {
+	return (*[]string)(p.p)
+}
+func (p pointer) toBytes() *[]byte {
+	return (*[]byte)(p.p)
+}
+func (p pointer) toBytesSlice() *[][]byte {
+	return (*[][]byte)(p.p)
+}
+func (p pointer) toExtensions() *XXX_InternalExtensions {
+	return (*XXX_InternalExtensions)(p.p)
+}
+func (p pointer) toOldExtensions() *map[int32]Extension {
+	return (*map[int32]Extension)(p.p)
 }
 
-func structPointer_Word64(p structPointer, f field) word64 {
-	return word64((**uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+// getPointerSlice loads []*T from p as a []pointer.
+// The value returned is aliased with the original slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) getPointerSlice() []pointer {
+	// Super-tricky - p should point to a []*T where T is a
+	// message type. We load it as []pointer.
+	return *(*[]pointer)(p.p)
 }
 
-// word64Val is like word32Val but for 64-bit values.
-type word64Val *uint64
+// setPointerSlice stores []pointer into p as a []*T.
+// The value set is aliased with the input slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) setPointerSlice(v []pointer) {
+	// Super-tricky - p should point to a []*T where T is a
+	// message type. We store it as []pointer.
+	*(*[]pointer)(p.p) = v
+}
 
-func word64Val_Set(p word64Val, o *Buffer, x uint64) {
-	*p = x
+// getPointer loads the pointer at p and returns it.
+func (p pointer) getPointer() pointer {
+	return pointer{p: *(*unsafe.Pointer)(p.p)}
 }
 
-func word64Val_Get(p word64Val) uint64 {
-	return *p
+// setPointer stores the pointer q at p.
+func (p pointer) setPointer(q pointer) {
+	*(*unsafe.Pointer)(p.p) = q.p
 }
 
-func structPointer_Word64Val(p structPointer, f field) word64Val {
-	return word64Val((*uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+// append q to the slice pointed to by p.
+func (p pointer) appendPointer(q pointer) {
+	s := (*[]unsafe.Pointer)(p.p)
+	*s = append(*s, q.p)
 }
 
-// word64Slice is like word32Slice but for 64-bit values.
-type word64Slice []uint64
+// getInterfacePointer returns a pointer that points to the
+// interface data of the interface pointed by p.
+func (p pointer) getInterfacePointer() pointer {
+	// Super-tricky - read pointer out of data word of interface value.
+	return pointer{p: (*(*[2]unsafe.Pointer)(p.p))[1]}
+}
 
-func (v *word64Slice) Append(x uint64)    { *v = append(*v, x) }
-func (v *word64Slice) Len() int           { return len(*v) }
-func (v *word64Slice) Index(i int) uint64 { return (*v)[i] }
+// asPointerTo returns a reflect.Value that is a pointer to an
+// object of type t stored at p.
+func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
+	return reflect.NewAt(t, p.p)
+}
 
-func structPointer_Word64Slice(p structPointer, f field) *word64Slice {
-	return (*word64Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
+	return (*unmarshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
+	return (*marshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
+	return (*mergeInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
+}
+func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
+	return (*discardInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
+}
+func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
 }
diff --git a/vendor/github.com/golang/protobuf/proto/properties.go b/vendor/github.com/golang/protobuf/proto/properties.go
index ec2289c005..79668ff5c5 100644
--- a/vendor/github.com/golang/protobuf/proto/properties.go
+++ b/vendor/github.com/golang/protobuf/proto/properties.go
@@ -58,42 +58,6 @@ const (
 	WireFixed32    = 5
 )
 
-const startSize = 10 // initial slice/string sizes
-
-// Encoders are defined in encode.go
-// An encoder outputs the full representation of a field, including its
-// tag and encoder type.
-type encoder func(p *Buffer, prop *Properties, base structPointer) error
-
-// A valueEncoder encodes a single integer in a particular encoding.
-type valueEncoder func(o *Buffer, x uint64) error
-
-// Sizers are defined in encode.go
-// A sizer returns the encoded size of a field, including its tag and encoder
-// type.
-type sizer func(prop *Properties, base structPointer) int
-
-// A valueSizer returns the encoded size of a single integer in a particular
-// encoding.
-type valueSizer func(x uint64) int
-
-// Decoders are defined in decode.go
-// A decoder creates a value from its wire representation.
-// Unrecognized subelements are saved in unrec.
-type decoder func(p *Buffer, prop *Properties, base structPointer) error
-
-// A valueDecoder decodes a single integer in a particular encoding.
-type valueDecoder func(o *Buffer) (x uint64, err error)
-
-// A oneofMarshaler does the marshaling for all oneof fields in a message.
-type oneofMarshaler func(Message, *Buffer) error
-
-// A oneofUnmarshaler does the unmarshaling for a oneof field in a message.
-type oneofUnmarshaler func(Message, int, int, *Buffer) (bool, error)
-
-// A oneofSizer does the sizing for all oneof fields in a message.
-type oneofSizer func(Message) int
-
 // tagMap is an optimization over map[int]int for typical protocol buffer
 // use-cases. Encoded protocol buffers are often in tag order with small tag
 // numbers.
@@ -140,13 +104,6 @@ type StructProperties struct {
 	decoderTags      tagMap         // map from proto tag to struct field number
 	decoderOrigNames map[string]int // map from original name to struct field number
 	order            []int          // list of struct field numbers in tag order
-	unrecField       field          // field id of the XXX_unrecognized []byte field
-	extendable       bool           // is this an extendable proto
-
-	oneofMarshaler   oneofMarshaler
-	oneofUnmarshaler oneofUnmarshaler
-	oneofSizer       oneofSizer
-	stype            reflect.Type
 
 	// OneofTypes contains information about the oneof fields in this message.
 	// It is keyed by the original name of a field.
@@ -182,41 +139,24 @@ type Properties struct {
 	Repeated bool
 	Packed   bool   // relevant for repeated primitives only
 	Enum     string // set for enum types only
-	proto3   bool   // whether this is known to be a proto3 field; set for []byte only
+	proto3   bool   // whether this is known to be a proto3 field
 	oneof    bool   // whether this is a oneof field
 
 	Default    string // default value
 	HasDefault bool   // whether an explicit default was provided
-	def_uint64 uint64
-
-	enc           encoder
-	valEnc        valueEncoder // set for bool and numeric types only
-	field         field
-	tagcode       []byte // encoding of EncodeVarint((Tag<<3)|WireType)
-	tagbuf        [8]byte
-	stype         reflect.Type      // set for struct types only
-	sprop         *StructProperties // set for struct types only
-	isMarshaler   bool
-	isUnmarshaler bool
-
-	mtype    reflect.Type // set for map types only
-	mkeyprop *Properties  // set for map types only
-	mvalprop *Properties  // set for map types only
-
-	size    sizer
-	valSize valueSizer // set for bool and numeric types only
-
-	dec    decoder
-	valDec valueDecoder // set for bool and numeric types only
-
-	// If this is a packable field, this will be the decoder for the packed version of the field.
-	packedDec decoder
+
+	stype reflect.Type      // set for struct types only
+	sprop *StructProperties // set for struct types only
+
+	mtype      reflect.Type // set for map types only
+	MapKeyProp *Properties  // set for map types only
+	MapValProp *Properties  // set for map types only
 }
 
 // String formats the properties in the protobuf struct field tag style.
 func (p *Properties) String() string {
 	s := p.Wire
-	s = ","
+	s += ","
 	s += strconv.Itoa(p.Tag)
 	if p.Required {
 		s += ",req"
@@ -262,29 +202,14 @@ func (p *Properties) Parse(s string) {
 	switch p.Wire {
 	case "varint":
 		p.WireType = WireVarint
-		p.valEnc = (*Buffer).EncodeVarint
-		p.valDec = (*Buffer).DecodeVarint
-		p.valSize = sizeVarint
 	case "fixed32":
 		p.WireType = WireFixed32
-		p.valEnc = (*Buffer).EncodeFixed32
-		p.valDec = (*Buffer).DecodeFixed32
-		p.valSize = sizeFixed32
 	case "fixed64":
 		p.WireType = WireFixed64
-		p.valEnc = (*Buffer).EncodeFixed64
-		p.valDec = (*Buffer).DecodeFixed64
-		p.valSize = sizeFixed64
 	case "zigzag32":
 		p.WireType = WireVarint
-		p.valEnc = (*Buffer).EncodeZigzag32
-		p.valDec = (*Buffer).DecodeZigzag32
-		p.valSize = sizeZigzag32
 	case "zigzag64":
 		p.WireType = WireVarint
-		p.valEnc = (*Buffer).EncodeZigzag64
-		p.valDec = (*Buffer).DecodeZigzag64
-		p.valSize = sizeZigzag64
 	case "bytes", "group":
 		p.WireType = WireBytes
 		// no numeric converter for non-numeric types
@@ -299,6 +224,7 @@ func (p *Properties) Parse(s string) {
 		return
 	}
 
+outer:
 	for i := 2; i < len(fields); i++ {
 		f := fields[i]
 		switch {
@@ -326,255 +252,40 @@ func (p *Properties) Parse(s string) {
 			if i+1 < len(fields) {
 				// Commas aren't escaped, and def is always last.
 				p.Default += "," + strings.Join(fields[i+1:], ",")
-				break
+				break outer
 			}
 		}
 	}
 }
 
-func logNoSliceEnc(t1, t2 reflect.Type) {
-	fmt.Fprintf(os.Stderr, "proto: no slice oenc for %T = []%T\n", t1, t2)
-}
-
 var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem()
 
-// Initialize the fields for encoding and decoding.
-func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
-	p.enc = nil
-	p.dec = nil
-	p.size = nil
-
+// setFieldProps initializes the field properties for submessages and maps.
+func (p *Properties) setFieldProps(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
 	switch t1 := typ; t1.Kind() {
-	default:
-		fmt.Fprintf(os.Stderr, "proto: no coders for %v\n", t1)
-
-	// proto3 scalar types
-
-	case reflect.Bool:
-		p.enc = (*Buffer).enc_proto3_bool
-		p.dec = (*Buffer).dec_proto3_bool
-		p.size = size_proto3_bool
-	case reflect.Int32:
-		p.enc = (*Buffer).enc_proto3_int32
-		p.dec = (*Buffer).dec_proto3_int32
-		p.size = size_proto3_int32
-	case reflect.Uint32:
-		p.enc = (*Buffer).enc_proto3_uint32
-		p.dec = (*Buffer).dec_proto3_int32 // can reuse
-		p.size = size_proto3_uint32
-	case reflect.Int64, reflect.Uint64:
-		p.enc = (*Buffer).enc_proto3_int64
-		p.dec = (*Buffer).dec_proto3_int64
-		p.size = size_proto3_int64
-	case reflect.Float32:
-		p.enc = (*Buffer).enc_proto3_uint32 // can just treat them as bits
-		p.dec = (*Buffer).dec_proto3_int32
-		p.size = size_proto3_uint32
-	case reflect.Float64:
-		p.enc = (*Buffer).enc_proto3_int64 // can just treat them as bits
-		p.dec = (*Buffer).dec_proto3_int64
-		p.size = size_proto3_int64
-	case reflect.String:
-		p.enc = (*Buffer).enc_proto3_string
-		p.dec = (*Buffer).dec_proto3_string
-		p.size = size_proto3_string
-
 	case reflect.Ptr:
-		switch t2 := t1.Elem(); t2.Kind() {
-		default:
-			fmt.Fprintf(os.Stderr, "proto: no encoder function for %v -> %v\n", t1, t2)
-			break
-		case reflect.Bool:
-			p.enc = (*Buffer).enc_bool
-			p.dec = (*Buffer).dec_bool
-			p.size = size_bool
-		case reflect.Int32:
-			p.enc = (*Buffer).enc_int32
-			p.dec = (*Buffer).dec_int32
-			p.size = size_int32
-		case reflect.Uint32:
-			p.enc = (*Buffer).enc_uint32
-			p.dec = (*Buffer).dec_int32 // can reuse
-			p.size = size_uint32
-		case reflect.Int64, reflect.Uint64:
-			p.enc = (*Buffer).enc_int64
-			p.dec = (*Buffer).dec_int64
-			p.size = size_int64
-		case reflect.Float32:
-			p.enc = (*Buffer).enc_uint32 // can just treat them as bits
-			p.dec = (*Buffer).dec_int32
-			p.size = size_uint32
-		case reflect.Float64:
-			p.enc = (*Buffer).enc_int64 // can just treat them as bits
-			p.dec = (*Buffer).dec_int64
-			p.size = size_int64
-		case reflect.String:
-			p.enc = (*Buffer).enc_string
-			p.dec = (*Buffer).dec_string
-			p.size = size_string
-		case reflect.Struct:
+		if t1.Elem().Kind() == reflect.Struct {
 			p.stype = t1.Elem()
-			p.isMarshaler = isMarshaler(t1)
-			p.isUnmarshaler = isUnmarshaler(t1)
-			if p.Wire == "bytes" {
-				p.enc = (*Buffer).enc_struct_message
-				p.dec = (*Buffer).dec_struct_message
-				p.size = size_struct_message
-			} else {
-				p.enc = (*Buffer).enc_struct_group
-				p.dec = (*Buffer).dec_struct_group
-				p.size = size_struct_group
-			}
 		}
 
 	case reflect.Slice:
-		switch t2 := t1.Elem(); t2.Kind() {
-		default:
-			logNoSliceEnc(t1, t2)
-			break
-		case reflect.Bool:
-			if p.Packed {
-				p.enc = (*Buffer).enc_slice_packed_bool
-				p.size = size_slice_packed_bool
-			} else {
-				p.enc = (*Buffer).enc_slice_bool
-				p.size = size_slice_bool
-			}
-			p.dec = (*Buffer).dec_slice_bool
-			p.packedDec = (*Buffer).dec_slice_packed_bool
-		case reflect.Int32:
-			if p.Packed {
-				p.enc = (*Buffer).enc_slice_packed_int32
-				p.size = size_slice_packed_int32
-			} else {
-				p.enc = (*Buffer).enc_slice_int32
-				p.size = size_slice_int32
-			}
-			p.dec = (*Buffer).dec_slice_int32
-			p.packedDec = (*Buffer).dec_slice_packed_int32
-		case reflect.Uint32:
-			if p.Packed {
-				p.enc = (*Buffer).enc_slice_packed_uint32
-				p.size = size_slice_packed_uint32
-			} else {
-				p.enc = (*Buffer).enc_slice_uint32
-				p.size = size_slice_uint32
-			}
-			p.dec = (*Buffer).dec_slice_int32
-			p.packedDec = (*Buffer).dec_slice_packed_int32
-		case reflect.Int64, reflect.Uint64:
-			if p.Packed {
-				p.enc = (*Buffer).enc_slice_packed_int64
-				p.size = size_slice_packed_int64
-			} else {
-				p.enc = (*Buffer).enc_slice_int64
-				p.size = size_slice_int64
-			}
-			p.dec = (*Buffer).dec_slice_int64
-			p.packedDec = (*Buffer).dec_slice_packed_int64
-		case reflect.Uint8:
-			p.dec = (*Buffer).dec_slice_byte
-			if p.proto3 {
-				p.enc = (*Buffer).enc_proto3_slice_byte
-				p.size = size_proto3_slice_byte
-			} else {
-				p.enc = (*Buffer).enc_slice_byte
-				p.size = size_slice_byte
-			}
-		case reflect.Float32, reflect.Float64:
-			switch t2.Bits() {
-			case 32:
-				// can just treat them as bits
-				if p.Packed {
-					p.enc = (*Buffer).enc_slice_packed_uint32
-					p.size = size_slice_packed_uint32
-				} else {
-					p.enc = (*Buffer).enc_slice_uint32
-					p.size = size_slice_uint32
-				}
-				p.dec = (*Buffer).dec_slice_int32
-				p.packedDec = (*Buffer).dec_slice_packed_int32
-			case 64:
-				// can just treat them as bits
-				if p.Packed {
-					p.enc = (*Buffer).enc_slice_packed_int64
-					p.size = size_slice_packed_int64
-				} else {
-					p.enc = (*Buffer).enc_slice_int64
-					p.size = size_slice_int64
-				}
-				p.dec = (*Buffer).dec_slice_int64
-				p.packedDec = (*Buffer).dec_slice_packed_int64
-			default:
-				logNoSliceEnc(t1, t2)
-				break
-			}
-		case reflect.String:
-			p.enc = (*Buffer).enc_slice_string
-			p.dec = (*Buffer).dec_slice_string
-			p.size = size_slice_string
-		case reflect.Ptr:
-			switch t3 := t2.Elem(); t3.Kind() {
-			default:
-				fmt.Fprintf(os.Stderr, "proto: no ptr oenc for %T -> %T -> %T\n", t1, t2, t3)
-				break
-			case reflect.Struct:
-				p.stype = t2.Elem()
-				p.isMarshaler = isMarshaler(t2)
-				p.isUnmarshaler = isUnmarshaler(t2)
-				if p.Wire == "bytes" {
-					p.enc = (*Buffer).enc_slice_struct_message
-					p.dec = (*Buffer).dec_slice_struct_message
-					p.size = size_slice_struct_message
-				} else {
-					p.enc = (*Buffer).enc_slice_struct_group
-					p.dec = (*Buffer).dec_slice_struct_group
-					p.size = size_slice_struct_group
-				}
-			}
-		case reflect.Slice:
-			switch t2.Elem().Kind() {
-			default:
-				fmt.Fprintf(os.Stderr, "proto: no slice elem oenc for %T -> %T -> %T\n", t1, t2, t2.Elem())
-				break
-			case reflect.Uint8:
-				p.enc = (*Buffer).enc_slice_slice_byte
-				p.dec = (*Buffer).dec_slice_slice_byte
-				p.size = size_slice_slice_byte
-			}
+		if t2 := t1.Elem(); t2.Kind() == reflect.Ptr && t2.Elem().Kind() == reflect.Struct {
+			p.stype = t2.Elem()
 		}
 
 	case reflect.Map:
-		p.enc = (*Buffer).enc_new_map
-		p.dec = (*Buffer).dec_new_map
-		p.size = size_new_map
-
 		p.mtype = t1
-		p.mkeyprop = &Properties{}
-		p.mkeyprop.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
-		p.mvalprop = &Properties{}
+		p.MapKeyProp = &Properties{}
+		p.MapKeyProp.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
+		p.MapValProp = &Properties{}
 		vtype := p.mtype.Elem()
 		if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice {
 			// The value type is not a message (*T) or bytes ([]byte),
 			// so we need encoders for the pointer to this type.
 			vtype = reflect.PtrTo(vtype)
 		}
-		p.mvalprop.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
-	}
-
-	// precalculate tag code
-	wire := p.WireType
-	if p.Packed {
-		wire = WireBytes
+		p.MapValProp.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
 	}
-	x := uint32(p.Tag)<<3 | uint32(wire)
-	i := 0
-	for i = 0; x > 127; i++ {
-		p.tagbuf[i] = 0x80 | uint8(x&0x7F)
-		x >>= 7
-	}
-	p.tagbuf[i] = uint8(x)
-	p.tagcode = p.tagbuf[0 : i+1]
 
 	if p.stype != nil {
 		if lockGetProp {
@@ -586,32 +297,9 @@ func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lock
 }
 
 var (
-	marshalerType   = reflect.TypeOf((*Marshaler)(nil)).Elem()
-	unmarshalerType = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+	marshalerType = reflect.TypeOf((*Marshaler)(nil)).Elem()
 )
 
-// isMarshaler reports whether type t implements Marshaler.
-func isMarshaler(t reflect.Type) bool {
-	// We're checking for (likely) pointer-receiver methods
-	// so if t is not a pointer, something is very wrong.
-	// The calls above only invoke isMarshaler on pointer types.
-	if t.Kind() != reflect.Ptr {
-		panic("proto: misuse of isMarshaler")
-	}
-	return t.Implements(marshalerType)
-}
-
-// isUnmarshaler reports whether type t implements Unmarshaler.
-func isUnmarshaler(t reflect.Type) bool {
-	// We're checking for (likely) pointer-receiver methods
-	// so if t is not a pointer, something is very wrong.
-	// The calls above only invoke isUnmarshaler on pointer types.
-	if t.Kind() != reflect.Ptr {
-		panic("proto: misuse of isUnmarshaler")
-	}
-	return t.Implements(unmarshalerType)
-}
-
 // Init populates the properties from a protocol buffer struct tag.
 func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) {
 	p.init(typ, name, tag, f, true)
@@ -621,14 +309,11 @@ func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructF
 	// "bytes,49,opt,def=hello!"
 	p.Name = name
 	p.OrigName = name
-	if f != nil {
-		p.field = toField(f)
-	}
 	if tag == "" {
 		return
 	}
 	p.Parse(tag)
-	p.setEncAndDec(typ, f, lockGetProp)
+	p.setFieldProps(typ, f, lockGetProp)
 }
 
 var (
@@ -649,9 +334,6 @@ func GetProperties(t reflect.Type) *StructProperties {
 	sprop, ok := propertiesMap[t]
 	propertiesMu.RUnlock()
 	if ok {
-		if collectStats {
-			stats.Chit++
-		}
 		return sprop
 	}
 
@@ -661,26 +343,26 @@ func GetProperties(t reflect.Type) *StructProperties {
 	return sprop
 }
 
+type (
+	oneofFuncsIface interface {
+		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{})
+	}
+	oneofWrappersIface interface {
+		XXX_OneofWrappers() []interface{}
+	}
+)
+
 // getPropertiesLocked requires that propertiesMu is held.
 func getPropertiesLocked(t reflect.Type) *StructProperties {
 	if prop, ok := propertiesMap[t]; ok {
-		if collectStats {
-			stats.Chit++
-		}
 		return prop
 	}
-	if collectStats {
-		stats.Cmiss++
-	}
 
 	prop := new(StructProperties)
 	// in case of recursive protos, fill this in now.
 	propertiesMap[t] = prop
 
 	// build properties
-	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType) ||
-		reflect.PtrTo(t).Implements(extendableProtoV1Type)
-	prop.unrecField = invalidField
 	prop.Prop = make([]*Properties, t.NumField())
 	prop.order = make([]int, t.NumField())
 
@@ -690,17 +372,6 @@ func getPropertiesLocked(t reflect.Type) *StructProperties {
 		name := f.Name
 		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
 
-		if f.Name == "XXX_InternalExtensions" { // special case
-			p.enc = (*Buffer).enc_exts
-			p.dec = nil // not needed
-			p.size = size_exts
-		} else if f.Name == "XXX_extensions" { // special case
-			p.enc = (*Buffer).enc_map
-			p.dec = nil // not needed
-			p.size = size_map
-		} else if f.Name == "XXX_unrecognized" { // special case
-			prop.unrecField = toField(&f)
-		}
 		oneof := f.Tag.Get("protobuf_oneof") // special case
 		if oneof != "" {
 			// Oneof fields don't use the traditional protobuf tag.
@@ -715,22 +386,19 @@ func getPropertiesLocked(t reflect.Type) *StructProperties {
 			}
 			print("\n")
 		}
-		if p.enc == nil && !strings.HasPrefix(f.Name, "XXX_") && oneof == "" {
-			fmt.Fprintln(os.Stderr, "proto: no encoder for", f.Name, f.Type.String(), "[GetProperties]")
-		}
 	}
 
 	// Re-order prop.order.
 	sort.Sort(prop)
 
-	type oneofMessage interface {
-		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{})
+	var oots []interface{}
+	switch m := reflect.Zero(reflect.PtrTo(t)).Interface().(type) {
+	case oneofFuncsIface:
+		_, _, _, oots = m.XXX_OneofFuncs()
+	case oneofWrappersIface:
+		oots = m.XXX_OneofWrappers()
 	}
-	if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok {
-		var oots []interface{}
-		prop.oneofMarshaler, prop.oneofUnmarshaler, prop.oneofSizer, oots = om.XXX_OneofFuncs()
-		prop.stype = t
-
+	if len(oots) > 0 {
 		// Interpret oneof metadata.
 		prop.OneofTypes = make(map[string]*OneofProperties)
 		for _, oot := range oots {
@@ -779,30 +447,6 @@ func getPropertiesLocked(t reflect.Type) *StructProperties {
 	return prop
 }
 
-// Return the Properties object for the x[0]'th field of the structure.
-func propByIndex(t reflect.Type, x []int) *Properties {
-	if len(x) != 1 {
-		fmt.Fprintf(os.Stderr, "proto: field index dimension %d (not 1) for type %s\n", len(x), t)
-		return nil
-	}
-	prop := GetProperties(t)
-	return prop.Prop[x[0]]
-}
-
-// Get the address and type of a pointer to a struct from an interface.
-func getbase(pb Message) (t reflect.Type, b structPointer, err error) {
-	if pb == nil {
-		err = ErrNil
-		return
-	}
-	// get the reflect type of the pointer to the struct.
-	t = reflect.TypeOf(pb)
-	// get the address of the struct.
-	value := reflect.ValueOf(pb)
-	b = toStructPointer(value)
-	return
-}
-
 // A global registry of enum types.
 // The generated code will register the generated maps by calling RegisterEnum.
 
@@ -826,20 +470,42 @@ func EnumValueMap(enumType string) map[string]int32 {
 // A registry of all linked message types.
 // The string is a fully-qualified proto name ("pkg.Message").
 var (
-	protoTypes    = make(map[string]reflect.Type)
-	revProtoTypes = make(map[reflect.Type]string)
+	protoTypedNils = make(map[string]Message)      // a map from proto names to typed nil pointers
+	protoMapTypes  = make(map[string]reflect.Type) // a map from proto names to map types
+	revProtoTypes  = make(map[reflect.Type]string)
 )
 
 // RegisterType is called from generated code and maps from the fully qualified
 // proto name to the type (pointer to struct) of the protocol buffer.
 func RegisterType(x Message, name string) {
-	if _, ok := protoTypes[name]; ok {
+	if _, ok := protoTypedNils[name]; ok {
 		// TODO: Some day, make this a panic.
 		log.Printf("proto: duplicate proto type registered: %s", name)
 		return
 	}
 	t := reflect.TypeOf(x)
-	protoTypes[name] = t
+	if v := reflect.ValueOf(x); v.Kind() == reflect.Ptr && v.Pointer() == 0 {
+		// Generated code always calls RegisterType with nil x.
+		// This check is just for extra safety.
+		protoTypedNils[name] = x
+	} else {
+		protoTypedNils[name] = reflect.Zero(t).Interface().(Message)
+	}
+	revProtoTypes[t] = name
+}
+
+// RegisterMapType is called from generated code and maps from the fully qualified
+// proto name to the native map type of the proto map definition.
+func RegisterMapType(x interface{}, name string) {
+	if reflect.TypeOf(x).Kind() != reflect.Map {
+		panic(fmt.Sprintf("RegisterMapType(%T, %q); want map", x, name))
+	}
+	if _, ok := protoMapTypes[name]; ok {
+		log.Printf("proto: duplicate proto type registered: %s", name)
+		return
+	}
+	t := reflect.TypeOf(x)
+	protoMapTypes[name] = t
 	revProtoTypes[t] = name
 }
 
@@ -855,7 +521,14 @@ func MessageName(x Message) string {
 }
 
 // MessageType returns the message type (pointer to struct) for a named message.
-func MessageType(name string) reflect.Type { return protoTypes[name] }
+// The type is not guaranteed to implement proto.Message if the name refers to a
+// map entry.
+func MessageType(name string) reflect.Type {
+	if t, ok := protoTypedNils[name]; ok {
+		return reflect.TypeOf(t)
+	}
+	return protoMapTypes[name]
+}
 
 // A registry of all linked proto files.
 var (
diff --git a/vendor/github.com/golang/protobuf/proto/table_marshal.go b/vendor/github.com/golang/protobuf/proto/table_marshal.go
new file mode 100644
index 0000000000..5cb11fa955
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/table_marshal.go
@@ -0,0 +1,2776 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2016 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"unicode/utf8"
+)
+
+// a sizer takes a pointer to a field and the size of its tag, computes the size of
+// the encoded data.
+type sizer func(pointer, int) int
+
+// a marshaler takes a byte slice, a pointer to a field, and its tag (in wire format),
+// marshals the field to the end of the slice, returns the slice and error (if any).
+type marshaler func(b []byte, ptr pointer, wiretag uint64, deterministic bool) ([]byte, error)
+
+// marshalInfo is the information used for marshaling a message.
+type marshalInfo struct {
+	typ          reflect.Type
+	fields       []*marshalFieldInfo
+	unrecognized field                      // offset of XXX_unrecognized
+	extensions   field                      // offset of XXX_InternalExtensions
+	v1extensions field                      // offset of XXX_extensions
+	sizecache    field                      // offset of XXX_sizecache
+	initialized  int32                      // 0 -- only typ is set, 1 -- fully initialized
+	messageset   bool                       // uses message set wire format
+	hasmarshaler bool                       // has custom marshaler
+	sync.RWMutex                            // protect extElems map, also for initialization
+	extElems     map[int32]*marshalElemInfo // info of extension elements
+}
+
+// marshalFieldInfo is the information used for marshaling a field of a message.
+type marshalFieldInfo struct {
+	field      field
+	wiretag    uint64 // tag in wire format
+	tagsize    int    // size of tag in wire format
+	sizer      sizer
+	marshaler  marshaler
+	isPointer  bool
+	required   bool                              // field is required
+	name       string                            // name of the field, for error reporting
+	oneofElems map[reflect.Type]*marshalElemInfo // info of oneof elements
+}
+
+// marshalElemInfo is the information used for marshaling an extension or oneof element.
+type marshalElemInfo struct {
+	wiretag   uint64 // tag in wire format
+	tagsize   int    // size of tag in wire format
+	sizer     sizer
+	marshaler marshaler
+	isptr     bool // elem is pointer typed, thus interface of this type is a direct interface (extension only)
+	deref     bool // dereference the pointer before operating on it; implies isptr
+}
+
+var (
+	marshalInfoMap  = map[reflect.Type]*marshalInfo{}
+	marshalInfoLock sync.Mutex
+)
+
+// getMarshalInfo returns the information to marshal a given type of message.
+// The info it returns may not necessarily initialized.
+// t is the type of the message (NOT the pointer to it).
+func getMarshalInfo(t reflect.Type) *marshalInfo {
+	marshalInfoLock.Lock()
+	u, ok := marshalInfoMap[t]
+	if !ok {
+		u = &marshalInfo{typ: t}
+		marshalInfoMap[t] = u
+	}
+	marshalInfoLock.Unlock()
+	return u
+}
+
+// Size is the entry point from generated code,
+// and should be ONLY called by generated code.
+// It computes the size of encoded data of msg.
+// a is a pointer to a place to store cached marshal info.
+func (a *InternalMessageInfo) Size(msg Message) int {
+	u := getMessageMarshalInfo(msg, a)
+	ptr := toPointer(&msg)
+	if ptr.isNil() {
+		// We get here if msg is a typed nil ((*SomeMessage)(nil)),
+		// so it satisfies the interface, and msg == nil wouldn't
+		// catch it. We don't want crash in this case.
+		return 0
+	}
+	return u.size(ptr)
+}
+
+// Marshal is the entry point from generated code,
+// and should be ONLY called by generated code.
+// It marshals msg to the end of b.
+// a is a pointer to a place to store cached marshal info.
+func (a *InternalMessageInfo) Marshal(b []byte, msg Message, deterministic bool) ([]byte, error) {
+	u := getMessageMarshalInfo(msg, a)
+	ptr := toPointer(&msg)
+	if ptr.isNil() {
+		// We get here if msg is a typed nil ((*SomeMessage)(nil)),
+		// so it satisfies the interface, and msg == nil wouldn't
+		// catch it. We don't want crash in this case.
+		return b, ErrNil
+	}
+	return u.marshal(b, ptr, deterministic)
+}
+
+func getMessageMarshalInfo(msg interface{}, a *InternalMessageInfo) *marshalInfo {
+	// u := a.marshal, but atomically.
+	// We use an atomic here to ensure memory consistency.
+	u := atomicLoadMarshalInfo(&a.marshal)
+	if u == nil {
+		// Get marshal information from type of message.
+		t := reflect.ValueOf(msg).Type()
+		if t.Kind() != reflect.Ptr {
+			panic(fmt.Sprintf("cannot handle non-pointer message type %v", t))
+		}
+		u = getMarshalInfo(t.Elem())
+		// Store it in the cache for later users.
+		// a.marshal = u, but atomically.
+		atomicStoreMarshalInfo(&a.marshal, u)
+	}
+	return u
+}
+
+// size is the main function to compute the size of the encoded data of a message.
+// ptr is the pointer to the message.
+func (u *marshalInfo) size(ptr pointer) int {
+	if atomic.LoadInt32(&u.initialized) == 0 {
+		u.computeMarshalInfo()
+	}
+
+	// If the message can marshal itself, let it do it, for compatibility.
+	// NOTE: This is not efficient.
+	if u.hasmarshaler {
+		m := ptr.asPointerTo(u.typ).Interface().(Marshaler)
+		b, _ := m.Marshal()
+		return len(b)
+	}
+
+	n := 0
+	for _, f := range u.fields {
+		if f.isPointer && ptr.offset(f.field).getPointer().isNil() {
+			// nil pointer always marshals to nothing
+			continue
+		}
+		n += f.sizer(ptr.offset(f.field), f.tagsize)
+	}
+	if u.extensions.IsValid() {
+		e := ptr.offset(u.extensions).toExtensions()
+		if u.messageset {
+			n += u.sizeMessageSet(e)
+		} else {
+			n += u.sizeExtensions(e)
+		}
+	}
+	if u.v1extensions.IsValid() {
+		m := *ptr.offset(u.v1extensions).toOldExtensions()
+		n += u.sizeV1Extensions(m)
+	}
+	if u.unrecognized.IsValid() {
+		s := *ptr.offset(u.unrecognized).toBytes()
+		n += len(s)
+	}
+	// cache the result for use in marshal
+	if u.sizecache.IsValid() {
+		atomic.StoreInt32(ptr.offset(u.sizecache).toInt32(), int32(n))
+	}
+	return n
+}
+
+// cachedsize gets the size from cache. If there is no cache (i.e. message is not generated),
+// fall back to compute the size.
+func (u *marshalInfo) cachedsize(ptr pointer) int {
+	if u.sizecache.IsValid() {
+		return int(atomic.LoadInt32(ptr.offset(u.sizecache).toInt32()))
+	}
+	return u.size(ptr)
+}
+
+// marshal is the main function to marshal a message. It takes a byte slice and appends
+// the encoded data to the end of the slice, returns the slice and error (if any).
+// ptr is the pointer to the message.
+// If deterministic is true, map is marshaled in deterministic order.
+func (u *marshalInfo) marshal(b []byte, ptr pointer, deterministic bool) ([]byte, error) {
+	if atomic.LoadInt32(&u.initialized) == 0 {
+		u.computeMarshalInfo()
+	}
+
+	// If the message can marshal itself, let it do it, for compatibility.
+	// NOTE: This is not efficient.
+	if u.hasmarshaler {
+		m := ptr.asPointerTo(u.typ).Interface().(Marshaler)
+		b1, err := m.Marshal()
+		b = append(b, b1...)
+		return b, err
+	}
+
+	var err, errLater error
+	// The old marshaler encodes extensions at beginning.
+	if u.extensions.IsValid() {
+		e := ptr.offset(u.extensions).toExtensions()
+		if u.messageset {
+			b, err = u.appendMessageSet(b, e, deterministic)
+		} else {
+			b, err = u.appendExtensions(b, e, deterministic)
+		}
+		if err != nil {
+			return b, err
+		}
+	}
+	if u.v1extensions.IsValid() {
+		m := *ptr.offset(u.v1extensions).toOldExtensions()
+		b, err = u.appendV1Extensions(b, m, deterministic)
+		if err != nil {
+			return b, err
+		}
+	}
+	for _, f := range u.fields {
+		if f.required {
+			if ptr.offset(f.field).getPointer().isNil() {
+				// Required field is not set.
+				// We record the error but keep going, to give a complete marshaling.
+				if errLater == nil {
+					errLater = &RequiredNotSetError{f.name}
+				}
+				continue
+			}
+		}
+		if f.isPointer && ptr.offset(f.field).getPointer().isNil() {
+			// nil pointer always marshals to nothing
+			continue
+		}
+		b, err = f.marshaler(b, ptr.offset(f.field), f.wiretag, deterministic)
+		if err != nil {
+			if err1, ok := err.(*RequiredNotSetError); ok {
+				// Required field in submessage is not set.
+				// We record the error but keep going, to give a complete marshaling.
+				if errLater == nil {
+					errLater = &RequiredNotSetError{f.name + "." + err1.field}
+				}
+				continue
+			}
+			if err == errRepeatedHasNil {
+				err = errors.New("proto: repeated field " + f.name + " has nil element")
+			}
+			if err == errInvalidUTF8 {
+				if errLater == nil {
+					fullName := revProtoTypes[reflect.PtrTo(u.typ)] + "." + f.name
+					errLater = &invalidUTF8Error{fullName}
+				}
+				continue
+			}
+			return b, err
+		}
+	}
+	if u.unrecognized.IsValid() {
+		s := *ptr.offset(u.unrecognized).toBytes()
+		b = append(b, s...)
+	}
+	return b, errLater
+}
+
+// computeMarshalInfo initializes the marshal info.
+func (u *marshalInfo) computeMarshalInfo() {
+	u.Lock()
+	defer u.Unlock()
+	if u.initialized != 0 { // non-atomic read is ok as it is protected by the lock
+		return
+	}
+
+	t := u.typ
+	u.unrecognized = invalidField
+	u.extensions = invalidField
+	u.v1extensions = invalidField
+	u.sizecache = invalidField
+
+	// If the message can marshal itself, let it do it, for compatibility.
+	// NOTE: This is not efficient.
+	if reflect.PtrTo(t).Implements(marshalerType) {
+		u.hasmarshaler = true
+		atomic.StoreInt32(&u.initialized, 1)
+		return
+	}
+
+	// get oneof implementers
+	var oneofImplementers []interface{}
+	switch m := reflect.Zero(reflect.PtrTo(t)).Interface().(type) {
+	case oneofFuncsIface:
+		_, _, _, oneofImplementers = m.XXX_OneofFuncs()
+	case oneofWrappersIface:
+		oneofImplementers = m.XXX_OneofWrappers()
+	}
+
+	n := t.NumField()
+
+	// deal with XXX fields first
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		if !strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		switch f.Name {
+		case "XXX_sizecache":
+			u.sizecache = toField(&f)
+		case "XXX_unrecognized":
+			u.unrecognized = toField(&f)
+		case "XXX_InternalExtensions":
+			u.extensions = toField(&f)
+			u.messageset = f.Tag.Get("protobuf_messageset") == "1"
+		case "XXX_extensions":
+			u.v1extensions = toField(&f)
+		case "XXX_NoUnkeyedLiteral":
+			// nothing to do
+		default:
+			panic("unknown XXX field: " + f.Name)
+		}
+		n--
+	}
+
+	// normal fields
+	fields := make([]marshalFieldInfo, n) // batch allocation
+	u.fields = make([]*marshalFieldInfo, 0, n)
+	for i, j := 0, 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		field := &fields[j]
+		j++
+		field.name = f.Name
+		u.fields = append(u.fields, field)
+		if f.Tag.Get("protobuf_oneof") != "" {
+			field.computeOneofFieldInfo(&f, oneofImplementers)
+			continue
+		}
+		if f.Tag.Get("protobuf") == "" {
+			// field has no tag (not in generated message), ignore it
+			u.fields = u.fields[:len(u.fields)-1]
+			j--
+			continue
+		}
+		field.computeMarshalFieldInfo(&f)
+	}
+
+	// fields are marshaled in tag order on the wire.
+	sort.Sort(byTag(u.fields))
+
+	atomic.StoreInt32(&u.initialized, 1)
+}
+
+// helper for sorting fields by tag
+type byTag []*marshalFieldInfo
+
+func (a byTag) Len() int           { return len(a) }
+func (a byTag) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a byTag) Less(i, j int) bool { return a[i].wiretag < a[j].wiretag }
+
+// getExtElemInfo returns the information to marshal an extension element.
+// The info it returns is initialized.
+func (u *marshalInfo) getExtElemInfo(desc *ExtensionDesc) *marshalElemInfo {
+	// get from cache first
+	u.RLock()
+	e, ok := u.extElems[desc.Field]
+	u.RUnlock()
+	if ok {
+		return e
+	}
+
+	t := reflect.TypeOf(desc.ExtensionType) // pointer or slice to basic type or struct
+	tags := strings.Split(desc.Tag, ",")
+	tag, err := strconv.Atoi(tags[1])
+	if err != nil {
+		panic("tag is not an integer")
+	}
+	wt := wiretype(tags[0])
+	if t.Kind() == reflect.Ptr && t.Elem().Kind() != reflect.Struct {
+		t = t.Elem()
+	}
+	sizer, marshaler := typeMarshaler(t, tags, false, false)
+	var deref bool
+	if t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8 {
+		t = reflect.PtrTo(t)
+		deref = true
+	}
+	e = &marshalElemInfo{
+		wiretag:   uint64(tag)<<3 | wt,
+		tagsize:   SizeVarint(uint64(tag) << 3),
+		sizer:     sizer,
+		marshaler: marshaler,
+		isptr:     t.Kind() == reflect.Ptr,
+		deref:     deref,
+	}
+
+	// update cache
+	u.Lock()
+	if u.extElems == nil {
+		u.extElems = make(map[int32]*marshalElemInfo)
+	}
+	u.extElems[desc.Field] = e
+	u.Unlock()
+	return e
+}
+
+// computeMarshalFieldInfo fills up the information to marshal a field.
+func (fi *marshalFieldInfo) computeMarshalFieldInfo(f *reflect.StructField) {
+	// parse protobuf tag of the field.
+	// tag has format of "bytes,49,opt,name=foo,def=hello!"
+	tags := strings.Split(f.Tag.Get("protobuf"), ",")
+	if tags[0] == "" {
+		return
+	}
+	tag, err := strconv.Atoi(tags[1])
+	if err != nil {
+		panic("tag is not an integer")
+	}
+	wt := wiretype(tags[0])
+	if tags[2] == "req" {
+		fi.required = true
+	}
+	fi.setTag(f, tag, wt)
+	fi.setMarshaler(f, tags)
+}
+
+func (fi *marshalFieldInfo) computeOneofFieldInfo(f *reflect.StructField, oneofImplementers []interface{}) {
+	fi.field = toField(f)
+	fi.wiretag = math.MaxInt32 // Use a large tag number, make oneofs sorted at the end. This tag will not appear on the wire.
+	fi.isPointer = true
+	fi.sizer, fi.marshaler = makeOneOfMarshaler(fi, f)
+	fi.oneofElems = make(map[reflect.Type]*marshalElemInfo)
+
+	ityp := f.Type // interface type
+	for _, o := range oneofImplementers {
+		t := reflect.TypeOf(o)
+		if !t.Implements(ityp) {
+			continue
+		}
+		sf := t.Elem().Field(0) // oneof implementer is a struct with a single field
+		tags := strings.Split(sf.Tag.Get("protobuf"), ",")
+		tag, err := strconv.Atoi(tags[1])
+		if err != nil {
+			panic("tag is not an integer")
+		}
+		wt := wiretype(tags[0])
+		sizer, marshaler := typeMarshaler(sf.Type, tags, false, true) // oneof should not omit any zero value
+		fi.oneofElems[t.Elem()] = &marshalElemInfo{
+			wiretag:   uint64(tag)<<3 | wt,
+			tagsize:   SizeVarint(uint64(tag) << 3),
+			sizer:     sizer,
+			marshaler: marshaler,
+		}
+	}
+}
+
+// wiretype returns the wire encoding of the type.
+func wiretype(encoding string) uint64 {
+	switch encoding {
+	case "fixed32":
+		return WireFixed32
+	case "fixed64":
+		return WireFixed64
+	case "varint", "zigzag32", "zigzag64":
+		return WireVarint
+	case "bytes":
+		return WireBytes
+	case "group":
+		return WireStartGroup
+	}
+	panic("unknown wire type " + encoding)
+}
+
+// setTag fills up the tag (in wire format) and its size in the info of a field.
+func (fi *marshalFieldInfo) setTag(f *reflect.StructField, tag int, wt uint64) {
+	fi.field = toField(f)
+	fi.wiretag = uint64(tag)<<3 | wt
+	fi.tagsize = SizeVarint(uint64(tag) << 3)
+}
+
+// setMarshaler fills up the sizer and marshaler in the info of a field.
+func (fi *marshalFieldInfo) setMarshaler(f *reflect.StructField, tags []string) {
+	switch f.Type.Kind() {
+	case reflect.Map:
+		// map field
+		fi.isPointer = true
+		fi.sizer, fi.marshaler = makeMapMarshaler(f)
+		return
+	case reflect.Ptr, reflect.Slice:
+		fi.isPointer = true
+	}
+	fi.sizer, fi.marshaler = typeMarshaler(f.Type, tags, true, false)
+}
+
+// typeMarshaler returns the sizer and marshaler of a given field.
+// t is the type of the field.
+// tags is the generated "protobuf" tag of the field.
+// If nozero is true, zero value is not marshaled to the wire.
+// If oneof is true, it is a oneof field.
+func typeMarshaler(t reflect.Type, tags []string, nozero, oneof bool) (sizer, marshaler) {
+	encoding := tags[0]
+
+	pointer := false
+	slice := false
+	if t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8 {
+		slice = true
+		t = t.Elem()
+	}
+	if t.Kind() == reflect.Ptr {
+		pointer = true
+		t = t.Elem()
+	}
+
+	packed := false
+	proto3 := false
+	validateUTF8 := true
+	for i := 2; i < len(tags); i++ {
+		if tags[i] == "packed" {
+			packed = true
+		}
+		if tags[i] == "proto3" {
+			proto3 = true
+		}
+	}
+	validateUTF8 = validateUTF8 && proto3
+
+	switch t.Kind() {
+	case reflect.Bool:
+		if pointer {
+			return sizeBoolPtr, appendBoolPtr
+		}
+		if slice {
+			if packed {
+				return sizeBoolPackedSlice, appendBoolPackedSlice
+			}
+			return sizeBoolSlice, appendBoolSlice
+		}
+		if nozero {
+			return sizeBoolValueNoZero, appendBoolValueNoZero
+		}
+		return sizeBoolValue, appendBoolValue
+	case reflect.Uint32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return sizeFixed32Ptr, appendFixed32Ptr
+			}
+			if slice {
+				if packed {
+					return sizeFixed32PackedSlice, appendFixed32PackedSlice
+				}
+				return sizeFixed32Slice, appendFixed32Slice
+			}
+			if nozero {
+				return sizeFixed32ValueNoZero, appendFixed32ValueNoZero
+			}
+			return sizeFixed32Value, appendFixed32Value
+		case "varint":
+			if pointer {
+				return sizeVarint32Ptr, appendVarint32Ptr
+			}
+			if slice {
+				if packed {
+					return sizeVarint32PackedSlice, appendVarint32PackedSlice
+				}
+				return sizeVarint32Slice, appendVarint32Slice
+			}
+			if nozero {
+				return sizeVarint32ValueNoZero, appendVarint32ValueNoZero
+			}
+			return sizeVarint32Value, appendVarint32Value
+		}
+	case reflect.Int32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return sizeFixedS32Ptr, appendFixedS32Ptr
+			}
+			if slice {
+				if packed {
+					return sizeFixedS32PackedSlice, appendFixedS32PackedSlice
+				}
+				return sizeFixedS32Slice, appendFixedS32Slice
+			}
+			if nozero {
+				return sizeFixedS32ValueNoZero, appendFixedS32ValueNoZero
+			}
+			return sizeFixedS32Value, appendFixedS32Value
+		case "varint":
+			if pointer {
+				return sizeVarintS32Ptr, appendVarintS32Ptr
+			}
+			if slice {
+				if packed {
+					return sizeVarintS32PackedSlice, appendVarintS32PackedSlice
+				}
+				return sizeVarintS32Slice, appendVarintS32Slice
+			}
+			if nozero {
+				return sizeVarintS32ValueNoZero, appendVarintS32ValueNoZero
+			}
+			return sizeVarintS32Value, appendVarintS32Value
+		case "zigzag32":
+			if pointer {
+				return sizeZigzag32Ptr, appendZigzag32Ptr
+			}
+			if slice {
+				if packed {
+					return sizeZigzag32PackedSlice, appendZigzag32PackedSlice
+				}
+				return sizeZigzag32Slice, appendZigzag32Slice
+			}
+			if nozero {
+				return sizeZigzag32ValueNoZero, appendZigzag32ValueNoZero
+			}
+			return sizeZigzag32Value, appendZigzag32Value
+		}
+	case reflect.Uint64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return sizeFixed64Ptr, appendFixed64Ptr
+			}
+			if slice {
+				if packed {
+					return sizeFixed64PackedSlice, appendFixed64PackedSlice
+				}
+				return sizeFixed64Slice, appendFixed64Slice
+			}
+			if nozero {
+				return sizeFixed64ValueNoZero, appendFixed64ValueNoZero
+			}
+			return sizeFixed64Value, appendFixed64Value
+		case "varint":
+			if pointer {
+				return sizeVarint64Ptr, appendVarint64Ptr
+			}
+			if slice {
+				if packed {
+					return sizeVarint64PackedSlice, appendVarint64PackedSlice
+				}
+				return sizeVarint64Slice, appendVarint64Slice
+			}
+			if nozero {
+				return sizeVarint64ValueNoZero, appendVarint64ValueNoZero
+			}
+			return sizeVarint64Value, appendVarint64Value
+		}
+	case reflect.Int64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return sizeFixedS64Ptr, appendFixedS64Ptr
+			}
+			if slice {
+				if packed {
+					return sizeFixedS64PackedSlice, appendFixedS64PackedSlice
+				}
+				return sizeFixedS64Slice, appendFixedS64Slice
+			}
+			if nozero {
+				return sizeFixedS64ValueNoZero, appendFixedS64ValueNoZero
+			}
+			return sizeFixedS64Value, appendFixedS64Value
+		case "varint":
+			if pointer {
+				return sizeVarintS64Ptr, appendVarintS64Ptr
+			}
+			if slice {
+				if packed {
+					return sizeVarintS64PackedSlice, appendVarintS64PackedSlice
+				}
+				return sizeVarintS64Slice, appendVarintS64Slice
+			}
+			if nozero {
+				return sizeVarintS64ValueNoZero, appendVarintS64ValueNoZero
+			}
+			return sizeVarintS64Value, appendVarintS64Value
+		case "zigzag64":
+			if pointer {
+				return sizeZigzag64Ptr, appendZigzag64Ptr
+			}
+			if slice {
+				if packed {
+					return sizeZigzag64PackedSlice, appendZigzag64PackedSlice
+				}
+				return sizeZigzag64Slice, appendZigzag64Slice
+			}
+			if nozero {
+				return sizeZigzag64ValueNoZero, appendZigzag64ValueNoZero
+			}
+			return sizeZigzag64Value, appendZigzag64Value
+		}
+	case reflect.Float32:
+		if pointer {
+			return sizeFloat32Ptr, appendFloat32Ptr
+		}
+		if slice {
+			if packed {
+				return sizeFloat32PackedSlice, appendFloat32PackedSlice
+			}
+			return sizeFloat32Slice, appendFloat32Slice
+		}
+		if nozero {
+			return sizeFloat32ValueNoZero, appendFloat32ValueNoZero
+		}
+		return sizeFloat32Value, appendFloat32Value
+	case reflect.Float64:
+		if pointer {
+			return sizeFloat64Ptr, appendFloat64Ptr
+		}
+		if slice {
+			if packed {
+				return sizeFloat64PackedSlice, appendFloat64PackedSlice
+			}
+			return sizeFloat64Slice, appendFloat64Slice
+		}
+		if nozero {
+			return sizeFloat64ValueNoZero, appendFloat64ValueNoZero
+		}
+		return sizeFloat64Value, appendFloat64Value
+	case reflect.String:
+		if validateUTF8 {
+			if pointer {
+				return sizeStringPtr, appendUTF8StringPtr
+			}
+			if slice {
+				return sizeStringSlice, appendUTF8StringSlice
+			}
+			if nozero {
+				return sizeStringValueNoZero, appendUTF8StringValueNoZero
+			}
+			return sizeStringValue, appendUTF8StringValue
+		}
+		if pointer {
+			return sizeStringPtr, appendStringPtr
+		}
+		if slice {
+			return sizeStringSlice, appendStringSlice
+		}
+		if nozero {
+			return sizeStringValueNoZero, appendStringValueNoZero
+		}
+		return sizeStringValue, appendStringValue
+	case reflect.Slice:
+		if slice {
+			return sizeBytesSlice, appendBytesSlice
+		}
+		if oneof {
+			// Oneof bytes field may also have "proto3" tag.
+			// We want to marshal it as a oneof field. Do this
+			// check before the proto3 check.
+			return sizeBytesOneof, appendBytesOneof
+		}
+		if proto3 {
+			return sizeBytes3, appendBytes3
+		}
+		return sizeBytes, appendBytes
+	case reflect.Struct:
+		switch encoding {
+		case "group":
+			if slice {
+				return makeGroupSliceMarshaler(getMarshalInfo(t))
+			}
+			return makeGroupMarshaler(getMarshalInfo(t))
+		case "bytes":
+			if slice {
+				return makeMessageSliceMarshaler(getMarshalInfo(t))
+			}
+			return makeMessageMarshaler(getMarshalInfo(t))
+		}
+	}
+	panic(fmt.Sprintf("unknown or mismatched type: type: %v, wire type: %v", t, encoding))
+}
+
+// Below are functions to size/marshal a specific type of a field.
+// They are stored in the field's info, and called by function pointers.
+// They have type sizer or marshaler.
+
+func sizeFixed32Value(_ pointer, tagsize int) int {
+	return 4 + tagsize
+}
+func sizeFixed32ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toUint32()
+	if v == 0 {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFixed32Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toUint32Ptr()
+	if p == nil {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFixed32Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint32Slice()
+	return (4 + tagsize) * len(s)
+}
+func sizeFixed32PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 4*len(s) + SizeVarint(uint64(4*len(s))) + tagsize
+}
+func sizeFixedS32Value(_ pointer, tagsize int) int {
+	return 4 + tagsize
+}
+func sizeFixedS32ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFixedS32Ptr(ptr pointer, tagsize int) int {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFixedS32Slice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	return (4 + tagsize) * len(s)
+}
+func sizeFixedS32PackedSlice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 4*len(s) + SizeVarint(uint64(4*len(s))) + tagsize
+}
+func sizeFloat32Value(_ pointer, tagsize int) int {
+	return 4 + tagsize
+}
+func sizeFloat32ValueNoZero(ptr pointer, tagsize int) int {
+	v := math.Float32bits(*ptr.toFloat32())
+	if v == 0 {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFloat32Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toFloat32Ptr()
+	if p == nil {
+		return 0
+	}
+	return 4 + tagsize
+}
+func sizeFloat32Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toFloat32Slice()
+	return (4 + tagsize) * len(s)
+}
+func sizeFloat32PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toFloat32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 4*len(s) + SizeVarint(uint64(4*len(s))) + tagsize
+}
+func sizeFixed64Value(_ pointer, tagsize int) int {
+	return 8 + tagsize
+}
+func sizeFixed64ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toUint64()
+	if v == 0 {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFixed64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toUint64Ptr()
+	if p == nil {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFixed64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint64Slice()
+	return (8 + tagsize) * len(s)
+}
+func sizeFixed64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 8*len(s) + SizeVarint(uint64(8*len(s))) + tagsize
+}
+func sizeFixedS64Value(_ pointer, tagsize int) int {
+	return 8 + tagsize
+}
+func sizeFixedS64ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFixedS64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFixedS64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	return (8 + tagsize) * len(s)
+}
+func sizeFixedS64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 8*len(s) + SizeVarint(uint64(8*len(s))) + tagsize
+}
+func sizeFloat64Value(_ pointer, tagsize int) int {
+	return 8 + tagsize
+}
+func sizeFloat64ValueNoZero(ptr pointer, tagsize int) int {
+	v := math.Float64bits(*ptr.toFloat64())
+	if v == 0 {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFloat64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toFloat64Ptr()
+	if p == nil {
+		return 0
+	}
+	return 8 + tagsize
+}
+func sizeFloat64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toFloat64Slice()
+	return (8 + tagsize) * len(s)
+}
+func sizeFloat64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toFloat64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	return 8*len(s) + SizeVarint(uint64(8*len(s))) + tagsize
+}
+func sizeVarint32Value(ptr pointer, tagsize int) int {
+	v := *ptr.toUint32()
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarint32ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toUint32()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarint32Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toUint32Ptr()
+	if p == nil {
+		return 0
+	}
+	return SizeVarint(uint64(*p)) + tagsize
+}
+func sizeVarint32Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint32Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v)) + tagsize
+	}
+	return n
+}
+func sizeVarint32PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeVarintS32Value(ptr pointer, tagsize int) int {
+	v := *ptr.toInt32()
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarintS32ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarintS32Ptr(ptr pointer, tagsize int) int {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return 0
+	}
+	return SizeVarint(uint64(*p)) + tagsize
+}
+func sizeVarintS32Slice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v)) + tagsize
+	}
+	return n
+}
+func sizeVarintS32PackedSlice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeVarint64Value(ptr pointer, tagsize int) int {
+	v := *ptr.toUint64()
+	return SizeVarint(v) + tagsize
+}
+func sizeVarint64ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toUint64()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(v) + tagsize
+}
+func sizeVarint64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toUint64Ptr()
+	if p == nil {
+		return 0
+	}
+	return SizeVarint(*p) + tagsize
+}
+func sizeVarint64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint64Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(v) + tagsize
+	}
+	return n
+}
+func sizeVarint64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toUint64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(v)
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeVarintS64Value(ptr pointer, tagsize int) int {
+	v := *ptr.toInt64()
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarintS64ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(uint64(v)) + tagsize
+}
+func sizeVarintS64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return 0
+	}
+	return SizeVarint(uint64(*p)) + tagsize
+}
+func sizeVarintS64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v)) + tagsize
+	}
+	return n
+}
+func sizeVarintS64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeZigzag32Value(ptr pointer, tagsize int) int {
+	v := *ptr.toInt32()
+	return SizeVarint(uint64((uint32(v)<<1)^uint32((int32(v)>>31)))) + tagsize
+}
+func sizeZigzag32ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(uint64((uint32(v)<<1)^uint32((int32(v)>>31)))) + tagsize
+}
+func sizeZigzag32Ptr(ptr pointer, tagsize int) int {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return 0
+	}
+	v := *p
+	return SizeVarint(uint64((uint32(v)<<1)^uint32((int32(v)>>31)))) + tagsize
+}
+func sizeZigzag32Slice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64((uint32(v)<<1)^uint32((int32(v)>>31)))) + tagsize
+	}
+	return n
+}
+func sizeZigzag32PackedSlice(ptr pointer, tagsize int) int {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64((uint32(v) << 1) ^ uint32((int32(v) >> 31))))
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeZigzag64Value(ptr pointer, tagsize int) int {
+	v := *ptr.toInt64()
+	return SizeVarint(uint64(v<<1)^uint64((int64(v)>>63))) + tagsize
+}
+func sizeZigzag64ValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return 0
+	}
+	return SizeVarint(uint64(v<<1)^uint64((int64(v)>>63))) + tagsize
+}
+func sizeZigzag64Ptr(ptr pointer, tagsize int) int {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return 0
+	}
+	v := *p
+	return SizeVarint(uint64(v<<1)^uint64((int64(v)>>63))) + tagsize
+}
+func sizeZigzag64Slice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v<<1)^uint64((int64(v)>>63))) + tagsize
+	}
+	return n
+}
+func sizeZigzag64PackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return 0
+	}
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v<<1) ^ uint64((int64(v) >> 63)))
+	}
+	return n + SizeVarint(uint64(n)) + tagsize
+}
+func sizeBoolValue(_ pointer, tagsize int) int {
+	return 1 + tagsize
+}
+func sizeBoolValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toBool()
+	if !v {
+		return 0
+	}
+	return 1 + tagsize
+}
+func sizeBoolPtr(ptr pointer, tagsize int) int {
+	p := *ptr.toBoolPtr()
+	if p == nil {
+		return 0
+	}
+	return 1 + tagsize
+}
+func sizeBoolSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toBoolSlice()
+	return (1 + tagsize) * len(s)
+}
+func sizeBoolPackedSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toBoolSlice()
+	if len(s) == 0 {
+		return 0
+	}
+	return len(s) + SizeVarint(uint64(len(s))) + tagsize
+}
+func sizeStringValue(ptr pointer, tagsize int) int {
+	v := *ptr.toString()
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeStringValueNoZero(ptr pointer, tagsize int) int {
+	v := *ptr.toString()
+	if v == "" {
+		return 0
+	}
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeStringPtr(ptr pointer, tagsize int) int {
+	p := *ptr.toStringPtr()
+	if p == nil {
+		return 0
+	}
+	v := *p
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeStringSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toStringSlice()
+	n := 0
+	for _, v := range s {
+		n += len(v) + SizeVarint(uint64(len(v))) + tagsize
+	}
+	return n
+}
+func sizeBytes(ptr pointer, tagsize int) int {
+	v := *ptr.toBytes()
+	if v == nil {
+		return 0
+	}
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeBytes3(ptr pointer, tagsize int) int {
+	v := *ptr.toBytes()
+	if len(v) == 0 {
+		return 0
+	}
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeBytesOneof(ptr pointer, tagsize int) int {
+	v := *ptr.toBytes()
+	return len(v) + SizeVarint(uint64(len(v))) + tagsize
+}
+func sizeBytesSlice(ptr pointer, tagsize int) int {
+	s := *ptr.toBytesSlice()
+	n := 0
+	for _, v := range s {
+		n += len(v) + SizeVarint(uint64(len(v))) + tagsize
+	}
+	return n
+}
+
+// appendFixed32 appends an encoded fixed32 to b.
+func appendFixed32(b []byte, v uint32) []byte {
+	b = append(b,
+		byte(v),
+		byte(v>>8),
+		byte(v>>16),
+		byte(v>>24))
+	return b
+}
+
+// appendFixed64 appends an encoded fixed64 to b.
+func appendFixed64(b []byte, v uint64) []byte {
+	b = append(b,
+		byte(v),
+		byte(v>>8),
+		byte(v>>16),
+		byte(v>>24),
+		byte(v>>32),
+		byte(v>>40),
+		byte(v>>48),
+		byte(v>>56))
+	return b
+}
+
+// appendVarint appends an encoded varint to b.
+func appendVarint(b []byte, v uint64) []byte {
+	// TODO: make 1-byte (maybe 2-byte) case inline-able, once we
+	// have non-leaf inliner.
+	switch {
+	case v < 1<<7:
+		b = append(b, byte(v))
+	case v < 1<<14:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte(v>>7))
+	case v < 1<<21:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte(v>>14))
+	case v < 1<<28:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte(v>>21))
+	case v < 1<<35:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte(v>>28))
+	case v < 1<<42:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte((v>>28)&0x7f|0x80),
+			byte(v>>35))
+	case v < 1<<49:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte((v>>28)&0x7f|0x80),
+			byte((v>>35)&0x7f|0x80),
+			byte(v>>42))
+	case v < 1<<56:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte((v>>28)&0x7f|0x80),
+			byte((v>>35)&0x7f|0x80),
+			byte((v>>42)&0x7f|0x80),
+			byte(v>>49))
+	case v < 1<<63:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte((v>>28)&0x7f|0x80),
+			byte((v>>35)&0x7f|0x80),
+			byte((v>>42)&0x7f|0x80),
+			byte((v>>49)&0x7f|0x80),
+			byte(v>>56))
+	default:
+		b = append(b,
+			byte(v&0x7f|0x80),
+			byte((v>>7)&0x7f|0x80),
+			byte((v>>14)&0x7f|0x80),
+			byte((v>>21)&0x7f|0x80),
+			byte((v>>28)&0x7f|0x80),
+			byte((v>>35)&0x7f|0x80),
+			byte((v>>42)&0x7f|0x80),
+			byte((v>>49)&0x7f|0x80),
+			byte((v>>56)&0x7f|0x80),
+			1)
+	}
+	return b
+}
+
+func appendFixed32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint32()
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, v)
+	return b, nil
+}
+func appendFixed32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint32()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, v)
+	return b, nil
+}
+func appendFixed32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toUint32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, *p)
+	return b, nil
+}
+func appendFixed32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed32(b, v)
+	}
+	return b, nil
+}
+func appendFixed32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(4*len(s)))
+	for _, v := range s {
+		b = appendFixed32(b, v)
+	}
+	return b, nil
+}
+func appendFixedS32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, uint32(v))
+	return b, nil
+}
+func appendFixedS32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, uint32(v))
+	return b, nil
+}
+func appendFixedS32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, uint32(*p))
+	return b, nil
+}
+func appendFixedS32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed32(b, uint32(v))
+	}
+	return b, nil
+}
+func appendFixedS32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(4*len(s)))
+	for _, v := range s {
+		b = appendFixed32(b, uint32(v))
+	}
+	return b, nil
+}
+func appendFloat32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := math.Float32bits(*ptr.toFloat32())
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, v)
+	return b, nil
+}
+func appendFloat32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := math.Float32bits(*ptr.toFloat32())
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, v)
+	return b, nil
+}
+func appendFloat32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toFloat32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed32(b, math.Float32bits(*p))
+	return b, nil
+}
+func appendFloat32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toFloat32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed32(b, math.Float32bits(v))
+	}
+	return b, nil
+}
+func appendFloat32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toFloat32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(4*len(s)))
+	for _, v := range s {
+		b = appendFixed32(b, math.Float32bits(v))
+	}
+	return b, nil
+}
+func appendFixed64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint64()
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, v)
+	return b, nil
+}
+func appendFixed64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint64()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, v)
+	return b, nil
+}
+func appendFixed64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toUint64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, *p)
+	return b, nil
+}
+func appendFixed64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed64(b, v)
+	}
+	return b, nil
+}
+func appendFixed64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(8*len(s)))
+	for _, v := range s {
+		b = appendFixed64(b, v)
+	}
+	return b, nil
+}
+func appendFixedS64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, uint64(v))
+	return b, nil
+}
+func appendFixedS64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, uint64(v))
+	return b, nil
+}
+func appendFixedS64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, uint64(*p))
+	return b, nil
+}
+func appendFixedS64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed64(b, uint64(v))
+	}
+	return b, nil
+}
+func appendFixedS64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(8*len(s)))
+	for _, v := range s {
+		b = appendFixed64(b, uint64(v))
+	}
+	return b, nil
+}
+func appendFloat64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := math.Float64bits(*ptr.toFloat64())
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, v)
+	return b, nil
+}
+func appendFloat64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := math.Float64bits(*ptr.toFloat64())
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, v)
+	return b, nil
+}
+func appendFloat64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toFloat64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendFixed64(b, math.Float64bits(*p))
+	return b, nil
+}
+func appendFloat64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toFloat64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendFixed64(b, math.Float64bits(v))
+	}
+	return b, nil
+}
+func appendFloat64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toFloat64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(8*len(s)))
+	for _, v := range s {
+		b = appendFixed64(b, math.Float64bits(v))
+	}
+	return b, nil
+}
+func appendVarint32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint32()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarint32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint32()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarint32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toUint32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(*p))
+	return b, nil
+}
+func appendVarint32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendVarint32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendVarintS32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarintS32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarintS32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(*p))
+	return b, nil
+}
+func appendVarintS32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendVarintS32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendVarint64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint64()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, v)
+	return b, nil
+}
+func appendVarint64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toUint64()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, v)
+	return b, nil
+}
+func appendVarint64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toUint64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, *p)
+	return b, nil
+}
+func appendVarint64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, v)
+	}
+	return b, nil
+}
+func appendVarint64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toUint64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(v)
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, v)
+	}
+	return b, nil
+}
+func appendVarintS64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarintS64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v))
+	return b, nil
+}
+func appendVarintS64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(*p))
+	return b, nil
+}
+func appendVarintS64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendVarintS64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v))
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, uint64(v))
+	}
+	return b, nil
+}
+func appendZigzag32Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64((uint32(v)<<1)^uint32((int32(v)>>31))))
+	return b, nil
+}
+func appendZigzag32ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt32()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64((uint32(v)<<1)^uint32((int32(v)>>31))))
+	return b, nil
+}
+func appendZigzag32Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := ptr.getInt32Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	v := *p
+	b = appendVarint(b, uint64((uint32(v)<<1)^uint32((int32(v)>>31))))
+	return b, nil
+}
+func appendZigzag32Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64((uint32(v)<<1)^uint32((int32(v)>>31))))
+	}
+	return b, nil
+}
+func appendZigzag32PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := ptr.getInt32Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64((uint32(v) << 1) ^ uint32((int32(v) >> 31))))
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, uint64((uint32(v)<<1)^uint32((int32(v)>>31))))
+	}
+	return b, nil
+}
+func appendZigzag64Value(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v<<1)^uint64((int64(v)>>63)))
+	return b, nil
+}
+func appendZigzag64ValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toInt64()
+	if v == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(v<<1)^uint64((int64(v)>>63)))
+	return b, nil
+}
+func appendZigzag64Ptr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toInt64Ptr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	v := *p
+	b = appendVarint(b, uint64(v<<1)^uint64((int64(v)>>63)))
+	return b, nil
+}
+func appendZigzag64Slice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(v<<1)^uint64((int64(v)>>63)))
+	}
+	return b, nil
+}
+func appendZigzag64PackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toInt64Slice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	// compute size
+	n := 0
+	for _, v := range s {
+		n += SizeVarint(uint64(v<<1) ^ uint64((int64(v) >> 63)))
+	}
+	b = appendVarint(b, uint64(n))
+	for _, v := range s {
+		b = appendVarint(b, uint64(v<<1)^uint64((int64(v)>>63)))
+	}
+	return b, nil
+}
+func appendBoolValue(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toBool()
+	b = appendVarint(b, wiretag)
+	if v {
+		b = append(b, 1)
+	} else {
+		b = append(b, 0)
+	}
+	return b, nil
+}
+func appendBoolValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toBool()
+	if !v {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = append(b, 1)
+	return b, nil
+}
+
+func appendBoolPtr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toBoolPtr()
+	if p == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	if *p {
+		b = append(b, 1)
+	} else {
+		b = append(b, 0)
+	}
+	return b, nil
+}
+func appendBoolSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toBoolSlice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		if v {
+			b = append(b, 1)
+		} else {
+			b = append(b, 0)
+		}
+	}
+	return b, nil
+}
+func appendBoolPackedSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toBoolSlice()
+	if len(s) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag&^7|WireBytes)
+	b = appendVarint(b, uint64(len(s)))
+	for _, v := range s {
+		if v {
+			b = append(b, 1)
+		} else {
+			b = append(b, 0)
+		}
+	}
+	return b, nil
+}
+func appendStringValue(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toString()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendStringValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toString()
+	if v == "" {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendStringPtr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	p := *ptr.toStringPtr()
+	if p == nil {
+		return b, nil
+	}
+	v := *p
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendStringSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toStringSlice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(len(v)))
+		b = append(b, v...)
+	}
+	return b, nil
+}
+func appendUTF8StringValue(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	var invalidUTF8 bool
+	v := *ptr.toString()
+	if !utf8.ValidString(v) {
+		invalidUTF8 = true
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	if invalidUTF8 {
+		return b, errInvalidUTF8
+	}
+	return b, nil
+}
+func appendUTF8StringValueNoZero(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	var invalidUTF8 bool
+	v := *ptr.toString()
+	if v == "" {
+		return b, nil
+	}
+	if !utf8.ValidString(v) {
+		invalidUTF8 = true
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	if invalidUTF8 {
+		return b, errInvalidUTF8
+	}
+	return b, nil
+}
+func appendUTF8StringPtr(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	var invalidUTF8 bool
+	p := *ptr.toStringPtr()
+	if p == nil {
+		return b, nil
+	}
+	v := *p
+	if !utf8.ValidString(v) {
+		invalidUTF8 = true
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	if invalidUTF8 {
+		return b, errInvalidUTF8
+	}
+	return b, nil
+}
+func appendUTF8StringSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	var invalidUTF8 bool
+	s := *ptr.toStringSlice()
+	for _, v := range s {
+		if !utf8.ValidString(v) {
+			invalidUTF8 = true
+		}
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(len(v)))
+		b = append(b, v...)
+	}
+	if invalidUTF8 {
+		return b, errInvalidUTF8
+	}
+	return b, nil
+}
+func appendBytes(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toBytes()
+	if v == nil {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendBytes3(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toBytes()
+	if len(v) == 0 {
+		return b, nil
+	}
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendBytesOneof(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	v := *ptr.toBytes()
+	b = appendVarint(b, wiretag)
+	b = appendVarint(b, uint64(len(v)))
+	b = append(b, v...)
+	return b, nil
+}
+func appendBytesSlice(b []byte, ptr pointer, wiretag uint64, _ bool) ([]byte, error) {
+	s := *ptr.toBytesSlice()
+	for _, v := range s {
+		b = appendVarint(b, wiretag)
+		b = appendVarint(b, uint64(len(v)))
+		b = append(b, v...)
+	}
+	return b, nil
+}
+
+// makeGroupMarshaler returns the sizer and marshaler for a group.
+// u is the marshal info of the underlying message.
+func makeGroupMarshaler(u *marshalInfo) (sizer, marshaler) {
+	return func(ptr pointer, tagsize int) int {
+			p := ptr.getPointer()
+			if p.isNil() {
+				return 0
+			}
+			return u.size(p) + 2*tagsize
+		},
+		func(b []byte, ptr pointer, wiretag uint64, deterministic bool) ([]byte, error) {
+			p := ptr.getPointer()
+			if p.isNil() {
+				return b, nil
+			}
+			var err error
+			b = appendVarint(b, wiretag) // start group
+			b, err = u.marshal(b, p, deterministic)
+			b = appendVarint(b, wiretag+(WireEndGroup-WireStartGroup)) // end group
+			return b, err
+		}
+}
+
+// makeGroupSliceMarshaler returns the sizer and marshaler for a group slice.
+// u is the marshal info of the underlying message.
+func makeGroupSliceMarshaler(u *marshalInfo) (sizer, marshaler) {
+	return func(ptr pointer, tagsize int) int {
+			s := ptr.getPointerSlice()
+			n := 0
+			for _, v := range s {
+				if v.isNil() {
+					continue
+				}
+				n += u.size(v) + 2*tagsize
+			}
+			return n
+		},
+		func(b []byte, ptr pointer, wiretag uint64, deterministic bool) ([]byte, error) {
+			s := ptr.getPointerSlice()
+			var err error
+			var nerr nonFatal
+			for _, v := range s {
+				if v.isNil() {
+					return b, errRepeatedHasNil
+				}
+				b = appendVarint(b, wiretag) // start group
+				b, err = u.marshal(b, v, deterministic)
+				b = appendVarint(b, wiretag+(WireEndGroup-WireStartGroup)) // end group
+				if !nerr.Merge(err) {
+					if err == ErrNil {
+						err = errRepeatedHasNil
+					}
+					return b, err
+				}
+			}
+			return b, nerr.E
+		}
+}
+
+// makeMessageMarshaler returns the sizer and marshaler for a message field.
+// u is the marshal info of the message.
+func makeMessageMarshaler(u *marshalInfo) (sizer, marshaler) {
+	return func(ptr pointer, tagsize int) int {
+			p := ptr.getPointer()
+			if p.isNil() {
+				return 0
+			}
+			siz := u.size(p)
+			return siz + SizeVarint(uint64(siz)) + tagsize
+		},
+		func(b []byte, ptr pointer, wiretag uint64, deterministic bool) ([]byte, error) {
+			p := ptr.getPointer()
+			if p.isNil() {
+				return b, nil
+			}
+			b = appendVarint(b, wiretag)
+			siz := u.cachedsize(p)
+			b = appendVarint(b, uint64(siz))
+			return u.marshal(b, p, deterministic)
+		}
+}
+
+// makeMessageSliceMarshaler returns the sizer and marshaler for a message slice.
+// u is the marshal info of the message.
+func makeMessageSliceMarshaler(u *marshalInfo) (sizer, marshaler) {
+	return func(ptr pointer, tagsize int) int {
+			s := ptr.getPointerSlice()
+			n := 0
+			for _, v := range s {
+				if v.isNil() {
+					continue
+				}
+				siz := u.size(v)
+				n += siz + SizeVarint(uint64(siz)) + tagsize
+			}
+			return n
+		},
+		func(b []byte, ptr pointer, wiretag uint64, deterministic bool) ([]byte, error) {
+			s := ptr.getPointerSlice()
+			var err error
+			var nerr nonFatal
+			for _, v := range s {
+				if v.isNil() {
+					return b, errRepeatedHasNil
+				}
+				b = appendVarint(b, wiretag)
+				siz := u.cachedsize(v)
+				b = appendVarint(b, uint64(siz))
+				b, err = u.marshal(b, v, deterministic)
+
+				if !nerr.Merge(err) {
+					if err == ErrNil {
+						err = errRepeatedHasNil
+					}
+					return b, err
+				}
+			}
+			return b, nerr.E
+		}
+}
+
+// makeMapMarshaler returns the sizer and marshaler for a map field.
+// f is the pointer to the reflect data structure of the field.
+func makeMapMarshaler(f *reflect.StructField) (sizer, marshaler) {
+	// figure out key and value type
+	t := f.Type
+	keyType := t.Key()
+	valType := t.Elem()
+	keyTags := strings.Split(f.Tag.Get("protobuf_key"), ",")
+	valTags := strings.Split(f.Tag.Get("protobuf_val"), ",")
+	keySizer, keyMarshaler := typeMarshaler(keyType, keyTags, false, false) // don't omit zero value in map
+	valSizer, valMarshaler := typeMarshaler(valType, valTags, false, false) // don't omit zero value in map
+	keyWireTag := 1<<3 | wiretype(keyTags[0])
+	valWireTag := 2<<3 | wiretype(valTags[0])
+
+	// We create an interface to get the addresses of the map key and value.
+	// If value is pointer-typed, the interface is a direct interface, the
+	// idata itself is the value. Otherwise, the idata is the pointer to the
+	// value.
+	// Key cannot be pointer-typed.
+	valIsPtr := valType.Kind() == reflect.Ptr
+
+	// If value is a message with nested maps, calling
+	// valSizer in marshal may be quadratic. We should use
+	// cached version in marshal (but not in size).
+	// If value is not message type, we don't have size cache,
+	// but it cannot be nested either. Just use valSizer.
+	valCachedSizer := valSizer
+	if valIsPtr && valType.Elem().Kind() == reflect.Struct {
+		u := getMarshalInfo(valType.Elem())
+		valCachedSizer = func(ptr pointer, tagsize int) int {
+			// Same as message sizer, but use cache.
+			p := ptr.getPointer()
+			if p.isNil() {
+				return 0
+			}
+			siz := u.cachedsize(p)
+			return siz + SizeVarint(uint64(siz)) + tagsize
+		}
+	}
+	return func(ptr pointer, tagsize int) int {
+			m := ptr.asPointerTo(t).Elem() // the map
+			n := 0
+			for _, k := range m.MapKeys() {
+				ki := k.Interface()
+				vi := m.MapIndex(k).Interface()
+				kaddr := toAddrPointer(&ki, false, false)      // pointer to key
+				vaddr := toAddrPointer(&vi, valIsPtr, false)   // pointer to value
+				siz := keySizer(kaddr, 1) + valSizer(vaddr, 1) // tag of key = 1 (size=1), tag of val = 2 (size=1)
+				n += siz + SizeVarint(uint64(siz)) + tagsize
+			}
+			return n
+		},
+		func(b []byte, ptr pointer, tag uint64, deterministic bool) ([]byte, error) {
+			m := ptr.asPointerTo(t).Elem() // the map
+			var err error
+			keys := m.MapKeys()
+			if len(keys) > 1 && deterministic {
+				sort.Sort(mapKeys(keys))
+			}
+
+			var nerr nonFatal
+			for _, k := range keys {
+				ki := k.Interface()
+				vi := m.MapIndex(k).Interface()
+				kaddr := toAddrPointer(&ki, false, false)    // pointer to key
+				vaddr := toAddrPointer(&vi, valIsPtr, false) // pointer to value
+				b = appendVarint(b, tag)
+				siz := keySizer(kaddr, 1) + valCachedSizer(vaddr, 1) // tag of key = 1 (size=1), tag of val = 2 (size=1)
+				b = appendVarint(b, uint64(siz))
+				b, err = keyMarshaler(b, kaddr, keyWireTag, deterministic)
+				if !nerr.Merge(err) {
+					return b, err
+				}
+				b, err = valMarshaler(b, vaddr, valWireTag, deterministic)
+				if err != ErrNil && !nerr.Merge(err) { // allow nil value in map
+					return b, err
+				}
+			}
+			return b, nerr.E
+		}
+}
+
+// makeOneOfMarshaler returns the sizer and marshaler for a oneof field.
+// fi is the marshal info of the field.
+// f is the pointer to the reflect data structure of the field.
+func makeOneOfMarshaler(fi *marshalFieldInfo, f *reflect.StructField) (sizer, marshaler) {
+	// Oneof field is an interface. We need to get the actual data type on the fly.
+	t := f.Type
+	return func(ptr pointer, _ int) int {
+			p := ptr.getInterfacePointer()
+			if p.isNil() {
+				return 0
+			}
+			v := ptr.asPointerTo(t).Elem().Elem().Elem() // *interface -> interface -> *struct -> struct
+			telem := v.Type()
+			e := fi.oneofElems[telem]
+			return e.sizer(p, e.tagsize)
+		},
+		func(b []byte, ptr pointer, _ uint64, deterministic bool) ([]byte, error) {
+			p := ptr.getInterfacePointer()
+			if p.isNil() {
+				return b, nil
+			}
+			v := ptr.asPointerTo(t).Elem().Elem().Elem() // *interface -> interface -> *struct -> struct
+			telem := v.Type()
+			if telem.Field(0).Type.Kind() == reflect.Ptr && p.getPointer().isNil() {
+				return b, errOneofHasNil
+			}
+			e := fi.oneofElems[telem]
+			return e.marshaler(b, p, e.wiretag, deterministic)
+		}
+}
+
+// sizeExtensions computes the size of encoded data for a XXX_InternalExtensions field.
+func (u *marshalInfo) sizeExtensions(ext *XXX_InternalExtensions) int {
+	m, mu := ext.extensionsRead()
+	if m == nil {
+		return 0
+	}
+	mu.Lock()
+
+	n := 0
+	for _, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			n += len(e.enc)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		n += ei.sizer(p, ei.tagsize)
+	}
+	mu.Unlock()
+	return n
+}
+
+// appendExtensions marshals a XXX_InternalExtensions field to the end of byte slice b.
+func (u *marshalInfo) appendExtensions(b []byte, ext *XXX_InternalExtensions, deterministic bool) ([]byte, error) {
+	m, mu := ext.extensionsRead()
+	if m == nil {
+		return b, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+
+	var err error
+	var nerr nonFatal
+
+	// Fast-path for common cases: zero or one extensions.
+	// Don't bother sorting the keys.
+	if len(m) <= 1 {
+		for _, e := range m {
+			if e.value == nil || e.desc == nil {
+				// Extension is only in its encoded form.
+				b = append(b, e.enc...)
+				continue
+			}
+
+			// We don't skip extensions that have an encoded form set,
+			// because the extension value may have been mutated after
+			// the last time this function was called.
+
+			ei := u.getExtElemInfo(e.desc)
+			v := e.value
+			p := toAddrPointer(&v, ei.isptr, ei.deref)
+			b, err = ei.marshaler(b, p, ei.wiretag, deterministic)
+			if !nerr.Merge(err) {
+				return b, err
+			}
+		}
+		return b, nerr.E
+	}
+
+	// Sort the keys to provide a deterministic encoding.
+	// Not sure this is required, but the old code does it.
+	keys := make([]int, 0, len(m))
+	for k := range m {
+		keys = append(keys, int(k))
+	}
+	sort.Ints(keys)
+
+	for _, k := range keys {
+		e := m[int32(k)]
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			b = append(b, e.enc...)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		b, err = ei.marshaler(b, p, ei.wiretag, deterministic)
+		if !nerr.Merge(err) {
+			return b, err
+		}
+	}
+	return b, nerr.E
+}
+
+// message set format is:
+//   message MessageSet {
+//     repeated group Item = 1 {
+//       required int32 type_id = 2;
+//       required string message = 3;
+//     };
+//   }
+
+// sizeMessageSet computes the size of encoded data for a XXX_InternalExtensions field
+// in message set format (above).
+func (u *marshalInfo) sizeMessageSet(ext *XXX_InternalExtensions) int {
+	m, mu := ext.extensionsRead()
+	if m == nil {
+		return 0
+	}
+	mu.Lock()
+
+	n := 0
+	for id, e := range m {
+		n += 2                          // start group, end group. tag = 1 (size=1)
+		n += SizeVarint(uint64(id)) + 1 // type_id, tag = 2 (size=1)
+
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			msgWithLen := skipVarint(e.enc) // skip old tag, but leave the length varint
+			siz := len(msgWithLen)
+			n += siz + 1 // message, tag = 3 (size=1)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		n += ei.sizer(p, 1) // message, tag = 3 (size=1)
+	}
+	mu.Unlock()
+	return n
+}
+
+// appendMessageSet marshals a XXX_InternalExtensions field in message set format (above)
+// to the end of byte slice b.
+func (u *marshalInfo) appendMessageSet(b []byte, ext *XXX_InternalExtensions, deterministic bool) ([]byte, error) {
+	m, mu := ext.extensionsRead()
+	if m == nil {
+		return b, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+
+	var err error
+	var nerr nonFatal
+
+	// Fast-path for common cases: zero or one extensions.
+	// Don't bother sorting the keys.
+	if len(m) <= 1 {
+		for id, e := range m {
+			b = append(b, 1<<3|WireStartGroup)
+			b = append(b, 2<<3|WireVarint)
+			b = appendVarint(b, uint64(id))
+
+			if e.value == nil || e.desc == nil {
+				// Extension is only in its encoded form.
+				msgWithLen := skipVarint(e.enc) // skip old tag, but leave the length varint
+				b = append(b, 3<<3|WireBytes)
+				b = append(b, msgWithLen...)
+				b = append(b, 1<<3|WireEndGroup)
+				continue
+			}
+
+			// We don't skip extensions that have an encoded form set,
+			// because the extension value may have been mutated after
+			// the last time this function was called.
+
+			ei := u.getExtElemInfo(e.desc)
+			v := e.value
+			p := toAddrPointer(&v, ei.isptr, ei.deref)
+			b, err = ei.marshaler(b, p, 3<<3|WireBytes, deterministic)
+			if !nerr.Merge(err) {
+				return b, err
+			}
+			b = append(b, 1<<3|WireEndGroup)
+		}
+		return b, nerr.E
+	}
+
+	// Sort the keys to provide a deterministic encoding.
+	keys := make([]int, 0, len(m))
+	for k := range m {
+		keys = append(keys, int(k))
+	}
+	sort.Ints(keys)
+
+	for _, id := range keys {
+		e := m[int32(id)]
+		b = append(b, 1<<3|WireStartGroup)
+		b = append(b, 2<<3|WireVarint)
+		b = appendVarint(b, uint64(id))
+
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			msgWithLen := skipVarint(e.enc) // skip old tag, but leave the length varint
+			b = append(b, 3<<3|WireBytes)
+			b = append(b, msgWithLen...)
+			b = append(b, 1<<3|WireEndGroup)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		b, err = ei.marshaler(b, p, 3<<3|WireBytes, deterministic)
+		b = append(b, 1<<3|WireEndGroup)
+		if !nerr.Merge(err) {
+			return b, err
+		}
+	}
+	return b, nerr.E
+}
+
+// sizeV1Extensions computes the size of encoded data for a V1-API extension field.
+func (u *marshalInfo) sizeV1Extensions(m map[int32]Extension) int {
+	if m == nil {
+		return 0
+	}
+
+	n := 0
+	for _, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			n += len(e.enc)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		n += ei.sizer(p, ei.tagsize)
+	}
+	return n
+}
+
+// appendV1Extensions marshals a V1-API extension field to the end of byte slice b.
+func (u *marshalInfo) appendV1Extensions(b []byte, m map[int32]Extension, deterministic bool) ([]byte, error) {
+	if m == nil {
+		return b, nil
+	}
+
+	// Sort the keys to provide a deterministic encoding.
+	keys := make([]int, 0, len(m))
+	for k := range m {
+		keys = append(keys, int(k))
+	}
+	sort.Ints(keys)
+
+	var err error
+	var nerr nonFatal
+	for _, k := range keys {
+		e := m[int32(k)]
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			b = append(b, e.enc...)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		ei := u.getExtElemInfo(e.desc)
+		v := e.value
+		p := toAddrPointer(&v, ei.isptr, ei.deref)
+		b, err = ei.marshaler(b, p, ei.wiretag, deterministic)
+		if !nerr.Merge(err) {
+			return b, err
+		}
+	}
+	return b, nerr.E
+}
+
+// newMarshaler is the interface representing objects that can marshal themselves.
+//
+// This exists to support protoc-gen-go generated messages.
+// The proto package will stop type-asserting to this interface in the future.
+//
+// DO NOT DEPEND ON THIS.
+type newMarshaler interface {
+	XXX_Size() int
+	XXX_Marshal(b []byte, deterministic bool) ([]byte, error)
+}
+
+// Size returns the encoded size of a protocol buffer message.
+// This is the main entry point.
+func Size(pb Message) int {
+	if m, ok := pb.(newMarshaler); ok {
+		return m.XXX_Size()
+	}
+	if m, ok := pb.(Marshaler); ok {
+		// If the message can marshal itself, let it do it, for compatibility.
+		// NOTE: This is not efficient.
+		b, _ := m.Marshal()
+		return len(b)
+	}
+	// in case somehow we didn't generate the wrapper
+	if pb == nil {
+		return 0
+	}
+	var info InternalMessageInfo
+	return info.Size(pb)
+}
+
+// Marshal takes a protocol buffer message
+// and encodes it into the wire format, returning the data.
+// This is the main entry point.
+func Marshal(pb Message) ([]byte, error) {
+	if m, ok := pb.(newMarshaler); ok {
+		siz := m.XXX_Size()
+		b := make([]byte, 0, siz)
+		return m.XXX_Marshal(b, false)
+	}
+	if m, ok := pb.(Marshaler); ok {
+		// If the message can marshal itself, let it do it, for compatibility.
+		// NOTE: This is not efficient.
+		return m.Marshal()
+	}
+	// in case somehow we didn't generate the wrapper
+	if pb == nil {
+		return nil, ErrNil
+	}
+	var info InternalMessageInfo
+	siz := info.Size(pb)
+	b := make([]byte, 0, siz)
+	return info.Marshal(b, pb, false)
+}
+
+// Marshal takes a protocol buffer message
+// and encodes it into the wire format, writing the result to the
+// Buffer.
+// This is an alternative entry point. It is not necessary to use
+// a Buffer for most applications.
+func (p *Buffer) Marshal(pb Message) error {
+	var err error
+	if m, ok := pb.(newMarshaler); ok {
+		siz := m.XXX_Size()
+		p.grow(siz) // make sure buf has enough capacity
+		p.buf, err = m.XXX_Marshal(p.buf, p.deterministic)
+		return err
+	}
+	if m, ok := pb.(Marshaler); ok {
+		// If the message can marshal itself, let it do it, for compatibility.
+		// NOTE: This is not efficient.
+		b, err := m.Marshal()
+		p.buf = append(p.buf, b...)
+		return err
+	}
+	// in case somehow we didn't generate the wrapper
+	if pb == nil {
+		return ErrNil
+	}
+	var info InternalMessageInfo
+	siz := info.Size(pb)
+	p.grow(siz) // make sure buf has enough capacity
+	p.buf, err = info.Marshal(p.buf, pb, p.deterministic)
+	return err
+}
+
+// grow grows the buffer's capacity, if necessary, to guarantee space for
+// another n bytes. After grow(n), at least n bytes can be written to the
+// buffer without another allocation.
+func (p *Buffer) grow(n int) {
+	need := len(p.buf) + n
+	if need <= cap(p.buf) {
+		return
+	}
+	newCap := len(p.buf) * 2
+	if newCap < need {
+		newCap = need
+	}
+	p.buf = append(make([]byte, 0, newCap), p.buf...)
+}
diff --git a/vendor/github.com/golang/protobuf/proto/table_merge.go b/vendor/github.com/golang/protobuf/proto/table_merge.go
new file mode 100644
index 0000000000..5525def6a5
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/table_merge.go
@@ -0,0 +1,654 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2016 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+)
+
+// Merge merges the src message into dst.
+// This assumes that dst and src of the same type and are non-nil.
+func (a *InternalMessageInfo) Merge(dst, src Message) {
+	mi := atomicLoadMergeInfo(&a.merge)
+	if mi == nil {
+		mi = getMergeInfo(reflect.TypeOf(dst).Elem())
+		atomicStoreMergeInfo(&a.merge, mi)
+	}
+	mi.merge(toPointer(&dst), toPointer(&src))
+}
+
+type mergeInfo struct {
+	typ reflect.Type
+
+	initialized int32 // 0: only typ is valid, 1: everything is valid
+	lock        sync.Mutex
+
+	fields       []mergeFieldInfo
+	unrecognized field // Offset of XXX_unrecognized
+}
+
+type mergeFieldInfo struct {
+	field field // Offset of field, guaranteed to be valid
+
+	// isPointer reports whether the value in the field is a pointer.
+	// This is true for the following situations:
+	//	* Pointer to struct
+	//	* Pointer to basic type (proto2 only)
+	//	* Slice (first value in slice header is a pointer)
+	//	* String (first value in string header is a pointer)
+	isPointer bool
+
+	// basicWidth reports the width of the field assuming that it is directly
+	// embedded in the struct (as is the case for basic types in proto3).
+	// The possible values are:
+	// 	0: invalid
+	//	1: bool
+	//	4: int32, uint32, float32
+	//	8: int64, uint64, float64
+	basicWidth int
+
+	// Where dst and src are pointers to the types being merged.
+	merge func(dst, src pointer)
+}
+
+var (
+	mergeInfoMap  = map[reflect.Type]*mergeInfo{}
+	mergeInfoLock sync.Mutex
+)
+
+func getMergeInfo(t reflect.Type) *mergeInfo {
+	mergeInfoLock.Lock()
+	defer mergeInfoLock.Unlock()
+	mi := mergeInfoMap[t]
+	if mi == nil {
+		mi = &mergeInfo{typ: t}
+		mergeInfoMap[t] = mi
+	}
+	return mi
+}
+
+// merge merges src into dst assuming they are both of type *mi.typ.
+func (mi *mergeInfo) merge(dst, src pointer) {
+	if dst.isNil() {
+		panic("proto: nil destination")
+	}
+	if src.isNil() {
+		return // Nothing to do.
+	}
+
+	if atomic.LoadInt32(&mi.initialized) == 0 {
+		mi.computeMergeInfo()
+	}
+
+	for _, fi := range mi.fields {
+		sfp := src.offset(fi.field)
+
+		// As an optimization, we can avoid the merge function call cost
+		// if we know for sure that the source will have no effect
+		// by checking if it is the zero value.
+		if unsafeAllowed {
+			if fi.isPointer && sfp.getPointer().isNil() { // Could be slice or string
+				continue
+			}
+			if fi.basicWidth > 0 {
+				switch {
+				case fi.basicWidth == 1 && !*sfp.toBool():
+					continue
+				case fi.basicWidth == 4 && *sfp.toUint32() == 0:
+					continue
+				case fi.basicWidth == 8 && *sfp.toUint64() == 0:
+					continue
+				}
+			}
+		}
+
+		dfp := dst.offset(fi.field)
+		fi.merge(dfp, sfp)
+	}
+
+	// TODO: Make this faster?
+	out := dst.asPointerTo(mi.typ).Elem()
+	in := src.asPointerTo(mi.typ).Elem()
+	if emIn, err := extendable(in.Addr().Interface()); err == nil {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
+	}
+
+	if mi.unrecognized.IsValid() {
+		if b := *src.offset(mi.unrecognized).toBytes(); len(b) > 0 {
+			*dst.offset(mi.unrecognized).toBytes() = append([]byte(nil), b...)
+		}
+	}
+}
+
+func (mi *mergeInfo) computeMergeInfo() {
+	mi.lock.Lock()
+	defer mi.lock.Unlock()
+	if mi.initialized != 0 {
+		return
+	}
+	t := mi.typ
+	n := t.NumField()
+
+	props := GetProperties(t)
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+
+		mfi := mergeFieldInfo{field: toField(&f)}
+		tf := f.Type
+
+		// As an optimization, we can avoid the merge function call cost
+		// if we know for sure that the source will have no effect
+		// by checking if it is the zero value.
+		if unsafeAllowed {
+			switch tf.Kind() {
+			case reflect.Ptr, reflect.Slice, reflect.String:
+				// As a special case, we assume slices and strings are pointers
+				// since we know that the first field in the SliceSlice or
+				// StringHeader is a data pointer.
+				mfi.isPointer = true
+			case reflect.Bool:
+				mfi.basicWidth = 1
+			case reflect.Int32, reflect.Uint32, reflect.Float32:
+				mfi.basicWidth = 4
+			case reflect.Int64, reflect.Uint64, reflect.Float64:
+				mfi.basicWidth = 8
+			}
+		}
+
+		// Unwrap tf to get at its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic("both pointer and slice for basic type in " + tf.Name())
+		}
+
+		switch tf.Kind() {
+		case reflect.Int32:
+			switch {
+			case isSlice: // E.g., []int32
+				mfi.merge = func(dst, src pointer) {
+					// NOTE: toInt32Slice is not defined (see pointer_reflect.go).
+					/*
+						sfsp := src.toInt32Slice()
+						if *sfsp != nil {
+							dfsp := dst.toInt32Slice()
+							*dfsp = append(*dfsp, *sfsp...)
+							if *dfsp == nil {
+								*dfsp = []int64{}
+							}
+						}
+					*/
+					sfs := src.getInt32Slice()
+					if sfs != nil {
+						dfs := dst.getInt32Slice()
+						dfs = append(dfs, sfs...)
+						if dfs == nil {
+							dfs = []int32{}
+						}
+						dst.setInt32Slice(dfs)
+					}
+				}
+			case isPointer: // E.g., *int32
+				mfi.merge = func(dst, src pointer) {
+					// NOTE: toInt32Ptr is not defined (see pointer_reflect.go).
+					/*
+						sfpp := src.toInt32Ptr()
+						if *sfpp != nil {
+							dfpp := dst.toInt32Ptr()
+							if *dfpp == nil {
+								*dfpp = Int32(**sfpp)
+							} else {
+								**dfpp = **sfpp
+							}
+						}
+					*/
+					sfp := src.getInt32Ptr()
+					if sfp != nil {
+						dfp := dst.getInt32Ptr()
+						if dfp == nil {
+							dst.setInt32Ptr(*sfp)
+						} else {
+							*dfp = *sfp
+						}
+					}
+				}
+			default: // E.g., int32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toInt32(); v != 0 {
+						*dst.toInt32() = v
+					}
+				}
+			}
+		case reflect.Int64:
+			switch {
+			case isSlice: // E.g., []int64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toInt64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toInt64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []int64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *int64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toInt64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toInt64Ptr()
+						if *dfpp == nil {
+							*dfpp = Int64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., int64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toInt64(); v != 0 {
+						*dst.toInt64() = v
+					}
+				}
+			}
+		case reflect.Uint32:
+			switch {
+			case isSlice: // E.g., []uint32
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toUint32Slice()
+					if *sfsp != nil {
+						dfsp := dst.toUint32Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []uint32{}
+						}
+					}
+				}
+			case isPointer: // E.g., *uint32
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toUint32Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toUint32Ptr()
+						if *dfpp == nil {
+							*dfpp = Uint32(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., uint32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toUint32(); v != 0 {
+						*dst.toUint32() = v
+					}
+				}
+			}
+		case reflect.Uint64:
+			switch {
+			case isSlice: // E.g., []uint64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toUint64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toUint64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []uint64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *uint64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toUint64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toUint64Ptr()
+						if *dfpp == nil {
+							*dfpp = Uint64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., uint64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toUint64(); v != 0 {
+						*dst.toUint64() = v
+					}
+				}
+			}
+		case reflect.Float32:
+			switch {
+			case isSlice: // E.g., []float32
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toFloat32Slice()
+					if *sfsp != nil {
+						dfsp := dst.toFloat32Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []float32{}
+						}
+					}
+				}
+			case isPointer: // E.g., *float32
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toFloat32Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toFloat32Ptr()
+						if *dfpp == nil {
+							*dfpp = Float32(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., float32
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toFloat32(); v != 0 {
+						*dst.toFloat32() = v
+					}
+				}
+			}
+		case reflect.Float64:
+			switch {
+			case isSlice: // E.g., []float64
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toFloat64Slice()
+					if *sfsp != nil {
+						dfsp := dst.toFloat64Slice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []float64{}
+						}
+					}
+				}
+			case isPointer: // E.g., *float64
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toFloat64Ptr()
+					if *sfpp != nil {
+						dfpp := dst.toFloat64Ptr()
+						if *dfpp == nil {
+							*dfpp = Float64(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., float64
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toFloat64(); v != 0 {
+						*dst.toFloat64() = v
+					}
+				}
+			}
+		case reflect.Bool:
+			switch {
+			case isSlice: // E.g., []bool
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toBoolSlice()
+					if *sfsp != nil {
+						dfsp := dst.toBoolSlice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []bool{}
+						}
+					}
+				}
+			case isPointer: // E.g., *bool
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toBoolPtr()
+					if *sfpp != nil {
+						dfpp := dst.toBoolPtr()
+						if *dfpp == nil {
+							*dfpp = Bool(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., bool
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toBool(); v {
+						*dst.toBool() = v
+					}
+				}
+			}
+		case reflect.String:
+			switch {
+			case isSlice: // E.g., []string
+				mfi.merge = func(dst, src pointer) {
+					sfsp := src.toStringSlice()
+					if *sfsp != nil {
+						dfsp := dst.toStringSlice()
+						*dfsp = append(*dfsp, *sfsp...)
+						if *dfsp == nil {
+							*dfsp = []string{}
+						}
+					}
+				}
+			case isPointer: // E.g., *string
+				mfi.merge = func(dst, src pointer) {
+					sfpp := src.toStringPtr()
+					if *sfpp != nil {
+						dfpp := dst.toStringPtr()
+						if *dfpp == nil {
+							*dfpp = String(**sfpp)
+						} else {
+							**dfpp = **sfpp
+						}
+					}
+				}
+			default: // E.g., string
+				mfi.merge = func(dst, src pointer) {
+					if v := *src.toString(); v != "" {
+						*dst.toString() = v
+					}
+				}
+			}
+		case reflect.Slice:
+			isProto3 := props.Prop[i].proto3
+			switch {
+			case isPointer:
+				panic("bad pointer in byte slice case in " + tf.Name())
+			case tf.Elem().Kind() != reflect.Uint8:
+				panic("bad element kind in byte slice case in " + tf.Name())
+			case isSlice: // E.g., [][]byte
+				mfi.merge = func(dst, src pointer) {
+					sbsp := src.toBytesSlice()
+					if *sbsp != nil {
+						dbsp := dst.toBytesSlice()
+						for _, sb := range *sbsp {
+							if sb == nil {
+								*dbsp = append(*dbsp, nil)
+							} else {
+								*dbsp = append(*dbsp, append([]byte{}, sb...))
+							}
+						}
+						if *dbsp == nil {
+							*dbsp = [][]byte{}
+						}
+					}
+				}
+			default: // E.g., []byte
+				mfi.merge = func(dst, src pointer) {
+					sbp := src.toBytes()
+					if *sbp != nil {
+						dbp := dst.toBytes()
+						if !isProto3 || len(*sbp) > 0 {
+							*dbp = append([]byte{}, *sbp...)
+						}
+					}
+				}
+			}
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("message field %s without pointer", tf))
+			case isSlice: // E.g., []*pb.T
+				mi := getMergeInfo(tf)
+				mfi.merge = func(dst, src pointer) {
+					sps := src.getPointerSlice()
+					if sps != nil {
+						dps := dst.getPointerSlice()
+						for _, sp := range sps {
+							var dp pointer
+							if !sp.isNil() {
+								dp = valToPointer(reflect.New(tf))
+								mi.merge(dp, sp)
+							}
+							dps = append(dps, dp)
+						}
+						if dps == nil {
+							dps = []pointer{}
+						}
+						dst.setPointerSlice(dps)
+					}
+				}
+			default: // E.g., *pb.T
+				mi := getMergeInfo(tf)
+				mfi.merge = func(dst, src pointer) {
+					sp := src.getPointer()
+					if !sp.isNil() {
+						dp := dst.getPointer()
+						if dp.isNil() {
+							dp = valToPointer(reflect.New(tf))
+							dst.setPointer(dp)
+						}
+						mi.merge(dp, sp)
+					}
+				}
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic("bad pointer or slice in map case in " + tf.Name())
+			default: // E.g., map[K]V
+				mfi.merge = func(dst, src pointer) {
+					sm := src.asPointerTo(tf).Elem()
+					if sm.Len() == 0 {
+						return
+					}
+					dm := dst.asPointerTo(tf).Elem()
+					if dm.IsNil() {
+						dm.Set(reflect.MakeMap(tf))
+					}
+
+					switch tf.Elem().Kind() {
+					case reflect.Ptr: // Proto struct (e.g., *T)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							val = reflect.ValueOf(Clone(val.Interface().(Message)))
+							dm.SetMapIndex(key, val)
+						}
+					case reflect.Slice: // E.g. Bytes type (e.g., []byte)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+							dm.SetMapIndex(key, val)
+						}
+					default: // Basic type (e.g., string)
+						for _, key := range sm.MapKeys() {
+							val := sm.MapIndex(key)
+							dm.SetMapIndex(key, val)
+						}
+					}
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic("bad pointer or slice in interface case in " + tf.Name())
+			default: // E.g., interface{}
+				// TODO: Make this faster?
+				mfi.merge = func(dst, src pointer) {
+					su := src.asPointerTo(tf).Elem()
+					if !su.IsNil() {
+						du := dst.asPointerTo(tf).Elem()
+						typ := su.Elem().Type()
+						if du.IsNil() || du.Elem().Type() != typ {
+							du.Set(reflect.New(typ.Elem())) // Initialize interface if empty
+						}
+						sv := su.Elem().Elem().Field(0)
+						if sv.Kind() == reflect.Ptr && sv.IsNil() {
+							return
+						}
+						dv := du.Elem().Elem().Field(0)
+						if dv.Kind() == reflect.Ptr && dv.IsNil() {
+							dv.Set(reflect.New(sv.Type().Elem())) // Initialize proto message if empty
+						}
+						switch sv.Type().Kind() {
+						case reflect.Ptr: // Proto struct (e.g., *T)
+							Merge(dv.Interface().(Message), sv.Interface().(Message))
+						case reflect.Slice: // E.g. Bytes type (e.g., []byte)
+							dv.Set(reflect.ValueOf(append([]byte{}, sv.Bytes()...)))
+						default: // Basic type (e.g., string)
+							dv.Set(sv)
+						}
+					}
+				}
+			}
+		default:
+			panic(fmt.Sprintf("merger not found for type:%s", tf))
+		}
+		mi.fields = append(mi.fields, mfi)
+	}
+
+	mi.unrecognized = invalidField
+	if f, ok := t.FieldByName("XXX_unrecognized"); ok {
+		if f.Type != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		mi.unrecognized = toField(&f)
+	}
+
+	atomic.StoreInt32(&mi.initialized, 1)
+}
diff --git a/vendor/github.com/golang/protobuf/proto/table_unmarshal.go b/vendor/github.com/golang/protobuf/proto/table_unmarshal.go
new file mode 100644
index 0000000000..acee2fc529
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/table_unmarshal.go
@@ -0,0 +1,2053 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2016 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"unicode/utf8"
+)
+
+// Unmarshal is the entry point from the generated .pb.go files.
+// This function is not intended to be used by non-generated code.
+// This function is not subject to any compatibility guarantee.
+// msg contains a pointer to a protocol buffer struct.
+// b is the data to be unmarshaled into the protocol buffer.
+// a is a pointer to a place to store cached unmarshal information.
+func (a *InternalMessageInfo) Unmarshal(msg Message, b []byte) error {
+	// Load the unmarshal information for this message type.
+	// The atomic load ensures memory consistency.
+	u := atomicLoadUnmarshalInfo(&a.unmarshal)
+	if u == nil {
+		// Slow path: find unmarshal info for msg, update a with it.
+		u = getUnmarshalInfo(reflect.TypeOf(msg).Elem())
+		atomicStoreUnmarshalInfo(&a.unmarshal, u)
+	}
+	// Then do the unmarshaling.
+	err := u.unmarshal(toPointer(&msg), b)
+	return err
+}
+
+type unmarshalInfo struct {
+	typ reflect.Type // type of the protobuf struct
+
+	// 0 = only typ field is initialized
+	// 1 = completely initialized
+	initialized     int32
+	lock            sync.Mutex                    // prevents double initialization
+	dense           []unmarshalFieldInfo          // fields indexed by tag #
+	sparse          map[uint64]unmarshalFieldInfo // fields indexed by tag #
+	reqFields       []string                      // names of required fields
+	reqMask         uint64                        // 1<<len(reqFields)-1
+	unrecognized    field                         // offset of []byte to put unrecognized data (or invalidField if we should throw it away)
+	extensions      field                         // offset of extensions field (of type proto.XXX_InternalExtensions), or invalidField if it does not exist
+	oldExtensions   field                         // offset of old-form extensions field (of type map[int]Extension)
+	extensionRanges []ExtensionRange              // if non-nil, implies extensions field is valid
+	isMessageSet    bool                          // if true, implies extensions field is valid
+}
+
+// An unmarshaler takes a stream of bytes and a pointer to a field of a message.
+// It decodes the field, stores it at f, and returns the unused bytes.
+// w is the wire encoding.
+// b is the data after the tag and wire encoding have been read.
+type unmarshaler func(b []byte, f pointer, w int) ([]byte, error)
+
+type unmarshalFieldInfo struct {
+	// location of the field in the proto message structure.
+	field field
+
+	// function to unmarshal the data for the field.
+	unmarshal unmarshaler
+
+	// if a required field, contains a single set bit at this field's index in the required field list.
+	reqMask uint64
+
+	name string // name of the field, for error reporting
+}
+
+var (
+	unmarshalInfoMap  = map[reflect.Type]*unmarshalInfo{}
+	unmarshalInfoLock sync.Mutex
+)
+
+// getUnmarshalInfo returns the data structure which can be
+// subsequently used to unmarshal a message of the given type.
+// t is the type of the message (note: not pointer to message).
+func getUnmarshalInfo(t reflect.Type) *unmarshalInfo {
+	// It would be correct to return a new unmarshalInfo
+	// unconditionally. We would end up allocating one
+	// per occurrence of that type as a message or submessage.
+	// We use a cache here just to reduce memory usage.
+	unmarshalInfoLock.Lock()
+	defer unmarshalInfoLock.Unlock()
+	u := unmarshalInfoMap[t]
+	if u == nil {
+		u = &unmarshalInfo{typ: t}
+		// Note: we just set the type here. The rest of the fields
+		// will be initialized on first use.
+		unmarshalInfoMap[t] = u
+	}
+	return u
+}
+
+// unmarshal does the main work of unmarshaling a message.
+// u provides type information used to unmarshal the message.
+// m is a pointer to a protocol buffer message.
+// b is a byte stream to unmarshal into m.
+// This is top routine used when recursively unmarshaling submessages.
+func (u *unmarshalInfo) unmarshal(m pointer, b []byte) error {
+	if atomic.LoadInt32(&u.initialized) == 0 {
+		u.computeUnmarshalInfo()
+	}
+	if u.isMessageSet {
+		return unmarshalMessageSet(b, m.offset(u.extensions).toExtensions())
+	}
+	var reqMask uint64 // bitmask of required fields we've seen.
+	var errLater error
+	for len(b) > 0 {
+		// Read tag and wire type.
+		// Special case 1 and 2 byte varints.
+		var x uint64
+		if b[0] < 128 {
+			x = uint64(b[0])
+			b = b[1:]
+		} else if len(b) >= 2 && b[1] < 128 {
+			x = uint64(b[0]&0x7f) + uint64(b[1])<<7
+			b = b[2:]
+		} else {
+			var n int
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+		}
+		tag := x >> 3
+		wire := int(x) & 7
+
+		// Dispatch on the tag to one of the unmarshal* functions below.
+		var f unmarshalFieldInfo
+		if tag < uint64(len(u.dense)) {
+			f = u.dense[tag]
+		} else {
+			f = u.sparse[tag]
+		}
+		if fn := f.unmarshal; fn != nil {
+			var err error
+			b, err = fn(b, m.offset(f.field), wire)
+			if err == nil {
+				reqMask |= f.reqMask
+				continue
+			}
+			if r, ok := err.(*RequiredNotSetError); ok {
+				// Remember this error, but keep parsing. We need to produce
+				// a full parse even if a required field is missing.
+				if errLater == nil {
+					errLater = r
+				}
+				reqMask |= f.reqMask
+				continue
+			}
+			if err != errInternalBadWireType {
+				if err == errInvalidUTF8 {
+					if errLater == nil {
+						fullName := revProtoTypes[reflect.PtrTo(u.typ)] + "." + f.name
+						errLater = &invalidUTF8Error{fullName}
+					}
+					continue
+				}
+				return err
+			}
+			// Fragments with bad wire type are treated as unknown fields.
+		}
+
+		// Unknown tag.
+		if !u.unrecognized.IsValid() {
+			// Don't keep unrecognized data; just skip it.
+			var err error
+			b, err = skipField(b, wire)
+			if err != nil {
+				return err
+			}
+			continue
+		}
+		// Keep unrecognized data around.
+		// maybe in extensions, maybe in the unrecognized field.
+		z := m.offset(u.unrecognized).toBytes()
+		var emap map[int32]Extension
+		var e Extension
+		for _, r := range u.extensionRanges {
+			if uint64(r.Start) <= tag && tag <= uint64(r.End) {
+				if u.extensions.IsValid() {
+					mp := m.offset(u.extensions).toExtensions()
+					emap = mp.extensionsWrite()
+					e = emap[int32(tag)]
+					z = &e.enc
+					break
+				}
+				if u.oldExtensions.IsValid() {
+					p := m.offset(u.oldExtensions).toOldExtensions()
+					emap = *p
+					if emap == nil {
+						emap = map[int32]Extension{}
+						*p = emap
+					}
+					e = emap[int32(tag)]
+					z = &e.enc
+					break
+				}
+				panic("no extensions field available")
+			}
+		}
+
+		// Use wire type to skip data.
+		var err error
+		b0 := b
+		b, err = skipField(b, wire)
+		if err != nil {
+			return err
+		}
+		*z = encodeVarint(*z, tag<<3|uint64(wire))
+		*z = append(*z, b0[:len(b0)-len(b)]...)
+
+		if emap != nil {
+			emap[int32(tag)] = e
+		}
+	}
+	if reqMask != u.reqMask && errLater == nil {
+		// A required field of this message is missing.
+		for _, n := range u.reqFields {
+			if reqMask&1 == 0 {
+				errLater = &RequiredNotSetError{n}
+			}
+			reqMask >>= 1
+		}
+	}
+	return errLater
+}
+
+// computeUnmarshalInfo fills in u with information for use
+// in unmarshaling protocol buffers of type u.typ.
+func (u *unmarshalInfo) computeUnmarshalInfo() {
+	u.lock.Lock()
+	defer u.lock.Unlock()
+	if u.initialized != 0 {
+		return
+	}
+	t := u.typ
+	n := t.NumField()
+
+	// Set up the "not found" value for the unrecognized byte buffer.
+	// This is the default for proto3.
+	u.unrecognized = invalidField
+	u.extensions = invalidField
+	u.oldExtensions = invalidField
+
+	// List of the generated type and offset for each oneof field.
+	type oneofField struct {
+		ityp  reflect.Type // interface type of oneof field
+		field field        // offset in containing message
+	}
+	var oneofFields []oneofField
+
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if f.Name == "XXX_unrecognized" {
+			// The byte slice used to hold unrecognized input is special.
+			if f.Type != reflect.TypeOf(([]byte)(nil)) {
+				panic("bad type for XXX_unrecognized field: " + f.Type.Name())
+			}
+			u.unrecognized = toField(&f)
+			continue
+		}
+		if f.Name == "XXX_InternalExtensions" {
+			// Ditto here.
+			if f.Type != reflect.TypeOf(XXX_InternalExtensions{}) {
+				panic("bad type for XXX_InternalExtensions field: " + f.Type.Name())
+			}
+			u.extensions = toField(&f)
+			if f.Tag.Get("protobuf_messageset") == "1" {
+				u.isMessageSet = true
+			}
+			continue
+		}
+		if f.Name == "XXX_extensions" {
+			// An older form of the extensions field.
+			if f.Type != reflect.TypeOf((map[int32]Extension)(nil)) {
+				panic("bad type for XXX_extensions field: " + f.Type.Name())
+			}
+			u.oldExtensions = toField(&f)
+			continue
+		}
+		if f.Name == "XXX_NoUnkeyedLiteral" || f.Name == "XXX_sizecache" {
+			continue
+		}
+
+		oneof := f.Tag.Get("protobuf_oneof")
+		if oneof != "" {
+			oneofFields = append(oneofFields, oneofField{f.Type, toField(&f)})
+			// The rest of oneof processing happens below.
+			continue
+		}
+
+		tags := f.Tag.Get("protobuf")
+		tagArray := strings.Split(tags, ",")
+		if len(tagArray) < 2 {
+			panic("protobuf tag not enough fields in " + t.Name() + "." + f.Name + ": " + tags)
+		}
+		tag, err := strconv.Atoi(tagArray[1])
+		if err != nil {
+			panic("protobuf tag field not an integer: " + tagArray[1])
+		}
+
+		name := ""
+		for _, tag := range tagArray[3:] {
+			if strings.HasPrefix(tag, "name=") {
+				name = tag[5:]
+			}
+		}
+
+		// Extract unmarshaling function from the field (its type and tags).
+		unmarshal := fieldUnmarshaler(&f)
+
+		// Required field?
+		var reqMask uint64
+		if tagArray[2] == "req" {
+			bit := len(u.reqFields)
+			u.reqFields = append(u.reqFields, name)
+			reqMask = uint64(1) << uint(bit)
+			// TODO: if we have more than 64 required fields, we end up
+			// not verifying that all required fields are present.
+			// Fix this, perhaps using a count of required fields?
+		}
+
+		// Store the info in the correct slot in the message.
+		u.setTag(tag, toField(&f), unmarshal, reqMask, name)
+	}
+
+	// Find any types associated with oneof fields.
+	var oneofImplementers []interface{}
+	switch m := reflect.Zero(reflect.PtrTo(t)).Interface().(type) {
+	case oneofFuncsIface:
+		_, _, _, oneofImplementers = m.XXX_OneofFuncs()
+	case oneofWrappersIface:
+		oneofImplementers = m.XXX_OneofWrappers()
+	}
+	for _, v := range oneofImplementers {
+		tptr := reflect.TypeOf(v) // *Msg_X
+		typ := tptr.Elem()        // Msg_X
+
+		f := typ.Field(0) // oneof implementers have one field
+		baseUnmarshal := fieldUnmarshaler(&f)
+		tags := strings.Split(f.Tag.Get("protobuf"), ",")
+		fieldNum, err := strconv.Atoi(tags[1])
+		if err != nil {
+			panic("protobuf tag field not an integer: " + tags[1])
+		}
+		var name string
+		for _, tag := range tags {
+			if strings.HasPrefix(tag, "name=") {
+				name = strings.TrimPrefix(tag, "name=")
+				break
+			}
+		}
+
+		// Find the oneof field that this struct implements.
+		// Might take O(n^2) to process all of the oneofs, but who cares.
+		for _, of := range oneofFields {
+			if tptr.Implements(of.ityp) {
+				// We have found the corresponding interface for this struct.
+				// That lets us know where this struct should be stored
+				// when we encounter it during unmarshaling.
+				unmarshal := makeUnmarshalOneof(typ, of.ityp, baseUnmarshal)
+				u.setTag(fieldNum, of.field, unmarshal, 0, name)
+			}
+		}
+
+	}
+
+	// Get extension ranges, if any.
+	fn := reflect.Zero(reflect.PtrTo(t)).MethodByName("ExtensionRangeArray")
+	if fn.IsValid() {
+		if !u.extensions.IsValid() && !u.oldExtensions.IsValid() {
+			panic("a message with extensions, but no extensions field in " + t.Name())
+		}
+		u.extensionRanges = fn.Call(nil)[0].Interface().([]ExtensionRange)
+	}
+
+	// Explicitly disallow tag 0. This will ensure we flag an error
+	// when decoding a buffer of all zeros. Without this code, we
+	// would decode and skip an all-zero buffer of even length.
+	// [0 0] is [tag=0/wiretype=varint varint-encoded-0].
+	u.setTag(0, zeroField, func(b []byte, f pointer, w int) ([]byte, error) {
+		return nil, fmt.Errorf("proto: %s: illegal tag 0 (wire type %d)", t, w)
+	}, 0, "")
+
+	// Set mask for required field check.
+	u.reqMask = uint64(1)<<uint(len(u.reqFields)) - 1
+
+	atomic.StoreInt32(&u.initialized, 1)
+}
+
+// setTag stores the unmarshal information for the given tag.
+// tag = tag # for field
+// field/unmarshal = unmarshal info for that field.
+// reqMask = if required, bitmask for field position in required field list. 0 otherwise.
+// name = short name of the field.
+func (u *unmarshalInfo) setTag(tag int, field field, unmarshal unmarshaler, reqMask uint64, name string) {
+	i := unmarshalFieldInfo{field: field, unmarshal: unmarshal, reqMask: reqMask, name: name}
+	n := u.typ.NumField()
+	if tag >= 0 && (tag < 16 || tag < 2*n) { // TODO: what are the right numbers here?
+		for len(u.dense) <= tag {
+			u.dense = append(u.dense, unmarshalFieldInfo{})
+		}
+		u.dense[tag] = i
+		return
+	}
+	if u.sparse == nil {
+		u.sparse = map[uint64]unmarshalFieldInfo{}
+	}
+	u.sparse[uint64(tag)] = i
+}
+
+// fieldUnmarshaler returns an unmarshaler for the given field.
+func fieldUnmarshaler(f *reflect.StructField) unmarshaler {
+	if f.Type.Kind() == reflect.Map {
+		return makeUnmarshalMap(f)
+	}
+	return typeUnmarshaler(f.Type, f.Tag.Get("protobuf"))
+}
+
+// typeUnmarshaler returns an unmarshaler for the given field type / field tag pair.
+func typeUnmarshaler(t reflect.Type, tags string) unmarshaler {
+	tagArray := strings.Split(tags, ",")
+	encoding := tagArray[0]
+	name := "unknown"
+	proto3 := false
+	validateUTF8 := true
+	for _, tag := range tagArray[3:] {
+		if strings.HasPrefix(tag, "name=") {
+			name = tag[5:]
+		}
+		if tag == "proto3" {
+			proto3 = true
+		}
+	}
+	validateUTF8 = validateUTF8 && proto3
+
+	// Figure out packaging (pointer, slice, or both)
+	slice := false
+	pointer := false
+	if t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8 {
+		slice = true
+		t = t.Elem()
+	}
+	if t.Kind() == reflect.Ptr {
+		pointer = true
+		t = t.Elem()
+	}
+
+	// We'll never have both pointer and slice for basic types.
+	if pointer && slice && t.Kind() != reflect.Struct {
+		panic("both pointer and slice for basic type in " + t.Name())
+	}
+
+	switch t.Kind() {
+	case reflect.Bool:
+		if pointer {
+			return unmarshalBoolPtr
+		}
+		if slice {
+			return unmarshalBoolSlice
+		}
+		return unmarshalBoolValue
+	case reflect.Int32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return unmarshalFixedS32Ptr
+			}
+			if slice {
+				return unmarshalFixedS32Slice
+			}
+			return unmarshalFixedS32Value
+		case "varint":
+			// this could be int32 or enum
+			if pointer {
+				return unmarshalInt32Ptr
+			}
+			if slice {
+				return unmarshalInt32Slice
+			}
+			return unmarshalInt32Value
+		case "zigzag32":
+			if pointer {
+				return unmarshalSint32Ptr
+			}
+			if slice {
+				return unmarshalSint32Slice
+			}
+			return unmarshalSint32Value
+		}
+	case reflect.Int64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return unmarshalFixedS64Ptr
+			}
+			if slice {
+				return unmarshalFixedS64Slice
+			}
+			return unmarshalFixedS64Value
+		case "varint":
+			if pointer {
+				return unmarshalInt64Ptr
+			}
+			if slice {
+				return unmarshalInt64Slice
+			}
+			return unmarshalInt64Value
+		case "zigzag64":
+			if pointer {
+				return unmarshalSint64Ptr
+			}
+			if slice {
+				return unmarshalSint64Slice
+			}
+			return unmarshalSint64Value
+		}
+	case reflect.Uint32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return unmarshalFixed32Ptr
+			}
+			if slice {
+				return unmarshalFixed32Slice
+			}
+			return unmarshalFixed32Value
+		case "varint":
+			if pointer {
+				return unmarshalUint32Ptr
+			}
+			if slice {
+				return unmarshalUint32Slice
+			}
+			return unmarshalUint32Value
+		}
+	case reflect.Uint64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return unmarshalFixed64Ptr
+			}
+			if slice {
+				return unmarshalFixed64Slice
+			}
+			return unmarshalFixed64Value
+		case "varint":
+			if pointer {
+				return unmarshalUint64Ptr
+			}
+			if slice {
+				return unmarshalUint64Slice
+			}
+			return unmarshalUint64Value
+		}
+	case reflect.Float32:
+		if pointer {
+			return unmarshalFloat32Ptr
+		}
+		if slice {
+			return unmarshalFloat32Slice
+		}
+		return unmarshalFloat32Value
+	case reflect.Float64:
+		if pointer {
+			return unmarshalFloat64Ptr
+		}
+		if slice {
+			return unmarshalFloat64Slice
+		}
+		return unmarshalFloat64Value
+	case reflect.Map:
+		panic("map type in typeUnmarshaler in " + t.Name())
+	case reflect.Slice:
+		if pointer {
+			panic("bad pointer in slice case in " + t.Name())
+		}
+		if slice {
+			return unmarshalBytesSlice
+		}
+		return unmarshalBytesValue
+	case reflect.String:
+		if validateUTF8 {
+			if pointer {
+				return unmarshalUTF8StringPtr
+			}
+			if slice {
+				return unmarshalUTF8StringSlice
+			}
+			return unmarshalUTF8StringValue
+		}
+		if pointer {
+			return unmarshalStringPtr
+		}
+		if slice {
+			return unmarshalStringSlice
+		}
+		return unmarshalStringValue
+	case reflect.Struct:
+		// message or group field
+		if !pointer {
+			panic(fmt.Sprintf("message/group field %s:%s without pointer", t, encoding))
+		}
+		switch encoding {
+		case "bytes":
+			if slice {
+				return makeUnmarshalMessageSlicePtr(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalMessagePtr(getUnmarshalInfo(t), name)
+		case "group":
+			if slice {
+				return makeUnmarshalGroupSlicePtr(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalGroupPtr(getUnmarshalInfo(t), name)
+		}
+	}
+	panic(fmt.Sprintf("unmarshaler not found type:%s encoding:%s", t, encoding))
+}
+
+// Below are all the unmarshalers for individual fields of various types.
+
+func unmarshalInt64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	*f.toInt64() = v
+	return b, nil
+}
+
+func unmarshalInt64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	*f.toInt64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalInt64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int64(x)
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalSint64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	*f.toInt64() = v
+	return b, nil
+}
+
+func unmarshalSint64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	*f.toInt64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalSint64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int64(x>>1) ^ int64(x)<<63>>63
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalUint64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	*f.toUint64() = v
+	return b, nil
+}
+
+func unmarshalUint64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	*f.toUint64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalUint64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := uint64(x)
+			s := f.toUint64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	s := f.toUint64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalInt32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	*f.toInt32() = v
+	return b, nil
+}
+
+func unmarshalInt32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	f.setInt32Ptr(v)
+	return b, nil
+}
+
+func unmarshalInt32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int32(x)
+			f.appendInt32Slice(v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	f.appendInt32Slice(v)
+	return b, nil
+}
+
+func unmarshalSint32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	*f.toInt32() = v
+	return b, nil
+}
+
+func unmarshalSint32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	f.setInt32Ptr(v)
+	return b, nil
+}
+
+func unmarshalSint32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int32(x>>1) ^ int32(x)<<31>>31
+			f.appendInt32Slice(v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	f.appendInt32Slice(v)
+	return b, nil
+}
+
+func unmarshalUint32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	*f.toUint32() = v
+	return b, nil
+}
+
+func unmarshalUint32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	*f.toUint32Ptr() = &v
+	return b, nil
+}
+
+func unmarshalUint32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := uint32(x)
+			s := f.toUint32Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	s := f.toUint32Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalFixed64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	*f.toUint64() = v
+	return b[8:], nil
+}
+
+func unmarshalFixed64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	*f.toUint64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFixed64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+			s := f.toUint64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	s := f.toUint64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	*f.toInt64() = v
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	*f.toInt64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFixed32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	*f.toUint32() = v
+	return b[4:], nil
+}
+
+func unmarshalFixed32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	*f.toUint32Ptr() = &v
+	return b[4:], nil
+}
+
+func unmarshalFixed32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+			s := f.toUint32Slice()
+			*s = append(*s, v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	s := f.toUint32Slice()
+	*s = append(*s, v)
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	*f.toInt32() = v
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	f.setInt32Ptr(v)
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+			f.appendInt32Slice(v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	f.appendInt32Slice(v)
+	return b[4:], nil
+}
+
+func unmarshalBoolValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	// Note: any length varint is allowed, even though any sane
+	// encoder will use one byte.
+	// See https://github.com/golang/protobuf/issues/76
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	// TODO: check if x>1? Tests seem to indicate no.
+	v := x != 0
+	*f.toBool() = v
+	return b[n:], nil
+}
+
+func unmarshalBoolPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := x != 0
+	*f.toBoolPtr() = &v
+	return b[n:], nil
+}
+
+func unmarshalBoolSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := x != 0
+			s := f.toBoolSlice()
+			*s = append(*s, v)
+			b = b[n:]
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := x != 0
+	s := f.toBoolSlice()
+	*s = append(*s, v)
+	return b[n:], nil
+}
+
+func unmarshalFloat64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	*f.toFloat64() = v
+	return b[8:], nil
+}
+
+func unmarshalFloat64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	*f.toFloat64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFloat64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+			s := f.toFloat64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	s := f.toFloat64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFloat32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	*f.toFloat32() = v
+	return b[4:], nil
+}
+
+func unmarshalFloat32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	*f.toFloat32Ptr() = &v
+	return b[4:], nil
+}
+
+func unmarshalFloat32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+			s := f.toFloat32Slice()
+			*s = append(*s, v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	s := f.toFloat32Slice()
+	*s = append(*s, v)
+	return b[4:], nil
+}
+
+func unmarshalStringValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toString() = v
+	return b[x:], nil
+}
+
+func unmarshalStringPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toStringPtr() = &v
+	return b[x:], nil
+}
+
+func unmarshalStringSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	s := f.toStringSlice()
+	*s = append(*s, v)
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toString() = v
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toStringPtr() = &v
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	s := f.toStringSlice()
+	*s = append(*s, v)
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+var emptyBuf [0]byte
+
+func unmarshalBytesValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	// The use of append here is a trick which avoids the zeroing
+	// that would be required if we used a make/copy pair.
+	// We append to emptyBuf instead of nil because we want
+	// a non-nil result even when the length is 0.
+	v := append(emptyBuf[:], b[:x]...)
+	*f.toBytes() = v
+	return b[x:], nil
+}
+
+func unmarshalBytesSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := append(emptyBuf[:], b[:x]...)
+	s := f.toBytesSlice()
+	*s = append(*s, v)
+	return b[x:], nil
+}
+
+func makeUnmarshalMessagePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireBytes {
+			return b, errInternalBadWireType
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		// First read the message field to see if something is there.
+		// The semantics of multiple submessages are weird.  Instead of
+		// the last one winning (as it is for all other fields), multiple
+		// submessages are merged.
+		v := f.getPointer()
+		if v.isNil() {
+			v = valToPointer(reflect.New(sub.typ))
+			f.setPointer(v)
+		}
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		return b[x:], err
+	}
+}
+
+func makeUnmarshalMessageSlicePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireBytes {
+			return b, errInternalBadWireType
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := valToPointer(reflect.New(sub.typ))
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		f.appendPointer(v)
+		return b[x:], err
+	}
+}
+
+func makeUnmarshalGroupPtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireStartGroup {
+			return b, errInternalBadWireType
+		}
+		x, y := findEndGroup(b)
+		if x < 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := f.getPointer()
+		if v.isNil() {
+			v = valToPointer(reflect.New(sub.typ))
+			f.setPointer(v)
+		}
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		return b[y:], err
+	}
+}
+
+func makeUnmarshalGroupSlicePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireStartGroup {
+			return b, errInternalBadWireType
+		}
+		x, y := findEndGroup(b)
+		if x < 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := valToPointer(reflect.New(sub.typ))
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		f.appendPointer(v)
+		return b[y:], err
+	}
+}
+
+func makeUnmarshalMap(f *reflect.StructField) unmarshaler {
+	t := f.Type
+	kt := t.Key()
+	vt := t.Elem()
+	unmarshalKey := typeUnmarshaler(kt, f.Tag.Get("protobuf_key"))
+	unmarshalVal := typeUnmarshaler(vt, f.Tag.Get("protobuf_val"))
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		// The map entry is a submessage. Figure out how big it is.
+		if w != WireBytes {
+			return nil, fmt.Errorf("proto: bad wiretype for map field: got %d want %d", w, WireBytes)
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		r := b[x:] // unused data to return
+		b = b[:x]  // data for map entry
+
+		// Note: we could use #keys * #values ~= 200 functions
+		// to do map decoding without reflection. Probably not worth it.
+		// Maps will be somewhat slow. Oh well.
+
+		// Read key and value from data.
+		var nerr nonFatal
+		k := reflect.New(kt)
+		v := reflect.New(vt)
+		for len(b) > 0 {
+			x, n := decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			wire := int(x) & 7
+			b = b[n:]
+
+			var err error
+			switch x >> 3 {
+			case 1:
+				b, err = unmarshalKey(b, valToPointer(k), wire)
+			case 2:
+				b, err = unmarshalVal(b, valToPointer(v), wire)
+			default:
+				err = errInternalBadWireType // skip unknown tag
+			}
+
+			if nerr.Merge(err) {
+				continue
+			}
+			if err != errInternalBadWireType {
+				return nil, err
+			}
+
+			// Skip past unknown fields.
+			b, err = skipField(b, wire)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		// Get map, allocate if needed.
+		m := f.asPointerTo(t).Elem() // an addressable map[K]T
+		if m.IsNil() {
+			m.Set(reflect.MakeMap(t))
+		}
+
+		// Insert into map.
+		m.SetMapIndex(k.Elem(), v.Elem())
+
+		return r, nerr.E
+	}
+}
+
+// makeUnmarshalOneof makes an unmarshaler for oneof fields.
+// for:
+// message Msg {
+//   oneof F {
+//     int64 X = 1;
+//     float64 Y = 2;
+//   }
+// }
+// typ is the type of the concrete entry for a oneof case (e.g. Msg_X).
+// ityp is the interface type of the oneof field (e.g. isMsg_F).
+// unmarshal is the unmarshaler for the base type of the oneof case (e.g. int64).
+// Note that this function will be called once for each case in the oneof.
+func makeUnmarshalOneof(typ, ityp reflect.Type, unmarshal unmarshaler) unmarshaler {
+	sf := typ.Field(0)
+	field0 := toField(&sf)
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		// Allocate holder for value.
+		v := reflect.New(typ)
+
+		// Unmarshal data into holder.
+		// We unmarshal into the first field of the holder object.
+		var err error
+		var nerr nonFatal
+		b, err = unmarshal(b, valToPointer(v).offset(field0), w)
+		if !nerr.Merge(err) {
+			return nil, err
+		}
+
+		// Write pointer to holder into target field.
+		f.asPointerTo(ityp).Elem().Set(v)
+
+		return b, nerr.E
+	}
+}
+
+// Error used by decode internally.
+var errInternalBadWireType = errors.New("proto: internal error: bad wiretype")
+
+// skipField skips past a field of type wire and returns the remaining bytes.
+func skipField(b []byte, wire int) ([]byte, error) {
+	switch wire {
+	case WireVarint:
+		_, k := decodeVarint(b)
+		if k == 0 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[k:]
+	case WireFixed32:
+		if len(b) < 4 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[4:]
+	case WireFixed64:
+		if len(b) < 8 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[8:]
+	case WireBytes:
+		m, k := decodeVarint(b)
+		if k == 0 || uint64(len(b)-k) < m {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[uint64(k)+m:]
+	case WireStartGroup:
+		_, i := findEndGroup(b)
+		if i == -1 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[i:]
+	default:
+		return b, fmt.Errorf("proto: can't skip unknown wire type %d", wire)
+	}
+	return b, nil
+}
+
+// findEndGroup finds the index of the next EndGroup tag.
+// Groups may be nested, so the "next" EndGroup tag is the first
+// unpaired EndGroup.
+// findEndGroup returns the indexes of the start and end of the EndGroup tag.
+// Returns (-1,-1) if it can't find one.
+func findEndGroup(b []byte) (int, int) {
+	depth := 1
+	i := 0
+	for {
+		x, n := decodeVarint(b[i:])
+		if n == 0 {
+			return -1, -1
+		}
+		j := i
+		i += n
+		switch x & 7 {
+		case WireVarint:
+			_, k := decodeVarint(b[i:])
+			if k == 0 {
+				return -1, -1
+			}
+			i += k
+		case WireFixed32:
+			if len(b)-4 < i {
+				return -1, -1
+			}
+			i += 4
+		case WireFixed64:
+			if len(b)-8 < i {
+				return -1, -1
+			}
+			i += 8
+		case WireBytes:
+			m, k := decodeVarint(b[i:])
+			if k == 0 {
+				return -1, -1
+			}
+			i += k
+			if uint64(len(b)-i) < m {
+				return -1, -1
+			}
+			i += int(m)
+		case WireStartGroup:
+			depth++
+		case WireEndGroup:
+			depth--
+			if depth == 0 {
+				return j, i
+			}
+		default:
+			return -1, -1
+		}
+	}
+}
+
+// encodeVarint appends a varint-encoded integer to b and returns the result.
+func encodeVarint(b []byte, x uint64) []byte {
+	for x >= 1<<7 {
+		b = append(b, byte(x&0x7f|0x80))
+		x >>= 7
+	}
+	return append(b, byte(x))
+}
+
+// decodeVarint reads a varint-encoded integer from b.
+// Returns the decoded integer and the number of bytes read.
+// If there is an error, it returns 0,0.
+func decodeVarint(b []byte) (uint64, int) {
+	var x, y uint64
+	if len(b) == 0 {
+		goto bad
+	}
+	x = uint64(b[0])
+	if x < 0x80 {
+		return x, 1
+	}
+	x -= 0x80
+
+	if len(b) <= 1 {
+		goto bad
+	}
+	y = uint64(b[1])
+	x += y << 7
+	if y < 0x80 {
+		return x, 2
+	}
+	x -= 0x80 << 7
+
+	if len(b) <= 2 {
+		goto bad
+	}
+	y = uint64(b[2])
+	x += y << 14
+	if y < 0x80 {
+		return x, 3
+	}
+	x -= 0x80 << 14
+
+	if len(b) <= 3 {
+		goto bad
+	}
+	y = uint64(b[3])
+	x += y << 21
+	if y < 0x80 {
+		return x, 4
+	}
+	x -= 0x80 << 21
+
+	if len(b) <= 4 {
+		goto bad
+	}
+	y = uint64(b[4])
+	x += y << 28
+	if y < 0x80 {
+		return x, 5
+	}
+	x -= 0x80 << 28
+
+	if len(b) <= 5 {
+		goto bad
+	}
+	y = uint64(b[5])
+	x += y << 35
+	if y < 0x80 {
+		return x, 6
+	}
+	x -= 0x80 << 35
+
+	if len(b) <= 6 {
+		goto bad
+	}
+	y = uint64(b[6])
+	x += y << 42
+	if y < 0x80 {
+		return x, 7
+	}
+	x -= 0x80 << 42
+
+	if len(b) <= 7 {
+		goto bad
+	}
+	y = uint64(b[7])
+	x += y << 49
+	if y < 0x80 {
+		return x, 8
+	}
+	x -= 0x80 << 49
+
+	if len(b) <= 8 {
+		goto bad
+	}
+	y = uint64(b[8])
+	x += y << 56
+	if y < 0x80 {
+		return x, 9
+	}
+	x -= 0x80 << 56
+
+	if len(b) <= 9 {
+		goto bad
+	}
+	y = uint64(b[9])
+	x += y << 63
+	if y < 2 {
+		return x, 10
+	}
+
+bad:
+	return 0, 0
+}
diff --git a/vendor/github.com/golang/protobuf/proto/text.go b/vendor/github.com/golang/protobuf/proto/text.go
index 965876bf03..1aaee725b4 100644
--- a/vendor/github.com/golang/protobuf/proto/text.go
+++ b/vendor/github.com/golang/protobuf/proto/text.go
@@ -50,7 +50,6 @@ import (
 var (
 	newline         = []byte("\n")
 	spaces          = []byte("                                        ")
-	gtNewline       = []byte(">\n")
 	endBraceNewline = []byte("}\n")
 	backslashN      = []byte{'\\', 'n'}
 	backslashR      = []byte{'\\', 'r'}
@@ -170,11 +169,6 @@ func writeName(w *textWriter, props *Properties) error {
 	return nil
 }
 
-// raw is the interface satisfied by RawMessage.
-type raw interface {
-	Bytes() []byte
-}
-
 func requiresQuotes(u string) bool {
 	// When type URL contains any characters except [0-9A-Za-z./\-]*, it must be quoted.
 	for _, ch := range u {
@@ -269,6 +263,10 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 		props := sprops.Prop[i]
 		name := st.Field(i).Name
 
+		if name == "XXX_NoUnkeyedLiteral" {
+			continue
+		}
+
 		if strings.HasPrefix(name, "XXX_") {
 			// There are two XXX_ fields:
 			//   XXX_unrecognized []byte
@@ -355,7 +353,7 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 						return err
 					}
 				}
-				if err := tm.writeAny(w, key, props.mkeyprop); err != nil {
+				if err := tm.writeAny(w, key, props.MapKeyProp); err != nil {
 					return err
 				}
 				if err := w.WriteByte('\n'); err != nil {
@@ -372,7 +370,7 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 							return err
 						}
 					}
-					if err := tm.writeAny(w, val, props.mvalprop); err != nil {
+					if err := tm.writeAny(w, val, props.MapValProp); err != nil {
 						return err
 					}
 					if err := w.WriteByte('\n'); err != nil {
@@ -436,12 +434,6 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 				return err
 			}
 		}
-		if b, ok := fv.Interface().(raw); ok {
-			if err := writeRaw(w, b.Bytes()); err != nil {
-				return err
-			}
-			continue
-		}
 
 		// Enums have a String method, so writeAny will work fine.
 		if err := tm.writeAny(w, fv, props); err != nil {
@@ -455,7 +447,7 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 
 	// Extensions (the XXX_extensions field).
 	pv := sv.Addr()
-	if _, ok := extendable(pv.Interface()); ok {
+	if _, err := extendable(pv.Interface()); err == nil {
 		if err := tm.writeExtensions(w, pv); err != nil {
 			return err
 		}
@@ -464,27 +456,6 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 	return nil
 }
 
-// writeRaw writes an uninterpreted raw message.
-func writeRaw(w *textWriter, b []byte) error {
-	if err := w.WriteByte('<'); err != nil {
-		return err
-	}
-	if !w.compact {
-		if err := w.WriteByte('\n'); err != nil {
-			return err
-		}
-	}
-	w.indent()
-	if err := writeUnknownStruct(w, b); err != nil {
-		return err
-	}
-	w.unindent()
-	if err := w.WriteByte('>'); err != nil {
-		return err
-	}
-	return nil
-}
-
 // writeAny writes an arbitrary field.
 func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Properties) error {
 	v = reflect.Indirect(v)
@@ -535,6 +506,19 @@ func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Propert
 			}
 		}
 		w.indent()
+		if v.CanAddr() {
+			// Calling v.Interface on a struct causes the reflect package to
+			// copy the entire struct. This is racy with the new Marshaler
+			// since we atomically update the XXX_sizecache.
+			//
+			// Thus, we retrieve a pointer to the struct if possible to avoid
+			// a race since v.Interface on the pointer doesn't copy the struct.
+			//
+			// If v is not addressable, then we are not worried about a race
+			// since it implies that the binary Marshaler cannot possibly be
+			// mutating this value.
+			v = v.Addr()
+		}
 		if etm, ok := v.Interface().(encoding.TextMarshaler); ok {
 			text, err := etm.MarshalText()
 			if err != nil {
@@ -543,8 +527,13 @@ func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Propert
 			if _, err = w.Write(text); err != nil {
 				return err
 			}
-		} else if err := tm.writeStruct(w, v); err != nil {
-			return err
+		} else {
+			if v.Kind() == reflect.Ptr {
+				v = v.Elem()
+			}
+			if err := tm.writeStruct(w, v); err != nil {
+				return err
+			}
 		}
 		w.unindent()
 		if err := w.WriteByte(ket); err != nil {
diff --git a/vendor/github.com/golang/protobuf/proto/text_parser.go b/vendor/github.com/golang/protobuf/proto/text_parser.go
index 5e14513f28..bb55a3af27 100644
--- a/vendor/github.com/golang/protobuf/proto/text_parser.go
+++ b/vendor/github.com/golang/protobuf/proto/text_parser.go
@@ -206,7 +206,6 @@ func (p *textParser) advance() {
 
 var (
 	errBadUTF8 = errors.New("proto: bad UTF-8")
-	errBadHex  = errors.New("proto: bad hexadecimal")
 )
 
 func unquoteC(s string, quote rune) (string, error) {
@@ -277,60 +276,47 @@ func unescape(s string) (ch string, tail string, err error) {
 		return "?", s, nil // trigraph workaround
 	case '\'', '"', '\\':
 		return string(r), s, nil
-	case '0', '1', '2', '3', '4', '5', '6', '7', 'x', 'X':
+	case '0', '1', '2', '3', '4', '5', '6', '7':
 		if len(s) < 2 {
 			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
 		}
-		base := 8
-		ss := s[:2]
+		ss := string(r) + s[:2]
 		s = s[2:]
-		if r == 'x' || r == 'X' {
-			base = 16
-		} else {
-			ss = string(r) + ss
-		}
-		i, err := strconv.ParseUint(ss, base, 8)
+		i, err := strconv.ParseUint(ss, 8, 8)
 		if err != nil {
-			return "", "", err
+			return "", "", fmt.Errorf(`\%s contains non-octal digits`, ss)
 		}
 		return string([]byte{byte(i)}), s, nil
-	case 'u', 'U':
-		n := 4
-		if r == 'U' {
+	case 'x', 'X', 'u', 'U':
+		var n int
+		switch r {
+		case 'x', 'X':
+			n = 2
+		case 'u':
+			n = 4
+		case 'U':
 			n = 8
 		}
 		if len(s) < n {
-			return "", "", fmt.Errorf(`\%c requires %d digits`, r, n)
-		}
-
-		bs := make([]byte, n/2)
-		for i := 0; i < n; i += 2 {
-			a, ok1 := unhex(s[i])
-			b, ok2 := unhex(s[i+1])
-			if !ok1 || !ok2 {
-				return "", "", errBadHex
-			}
-			bs[i/2] = a<<4 | b
+			return "", "", fmt.Errorf(`\%c requires %d following digits`, r, n)
 		}
+		ss := s[:n]
 		s = s[n:]
-		return string(bs), s, nil
+		i, err := strconv.ParseUint(ss, 16, 64)
+		if err != nil {
+			return "", "", fmt.Errorf(`\%c%s contains non-hexadecimal digits`, r, ss)
+		}
+		if r == 'x' || r == 'X' {
+			return string([]byte{byte(i)}), s, nil
+		}
+		if i > utf8.MaxRune {
+			return "", "", fmt.Errorf(`\%c%s is not a valid Unicode code point`, r, ss)
+		}
+		return string(i), s, nil
 	}
 	return "", "", fmt.Errorf(`unknown escape \%c`, r)
 }
 
-// Adapted from src/pkg/strconv/quote.go.
-func unhex(b byte) (v byte, ok bool) {
-	switch {
-	case '0' <= b && b <= '9':
-		return b - '0', true
-	case 'a' <= b && b <= 'f':
-		return b - 'a' + 10, true
-	case 'A' <= b && b <= 'F':
-		return b - 'A' + 10, true
-	}
-	return 0, false
-}
-
 // Back off the parser by one token. Can only be done between calls to next().
 // It makes the next advance() a no-op.
 func (p *textParser) back() { p.backed = true }
@@ -644,17 +630,17 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 					if err := p.consumeToken(":"); err != nil {
 						return err
 					}
-					if err := p.readAny(key, props.mkeyprop); err != nil {
+					if err := p.readAny(key, props.MapKeyProp); err != nil {
 						return err
 					}
 					if err := p.consumeOptionalSeparator(); err != nil {
 						return err
 					}
 				case "value":
-					if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
+					if err := p.checkForColon(props.MapValProp, dst.Type().Elem()); err != nil {
 						return err
 					}
-					if err := p.readAny(val, props.mvalprop); err != nil {
+					if err := p.readAny(val, props.MapValProp); err != nil {
 						return err
 					}
 					if err := p.consumeOptionalSeparator(); err != nil {
@@ -728,6 +714,9 @@ func (p *textParser) consumeExtName() (string, error) {
 		if tok.err != nil {
 			return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
 		}
+		if p.done && tok.value != "]" {
+			return "", p.errorf("unclosed type_url or extension name")
+		}
 	}
 	return strings.Join(parts, ""), nil
 }
@@ -865,7 +854,7 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 		return p.readStruct(fv, terminator)
 	case reflect.Uint32:
 		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
-			fv.SetUint(x)
+			fv.SetUint(uint64(x))
 			return nil
 		}
 	case reflect.Uint64:
@@ -883,13 +872,9 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 // UnmarshalText returns *RequiredNotSetError.
 func UnmarshalText(s string, pb Message) error {
 	if um, ok := pb.(encoding.TextUnmarshaler); ok {
-		err := um.UnmarshalText([]byte(s))
-		return err
+		return um.UnmarshalText([]byte(s))
 	}
 	pb.Reset()
 	v := reflect.ValueOf(pb)
-	if pe := newTextParser(s).readStruct(v.Elem(), ""); pe != nil {
-		return pe
-	}
-	return nil
+	return newTextParser(s).readStruct(v.Elem(), "")
 }
diff --git a/vendor/github.com/golang/protobuf/ptypes/any.go b/vendor/github.com/golang/protobuf/ptypes/any.go
index b2af97f4a9..70276e8f5c 100644
--- a/vendor/github.com/golang/protobuf/ptypes/any.go
+++ b/vendor/github.com/golang/protobuf/ptypes/any.go
@@ -130,10 +130,12 @@ func UnmarshalAny(any *any.Any, pb proto.Message) error {
 
 // Is returns true if any value contains a given message type.
 func Is(any *any.Any, pb proto.Message) bool {
-	aname, err := AnyMessageName(any)
-	if err != nil {
+	// The following is equivalent to AnyMessageName(any) == proto.MessageName(pb),
+	// but it avoids scanning TypeUrl for the slash.
+	if any == nil {
 		return false
 	}
-
-	return aname == proto.MessageName(pb)
+	name := proto.MessageName(pb)
+	prefix := len(any.TypeUrl) - len(name)
+	return prefix >= 1 && any.TypeUrl[prefix-1] == '/' && any.TypeUrl[prefix:] == name
 }
diff --git a/vendor/github.com/golang/protobuf/ptypes/any/any.pb.go b/vendor/github.com/golang/protobuf/ptypes/any/any.pb.go
index f34601723d..78ee523349 100644
--- a/vendor/github.com/golang/protobuf/ptypes/any/any.pb.go
+++ b/vendor/github.com/golang/protobuf/ptypes/any/any.pb.go
@@ -1,20 +1,13 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: google/protobuf/any.proto
 
-/*
-Package any is a generated protocol buffer package.
-
-It is generated from these files:
-	google/protobuf/any.proto
-
-It has these top-level messages:
-	Any
-*/
 package any
 
-import proto "github.com/golang/protobuf/proto"
-import fmt "fmt"
-import math "math"
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -25,7 +18,7 @@ var _ = math.Inf
 // is compatible with the proto package it is being compiled against.
 // A compilation error at this line likely means your copy of the
 // proto package needs to be updated.
-const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
 
 // `Any` contains an arbitrary serialized protocol buffer message along with a
 // URL that describes the type of the serialized message.
@@ -108,17 +101,18 @@ const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 //     }
 //
 type Any struct {
-	// A URL/resource name whose content describes the type of the
-	// serialized protocol buffer message.
+	// A URL/resource name that uniquely identifies the type of the serialized
+	// protocol buffer message. The last segment of the URL's path must represent
+	// the fully qualified name of the type (as in
+	// `path/google.protobuf.Duration`). The name should be in a canonical form
+	// (e.g., leading "." is not accepted).
 	//
-	// For URLs which use the scheme `http`, `https`, or no scheme, the
-	// following restrictions and interpretations apply:
+	// In practice, teams usually precompile into the binary all types that they
+	// expect it to use in the context of Any. However, for URLs which use the
+	// scheme `http`, `https`, or no scheme, one can optionally set up a type
+	// server that maps type URLs to message definitions as follows:
 	//
 	// * If no scheme is provided, `https` is assumed.
-	// * The last segment of the URL's path must represent the fully
-	//   qualified name of the type (as in `path/google.protobuf.Duration`).
-	//   The name should be in a canonical form (e.g., leading "." is
-	//   not accepted).
 	// * An HTTP GET on the URL must yield a [google.protobuf.Type][]
 	//   value in binary format, or produce an error.
 	// * Applications are allowed to cache lookup results based on the
@@ -127,19 +121,47 @@ type Any struct {
 	//   on changes to types. (Use versioned type names to manage
 	//   breaking changes.)
 	//
+	// Note: this functionality is not currently available in the official
+	// protobuf release, and it is not used for type URLs beginning with
+	// type.googleapis.com.
+	//
 	// Schemes other than `http`, `https` (or the empty scheme) might be
 	// used with implementation specific semantics.
 	//
-	TypeUrl string `protobuf:"bytes,1,opt,name=type_url,json=typeUrl" json:"type_url,omitempty"`
+	TypeUrl string `protobuf:"bytes,1,opt,name=type_url,json=typeUrl,proto3" json:"type_url,omitempty"`
 	// Must be a valid serialized protocol buffer of the above specified type.
-	Value []byte `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+	Value                []byte   `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Any) Reset()         { *m = Any{} }
+func (m *Any) String() string { return proto.CompactTextString(m) }
+func (*Any) ProtoMessage()    {}
+func (*Any) Descriptor() ([]byte, []int) {
+	return fileDescriptor_b53526c13ae22eb4, []int{0}
+}
+
+func (*Any) XXX_WellKnownType() string { return "Any" }
+
+func (m *Any) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Any.Unmarshal(m, b)
+}
+func (m *Any) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Any.Marshal(b, m, deterministic)
+}
+func (m *Any) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Any.Merge(m, src)
+}
+func (m *Any) XXX_Size() int {
+	return xxx_messageInfo_Any.Size(m)
+}
+func (m *Any) XXX_DiscardUnknown() {
+	xxx_messageInfo_Any.DiscardUnknown(m)
 }
 
-func (m *Any) Reset()                    { *m = Any{} }
-func (m *Any) String() string            { return proto.CompactTextString(m) }
-func (*Any) ProtoMessage()               {}
-func (*Any) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
-func (*Any) XXX_WellKnownType() string   { return "Any" }
+var xxx_messageInfo_Any proto.InternalMessageInfo
 
 func (m *Any) GetTypeUrl() string {
 	if m != nil {
@@ -159,9 +181,9 @@ func init() {
 	proto.RegisterType((*Any)(nil), "google.protobuf.Any")
 }
 
-func init() { proto.RegisterFile("google/protobuf/any.proto", fileDescriptor0) }
+func init() { proto.RegisterFile("google/protobuf/any.proto", fileDescriptor_b53526c13ae22eb4) }
 
-var fileDescriptor0 = []byte{
+var fileDescriptor_b53526c13ae22eb4 = []byte{
 	// 185 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x4c, 0xcf, 0xcf, 0x4f,
 	0xcf, 0x49, 0xd5, 0x2f, 0x28, 0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x4f, 0xcc, 0xab, 0xd4,
diff --git a/vendor/github.com/golang/protobuf/ptypes/any/any.proto b/vendor/github.com/golang/protobuf/ptypes/any/any.proto
index c748667623..4932942558 100644
--- a/vendor/github.com/golang/protobuf/ptypes/any/any.proto
+++ b/vendor/github.com/golang/protobuf/ptypes/any/any.proto
@@ -120,17 +120,18 @@ option objc_class_prefix = "GPB";
 //     }
 //
 message Any {
-  // A URL/resource name whose content describes the type of the
-  // serialized protocol buffer message.
+  // A URL/resource name that uniquely identifies the type of the serialized
+  // protocol buffer message. The last segment of the URL's path must represent
+  // the fully qualified name of the type (as in
+  // `path/google.protobuf.Duration`). The name should be in a canonical form
+  // (e.g., leading "." is not accepted).
   //
-  // For URLs which use the scheme `http`, `https`, or no scheme, the
-  // following restrictions and interpretations apply:
+  // In practice, teams usually precompile into the binary all types that they
+  // expect it to use in the context of Any. However, for URLs which use the
+  // scheme `http`, `https`, or no scheme, one can optionally set up a type
+  // server that maps type URLs to message definitions as follows:
   //
   // * If no scheme is provided, `https` is assumed.
-  // * The last segment of the URL's path must represent the fully
-  //   qualified name of the type (as in `path/google.protobuf.Duration`).
-  //   The name should be in a canonical form (e.g., leading "." is
-  //   not accepted).
   // * An HTTP GET on the URL must yield a [google.protobuf.Type][]
   //   value in binary format, or produce an error.
   // * Applications are allowed to cache lookup results based on the
@@ -139,6 +140,10 @@ message Any {
   //   on changes to types. (Use versioned type names to manage
   //   breaking changes.)
   //
+  // Note: this functionality is not currently available in the official
+  // protobuf release, and it is not used for type URLs beginning with
+  // type.googleapis.com.
+  //
   // Schemes other than `http`, `https` (or the empty scheme) might be
   // used with implementation specific semantics.
   //
diff --git a/vendor/github.com/golang/protobuf/ptypes/duration.go b/vendor/github.com/golang/protobuf/ptypes/duration.go
index 65cb0f8eb5..26d1ca2fb5 100644
--- a/vendor/github.com/golang/protobuf/ptypes/duration.go
+++ b/vendor/github.com/golang/protobuf/ptypes/duration.go
@@ -82,7 +82,7 @@ func Duration(p *durpb.Duration) (time.Duration, error) {
 		return 0, fmt.Errorf("duration: %v is out of range for time.Duration", p)
 	}
 	if p.Nanos != 0 {
-		d += time.Duration(p.Nanos)
+		d += time.Duration(p.Nanos) * time.Nanosecond
 		if (d < 0) != (p.Nanos < 0) {
 			return 0, fmt.Errorf("duration: %v is out of range for time.Duration", p)
 		}
diff --git a/vendor/github.com/golang/protobuf/ptypes/duration/duration.pb.go b/vendor/github.com/golang/protobuf/ptypes/duration/duration.pb.go
index b2410a098e..0d681ee21a 100644
--- a/vendor/github.com/golang/protobuf/ptypes/duration/duration.pb.go
+++ b/vendor/github.com/golang/protobuf/ptypes/duration/duration.pb.go
@@ -1,20 +1,13 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: google/protobuf/duration.proto
 
-/*
-Package duration is a generated protocol buffer package.
-
-It is generated from these files:
-	google/protobuf/duration.proto
-
-It has these top-level messages:
-	Duration
-*/
 package duration
 
-import proto "github.com/golang/protobuf/proto"
-import fmt "fmt"
-import math "math"
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -25,7 +18,7 @@ var _ = math.Inf
 // is compatible with the proto package it is being compiled against.
 // A compilation error at this line likely means your copy of the
 // proto package needs to be updated.
-const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
 
 // A Duration represents a signed, fixed-length span of time represented
 // as a count of seconds and fractions of seconds at nanosecond
@@ -91,21 +84,45 @@ type Duration struct {
 	// Signed seconds of the span of time. Must be from -315,576,000,000
 	// to +315,576,000,000 inclusive. Note: these bounds are computed from:
 	// 60 sec/min * 60 min/hr * 24 hr/day * 365.25 days/year * 10000 years
-	Seconds int64 `protobuf:"varint,1,opt,name=seconds" json:"seconds,omitempty"`
+	Seconds int64 `protobuf:"varint,1,opt,name=seconds,proto3" json:"seconds,omitempty"`
 	// Signed fractions of a second at nanosecond resolution of the span
 	// of time. Durations less than one second are represented with a 0
 	// `seconds` field and a positive or negative `nanos` field. For durations
 	// of one second or more, a non-zero value for the `nanos` field must be
 	// of the same sign as the `seconds` field. Must be from -999,999,999
 	// to +999,999,999 inclusive.
-	Nanos int32 `protobuf:"varint,2,opt,name=nanos" json:"nanos,omitempty"`
+	Nanos                int32    `protobuf:"varint,2,opt,name=nanos,proto3" json:"nanos,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Duration) Reset()         { *m = Duration{} }
+func (m *Duration) String() string { return proto.CompactTextString(m) }
+func (*Duration) ProtoMessage()    {}
+func (*Duration) Descriptor() ([]byte, []int) {
+	return fileDescriptor_23597b2ebd7ac6c5, []int{0}
+}
+
+func (*Duration) XXX_WellKnownType() string { return "Duration" }
+
+func (m *Duration) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Duration.Unmarshal(m, b)
+}
+func (m *Duration) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Duration.Marshal(b, m, deterministic)
+}
+func (m *Duration) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Duration.Merge(m, src)
+}
+func (m *Duration) XXX_Size() int {
+	return xxx_messageInfo_Duration.Size(m)
+}
+func (m *Duration) XXX_DiscardUnknown() {
+	xxx_messageInfo_Duration.DiscardUnknown(m)
 }
 
-func (m *Duration) Reset()                    { *m = Duration{} }
-func (m *Duration) String() string            { return proto.CompactTextString(m) }
-func (*Duration) ProtoMessage()               {}
-func (*Duration) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
-func (*Duration) XXX_WellKnownType() string   { return "Duration" }
+var xxx_messageInfo_Duration proto.InternalMessageInfo
 
 func (m *Duration) GetSeconds() int64 {
 	if m != nil {
@@ -125,9 +142,9 @@ func init() {
 	proto.RegisterType((*Duration)(nil), "google.protobuf.Duration")
 }
 
-func init() { proto.RegisterFile("google/protobuf/duration.proto", fileDescriptor0) }
+func init() { proto.RegisterFile("google/protobuf/duration.proto", fileDescriptor_23597b2ebd7ac6c5) }
 
-var fileDescriptor0 = []byte{
+var fileDescriptor_23597b2ebd7ac6c5 = []byte{
 	// 190 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x4b, 0xcf, 0xcf, 0x4f,
 	0xcf, 0x49, 0xd5, 0x2f, 0x28, 0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x4f, 0x29, 0x2d, 0x4a,
diff --git a/vendor/github.com/golang/protobuf/ptypes/regen.sh b/vendor/github.com/golang/protobuf/ptypes/regen.sh
deleted file mode 100755
index b50a9414ac..0000000000
--- a/vendor/github.com/golang/protobuf/ptypes/regen.sh
+++ /dev/null
@@ -1,43 +0,0 @@
-#!/bin/bash -e
-#
-# This script fetches and rebuilds the "well-known types" protocol buffers.
-# To run this you will need protoc and goprotobuf installed;
-# see https://github.com/golang/protobuf for instructions.
-# You also need Go and Git installed.
-
-PKG=github.com/golang/protobuf/ptypes
-UPSTREAM=https://github.com/google/protobuf
-UPSTREAM_SUBDIR=src/google/protobuf
-PROTO_FILES=(any duration empty struct timestamp wrappers)
-
-function die() {
-  echo 1>&2 $*
-  exit 1
-}
-
-# Sanity check that the right tools are accessible.
-for tool in go git protoc protoc-gen-go; do
-  q=$(which $tool) || die "didn't find $tool"
-  echo 1>&2 "$tool: $q"
-done
-
-tmpdir=$(mktemp -d -t regen-wkt.XXXXXX)
-trap 'rm -rf $tmpdir' EXIT
-
-echo -n 1>&2 "finding package dir... "
-pkgdir=$(go list -f '{{.Dir}}' $PKG)
-echo 1>&2 $pkgdir
-base=$(echo $pkgdir | sed "s,/$PKG\$,,")
-echo 1>&2 "base: $base"
-cd "$base"
-
-echo 1>&2 "fetching latest protos... "
-git clone -q $UPSTREAM $tmpdir
-
-for file in ${PROTO_FILES[@]}; do
-  echo 1>&2 "* $file"
-  protoc --go_out=. -I$tmpdir/src $tmpdir/src/google/protobuf/$file.proto || die
-  cp $tmpdir/src/google/protobuf/$file.proto $PKG/$file
-done
-
-echo 1>&2 "All OK"
diff --git a/vendor/github.com/golang/protobuf/ptypes/timestamp.go b/vendor/github.com/golang/protobuf/ptypes/timestamp.go
index 47f10dbc2c..8da0df01ac 100644
--- a/vendor/github.com/golang/protobuf/ptypes/timestamp.go
+++ b/vendor/github.com/golang/protobuf/ptypes/timestamp.go
@@ -111,11 +111,9 @@ func TimestampNow() *tspb.Timestamp {
 // TimestampProto converts the time.Time to a google.protobuf.Timestamp proto.
 // It returns an error if the resulting Timestamp is invalid.
 func TimestampProto(t time.Time) (*tspb.Timestamp, error) {
-	seconds := t.Unix()
-	nanos := int32(t.Sub(time.Unix(seconds, 0)))
 	ts := &tspb.Timestamp{
-		Seconds: seconds,
-		Nanos:   nanos,
+		Seconds: t.Unix(),
+		Nanos:   int32(t.Nanosecond()),
 	}
 	if err := validateTimestamp(ts); err != nil {
 		return nil, err
diff --git a/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.pb.go b/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.pb.go
index e23e4a25da..31cd846de9 100644
--- a/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.pb.go
+++ b/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.pb.go
@@ -1,20 +1,13 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: google/protobuf/timestamp.proto
 
-/*
-Package timestamp is a generated protocol buffer package.
-
-It is generated from these files:
-	google/protobuf/timestamp.proto
-
-It has these top-level messages:
-	Timestamp
-*/
 package timestamp
 
-import proto "github.com/golang/protobuf/proto"
-import fmt "fmt"
-import math "math"
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -25,7 +18,7 @@ var _ = math.Inf
 // is compatible with the proto package it is being compiled against.
 // A compilation error at this line likely means your copy of the
 // proto package needs to be updated.
-const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
 
 // A Timestamp represents a point in time independent of any time zone
 // or calendar, represented as seconds and fractions of seconds at
@@ -90,7 +83,9 @@ const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 // {hour}, {min}, and {sec} are zero-padded to two digits each. The fractional
 // seconds, which can go up to 9 digits (i.e. up to 1 nanosecond resolution),
 // are optional. The "Z" suffix indicates the timezone ("UTC"); the timezone
-// is required, though only UTC (as indicated by "Z") is presently supported.
+// is required. A proto3 JSON serializer should always use UTC (as indicated by
+// "Z") when printing the Timestamp type and a proto3 JSON parser should be
+// able to accept both UTC and other timezones (as indicated by an offset).
 //
 // For example, "2017-01-15T01:30:15.01Z" encodes 15.01 seconds past
 // 01:30 UTC on January 15, 2017.
@@ -101,27 +96,51 @@ const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 // to this format using [`strftime`](https://docs.python.org/2/library/time.html#time.strftime)
 // with the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one
 // can use the Joda Time's [`ISODateTimeFormat.dateTime()`](
-// http://joda-time.sourceforge.net/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime())
-// to obtain a formatter capable of generating timestamps in this format.
+// http://www.joda.org/joda-time/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime--
+// ) to obtain a formatter capable of generating timestamps in this format.
 //
 //
 type Timestamp struct {
 	// Represents seconds of UTC time since Unix epoch
 	// 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
 	// 9999-12-31T23:59:59Z inclusive.
-	Seconds int64 `protobuf:"varint,1,opt,name=seconds" json:"seconds,omitempty"`
+	Seconds int64 `protobuf:"varint,1,opt,name=seconds,proto3" json:"seconds,omitempty"`
 	// Non-negative fractions of a second at nanosecond resolution. Negative
 	// second values with fractions must still have non-negative nanos values
 	// that count forward in time. Must be from 0 to 999,999,999
 	// inclusive.
-	Nanos int32 `protobuf:"varint,2,opt,name=nanos" json:"nanos,omitempty"`
+	Nanos                int32    `protobuf:"varint,2,opt,name=nanos,proto3" json:"nanos,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Timestamp) Reset()         { *m = Timestamp{} }
+func (m *Timestamp) String() string { return proto.CompactTextString(m) }
+func (*Timestamp) ProtoMessage()    {}
+func (*Timestamp) Descriptor() ([]byte, []int) {
+	return fileDescriptor_292007bbfe81227e, []int{0}
+}
+
+func (*Timestamp) XXX_WellKnownType() string { return "Timestamp" }
+
+func (m *Timestamp) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Timestamp.Unmarshal(m, b)
+}
+func (m *Timestamp) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Timestamp.Marshal(b, m, deterministic)
+}
+func (m *Timestamp) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Timestamp.Merge(m, src)
+}
+func (m *Timestamp) XXX_Size() int {
+	return xxx_messageInfo_Timestamp.Size(m)
+}
+func (m *Timestamp) XXX_DiscardUnknown() {
+	xxx_messageInfo_Timestamp.DiscardUnknown(m)
 }
 
-func (m *Timestamp) Reset()                    { *m = Timestamp{} }
-func (m *Timestamp) String() string            { return proto.CompactTextString(m) }
-func (*Timestamp) ProtoMessage()               {}
-func (*Timestamp) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
-func (*Timestamp) XXX_WellKnownType() string   { return "Timestamp" }
+var xxx_messageInfo_Timestamp proto.InternalMessageInfo
 
 func (m *Timestamp) GetSeconds() int64 {
 	if m != nil {
@@ -141,9 +160,9 @@ func init() {
 	proto.RegisterType((*Timestamp)(nil), "google.protobuf.Timestamp")
 }
 
-func init() { proto.RegisterFile("google/protobuf/timestamp.proto", fileDescriptor0) }
+func init() { proto.RegisterFile("google/protobuf/timestamp.proto", fileDescriptor_292007bbfe81227e) }
 
-var fileDescriptor0 = []byte{
+var fileDescriptor_292007bbfe81227e = []byte{
 	// 191 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x4f, 0xcf, 0xcf, 0x4f,
 	0xcf, 0x49, 0xd5, 0x2f, 0x28, 0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x2f, 0xc9, 0xcc, 0x4d,
diff --git a/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.proto b/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.proto
index b7cbd17502..eafb3fa03a 100644
--- a/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.proto
+++ b/vendor/github.com/golang/protobuf/ptypes/timestamp/timestamp.proto
@@ -103,7 +103,9 @@ option objc_class_prefix = "GPB";
 // {hour}, {min}, and {sec} are zero-padded to two digits each. The fractional
 // seconds, which can go up to 9 digits (i.e. up to 1 nanosecond resolution),
 // are optional. The "Z" suffix indicates the timezone ("UTC"); the timezone
-// is required, though only UTC (as indicated by "Z") is presently supported.
+// is required. A proto3 JSON serializer should always use UTC (as indicated by
+// "Z") when printing the Timestamp type and a proto3 JSON parser should be
+// able to accept both UTC and other timezones (as indicated by an offset).
 //
 // For example, "2017-01-15T01:30:15.01Z" encodes 15.01 seconds past
 // 01:30 UTC on January 15, 2017.
@@ -114,8 +116,8 @@ option objc_class_prefix = "GPB";
 // to this format using [`strftime`](https://docs.python.org/2/library/time.html#time.strftime)
 // with the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one
 // can use the Joda Time's [`ISODateTimeFormat.dateTime()`](
-// http://joda-time.sourceforge.net/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime())
-// to obtain a formatter capable of generating timestamps in this format.
+// http://www.joda.org/joda-time/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime--
+// ) to obtain a formatter capable of generating timestamps in this format.
 //
 //
 message Timestamp {
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE b/vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE
new file mode 100644
index 0000000000..8dada3edaf
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "{}"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright {yyyy} {name of copyright owner}
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/NOTICE b/vendor/github.com/matttproud/golang_protobuf_extensions/NOTICE
new file mode 100644
index 0000000000..5d8cb5b72e
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/NOTICE
@@ -0,0 +1 @@
+Copyright 2012 Matt T. Proud (matt.proud@gmail.com)
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/.gitignore b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/.gitignore
new file mode 100644
index 0000000000..e16fb946bb
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/.gitignore
@@ -0,0 +1 @@
+cover.dat
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/Makefile b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/Makefile
new file mode 100644
index 0000000000..81be214370
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/Makefile
@@ -0,0 +1,7 @@
+all:
+
+cover:
+	go test -cover -v -coverprofile=cover.dat ./...
+	go tool cover -func cover.dat
+
+.PHONY: cover
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go
new file mode 100644
index 0000000000..258c0636aa
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go
@@ -0,0 +1,75 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+var errInvalidVarint = errors.New("invalid varint32 encountered")
+
+// ReadDelimited decodes a message from the provided length-delimited stream,
+// where the length is encoded as 32-bit varint prefix to the message body.
+// It returns the total number of bytes read and any applicable error.  This is
+// roughly equivalent to the companion Java API's
+// MessageLite#parseDelimitedFrom.  As per the reader contract, this function
+// calls r.Read repeatedly as required until exactly one message including its
+// prefix is read and decoded (or an error has occurred).  The function never
+// reads more bytes from the stream than required.  The function never returns
+// an error if a message has been read and decoded correctly, even if the end
+// of the stream has been reached in doing so.  In that case, any subsequent
+// calls return (0, io.EOF).
+func ReadDelimited(r io.Reader, m proto.Message) (n int, err error) {
+	// Per AbstractParser#parsePartialDelimitedFrom with
+	// CodedInputStream#readRawVarint32.
+	var headerBuf [binary.MaxVarintLen32]byte
+	var bytesRead, varIntBytes int
+	var messageLength uint64
+	for varIntBytes == 0 { // i.e. no varint has been decoded yet.
+		if bytesRead >= len(headerBuf) {
+			return bytesRead, errInvalidVarint
+		}
+		// We have to read byte by byte here to avoid reading more bytes
+		// than required. Each read byte is appended to what we have
+		// read before.
+		newBytesRead, err := r.Read(headerBuf[bytesRead : bytesRead+1])
+		if newBytesRead == 0 {
+			if err != nil {
+				return bytesRead, err
+			}
+			// A Reader should not return (0, nil), but if it does,
+			// it should be treated as no-op (according to the
+			// Reader contract). So let's go on...
+			continue
+		}
+		bytesRead += newBytesRead
+		// Now present everything read so far to the varint decoder and
+		// see if a varint can be decoded already.
+		messageLength, varIntBytes = proto.DecodeVarint(headerBuf[:bytesRead])
+	}
+
+	messageBuf := make([]byte, messageLength)
+	newBytesRead, err := io.ReadFull(r, messageBuf)
+	bytesRead += newBytesRead
+	if err != nil {
+		return bytesRead, err
+	}
+
+	return bytesRead, proto.Unmarshal(messageBuf, m)
+}
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go
new file mode 100644
index 0000000000..c318385cbe
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package pbutil provides record length-delimited Protocol Buffer streaming.
+package pbutil
diff --git a/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go
new file mode 100644
index 0000000000..8fb59ad226
--- /dev/null
+++ b/vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go
@@ -0,0 +1,46 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// WriteDelimited encodes and dumps a message to the provided writer prefixed
+// with a 32-bit varint indicating the length of the encoded message, producing
+// a length-delimited record stream, which can be used to chain together
+// encoded messages of the same type together in a file.  It returns the total
+// number of bytes written and any applicable error.  This is roughly
+// equivalent to the companion Java API's MessageLite#writeDelimitedTo.
+func WriteDelimited(w io.Writer, m proto.Message) (n int, err error) {
+	buffer, err := proto.Marshal(m)
+	if err != nil {
+		return 0, err
+	}
+
+	var buf [binary.MaxVarintLen32]byte
+	encodedLength := binary.PutUvarint(buf[:], uint64(len(buffer)))
+
+	sync, err := w.Write(buf[:encodedLength])
+	if err != nil {
+		return sync, err
+	}
+
+	n, err = w.Write(buffer)
+	return n + sync, err
+}
diff --git a/vendor/github.com/nginxinc/nginx-prometheus-exporter/LICENSE b/vendor/github.com/nginxinc/nginx-prometheus-exporter/LICENSE
new file mode 100644
index 0000000000..7933c0f5e5
--- /dev/null
+++ b/vendor/github.com/nginxinc/nginx-prometheus-exporter/LICENSE
@@ -0,0 +1,201 @@
+Apache License
+Version 2.0, January 2004
+http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+"License" shall mean the terms and conditions for use, reproduction,
+and distribution as defined by Sections 1 through 9 of this document.
+
+"Licensor" shall mean the copyright owner or entity authorized by
+the copyright owner that is granting the License.
+
+"Legal Entity" shall mean the union of the acting entity and all
+other entities that control, are controlled by, or are under common
+control with that entity. For the purposes of this definition,
+"control" means (i) the power, direct or indirect, to cause the
+direction or management of such entity, whether by contract or
+otherwise, or (ii) ownership of fifty percent (50%) or more of the
+outstanding shares, or (iii) beneficial ownership of such entity.
+
+"You" (or "Your") shall mean an individual or Legal Entity
+exercising permissions granted by this License.
+
+"Source" form shall mean the preferred form for making modifications,
+including but not limited to software source code, documentation
+source, and configuration files.
+
+"Object" form shall mean any form resulting from mechanical
+transformation or translation of a Source form, including but
+not limited to compiled object code, generated documentation,
+and conversions to other media types.
+
+"Work" shall mean the work of authorship, whether in Source or
+Object form, made available under the License, as indicated by a
+copyright notice that is included in or attached to the work
+(an example is provided in the Appendix below).
+
+"Derivative Works" shall mean any work, whether in Source or Object
+form, that is based on (or derived from) the Work and for which the
+editorial revisions, annotations, elaborations, or other modifications
+represent, as a whole, an original work of authorship. For the purposes
+of this License, Derivative Works shall not include works that remain
+separable from, or merely link (or bind by name) to the interfaces of,
+the Work and Derivative Works thereof.
+
+"Contribution" shall mean any work of authorship, including
+the original version of the Work and any modifications or additions
+to that Work or Derivative Works thereof, that is intentionally
+submitted to Licensor for inclusion in the Work by the copyright owner
+or by an individual or Legal Entity authorized to submit on behalf of
+the copyright owner. For the purposes of this definition, "submitted"
+means any form of electronic, verbal, or written communication sent
+to the Licensor or its representatives, including but not limited to
+communication on electronic mailing lists, source code control systems,
+and issue tracking systems that are managed by, or on behalf of, the
+Licensor for the purpose of discussing and improving the Work, but
+excluding communication that is conspicuously marked or otherwise
+designated in writing by the copyright owner as "Not a Contribution."
+
+"Contributor" shall mean Licensor and any individual or Legal Entity
+on behalf of whom a Contribution has been received by Licensor and
+subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
+this License, each Contributor hereby grants to You a perpetual,
+worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+copyright license to reproduce, prepare Derivative Works of,
+publicly display, publicly perform, sublicense, and distribute the
+Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of
+this License, each Contributor hereby grants to You a perpetual,
+worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+(except as stated in this section) patent license to make, have made,
+use, offer to sell, sell, import, and otherwise transfer the Work,
+where such license applies only to those patent claims licensable
+by such Contributor that are necessarily infringed by their
+Contribution(s) alone or by combination of their Contribution(s)
+with the Work to which such Contribution(s) was submitted. If You
+institute patent litigation against any entity (including a
+cross-claim or counterclaim in a lawsuit) alleging that the Work
+or a Contribution incorporated within the Work constitutes direct
+or contributory patent infringement, then any patent licenses
+granted to You under this License for that Work shall terminate
+as of the date such litigation is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the
+Work or Derivative Works thereof in any medium, with or without
+modifications, and in Source or Object form, provided that You
+meet the following conditions:
+
+(a) You must give any other recipients of the Work or
+Derivative Works a copy of this License; and
+
+(b) You must cause any modified files to carry prominent notices
+stating that You changed the files; and
+
+(c) You must retain, in the Source form of any Derivative Works
+that You distribute, all copyright, patent, trademark, and
+attribution notices from the Source form of the Work,
+excluding those notices that do not pertain to any part of
+the Derivative Works; and
+
+(d) If the Work includes a "NOTICE" text file as part of its
+distribution, then any Derivative Works that You distribute must
+include a readable copy of the attribution notices contained
+within such NOTICE file, excluding those notices that do not
+pertain to any part of the Derivative Works, in at least one
+of the following places: within a NOTICE text file distributed
+as part of the Derivative Works; within the Source form or
+documentation, if provided along with the Derivative Works; or,
+within a display generated by the Derivative Works, if and
+wherever such third-party notices normally appear. The contents
+of the NOTICE file are for informational purposes only and
+do not modify the License. You may add Your own attribution
+notices within Derivative Works that You distribute, alongside
+or as an addendum to the NOTICE text from the Work, provided
+that such additional attribution notices cannot be construed
+as modifying the License.
+
+You may add Your own copyright statement to Your modifications and
+may provide additional or different license terms and conditions
+for use, reproduction, or distribution of Your modifications, or
+for any such Derivative Works as a whole, provided Your use,
+reproduction, and distribution of the Work otherwise complies with
+the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+any Contribution intentionally submitted for inclusion in the Work
+by You to the Licensor shall be under the terms and conditions of
+this License, without any additional terms or conditions.
+Notwithstanding the above, nothing herein shall supersede or modify
+the terms of any separate license agreement you may have executed
+with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+names, trademarks, service marks, or product names of the Licensor,
+except as required for reasonable and customary use in describing the
+origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+agreed to in writing, Licensor provides the Work (and each
+Contributor provides its Contributions) on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+implied, including, without limitation, any warranties or conditions
+of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+PARTICULAR PURPOSE. You are solely responsible for determining the
+appropriateness of using or redistributing the Work and assume any
+risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+whether in tort (including negligence), contract, or otherwise,
+unless required by applicable law (such as deliberate and grossly
+negligent acts) or agreed to in writing, shall any Contributor be
+liable to You for damages, including any direct, indirect, special,
+incidental, or consequential damages of any character arising as a
+result of this License or out of the use or inability to use the
+Work (including but not limited to damages for loss of goodwill,
+work stoppage, computer failure or malfunction, or any and all
+other commercial damages or losses), even if such Contributor
+has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+the Work or Derivative Works thereof, You may choose to offer,
+and charge a fee for, acceptance of support, warranty, indemnity,
+or other liability obligations and/or rights consistent with this
+License. However, in accepting such obligations, You may act only
+on Your own behalf and on Your sole responsibility, not on behalf
+of any other Contributor, and only if You agree to indemnify,
+defend, and hold each Contributor harmless for any liability
+incurred by, or claims asserted against, such Contributor by reason
+of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+To apply the Apache License to your work, attach the following
+boilerplate notice, with the fields enclosed by brackets "{}"
+replaced with your own identifying information. (Don't include
+the brackets!)  The text should be enclosed in the appropriate
+comment syntax for the file format. We also recommend that a
+file or class name and description of purpose be included on the
+same "printed page" as the copyright notice for easier
+identification within third-party archives.
+
+Copyright 2018 Nginx, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
\ No newline at end of file
diff --git a/vendor/github.com/nginxinc/nginx-prometheus-exporter/client/nginx.go b/vendor/github.com/nginxinc/nginx-prometheus-exporter/client/nginx.go
new file mode 100644
index 0000000000..6ea5d05dc4
--- /dev/null
+++ b/vendor/github.com/nginxinc/nginx-prometheus-exporter/client/nginx.go
@@ -0,0 +1,139 @@
+package client
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+// NginxClient allows you to fetch NGINX metrics from the stub_status page.
+type NginxClient struct {
+	apiEndpoint string
+	httpClient  *http.Client
+}
+
+// StubStats represents NGINX stub_status metrics.
+type StubStats struct {
+	Connections StubConnections
+	Requests    int64
+}
+
+// StubConnections represents connections related metrics.
+type StubConnections struct {
+	Active   int64
+	Accepted int64
+	Handled  int64
+	Reading  int64
+	Writing  int64
+	Waiting  int64
+}
+
+// NewNginxClient creates an NginxClient.
+func NewNginxClient(httpClient *http.Client, apiEndpoint string) (*NginxClient, error) {
+	client := &NginxClient{
+		apiEndpoint: apiEndpoint,
+		httpClient:  httpClient,
+	}
+
+	if _, err := client.GetStubStats(); err != nil {
+		return nil, fmt.Errorf("Failed to create NginxClient: %v", err)
+	}
+
+	return client, nil
+}
+
+// GetStubStats fetches the stub_status metrics.
+func (client *NginxClient) GetStubStats() (*StubStats, error) {
+	resp, err := client.httpClient.Get(client.apiEndpoint)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get %v: %v", client.apiEndpoint, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("expected %v response, got %v", http.StatusOK, resp.StatusCode)
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read the response body: %v", err)
+	}
+
+	var stats StubStats
+	err = parseStubStats(body, &stats)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse response body %q: %v", string(body), err)
+	}
+
+	return &stats, nil
+}
+
+func parseStubStats(data []byte, stats *StubStats) error {
+	dataStr := string(data)
+
+	parts := strings.Split(dataStr, "\n")
+	if len(parts) != 5 {
+		return fmt.Errorf("invalid input %q", dataStr)
+	}
+
+	activeConsParts := strings.Split(strings.TrimSpace(parts[0]), " ")
+	if len(activeConsParts) != 3 {
+		return fmt.Errorf("invalid input for active connections %q", parts[0])
+	}
+
+	actCons, err := strconv.ParseInt(activeConsParts[2], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for active connections %q: %v", activeConsParts[2], err)
+	}
+	stats.Connections.Active = actCons
+
+	miscParts := strings.Split(strings.TrimSpace(parts[2]), " ")
+	if len(miscParts) != 3 {
+		return fmt.Errorf("invalid input for connections and requests %q", parts[2])
+	}
+
+	acceptedCons, err := strconv.ParseInt(miscParts[0], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for accepted connections %q: %v", miscParts[0], err)
+	}
+	stats.Connections.Accepted = acceptedCons
+
+	handledCons, err := strconv.ParseInt(miscParts[1], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for handled connections %q: %v", miscParts[1], err)
+	}
+	stats.Connections.Handled = handledCons
+
+	requests, err := strconv.ParseInt(miscParts[2], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for requests %q: %v", miscParts[2], err)
+	}
+	stats.Requests = requests
+
+	consParts := strings.Split(strings.TrimSpace(parts[3]), " ")
+	if len(consParts) != 6 {
+		return fmt.Errorf("invalid input for connections %q", parts[3])
+	}
+
+	readingCons, err := strconv.ParseInt(consParts[1], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for reading connections %q: %v", consParts[1], err)
+	}
+	stats.Connections.Reading = readingCons
+
+	writingCons, err := strconv.ParseInt(consParts[3], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for writing connections %q: %v", consParts[3], err)
+	}
+	stats.Connections.Writing = writingCons
+
+	waitingCons, err := strconv.ParseInt(consParts[5], 10, 64)
+	if err != nil {
+		return fmt.Errorf("invalid input for waiting connections %q: %v", consParts[5], err)
+	}
+	stats.Connections.Waiting = waitingCons
+
+	return nil
+}
diff --git a/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/helper.go b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/helper.go
new file mode 100644
index 0000000000..6fcd67e397
--- /dev/null
+++ b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/helper.go
@@ -0,0 +1,18 @@
+package collector
+
+import "github.com/prometheus/client_golang/prometheus"
+
+const nginxUp = 1
+const nginxDown = 0
+
+func newGlobalMetric(namespace string, metricName string, docString string) *prometheus.Desc {
+	return prometheus.NewDesc(namespace+"_"+metricName, docString, nil, nil)
+}
+
+func newUpMetric(namespace string) prometheus.Gauge {
+	return prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: namespace,
+		Name:      "up",
+		Help:      "Status of the last metric scrape",
+	})
+}
diff --git a/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx.go b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx.go
new file mode 100644
index 0000000000..2ac0bca0ce
--- /dev/null
+++ b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx.go
@@ -0,0 +1,76 @@
+package collector
+
+import (
+	"log"
+	"sync"
+
+	"github.com/nginxinc/nginx-prometheus-exporter/client"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// NginxCollector collects NGINX metrics. It implements prometheus.Collector interface.
+type NginxCollector struct {
+	nginxClient *client.NginxClient
+	metrics     map[string]*prometheus.Desc
+	upMetric    prometheus.Gauge
+	mutex       sync.Mutex
+}
+
+// NewNginxCollector creates an NginxCollector.
+func NewNginxCollector(nginxClient *client.NginxClient, namespace string) *NginxCollector {
+	return &NginxCollector{
+		nginxClient: nginxClient,
+		metrics: map[string]*prometheus.Desc{
+			"connections_active":   newGlobalMetric(namespace, "connections_active", "Active client connections"),
+			"connections_accepted": newGlobalMetric(namespace, "connections_accepted", "Accepted client connections"),
+			"connections_handled":  newGlobalMetric(namespace, "connections_handled", "Handled client connections"),
+			"connections_reading":  newGlobalMetric(namespace, "connections_reading", "Connections where NGINX is reading the request header"),
+			"connections_writing":  newGlobalMetric(namespace, "connections_writing", "Connections where NGINX is writing the response back to the client"),
+			"connections_waiting":  newGlobalMetric(namespace, "connections_waiting", "Idle client connections"),
+			"http_requests_total":  newGlobalMetric(namespace, "http_requests_total", "Total http requests"),
+		},
+		upMetric: newUpMetric(namespace),
+	}
+}
+
+// Describe sends the super-set of all possible descriptors of NGINX metrics
+// to the provided channel.
+func (c *NginxCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- c.upMetric.Desc()
+
+	for _, m := range c.metrics {
+		ch <- m
+	}
+}
+
+// Collect fetches metrics from NGINX and sends them to the provided channel.
+func (c *NginxCollector) Collect(ch chan<- prometheus.Metric) {
+	c.mutex.Lock() // To protect metrics from concurrent collects
+	defer c.mutex.Unlock()
+
+	stats, err := c.nginxClient.GetStubStats()
+	if err != nil {
+		c.upMetric.Set(nginxDown)
+		ch <- c.upMetric
+		log.Printf("Error getting stats: %v", err)
+		return
+	}
+
+	c.upMetric.Set(nginxUp)
+	ch <- c.upMetric
+
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_active"],
+		prometheus.GaugeValue, float64(stats.Connections.Active))
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_accepted"],
+		prometheus.CounterValue, float64(stats.Connections.Accepted))
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_handled"],
+		prometheus.CounterValue, float64(stats.Connections.Handled))
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_reading"],
+		prometheus.GaugeValue, float64(stats.Connections.Reading))
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_writing"],
+		prometheus.GaugeValue, float64(stats.Connections.Writing))
+	ch <- prometheus.MustNewConstMetric(c.metrics["connections_waiting"],
+		prometheus.GaugeValue, float64(stats.Connections.Waiting))
+	ch <- prometheus.MustNewConstMetric(c.metrics["http_requests_total"],
+		prometheus.CounterValue, float64(stats.Requests))
+}
diff --git a/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx_plus.go b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx_plus.go
new file mode 100644
index 0000000000..01524aa7c4
--- /dev/null
+++ b/vendor/github.com/nginxinc/nginx-prometheus-exporter/collector/nginx_plus.go
@@ -0,0 +1,325 @@
+package collector
+
+import (
+	"log"
+	"sync"
+
+	plusclient "github.com/nginxinc/nginx-plus-go-sdk/client"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// NginxPlusCollector collects NGINX Plus metrics. It implements prometheus.Collector interface.
+type NginxPlusCollector struct {
+	nginxClient                 *plusclient.NginxClient
+	totalMetrics                map[string]*prometheus.Desc
+	serverZoneMetrics           map[string]*prometheus.Desc
+	upstreamMetrics             map[string]*prometheus.Desc
+	upstreamServerMetrics       map[string]*prometheus.Desc
+	streamServerZoneMetrics     map[string]*prometheus.Desc
+	streamUpstreamMetrics       map[string]*prometheus.Desc
+	streamUpstreamServerMetrics map[string]*prometheus.Desc
+	upMetric                    prometheus.Gauge
+	mutex                       sync.Mutex
+}
+
+// NewNginxPlusCollector creates an NginxPlusCollector.
+func NewNginxPlusCollector(nginxClient *plusclient.NginxClient, namespace string) *NginxPlusCollector {
+	return &NginxPlusCollector{
+		nginxClient: nginxClient,
+		totalMetrics: map[string]*prometheus.Desc{
+			"connections_accepted":  newGlobalMetric(namespace, "connections_accepted", "Accepted client connections"),
+			"connections_dropped":   newGlobalMetric(namespace, "connections_dropped", "Dropped client connections"),
+			"connections_active":    newGlobalMetric(namespace, "connections_active", "Active client connections"),
+			"connections_idle":      newGlobalMetric(namespace, "connections_idle", "Idle client connections"),
+			"http_requests_total":   newGlobalMetric(namespace, "http_requests_total", "Total http requests"),
+			"http_requests_current": newGlobalMetric(namespace, "http_requests_current", "Current http requests"),
+			"ssl_handshakes":        newGlobalMetric(namespace, "ssl_handshakes", "Successful SSL handshakes"),
+			"ssl_handshakes_failed": newGlobalMetric(namespace, "ssl_handshakes_failed", "Failed SSL handshakes"),
+			"ssl_session_reuses":    newGlobalMetric(namespace, "ssl_session_reuses", "Session reuses during SSL handshake"),
+		},
+		serverZoneMetrics: map[string]*prometheus.Desc{
+			"processing":    newServerZoneMetric(namespace, "processing", "Client requests that are currently being processed", nil),
+			"requests":      newServerZoneMetric(namespace, "requests", "Total client requests", nil),
+			"responses_1xx": newServerZoneMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "1xx"}),
+			"responses_2xx": newServerZoneMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "2xx"}),
+			"responses_3xx": newServerZoneMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "3xx"}),
+			"responses_4xx": newServerZoneMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "4xx"}),
+			"responses_5xx": newServerZoneMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "5xx"}),
+			"discarded":     newServerZoneMetric(namespace, "discarded", "Requests completed without sending a response", nil),
+			"received":      newServerZoneMetric(namespace, "received", "Bytes received from clients", nil),
+			"sent":          newServerZoneMetric(namespace, "sent", "Bytes sent to clients", nil),
+		},
+		streamServerZoneMetrics: map[string]*prometheus.Desc{
+			"processing":   newStreamServerZoneMetric(namespace, "processing", "Client connections that are currently being processed", nil),
+			"connections":  newStreamServerZoneMetric(namespace, "connections", "Total connections", nil),
+			"sessions_2xx": newStreamServerZoneMetric(namespace, "sessions", "Total sessions completed", prometheus.Labels{"code": "2xx"}),
+			"sessions_4xx": newStreamServerZoneMetric(namespace, "sessions", "Total sessions completed", prometheus.Labels{"code": "4xx"}),
+			"sessions_5xx": newStreamServerZoneMetric(namespace, "sessions", "Total sessions completed", prometheus.Labels{"code": "5xx"}),
+			"discarded":    newStreamServerZoneMetric(namespace, "discarded", "Connections completed without creating a session", nil),
+			"received":     newStreamServerZoneMetric(namespace, "received", "Bytes received from clients", nil),
+			"sent":         newStreamServerZoneMetric(namespace, "sent", "Bytes sent to clients", nil),
+		},
+		upstreamMetrics: map[string]*prometheus.Desc{
+			"keepalives": newUpstreamMetric(namespace, "keepalives", "Idle keepalive connections"),
+			"zombies":    newUpstreamMetric(namespace, "zombies", "Servers removed from the group but still processing active client requests"),
+		},
+		streamUpstreamMetrics: map[string]*prometheus.Desc{
+			"zombies": newStreamUpstreamMetric(namespace, "zombies", "Servers removed from the group but still processing active client connections"),
+		},
+		upstreamServerMetrics: map[string]*prometheus.Desc{
+			"state":                   newUpstreamServerMetric(namespace, "state", "Current state", nil),
+			"active":                  newUpstreamServerMetric(namespace, "active", "Active connections", nil),
+			"requests":                newUpstreamServerMetric(namespace, "requests", "Total client requests", nil),
+			"responses_1xx":           newUpstreamServerMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "1xx"}),
+			"responses_2xx":           newUpstreamServerMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "2xx"}),
+			"responses_3xx":           newUpstreamServerMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "3xx"}),
+			"responses_4xx":           newUpstreamServerMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "4xx"}),
+			"responses_5xx":           newUpstreamServerMetric(namespace, "responses", "Total responses sent to clients", prometheus.Labels{"code": "5xx"}),
+			"sent":                    newUpstreamServerMetric(namespace, "sent", "Bytes sent to this server", nil),
+			"received":                newUpstreamServerMetric(namespace, "received", "Bytes received to this server", nil),
+			"fails":                   newUpstreamServerMetric(namespace, "fails", "Active connections", nil),
+			"unavail":                 newUpstreamServerMetric(namespace, "unavail", "How many times the server became unavailable for client requests (state 'unavail') due to the number of unsuccessful attempts reaching the max_fails threshold", nil),
+			"header_time":             newUpstreamServerMetric(namespace, "header_time", "Average time to get the response header from the server", nil),
+			"response_time":           newUpstreamServerMetric(namespace, "response_time", "Average time to get the full response from the server", nil),
+			"health_checks_checks":    newUpstreamServerMetric(namespace, "health_checks_checks", "Total health check requests", nil),
+			"health_checks_fails":     newUpstreamServerMetric(namespace, "health_checks_fails", "Failed health checks", nil),
+			"health_checks_unhealthy": newUpstreamServerMetric(namespace, "health_checks_unhealthy", "How many times the server became unhealthy (state 'unhealthy')", nil),
+		},
+		streamUpstreamServerMetrics: map[string]*prometheus.Desc{
+			"state":                   newStreamUpstreamServerMetric(namespace, "state", "Current state"),
+			"active":                  newStreamUpstreamServerMetric(namespace, "active", "Active connections"),
+			"sent":                    newStreamUpstreamServerMetric(namespace, "sent", "Bytes sent to this server"),
+			"received":                newStreamUpstreamServerMetric(namespace, "received", "Bytes received from this server"),
+			"fails":                   newStreamUpstreamServerMetric(namespace, "fails", "Number of unsuccessful attempts to communicate with the server"),
+			"unavail":                 newStreamUpstreamServerMetric(namespace, "unavail", "How many times the server became unavailable for client connections (state 'unavail') due to the number of unsuccessful attempts reaching the max_fails threshold"),
+			"connections":             newStreamUpstreamServerMetric(namespace, "connections", "Total number of client connections forwarded to this server"),
+			"connect_time":            newStreamUpstreamServerMetric(namespace, "connect_time", "Average time to connect to the upstream server"),
+			"first_byte_time":         newStreamUpstreamServerMetric(namespace, "first_byte_time", "Average time to receive the first byte of data"),
+			"response_time":           newStreamUpstreamServerMetric(namespace, "response_time", "Average time to receive the last byte of data"),
+			"health_checks_checks":    newStreamUpstreamServerMetric(namespace, "health_checks_checks", "Total health check requests"),
+			"health_checks_fails":     newStreamUpstreamServerMetric(namespace, "health_checks_fails", "Failed health checks"),
+			"health_checks_unhealthy": newStreamUpstreamServerMetric(namespace, "health_checks_unhealthy", "How many times the server became unhealthy (state 'unhealthy')"),
+		},
+		upMetric: newUpMetric(namespace),
+	}
+}
+
+// Describe sends the super-set of all possible descriptors of NGINX Plus metrics
+// to the provided channel.
+func (c *NginxPlusCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- c.upMetric.Desc()
+
+	for _, m := range c.totalMetrics {
+		ch <- m
+	}
+	for _, m := range c.serverZoneMetrics {
+		ch <- m
+	}
+	for _, m := range c.upstreamMetrics {
+		ch <- m
+	}
+	for _, m := range c.upstreamServerMetrics {
+		ch <- m
+	}
+	for _, m := range c.streamServerZoneMetrics {
+		ch <- m
+	}
+	for _, m := range c.streamUpstreamMetrics {
+		ch <- m
+	}
+	for _, m := range c.streamUpstreamServerMetrics {
+		ch <- m
+	}
+}
+
+// Collect fetches metrics from NGINX Plus and sends them to the provided channel.
+func (c *NginxPlusCollector) Collect(ch chan<- prometheus.Metric) {
+	c.mutex.Lock() // To protect metrics from concurrent collects
+	defer c.mutex.Unlock()
+
+	stats, err := c.nginxClient.GetStats()
+	if err != nil {
+		c.upMetric.Set(nginxDown)
+		ch <- c.upMetric
+		log.Printf("Error getting stats: %v", err)
+		return
+	}
+
+	c.upMetric.Set(nginxUp)
+	ch <- c.upMetric
+
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["connections_accepted"],
+		prometheus.CounterValue, float64(stats.Connections.Accepted))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["connections_dropped"],
+		prometheus.CounterValue, float64(stats.Connections.Dropped))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["connections_active"],
+		prometheus.GaugeValue, float64(stats.Connections.Active))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["connections_idle"],
+		prometheus.GaugeValue, float64(stats.Connections.Idle))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["http_requests_total"],
+		prometheus.CounterValue, float64(stats.HTTPRequests.Total))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["http_requests_current"],
+		prometheus.GaugeValue, float64(stats.HTTPRequests.Current))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["ssl_handshakes"],
+		prometheus.CounterValue, float64(stats.SSL.Handshakes))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["ssl_handshakes_failed"],
+		prometheus.CounterValue, float64(stats.SSL.HandshakesFailed))
+	ch <- prometheus.MustNewConstMetric(c.totalMetrics["ssl_session_reuses"],
+		prometheus.CounterValue, float64(stats.SSL.SessionReuses))
+
+	for name, zone := range stats.ServerZones {
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["processing"],
+			prometheus.GaugeValue, float64(zone.Processing), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["requests"],
+			prometheus.CounterValue, float64(zone.Requests), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["responses_1xx"],
+			prometheus.CounterValue, float64(zone.Responses.Responses1xx), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["responses_2xx"],
+			prometheus.CounterValue, float64(zone.Responses.Responses2xx), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["responses_3xx"],
+			prometheus.CounterValue, float64(zone.Responses.Responses3xx), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["responses_4xx"],
+			prometheus.CounterValue, float64(zone.Responses.Responses4xx), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["responses_5xx"],
+			prometheus.CounterValue, float64(zone.Responses.Responses5xx), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["discarded"],
+			prometheus.CounterValue, float64(zone.Discarded), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["received"],
+			prometheus.CounterValue, float64(zone.Received), name)
+		ch <- prometheus.MustNewConstMetric(c.serverZoneMetrics["sent"],
+			prometheus.CounterValue, float64(zone.Sent), name)
+	}
+
+	for name, zone := range stats.StreamServerZones {
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["processing"],
+			prometheus.GaugeValue, float64(zone.Processing), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["connections"],
+			prometheus.CounterValue, float64(zone.Connections), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["sessions_2xx"],
+			prometheus.CounterValue, float64(zone.Sessions.Sessions2xx), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["sessions_4xx"],
+			prometheus.CounterValue, float64(zone.Sessions.Sessions4xx), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["sessions_5xx"],
+			prometheus.CounterValue, float64(zone.Sessions.Sessions5xx), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["discarded"],
+			prometheus.CounterValue, float64(zone.Discarded), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["received"],
+			prometheus.CounterValue, float64(zone.Received), name)
+		ch <- prometheus.MustNewConstMetric(c.streamServerZoneMetrics["sent"],
+			prometheus.CounterValue, float64(zone.Sent), name)
+	}
+
+	for name, upstream := range stats.Upstreams {
+		for _, peer := range upstream.Peers {
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["state"],
+				prometheus.GaugeValue, upstreamServerStates[peer.State], name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["active"],
+				prometheus.GaugeValue, float64(peer.Active), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["requests"],
+				prometheus.CounterValue, float64(peer.Requests), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["responses_1xx"],
+				prometheus.CounterValue, float64(peer.Responses.Responses1xx), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["responses_2xx"],
+				prometheus.CounterValue, float64(peer.Responses.Responses2xx), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["responses_3xx"],
+				prometheus.CounterValue, float64(peer.Responses.Responses3xx), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["responses_4xx"],
+				prometheus.CounterValue, float64(peer.Responses.Responses4xx), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["responses_5xx"],
+				prometheus.CounterValue, float64(peer.Responses.Responses5xx), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["sent"],
+				prometheus.CounterValue, float64(peer.Sent), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["received"],
+				prometheus.CounterValue, float64(peer.Received), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["fails"],
+				prometheus.CounterValue, float64(peer.Fails), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["unavail"],
+				prometheus.CounterValue, float64(peer.Unavail), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["header_time"],
+				prometheus.GaugeValue, float64(peer.HeaderTime), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["response_time"],
+				prometheus.GaugeValue, float64(peer.ResponseTime), name, peer.Server)
+
+			if peer.HealthChecks != (plusclient.HealthChecks{}) {
+				ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["health_checks_checks"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Checks), name, peer.Server)
+				ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["health_checks_fails"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Fails), name, peer.Server)
+				ch <- prometheus.MustNewConstMetric(c.upstreamServerMetrics["health_checks_unhealthy"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Unhealthy), name, peer.Server)
+			}
+		}
+		ch <- prometheus.MustNewConstMetric(c.upstreamMetrics["keepalives"],
+			prometheus.GaugeValue, float64(upstream.Keepalives), name)
+		ch <- prometheus.MustNewConstMetric(c.upstreamMetrics["zombies"],
+			prometheus.GaugeValue, float64(upstream.Zombies), name)
+	}
+
+	for name, upstream := range stats.StreamUpstreams {
+		for _, peer := range upstream.Peers {
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["state"],
+				prometheus.GaugeValue, upstreamServerStates[peer.State], name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["active"],
+				prometheus.GaugeValue, float64(peer.Active), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["connections"],
+				prometheus.CounterValue, float64(peer.Connections), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["connect_time"],
+				prometheus.GaugeValue, float64(peer.ConnectTime), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["first_byte_time"],
+				prometheus.GaugeValue, float64(peer.FirstByteTime), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["response_time"],
+				prometheus.GaugeValue, float64(peer.ResponseTime), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["sent"],
+				prometheus.CounterValue, float64(peer.Sent), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["received"],
+				prometheus.CounterValue, float64(peer.Received), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["fails"],
+				prometheus.CounterValue, float64(peer.Fails), name, peer.Server)
+			ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["unavail"],
+				prometheus.CounterValue, float64(peer.Unavail), name, peer.Server)
+			if peer.HealthChecks != (plusclient.HealthChecks{}) {
+				ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["health_checks_checks"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Checks), name, peer.Server)
+				ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["health_checks_fails"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Fails), name, peer.Server)
+				ch <- prometheus.MustNewConstMetric(c.streamUpstreamServerMetrics["health_checks_unhealthy"],
+					prometheus.CounterValue, float64(peer.HealthChecks.Unhealthy), name, peer.Server)
+			}
+		}
+		ch <- prometheus.MustNewConstMetric(c.streamUpstreamMetrics["zombies"],
+			prometheus.GaugeValue, float64(upstream.Zombies), name)
+	}
+}
+
+var upstreamServerStates = map[string]float64{
+	"up":        1.0,
+	"draining":  2.0,
+	"down":      3.0,
+	"unavail":   4.0,
+	"checking":  5.0,
+	"unhealthy": 6.0,
+}
+
+func newServerZoneMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "server_zone", metricName), docString, []string{"server_zone"}, constLabels)
+}
+
+func newStreamServerZoneMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "stream_server_zone", metricName), docString, []string{"server_zone"}, constLabels)
+}
+
+func newUpstreamMetric(namespace string, metricName string, docString string) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "upstream", metricName), docString, []string{"upstream"}, nil)
+}
+
+func newStreamUpstreamMetric(namespace string, metricName string, docString string) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "stream_upstream", metricName), docString, []string{"upstream"}, nil)
+}
+
+func newUpstreamServerMetric(namespace string, metricName string, docString string, constLabels prometheus.Labels) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "upstream_server", metricName), docString, []string{"upstream", "server"}, constLabels)
+}
+
+func newStreamUpstreamServerMetric(namespace string, metricName string, docString string) *prometheus.Desc {
+	return prometheus.NewDesc(prometheus.BuildFQName(namespace, "stream_upstream_server", metricName), docString, []string{"upstream", "server"}, nil)
+}
diff --git a/vendor/github.com/prometheus/client_golang/LICENSE b/vendor/github.com/prometheus/client_golang/LICENSE
new file mode 100644
index 0000000000..261eeb9e9f
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/prometheus/client_golang/NOTICE b/vendor/github.com/prometheus/client_golang/NOTICE
new file mode 100644
index 0000000000..dd878a30ee
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/NOTICE
@@ -0,0 +1,23 @@
+Prometheus instrumentation library for Go applications
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
+
+
+The following components are included in this product:
+
+perks - a fork of https://github.com/bmizerany/perks
+https://github.com/beorn7/perks
+Copyright 2013-2015 Blake Mizerany, Björn Rabenstein
+See https://github.com/beorn7/perks/blob/master/README.md for license details.
+
+Go support for Protocol Buffers - Google's data interchange format
+http://github.com/golang/protobuf/
+Copyright 2010 The Go Authors
+See source code for license details.
+
+Support for streaming Protocol Buffer messages for the Go language (golang).
+https://github.com/matttproud/golang_protobuf_extensions
+Copyright 2013 Matt T. Proud
+Licensed under the Apache License, Version 2.0
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/.gitignore b/vendor/github.com/prometheus/client_golang/prometheus/.gitignore
new file mode 100644
index 0000000000..3460f0346d
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/.gitignore
@@ -0,0 +1 @@
+command-line-arguments.test
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/README.md b/vendor/github.com/prometheus/client_golang/prometheus/README.md
new file mode 100644
index 0000000000..44986bff06
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/README.md
@@ -0,0 +1 @@
+See [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus).
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/collector.go b/vendor/github.com/prometheus/client_golang/prometheus/collector.go
new file mode 100644
index 0000000000..c0d70b2faf
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/collector.go
@@ -0,0 +1,120 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Collector is the interface implemented by anything that can be used by
+// Prometheus to collect metrics. A Collector has to be registered for
+// collection. See Registerer.Register.
+//
+// The stock metrics provided by this package (Gauge, Counter, Summary,
+// Histogram, Untyped) are also Collectors (which only ever collect one metric,
+// namely itself). An implementer of Collector may, however, collect multiple
+// metrics in a coordinated fashion and/or create metrics on the fly. Examples
+// for collectors already implemented in this library are the metric vectors
+// (i.e. collection of multiple instances of the same Metric but with different
+// label values) like GaugeVec or SummaryVec, and the ExpvarCollector.
+type Collector interface {
+	// Describe sends the super-set of all possible descriptors of metrics
+	// collected by this Collector to the provided channel and returns once
+	// the last descriptor has been sent. The sent descriptors fulfill the
+	// consistency and uniqueness requirements described in the Desc
+	// documentation.
+	//
+	// It is valid if one and the same Collector sends duplicate
+	// descriptors. Those duplicates are simply ignored. However, two
+	// different Collectors must not send duplicate descriptors.
+	//
+	// Sending no descriptor at all marks the Collector as “unchecked”,
+	// i.e. no checks will be performed at registration time, and the
+	// Collector may yield any Metric it sees fit in its Collect method.
+	//
+	// This method idempotently sends the same descriptors throughout the
+	// lifetime of the Collector. It may be called concurrently and
+	// therefore must be implemented in a concurrency safe way.
+	//
+	// If a Collector encounters an error while executing this method, it
+	// must send an invalid descriptor (created with NewInvalidDesc) to
+	// signal the error to the registry.
+	Describe(chan<- *Desc)
+	// Collect is called by the Prometheus registry when collecting
+	// metrics. The implementation sends each collected metric via the
+	// provided channel and returns once the last metric has been sent. The
+	// descriptor of each sent metric is one of those returned by Describe
+	// (unless the Collector is unchecked, see above). Returned metrics that
+	// share the same descriptor must differ in their variable label
+	// values.
+	//
+	// This method may be called concurrently and must therefore be
+	// implemented in a concurrency safe way. Blocking occurs at the expense
+	// of total performance of rendering all registered metrics. Ideally,
+	// Collector implementations support concurrent readers.
+	Collect(chan<- Metric)
+}
+
+// DescribeByCollect is a helper to implement the Describe method of a custom
+// Collector. It collects the metrics from the provided Collector and sends
+// their descriptors to the provided channel.
+//
+// If a Collector collects the same metrics throughout its lifetime, its
+// Describe method can simply be implemented as:
+//
+//   func (c customCollector) Describe(ch chan<- *Desc) {
+//   	DescribeByCollect(c, ch)
+//   }
+//
+// However, this will not work if the metrics collected change dynamically over
+// the lifetime of the Collector in a way that their combined set of descriptors
+// changes as well. The shortcut implementation will then violate the contract
+// of the Describe method. If a Collector sometimes collects no metrics at all
+// (for example vectors like CounterVec, GaugeVec, etc., which only collect
+// metrics after a metric with a fully specified label set has been accessed),
+// it might even get registered as an unchecked Collecter (cf. the Register
+// method of the Registerer interface). Hence, only use this shortcut
+// implementation of Describe if you are certain to fulfill the contract.
+//
+// The Collector example demonstrates a use of DescribeByCollect.
+func DescribeByCollect(c Collector, descs chan<- *Desc) {
+	metrics := make(chan Metric)
+	go func() {
+		c.Collect(metrics)
+		close(metrics)
+	}()
+	for m := range metrics {
+		descs <- m.Desc()
+	}
+}
+
+// selfCollector implements Collector for a single Metric so that the Metric
+// collects itself. Add it as an anonymous field to a struct that implements
+// Metric, and call init with the Metric itself as an argument.
+type selfCollector struct {
+	self Metric
+}
+
+// init provides the selfCollector with a reference to the metric it is supposed
+// to collect. It is usually called within the factory function to create a
+// metric. See example.
+func (c *selfCollector) init(self Metric) {
+	c.self = self
+}
+
+// Describe implements Collector.
+func (c *selfCollector) Describe(ch chan<- *Desc) {
+	ch <- c.self.Desc()
+}
+
+// Collect implements Collector.
+func (c *selfCollector) Collect(ch chan<- Metric) {
+	ch <- c.self
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/counter.go b/vendor/github.com/prometheus/client_golang/prometheus/counter.go
new file mode 100644
index 0000000000..d463e36d3e
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/counter.go
@@ -0,0 +1,277 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"math"
+	"sync/atomic"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Counter is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+//
+// A Counter is typically used to count requests served, tasks completed, errors
+// occurred, etc.
+//
+// To create Counter instances, use NewCounter.
+type Counter interface {
+	Metric
+	Collector
+
+	// Inc increments the counter by 1. Use Add to increment it by arbitrary
+	// non-negative values.
+	Inc()
+	// Add adds the given value to the counter. It panics if the value is <
+	// 0.
+	Add(float64)
+}
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts Opts
+
+// NewCounter creates a new Counter based on the provided CounterOpts.
+//
+// The returned implementation tracks the counter value in two separate
+// variables, a float64 and a uint64. The latter is used to track calls of the
+// Inc method and calls of the Add method with a value that can be represented
+// as a uint64. This allows atomic increments of the counter with optimal
+// performance. (It is common to have an Inc call in very hot execution paths.)
+// Both internal tracking values are added up in the Write method. This has to
+// be taken into account when it comes to precision and overflow behavior.
+func NewCounter(opts CounterOpts) Counter {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	)
+	result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
+	result.init(result) // Init self-collection.
+	return result
+}
+
+type counter struct {
+	// valBits contains the bits of the represented float64 value, while
+	// valInt stores values that are exact integers. Both have to go first
+	// in the struct to guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+	valInt  uint64
+
+	selfCollector
+	desc *Desc
+
+	labelPairs []*dto.LabelPair
+}
+
+func (c *counter) Desc() *Desc {
+	return c.desc
+}
+
+func (c *counter) Add(v float64) {
+	if v < 0 {
+		panic(errors.New("counter cannot decrease in value"))
+	}
+	ival := uint64(v)
+	if float64(ival) == v {
+		atomic.AddUint64(&c.valInt, ival)
+		return
+	}
+
+	for {
+		oldBits := atomic.LoadUint64(&c.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (c *counter) Inc() {
+	atomic.AddUint64(&c.valInt, 1)
+}
+
+func (c *counter) Write(out *dto.Metric) error {
+	fval := math.Float64frombits(atomic.LoadUint64(&c.valBits))
+	ival := atomic.LoadUint64(&c.valInt)
+	val := fval + float64(ival)
+
+	return populateMetric(CounterValue, val, c.labelPairs, out)
+}
+
+// CounterVec is a Collector that bundles a set of Counters that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. number of HTTP requests, partitioned by response code and
+// method). Create instances with NewCounterVec.
+type CounterVec struct {
+	*metricVec
+}
+
+// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
+// partitioned by the given label names.
+func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &CounterVec{
+		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			if len(lvs) != len(desc.variableLabels) {
+				panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs))
+			}
+			result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+			result.init(result) // Init self-collection.
+			return result
+		}),
+	}
+}
+
+// GetMetricWithLabelValues returns the Counter for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Counter is created.
+//
+// It is possible to call this method without using the returned Counter to only
+// create the new Counter but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Counter for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Counter from the CounterVec. In that case,
+// the Counter will still exist, but it will not be exported anymore, even if a
+// Counter with the same label values is created later.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// GetMetricWith returns the Counter for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Counter is created. Implications of
+// creating a Counter without using it and keeping the Counter for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (v *CounterVec) WithLabelValues(lvs ...string) Counter {
+	c, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
+func (v *CounterVec) With(labels Labels) Counter {
+	c, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the CounterVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &CounterVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
+}
+
+// CounterFunc is a Counter whose value is determined at collect time by calling a
+// provided function.
+//
+// To create CounterFunc instances, use NewCounterFunc.
+type CounterFunc interface {
+	Metric
+	Collector
+}
+
+// NewCounterFunc creates a new CounterFunc based on the provided
+// CounterOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a CounterFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe. The function should also honor
+// the contract for a Counter (values only go up, not down), but compliance will
+// not be checked.
+func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), CounterValue, function)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/desc.go b/vendor/github.com/prometheus/client_golang/prometheus/desc.go
new file mode 100644
index 0000000000..1d034f871c
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/desc.go
@@ -0,0 +1,184 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/model"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Desc is the descriptor used by every Prometheus Metric. It is essentially
+// the immutable meta-data of a Metric. The normal Metric implementations
+// included in this package manage their Desc under the hood. Users only have to
+// deal with Desc if they use advanced features like the ExpvarCollector or
+// custom Collectors and Metrics.
+//
+// Descriptors registered with the same registry have to fulfill certain
+// consistency and uniqueness criteria if they share the same fully-qualified
+// name: They must have the same help string and the same label names (aka label
+// dimensions) in each, constLabels and variableLabels, but they must differ in
+// the values of the constLabels.
+//
+// Descriptors that share the same fully-qualified names and the same label
+// values of their constLabels are considered equal.
+//
+// Use NewDesc to create new Desc instances.
+type Desc struct {
+	// fqName has been built from Namespace, Subsystem, and Name.
+	fqName string
+	// help provides some helpful information about this metric.
+	help string
+	// constLabelPairs contains precalculated DTO label pairs based on
+	// the constant labels.
+	constLabelPairs []*dto.LabelPair
+	// VariableLabels contains names of labels for which the metric
+	// maintains variable values.
+	variableLabels []string
+	// id is a hash of the values of the ConstLabels and fqName. This
+	// must be unique among all registered descriptors and can therefore be
+	// used as an identifier of the descriptor.
+	id uint64
+	// dimHash is a hash of the label names (preset and variable) and the
+	// Help string. Each Desc with the same fqName must have the same
+	// dimHash.
+	dimHash uint64
+	// err is an error that occurred during construction. It is reported on
+	// registration time.
+	err error
+}
+
+// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
+// and will be reported on registration time. variableLabels and constLabels can
+// be nil if no such labels should be set. fqName must not be empty.
+//
+// variableLabels only contain the label names. Their label values are variable
+// and therefore not part of the Desc. (They are managed within the Metric.)
+//
+// For constLabels, the label values are constant. Therefore, they are fully
+// specified in the Desc. See the Collector example for a usage pattern.
+func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
+	d := &Desc{
+		fqName:         fqName,
+		help:           help,
+		variableLabels: variableLabels,
+	}
+	if !model.IsValidMetricName(model.LabelValue(fqName)) {
+		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
+		return d
+	}
+	// labelValues contains the label values of const labels (in order of
+	// their sorted label names) plus the fqName (at position 0).
+	labelValues := make([]string, 1, len(constLabels)+1)
+	labelValues[0] = fqName
+	labelNames := make([]string, 0, len(constLabels)+len(variableLabels))
+	labelNameSet := map[string]struct{}{}
+	// First add only the const label names and sort them...
+	for labelName := range constLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
+			return d
+		}
+		labelNames = append(labelNames, labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	sort.Strings(labelNames)
+	// ... so that we can now add const label values in the order of their names.
+	for _, labelName := range labelNames {
+		labelValues = append(labelValues, constLabels[labelName])
+	}
+	// Validate the const label values. They can't have a wrong cardinality, so
+	// use in len(labelValues) as expectedNumberOfValues.
+	if err := validateLabelValues(labelValues, len(labelValues)); err != nil {
+		d.err = err
+		return d
+	}
+	// Now add the variable label names, but prefix them with something that
+	// cannot be in a regular label name. That prevents matching the label
+	// dimension with a different mix between preset and variable labels.
+	for _, labelName := range variableLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name for metric %q", labelName, fqName)
+			return d
+		}
+		labelNames = append(labelNames, "$"+labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	if len(labelNames) != len(labelNameSet) {
+		d.err = errors.New("duplicate label names")
+		return d
+	}
+
+	vh := hashNew()
+	for _, val := range labelValues {
+		vh = hashAdd(vh, val)
+		vh = hashAddByte(vh, separatorByte)
+	}
+	d.id = vh
+	// Sort labelNames so that order doesn't matter for the hash.
+	sort.Strings(labelNames)
+	// Now hash together (in this order) the help string and the sorted
+	// label names.
+	lh := hashNew()
+	lh = hashAdd(lh, help)
+	lh = hashAddByte(lh, separatorByte)
+	for _, labelName := range labelNames {
+		lh = hashAdd(lh, labelName)
+		lh = hashAddByte(lh, separatorByte)
+	}
+	d.dimHash = lh
+
+	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
+	for n, v := range constLabels {
+		d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(v),
+		})
+	}
+	sort.Sort(labelPairSorter(d.constLabelPairs))
+	return d
+}
+
+// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the
+// provided error set. If a collector returning such a descriptor is registered,
+// registration will fail with the provided error. NewInvalidDesc can be used by
+// a Collector to signal inability to describe itself.
+func NewInvalidDesc(err error) *Desc {
+	return &Desc{
+		err: err,
+	}
+}
+
+func (d *Desc) String() string {
+	lpStrings := make([]string, 0, len(d.constLabelPairs))
+	for _, lp := range d.constLabelPairs {
+		lpStrings = append(
+			lpStrings,
+			fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()),
+		)
+	}
+	return fmt.Sprintf(
+		"Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}",
+		d.fqName,
+		d.help,
+		strings.Join(lpStrings, ","),
+		d.variableLabels,
+	)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/doc.go b/vendor/github.com/prometheus/client_golang/prometheus/doc.go
new file mode 100644
index 0000000000..5d9525defc
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/doc.go
@@ -0,0 +1,201 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package prometheus is the core instrumentation package. It provides metrics
+// primitives to instrument code for monitoring. It also offers a registry for
+// metrics. Sub-packages allow to expose the registered metrics via HTTP
+// (package promhttp) or push them to a Pushgateway (package push). There is
+// also a sub-package promauto, which provides metrics constructors with
+// automatic registration.
+//
+// All exported functions and methods are safe to be used concurrently unless
+// specified otherwise.
+//
+// A Basic Example
+//
+// As a starting point, a very basic usage example:
+//
+//    package main
+//
+//    import (
+//    	"log"
+//    	"net/http"
+//
+//    	"github.com/prometheus/client_golang/prometheus"
+//    	"github.com/prometheus/client_golang/prometheus/promhttp"
+//    )
+//
+//    var (
+//    	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
+//    		Name: "cpu_temperature_celsius",
+//    		Help: "Current temperature of the CPU.",
+//    	})
+//    	hdFailures = prometheus.NewCounterVec(
+//    		prometheus.CounterOpts{
+//    			Name: "hd_errors_total",
+//    			Help: "Number of hard-disk errors.",
+//    		},
+//    		[]string{"device"},
+//    	)
+//    )
+//
+//    func init() {
+//    	// Metrics have to be registered to be exposed:
+//    	prometheus.MustRegister(cpuTemp)
+//    	prometheus.MustRegister(hdFailures)
+//    }
+//
+//    func main() {
+//    	cpuTemp.Set(65.3)
+//    	hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc()
+//
+//    	// The Handler function provides a default handler to expose metrics
+//    	// via an HTTP server. "/metrics" is the usual endpoint for that.
+//    	http.Handle("/metrics", promhttp.Handler())
+//    	log.Fatal(http.ListenAndServe(":8080", nil))
+//    }
+//
+//
+// This is a complete program that exports two metrics, a Gauge and a Counter,
+// the latter with a label attached to turn it into a (one-dimensional) vector.
+//
+// Metrics
+//
+// The number of exported identifiers in this package might appear a bit
+// overwhelming. However, in addition to the basic plumbing shown in the example
+// above, you only need to understand the different metric types and their
+// vector versions for basic usage. Furthermore, if you are not concerned with
+// fine-grained control of when and how to register metrics with the registry,
+// have a look at the promauto package, which will effectively allow you to
+// ignore registration altogether in simple cases.
+//
+// Above, you have already touched the Counter and the Gauge. There are two more
+// advanced metric types: the Summary and Histogram. A more thorough description
+// of those four metric types can be found in the Prometheus docs:
+// https://prometheus.io/docs/concepts/metric_types/
+//
+// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the
+// Prometheus server not to assume anything about its type.
+//
+// In addition to the fundamental metric types Gauge, Counter, Summary,
+// Histogram, and Untyped, a very important part of the Prometheus data model is
+// the partitioning of samples along dimensions called labels, which results in
+// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
+// HistogramVec, and UntypedVec.
+//
+// While only the fundamental metric types implement the Metric interface, both
+// the metrics and their vector versions implement the Collector interface. A
+// Collector manages the collection of a number of Metrics, but for convenience,
+// a Metric can also “collect itself”. Note that Gauge, Counter, Summary,
+// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec,
+// SummaryVec, HistogramVec, and UntypedVec are not.
+//
+// To create instances of Metrics and their vector versions, you need a suitable
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
+// UntypedOpts.
+//
+// Custom Collectors and constant Metrics
+//
+// While you could create your own implementations of Metric, most likely you
+// will only ever implement the Collector interface on your own. At a first
+// glance, a custom Collector seems handy to bundle Metrics for common
+// registration (with the prime example of the different metric vectors above,
+// which bundle all the metrics of the same name but with different labels).
+//
+// There is a more involved use case, too: If you already have metrics
+// available, created outside of the Prometheus context, you don't need the
+// interface of the various Metric types. You essentially want to mirror the
+// existing numbers into Prometheus Metrics during collection. An own
+// implementation of the Collector interface is perfect for that. You can create
+// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
+// NewConstSummary (and their respective Must… versions). That will happen in
+// the Collect method. The Describe method has to return separate Desc
+// instances, representative of the “throw-away” metrics to be created later.
+// NewDesc comes in handy to create those Desc instances. Alternatively, you
+// could return no Desc at all, which will marke the Collector “unchecked”.  No
+// checks are porformed at registration time, but metric consistency will still
+// be ensured at scrape time, i.e. any inconsistencies will lead to scrape
+// errors. Thus, with unchecked Collectors, the responsibility to not collect
+// metrics that lead to inconsistencies in the total scrape result lies with the
+// implementer of the Collector. While this is not a desirable state, it is
+// sometimes necessary. The typical use case is a situatios where the exact
+// metrics to be returned by a Collector cannot be predicted at registration
+// time, but the implementer has sufficient knowledge of the whole system to
+// guarantee metric consistency.
+//
+// The Collector example illustrates the use case. You can also look at the
+// source code of the processCollector (mirroring process metrics), the
+// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar
+// metrics) as examples that are used in this package itself.
+//
+// If you just need to call a function to get a single float value to collect as
+// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting
+// shortcuts.
+//
+// Advanced Uses of the Registry
+//
+// While MustRegister is the by far most common way of registering a Collector,
+// sometimes you might want to handle the errors the registration might cause.
+// As suggested by the name, MustRegister panics if an error occurs. With the
+// Register function, the error is returned and can be handled.
+//
+// An error is returned if the registered Collector is incompatible or
+// inconsistent with already registered metrics. The registry aims for
+// consistency of the collected metrics according to the Prometheus data model.
+// Inconsistencies are ideally detected at registration time, not at collect
+// time. The former will usually be detected at start-up time of a program,
+// while the latter will only happen at scrape time, possibly not even on the
+// first scrape if the inconsistency only becomes relevant later. That is the
+// main reason why a Collector and a Metric have to describe themselves to the
+// registry.
+//
+// So far, everything we did operated on the so-called default registry, as it
+// can be found in the global DefaultRegisterer variable. With NewRegistry, you
+// can create a custom registry, or you can even implement the Registerer or
+// Gatherer interfaces yourself. The methods Register and Unregister work in the
+// same way on a custom registry as the global functions Register and Unregister
+// on the default registry.
+//
+// There are a number of uses for custom registries: You can use registries with
+// special properties, see NewPedanticRegistry. You can avoid global state, as
+// it is imposed by the DefaultRegisterer. You can use multiple registries at
+// the same time to expose different metrics in different ways.  You can use
+// separate registries for testing purposes.
+//
+// Also note that the DefaultRegisterer comes registered with a Collector for Go
+// runtime metrics (via NewGoCollector) and a Collector for process metrics (via
+// NewProcessCollector). With a custom registry, you are in control and decide
+// yourself about the Collectors to register.
+//
+// HTTP Exposition
+//
+// The Registry implements the Gatherer interface. The caller of the Gather
+// method can then expose the gathered metrics in some way. Usually, the metrics
+// are served via HTTP on the /metrics endpoint. That's happening in the example
+// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
+// (The top-level functions in the prometheus package are deprecated.)
+//
+// Pushing to the Pushgateway
+//
+// Function for pushing to the Pushgateway can be found in the push sub-package.
+//
+// Graphite Bridge
+//
+// Functions and examples to push metrics from a Gatherer to Graphite can be
+// found in the graphite sub-package.
+//
+// Other Means of Exposition
+//
+// More ways of exposing metrics can easily be added by following the approaches
+// of the existing implementations.
+package prometheus
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go
new file mode 100644
index 0000000000..18a99d5faa
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go
@@ -0,0 +1,119 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"encoding/json"
+	"expvar"
+)
+
+type expvarCollector struct {
+	exports map[string]*Desc
+}
+
+// NewExpvarCollector returns a newly allocated expvar Collector that still has
+// to be registered with a Prometheus registry.
+//
+// An expvar Collector collects metrics from the expvar interface. It provides a
+// quick way to expose numeric values that are already exported via expvar as
+// Prometheus metrics. Note that the data models of expvar and Prometheus are
+// fundamentally different, and that the expvar Collector is inherently slower
+// than native Prometheus metrics. Thus, the expvar Collector is probably great
+// for experiments and prototying, but you should seriously consider a more
+// direct implementation of Prometheus metrics for monitoring production
+// systems.
+//
+// The exports map has the following meaning:
+//
+// The keys in the map correspond to expvar keys, i.e. for every expvar key you
+// want to export as Prometheus metric, you need an entry in the exports
+// map. The descriptor mapped to each key describes how to export the expvar
+// value. It defines the name and the help string of the Prometheus metric
+// proxying the expvar value. The type will always be Untyped.
+//
+// For descriptors without variable labels, the expvar value must be a number or
+// a bool. The number is then directly exported as the Prometheus sample
+// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values
+// that are not numbers or bools are silently ignored.
+//
+// If the descriptor has one variable label, the expvar value must be an expvar
+// map. The keys in the expvar map become the various values of the one
+// Prometheus label. The values in the expvar map must be numbers or bools again
+// as above.
+//
+// For descriptors with more than one variable label, the expvar must be a
+// nested expvar map, i.e. where the values of the topmost map are maps again
+// etc. until a depth is reached that corresponds to the number of labels. The
+// leaves of that structure must be numbers or bools as above to serve as the
+// sample values.
+//
+// Anything that does not fit into the scheme above is silently ignored.
+func NewExpvarCollector(exports map[string]*Desc) Collector {
+	return &expvarCollector{
+		exports: exports,
+	}
+}
+
+// Describe implements Collector.
+func (e *expvarCollector) Describe(ch chan<- *Desc) {
+	for _, desc := range e.exports {
+		ch <- desc
+	}
+}
+
+// Collect implements Collector.
+func (e *expvarCollector) Collect(ch chan<- Metric) {
+	for name, desc := range e.exports {
+		var m Metric
+		expVar := expvar.Get(name)
+		if expVar == nil {
+			continue
+		}
+		var v interface{}
+		labels := make([]string, len(desc.variableLabels))
+		if err := json.Unmarshal([]byte(expVar.String()), &v); err != nil {
+			ch <- NewInvalidMetric(desc, err)
+			continue
+		}
+		var processValue func(v interface{}, i int)
+		processValue = func(v interface{}, i int) {
+			if i >= len(labels) {
+				copiedLabels := append(make([]string, 0, len(labels)), labels...)
+				switch v := v.(type) {
+				case float64:
+					m = MustNewConstMetric(desc, UntypedValue, v, copiedLabels...)
+				case bool:
+					if v {
+						m = MustNewConstMetric(desc, UntypedValue, 1, copiedLabels...)
+					} else {
+						m = MustNewConstMetric(desc, UntypedValue, 0, copiedLabels...)
+					}
+				default:
+					return
+				}
+				ch <- m
+				return
+			}
+			vm, ok := v.(map[string]interface{})
+			if !ok {
+				return
+			}
+			for lv, val := range vm {
+				labels[i] = lv
+				processValue(val, i+1)
+			}
+		}
+		processValue(v, 0)
+	}
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/fnv.go b/vendor/github.com/prometheus/client_golang/prometheus/fnv.go
new file mode 100644
index 0000000000..3d383a735c
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/fnv.go
@@ -0,0 +1,42 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Inline and byte-free variant of hash/fnv's fnv64a.
+
+const (
+	offset64 = 14695981039346656037
+	prime64  = 1099511628211
+)
+
+// hashNew initializies a new fnv64a hash value.
+func hashNew() uint64 {
+	return offset64
+}
+
+// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
+func hashAdd(h uint64, s string) uint64 {
+	for i := 0; i < len(s); i++ {
+		h ^= uint64(s[i])
+		h *= prime64
+	}
+	return h
+}
+
+// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
+func hashAddByte(h uint64, b byte) uint64 {
+	h ^= uint64(b)
+	h *= prime64
+	return h
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
new file mode 100644
index 0000000000..71d406bd92
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
@@ -0,0 +1,286 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"math"
+	"sync/atomic"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Gauge is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// A Gauge is typically used for measured values like temperatures or current
+// memory usage, but also "counts" that can go up and down, like the number of
+// running goroutines.
+//
+// To create Gauge instances, use NewGauge.
+type Gauge interface {
+	Metric
+	Collector
+
+	// Set sets the Gauge to an arbitrary value.
+	Set(float64)
+	// Inc increments the Gauge by 1. Use Add to increment it by arbitrary
+	// values.
+	Inc()
+	// Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
+	// values.
+	Dec()
+	// Add adds the given value to the Gauge. (The value can be negative,
+	// resulting in a decrease of the Gauge.)
+	Add(float64)
+	// Sub subtracts the given value from the Gauge. (The value can be
+	// negative, resulting in an increase of the Gauge.)
+	Sub(float64)
+
+	// SetToCurrentTime sets the Gauge to the current Unix time in seconds.
+	SetToCurrentTime()
+}
+
+// GaugeOpts is an alias for Opts. See there for doc comments.
+type GaugeOpts Opts
+
+// NewGauge creates a new Gauge based on the provided GaugeOpts.
+//
+// The returned implementation is optimized for a fast Set method. If you have a
+// choice for managing the value of a Gauge via Set vs. Inc/Dec/Add/Sub, pick
+// the former. For example, the Inc method of the returned Gauge is slower than
+// the Inc method of a Counter returned by NewCounter. This matches the typical
+// scenarios for Gauges and Counters, where the former tends to be Set-heavy and
+// the latter Inc-heavy.
+func NewGauge(opts GaugeOpts) Gauge {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	)
+	result := &gauge{desc: desc, labelPairs: desc.constLabelPairs}
+	result.init(result) // Init self-collection.
+	return result
+}
+
+type gauge struct {
+	// valBits contains the bits of the represented float64 value. It has
+	// to go first in the struct to guarantee alignment for atomic
+	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+
+	selfCollector
+
+	desc       *Desc
+	labelPairs []*dto.LabelPair
+}
+
+func (g *gauge) Desc() *Desc {
+	return g.desc
+}
+
+func (g *gauge) Set(val float64) {
+	atomic.StoreUint64(&g.valBits, math.Float64bits(val))
+}
+
+func (g *gauge) SetToCurrentTime() {
+	g.Set(float64(time.Now().UnixNano()) / 1e9)
+}
+
+func (g *gauge) Inc() {
+	g.Add(1)
+}
+
+func (g *gauge) Dec() {
+	g.Add(-1)
+}
+
+func (g *gauge) Add(val float64) {
+	for {
+		oldBits := atomic.LoadUint64(&g.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
+		if atomic.CompareAndSwapUint64(&g.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (g *gauge) Sub(val float64) {
+	g.Add(val * -1)
+}
+
+func (g *gauge) Write(out *dto.Metric) error {
+	val := math.Float64frombits(atomic.LoadUint64(&g.valBits))
+	return populateMetric(GaugeValue, val, g.labelPairs, out)
+}
+
+// GaugeVec is a Collector that bundles a set of Gauges that all share the same
+// Desc, but have different values for their variable labels. This is used if
+// you want to count the same thing partitioned by various dimensions
+// (e.g. number of operations queued, partitioned by user and operation
+// type). Create instances with NewGaugeVec.
+type GaugeVec struct {
+	*metricVec
+}
+
+// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
+// partitioned by the given label names.
+func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &GaugeVec{
+		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			if len(lvs) != len(desc.variableLabels) {
+				panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs))
+			}
+			result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+			result.init(result) // Init self-collection.
+			return result
+		}),
+	}
+}
+
+// GetMetricWithLabelValues returns the Gauge for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Gauge is created.
+//
+// It is possible to call this method without using the returned Gauge to only
+// create the new Gauge but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Gauge for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Gauge from the GaugeVec. In that case, the
+// Gauge will still exist, but it will not be exported anymore, even if a
+// Gauge with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// GetMetricWith returns the Gauge for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Gauge is created. Implications of
+// creating a Gauge without using it and keeping the Gauge for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (v *GaugeVec) WithLabelValues(lvs ...string) Gauge {
+	g, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return g
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
+func (v *GaugeVec) With(labels Labels) Gauge {
+	g, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return g
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the GaugeVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *GaugeVec) CurryWith(labels Labels) (*GaugeVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &GaugeVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *GaugeVec) MustCurryWith(labels Labels) *GaugeVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
+}
+
+// GaugeFunc is a Gauge whose value is determined at collect time by calling a
+// provided function.
+//
+// To create GaugeFunc instances, use NewGaugeFunc.
+type GaugeFunc interface {
+	Metric
+	Collector
+}
+
+// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The
+// value reported is determined by calling the given function from within the
+// Write method. Take into account that metric collection may happen
+// concurrently. If that results in concurrent calls to Write, like in the case
+// where a GaugeFunc is directly registered with Prometheus, the provided
+// function must be concurrency-safe.
+func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), GaugeValue, function)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go
new file mode 100644
index 0000000000..ba3b9333ed
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go
@@ -0,0 +1,301 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"runtime"
+	"runtime/debug"
+	"time"
+)
+
+type goCollector struct {
+	goroutinesDesc *Desc
+	threadsDesc    *Desc
+	gcDesc         *Desc
+	goInfoDesc     *Desc
+
+	// metrics to describe and collect
+	metrics memStatsMetrics
+}
+
+// NewGoCollector returns a collector which exports metrics about the current Go
+// process. This includes memory stats. To collect those, runtime.ReadMemStats
+// is called. This causes a stop-the-world, which is very short with Go1.9+
+// (~25µs). However, with older Go versions, the stop-the-world duration depends
+// on the heap size and can be quite significant (~1.7 ms/GiB as per
+// https://go-review.googlesource.com/c/go/+/34937).
+func NewGoCollector() Collector {
+	return &goCollector{
+		goroutinesDesc: NewDesc(
+			"go_goroutines",
+			"Number of goroutines that currently exist.",
+			nil, nil),
+		threadsDesc: NewDesc(
+			"go_threads",
+			"Number of OS threads created.",
+			nil, nil),
+		gcDesc: NewDesc(
+			"go_gc_duration_seconds",
+			"A summary of the GC invocation durations.",
+			nil, nil),
+		goInfoDesc: NewDesc(
+			"go_info",
+			"Information about the Go environment.",
+			nil, Labels{"version": runtime.Version()}),
+		metrics: memStatsMetrics{
+			{
+				desc: NewDesc(
+					memstatNamespace("alloc_bytes"),
+					"Number of bytes allocated and still in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("alloc_bytes_total"),
+					"Total number of bytes allocated, even if freed.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("sys_bytes"),
+					"Number of bytes obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("lookups_total"),
+					"Total number of pointer lookups.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mallocs_total"),
+					"Total number of mallocs.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("frees_total"),
+					"Total number of frees.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Frees) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_alloc_bytes"),
+					"Number of heap bytes allocated and still in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_sys_bytes"),
+					"Number of heap bytes obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_idle_bytes"),
+					"Number of heap bytes waiting to be used.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_inuse_bytes"),
+					"Number of heap bytes that are in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_released_bytes"),
+					"Number of heap bytes released to OS.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_objects"),
+					"Number of allocated objects.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("stack_inuse_bytes"),
+					"Number of bytes in use by the stack allocator.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("stack_sys_bytes"),
+					"Number of bytes obtained from system for stack allocator.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mspan_inuse_bytes"),
+					"Number of bytes in use by mspan structures.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mspan_sys_bytes"),
+					"Number of bytes used for mspan structures obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mcache_inuse_bytes"),
+					"Number of bytes in use by mcache structures.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mcache_sys_bytes"),
+					"Number of bytes used for mcache structures obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("buck_hash_sys_bytes"),
+					"Number of bytes used by the profiling bucket hash table.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("gc_sys_bytes"),
+					"Number of bytes used for garbage collection system metadata.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("other_sys_bytes"),
+					"Number of bytes used for other system allocations.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("next_gc_bytes"),
+					"Number of heap bytes when next garbage collection will take place.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("last_gc_time_seconds"),
+					"Number of seconds since 1970 of last garbage collection.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("gc_cpu_fraction"),
+					"The fraction of this program's available CPU time used by the GC since the program started.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction },
+				valType: GaugeValue,
+			},
+		},
+	}
+}
+
+func memstatNamespace(s string) string {
+	return fmt.Sprintf("go_memstats_%s", s)
+}
+
+// Describe returns all descriptions of the collector.
+func (c *goCollector) Describe(ch chan<- *Desc) {
+	ch <- c.goroutinesDesc
+	ch <- c.threadsDesc
+	ch <- c.gcDesc
+	ch <- c.goInfoDesc
+	for _, i := range c.metrics {
+		ch <- i.desc
+	}
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *goCollector) Collect(ch chan<- Metric) {
+	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
+	n, _ := runtime.ThreadCreateProfile(nil)
+	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
+
+	var stats debug.GCStats
+	stats.PauseQuantiles = make([]time.Duration, 5)
+	debug.ReadGCStats(&stats)
+
+	quantiles := make(map[float64]float64)
+	for idx, pq := range stats.PauseQuantiles[1:] {
+		quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds()
+	}
+	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
+	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles)
+
+	ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1)
+
+	ms := &runtime.MemStats{}
+	runtime.ReadMemStats(ms)
+	for _, i := range c.metrics {
+		ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms))
+	}
+}
+
+// memStatsMetrics provide description, value, and value type for memstat metrics.
+type memStatsMetrics []struct {
+	desc    *Desc
+	eval    func(*runtime.MemStats) float64
+	valType ValueType
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go
new file mode 100644
index 0000000000..f88da707bc
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go
@@ -0,0 +1,614 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"math"
+	"runtime"
+	"sort"
+	"sync"
+	"sync/atomic"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// A Histogram counts individual observations from an event or sample stream in
+// configurable buckets. Similar to a summary, it also provides a sum of
+// observations and an observation count.
+//
+// On the Prometheus server, quantiles can be calculated from a Histogram using
+// the histogram_quantile function in the query language.
+//
+// Note that Histograms, in contrast to Summaries, can be aggregated with the
+// Prometheus query language (see the documentation for detailed
+// procedures). However, Histograms require the user to pre-define suitable
+// buckets, and they are in general less accurate. The Observe method of a
+// Histogram has a very low performance overhead in comparison with the Observe
+// method of a Summary.
+//
+// To create Histogram instances, use NewHistogram.
+type Histogram interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the histogram.
+	Observe(float64)
+}
+
+// bucketLabel is used for the label that defines the upper bound of a
+// bucket of a histogram ("le" -> "less or equal").
+const bucketLabel = "le"
+
+// DefBuckets are the default Histogram buckets. The default buckets are
+// tailored to broadly measure the response time (in seconds) of a network
+// service. Most likely, however, you will be required to define buckets
+// customized to your use case.
+var (
+	DefBuckets = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
+
+	errBucketLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in histograms", bucketLabel,
+	)
+)
+
+// LinearBuckets creates 'count' buckets, each 'width' wide, where the lowest
+// bucket has an upper bound of 'start'. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is zero or negative.
+func LinearBuckets(start, width float64, count int) []float64 {
+	if count < 1 {
+		panic("LinearBuckets needs a positive count")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start += width
+	}
+	return buckets
+}
+
+// ExponentialBuckets creates 'count' buckets, where the lowest bucket has an
+// upper bound of 'start' and each following bucket's upper bound is 'factor'
+// times the previous bucket's upper bound. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is 0 or negative, if 'start' is 0 or negative,
+// or if 'factor' is less than or equal 1.
+func ExponentialBuckets(start, factor float64, count int) []float64 {
+	if count < 1 {
+		panic("ExponentialBuckets needs a positive count")
+	}
+	if start <= 0 {
+		panic("ExponentialBuckets needs a positive start value")
+	}
+	if factor <= 1 {
+		panic("ExponentialBuckets needs a factor greater than 1")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start *= factor
+	}
+	return buckets
+}
+
+// HistogramOpts bundles the options for creating a Histogram metric. It is
+// mandatory to set Name to a non-empty string. All other fields are optional
+// and can safely be left at their zero value, although it is strongly
+// encouraged to set a Help string.
+type HistogramOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Histogram (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Histogram must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Histogram.
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
+	// with the same fully-qualified name must have the same label names in
+	// their ConstLabels.
+	//
+	// ConstLabels are only used rarely. In particular, do not use them to
+	// attach the same labels to all your metrics. Those use cases are
+	// better covered by target labels set by the scraping Prometheus
+	// server, or by one specific metric (e.g. a build_info or a
+	// machine_role metric). See also
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
+	ConstLabels Labels
+
+	// Buckets defines the buckets into which observations are counted. Each
+	// element in the slice is the upper inclusive bound of a bucket. The
+	// values must be sorted in strictly increasing order. There is no need
+	// to add a highest bucket with +Inf bound, it will be added
+	// implicitly. The default value is DefBuckets.
+	Buckets []float64
+}
+
+// NewHistogram creates a new Histogram based on the provided HistogramOpts. It
+// panics if the buckets in HistogramOpts are not in strictly increasing order.
+func NewHistogram(opts HistogramOpts) Histogram {
+	return newHistogram(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues))
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+
+	if len(opts.Buckets) == 0 {
+		opts.Buckets = DefBuckets
+	}
+
+	h := &histogram{
+		desc:        desc,
+		upperBounds: opts.Buckets,
+		labelPairs:  makeLabelPairs(desc, labelValues),
+		counts:      [2]*histogramCounts{&histogramCounts{}, &histogramCounts{}},
+	}
+	for i, upperBound := range h.upperBounds {
+		if i < len(h.upperBounds)-1 {
+			if upperBound >= h.upperBounds[i+1] {
+				panic(fmt.Errorf(
+					"histogram buckets must be in increasing order: %f >= %f",
+					upperBound, h.upperBounds[i+1],
+				))
+			}
+		} else {
+			if math.IsInf(upperBound, +1) {
+				// The +Inf bucket is implicit. Remove it here.
+				h.upperBounds = h.upperBounds[:i]
+			}
+		}
+	}
+	// Finally we know the final length of h.upperBounds and can make counts
+	// for both states:
+	h.counts[0].buckets = make([]uint64, len(h.upperBounds))
+	h.counts[1].buckets = make([]uint64, len(h.upperBounds))
+
+	h.init(h) // Init self-collection.
+	return h
+}
+
+type histogramCounts struct {
+	// sumBits contains the bits of the float64 representing the sum of all
+	// observations. sumBits and count have to go first in the struct to
+	// guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	sumBits uint64
+	count   uint64
+	buckets []uint64
+}
+
+type histogram struct {
+	// countAndHotIdx is a complicated one. For lock-free yet atomic
+	// observations, we need to save the total count of observations again,
+	// combined with the index of the currently-hot counts struct, so that
+	// we can perform the operation on both values atomically. The least
+	// significant bit defines the hot counts struct. The remaining 63 bits
+	// represent the total count of observations. This happens under the
+	// assumption that the 63bit count will never overflow. Rationale: An
+	// observations takes about 30ns. Let's assume it could happen in
+	// 10ns. Overflowing the counter will then take at least (2^63)*10ns,
+	// which is about 3000 years.
+	//
+	// This has to be first in the struct for 64bit alignment. See
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	countAndHotIdx uint64
+
+	selfCollector
+	desc     *Desc
+	writeMtx sync.Mutex // Only used in the Write method.
+
+	upperBounds []float64
+
+	// Two counts, one is "hot" for lock-free observations, the other is
+	// "cold" for writing out a dto.Metric. It has to be an array of
+	// pointers to guarantee 64bit alignment of the histogramCounts, see
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG.
+	counts [2]*histogramCounts
+	hotIdx int // Index of currently-hot counts. Only used within Write.
+
+	labelPairs []*dto.LabelPair
+}
+
+func (h *histogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *histogram) Observe(v float64) {
+	// TODO(beorn7): For small numbers of buckets (<30), a linear search is
+	// slightly faster than the binary search. If we really care, we could
+	// switch from one search strategy to the other depending on the number
+	// of buckets.
+	//
+	// Microbenchmarks (BenchmarkHistogramNoLabels):
+	// 11 buckets: 38.3 ns/op linear - binary 48.7 ns/op
+	// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
+	// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
+	i := sort.SearchFloat64s(h.upperBounds, v)
+
+	// We increment h.countAndHotIdx by 2 so that the counter in the upper
+	// 63 bits gets incremented by 1. At the same time, we get the new value
+	// back, which we can use to find the currently-hot counts.
+	n := atomic.AddUint64(&h.countAndHotIdx, 2)
+	hotCounts := h.counts[n%2]
+
+	if i < len(h.upperBounds) {
+		atomic.AddUint64(&hotCounts.buckets[i], 1)
+	}
+	for {
+		oldBits := atomic.LoadUint64(&hotCounts.sumBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
+			break
+		}
+	}
+	// Increment count last as we take it as a signal that the observation
+	// is complete.
+	atomic.AddUint64(&hotCounts.count, 1)
+}
+
+func (h *histogram) Write(out *dto.Metric) error {
+	var (
+		his                   = &dto.Histogram{}
+		buckets               = make([]*dto.Bucket, len(h.upperBounds))
+		hotCounts, coldCounts *histogramCounts
+		count                 uint64
+	)
+
+	// For simplicity, we mutex the rest of this method. It is not in the
+	// hot path, i.e.  Observe is called much more often than Write. The
+	// complication of making Write lock-free isn't worth it.
+	h.writeMtx.Lock()
+	defer h.writeMtx.Unlock()
+
+	// This is a bit arcane, which is why the following spells out this if
+	// clause in English:
+	//
+	// If the currently-hot counts struct is #0, we atomically increment
+	// h.countAndHotIdx by 1 so that from now on Observe will use the counts
+	// struct #1. Furthermore, the atomic increment gives us the new value,
+	// which, in its most significant 63 bits, tells us the count of
+	// observations done so far up to and including currently ongoing
+	// observations still using the counts struct just changed from hot to
+	// cold. To have a normal uint64 for the count, we bitshift by 1 and
+	// save the result in count. We also set h.hotIdx to 1 for the next
+	// Write call, and we will refer to counts #1 as hotCounts and to counts
+	// #0 as coldCounts.
+	//
+	// If the currently-hot counts struct is #1, we do the corresponding
+	// things the other way round. We have to _decrement_ h.countAndHotIdx
+	// (which is a bit arcane in itself, as we have to express -1 with an
+	// unsigned int...).
+	if h.hotIdx == 0 {
+		count = atomic.AddUint64(&h.countAndHotIdx, 1) >> 1
+		h.hotIdx = 1
+		hotCounts = h.counts[1]
+		coldCounts = h.counts[0]
+	} else {
+		count = atomic.AddUint64(&h.countAndHotIdx, ^uint64(0)) >> 1 // Decrement.
+		h.hotIdx = 0
+		hotCounts = h.counts[0]
+		coldCounts = h.counts[1]
+	}
+
+	// Now we have to wait for the now-declared-cold counts to actually cool
+	// down, i.e. wait for all observations still using it to finish. That's
+	// the case once the count in the cold counts struct is the same as the
+	// one atomically retrieved from the upper 63bits of h.countAndHotIdx.
+	for {
+		if count == atomic.LoadUint64(&coldCounts.count) {
+			break
+		}
+		runtime.Gosched() // Let observations get work done.
+	}
+
+	his.SampleCount = proto.Uint64(count)
+	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&coldCounts.sumBits)))
+	var cumCount uint64
+	for i, upperBound := range h.upperBounds {
+		cumCount += atomic.LoadUint64(&coldCounts.buckets[i])
+		buckets[i] = &dto.Bucket{
+			CumulativeCount: proto.Uint64(cumCount),
+			UpperBound:      proto.Float64(upperBound),
+		}
+	}
+
+	his.Bucket = buckets
+	out.Histogram = his
+	out.Label = h.labelPairs
+
+	// Finally add all the cold counts to the new hot counts and reset the cold counts.
+	atomic.AddUint64(&hotCounts.count, count)
+	atomic.StoreUint64(&coldCounts.count, 0)
+	for {
+		oldBits := atomic.LoadUint64(&hotCounts.sumBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + his.GetSampleSum())
+		if atomic.CompareAndSwapUint64(&hotCounts.sumBits, oldBits, newBits) {
+			atomic.StoreUint64(&coldCounts.sumBits, 0)
+			break
+		}
+	}
+	for i := range h.upperBounds {
+		atomic.AddUint64(&hotCounts.buckets[i], atomic.LoadUint64(&coldCounts.buckets[i]))
+		atomic.StoreUint64(&coldCounts.buckets[i], 0)
+	}
+	return nil
+}
+
+// HistogramVec is a Collector that bundles a set of Histograms that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewHistogramVec.
+type HistogramVec struct {
+	*metricVec
+}
+
+// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
+// partitioned by the given label names.
+func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &HistogramVec{
+		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newHistogram(desc, opts, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues returns the Histogram for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Histogram is created.
+//
+// It is possible to call this method without using the returned Histogram to only
+// create the new Histogram but leave it at its starting value, a Histogram without
+// any observations.
+//
+// Keeping the Histogram for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Histogram from the HistogramVec. In that case, the
+// Histogram will still exist, but it will not be exported anymore, even if a
+// Histogram with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Observer), err
+	}
+	return nil, err
+}
+
+// GetMetricWith returns the Histogram for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Histogram is created. Implications of
+// creating a Histogram without using it and keeping the Histogram for later use
+// are the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
+	if metric != nil {
+		return metric.(Observer), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (v *HistogramVec) WithLabelValues(lvs ...string) Observer {
+	h, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return h
+}
+
+// With works as GetMetricWith but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (v *HistogramVec) With(labels Labels) Observer {
+	h, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return h
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the HistogramVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *HistogramVec) CurryWith(labels Labels) (ObserverVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &HistogramVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *HistogramVec) MustCurryWith(labels Labels) ObserverVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
+}
+
+type constHistogram struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	buckets    map[float64]uint64
+	labelPairs []*dto.LabelPair
+}
+
+func (h *constHistogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *constHistogram) Write(out *dto.Metric) error {
+	his := &dto.Histogram{}
+	buckets := make([]*dto.Bucket, 0, len(h.buckets))
+
+	his.SampleCount = proto.Uint64(h.count)
+	his.SampleSum = proto.Float64(h.sum)
+
+	for upperBound, count := range h.buckets {
+		buckets = append(buckets, &dto.Bucket{
+			CumulativeCount: proto.Uint64(count),
+			UpperBound:      proto.Float64(upperBound),
+		})
+	}
+
+	if len(buckets) > 0 {
+		sort.Sort(buckSort(buckets))
+	}
+	his.Bucket = buckets
+
+	out.Histogram = his
+	out.Label = h.labelPairs
+
+	return nil
+}
+
+// NewConstHistogram returns a metric representing a Prometheus histogram with
+// fixed values for the count, sum, and bucket counts. As those parameters
+// cannot be changed, the returned value does not implement the Histogram
+// interface (but only the Metric interface). Users of this package will not
+// have much use for it in regular operations. However, when implementing custom
+// Collectors, it is useful as a throw-away metric that is generated on the fly
+// to send it to Prometheus in the Collect method.
+//
+// buckets is a map of upper bounds to cumulative counts, excluding the +Inf
+// bucket.
+//
+// NewConstHistogram returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc or if Desc is invalid.
+func NewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
+		return nil, err
+	}
+	return &constHistogram{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		buckets:    buckets,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstHistogram is a version of NewConstHistogram that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstHistogram(desc, count, sum, buckets, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type buckSort []*dto.Bucket
+
+func (s buckSort) Len() int {
+	return len(s)
+}
+
+func (s buckSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s buckSort) Less(i, j int) bool {
+	return s[i].GetUpperBound() < s[j].GetUpperBound()
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/http.go b/vendor/github.com/prometheus/client_golang/prometheus/http.go
new file mode 100644
index 0000000000..9f0875bfc8
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/http.go
@@ -0,0 +1,504 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bufio"
+	"compress/gzip"
+	"io"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/prometheus/common/expfmt"
+)
+
+// TODO(beorn7): Remove this whole file. It is a partial mirror of
+// promhttp/http.go (to avoid circular import chains) where everything HTTP
+// related should live. The functions here are just for avoiding
+// breakage. Everything is deprecated.
+
+const (
+	contentTypeHeader     = "Content-Type"
+	contentLengthHeader   = "Content-Length"
+	contentEncodingHeader = "Content-Encoding"
+	acceptEncodingHeader  = "Accept-Encoding"
+)
+
+var gzipPool = sync.Pool{
+	New: func() interface{} {
+		return gzip.NewWriter(nil)
+	},
+}
+
+// Handler returns an HTTP handler for the DefaultGatherer. It is
+// already instrumented with InstrumentHandler (using "prometheus" as handler
+// name).
+//
+// Deprecated: Please note the issues described in the doc comment of
+// InstrumentHandler. You might want to consider using promhttp.Handler instead.
+func Handler() http.Handler {
+	return InstrumentHandler("prometheus", UninstrumentedHandler())
+}
+
+// UninstrumentedHandler returns an HTTP handler for the DefaultGatherer.
+//
+// Deprecated: Use promhttp.HandlerFor(DefaultGatherer, promhttp.HandlerOpts{})
+// instead. See there for further documentation.
+func UninstrumentedHandler() http.Handler {
+	return http.HandlerFunc(func(rsp http.ResponseWriter, req *http.Request) {
+		mfs, err := DefaultGatherer.Gather()
+		if err != nil {
+			httpError(rsp, err)
+			return
+		}
+
+		contentType := expfmt.Negotiate(req.Header)
+		header := rsp.Header()
+		header.Set(contentTypeHeader, string(contentType))
+
+		w := io.Writer(rsp)
+		if gzipAccepted(req.Header) {
+			header.Set(contentEncodingHeader, "gzip")
+			gz := gzipPool.Get().(*gzip.Writer)
+			defer gzipPool.Put(gz)
+
+			gz.Reset(w)
+			defer gz.Close()
+
+			w = gz
+		}
+
+		enc := expfmt.NewEncoder(w, contentType)
+
+		for _, mf := range mfs {
+			if err := enc.Encode(mf); err != nil {
+				httpError(rsp, err)
+				return
+			}
+		}
+	})
+}
+
+var instLabels = []string{"method", "code"}
+
+type nower interface {
+	Now() time.Time
+}
+
+type nowFunc func() time.Time
+
+func (n nowFunc) Now() time.Time {
+	return n()
+}
+
+var now nower = nowFunc(func() time.Time {
+	return time.Now()
+})
+
+// InstrumentHandler wraps the given HTTP handler for instrumentation. It
+// registers four metric collectors (if not already done) and reports HTTP
+// metrics to the (newly or already) registered collectors: http_requests_total
+// (CounterVec), http_request_duration_microseconds (Summary),
+// http_request_size_bytes (Summary), http_response_size_bytes (Summary). Each
+// has a constant label named "handler" with the provided handlerName as
+// value. http_requests_total is a metric vector partitioned by HTTP method
+// (label name "method") and HTTP status code (label name "code").
+//
+// Deprecated: InstrumentHandler has several issues. Use the tooling provided in
+// package promhttp instead. The issues are the following: (1) It uses Summaries
+// rather than Histograms. Summaries are not useful if aggregation across
+// multiple instances is required. (2) It uses microseconds as unit, which is
+// deprecated and should be replaced by seconds. (3) The size of the request is
+// calculated in a separate goroutine. Since this calculator requires access to
+// the request header, it creates a race with any writes to the header performed
+// during request handling.  httputil.ReverseProxy is a prominent example for a
+// handler performing such writes. (4) It has additional issues with HTTP/2, cf.
+// https://github.com/prometheus/client_golang/issues/272.
+func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFunc wraps the given function for instrumentation. It
+// otherwise works in the same way as InstrumentHandler (and shares the same
+// issues).
+//
+// Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
+// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(
+		SummaryOpts{
+			Subsystem:   "http",
+			ConstLabels: Labels{"handler": handlerName},
+			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
+		},
+		handlerFunc,
+	)
+}
+
+// InstrumentHandlerWithOpts works like InstrumentHandler (and shares the same
+// issues) but provides more flexibility (at the cost of a more complex call
+// syntax). As InstrumentHandler, this function registers four metric
+// collectors, but it uses the provided SummaryOpts to create them. However, the
+// fields "Name" and "Help" in the SummaryOpts are ignored. "Name" is replaced
+// by "requests_total", "request_duration_microseconds", "request_size_bytes",
+// and "response_size_bytes", respectively. "Help" is replaced by an appropriate
+// help string. The names of the variable labels of the http_requests_total
+// CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
+//
+// If InstrumentHandlerWithOpts is called as follows, it mimics exactly the
+// behavior of InstrumentHandler:
+//
+//     prometheus.InstrumentHandlerWithOpts(
+//         prometheus.SummaryOpts{
+//              Subsystem:   "http",
+//              ConstLabels: prometheus.Labels{"handler": handlerName},
+//         },
+//         handler,
+//     )
+//
+// Technical detail: "requests_total" is a CounterVec, not a SummaryVec, so it
+// cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
+// and all its fields are set to the equally named fields in the provided
+// SummaryOpts.
+//
+// Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
+// InstrumentHandler is. Use the tooling provided in package promhttp instead.
+func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc (and shares
+// the same issues) but provides more flexibility (at the cost of a more complex
+// call syntax). See InstrumentHandlerWithOpts for details how the provided
+// SummaryOpts are used.
+//
+// Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
+// as InstrumentHandler is. Use the tooling provided in package promhttp instead.
+func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	reqCnt := NewCounterVec(
+		CounterOpts{
+			Namespace:   opts.Namespace,
+			Subsystem:   opts.Subsystem,
+			Name:        "requests_total",
+			Help:        "Total number of HTTP requests made.",
+			ConstLabels: opts.ConstLabels,
+		},
+		instLabels,
+	)
+	if err := Register(reqCnt); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			reqCnt = are.ExistingCollector.(*CounterVec)
+		} else {
+			panic(err)
+		}
+	}
+
+	opts.Name = "request_duration_microseconds"
+	opts.Help = "The HTTP request latencies in microseconds."
+	reqDur := NewSummary(opts)
+	if err := Register(reqDur); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			reqDur = are.ExistingCollector.(Summary)
+		} else {
+			panic(err)
+		}
+	}
+
+	opts.Name = "request_size_bytes"
+	opts.Help = "The HTTP request sizes in bytes."
+	reqSz := NewSummary(opts)
+	if err := Register(reqSz); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			reqSz = are.ExistingCollector.(Summary)
+		} else {
+			panic(err)
+		}
+	}
+
+	opts.Name = "response_size_bytes"
+	opts.Help = "The HTTP response sizes in bytes."
+	resSz := NewSummary(opts)
+	if err := Register(resSz); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			resSz = are.ExistingCollector.(Summary)
+		} else {
+			panic(err)
+		}
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		now := time.Now()
+
+		delegate := &responseWriterDelegator{ResponseWriter: w}
+		out := computeApproximateRequestSize(r)
+
+		_, cn := w.(http.CloseNotifier)
+		_, fl := w.(http.Flusher)
+		_, hj := w.(http.Hijacker)
+		_, rf := w.(io.ReaderFrom)
+		var rw http.ResponseWriter
+		if cn && fl && hj && rf {
+			rw = &fancyResponseWriterDelegator{delegate}
+		} else {
+			rw = delegate
+		}
+		handlerFunc(rw, r)
+
+		elapsed := float64(time.Since(now)) / float64(time.Microsecond)
+
+		method := sanitizeMethod(r.Method)
+		code := sanitizeCode(delegate.status)
+		reqCnt.WithLabelValues(method, code).Inc()
+		reqDur.Observe(elapsed)
+		resSz.Observe(float64(delegate.written))
+		reqSz.Observe(float64(<-out))
+	})
+}
+
+func computeApproximateRequestSize(r *http.Request) <-chan int {
+	// Get URL length in current goroutine for avoiding a race condition.
+	// HandlerFunc that runs in parallel may modify the URL.
+	s := 0
+	if r.URL != nil {
+		s += len(r.URL.String())
+	}
+
+	out := make(chan int, 1)
+
+	go func() {
+		s += len(r.Method)
+		s += len(r.Proto)
+		for name, values := range r.Header {
+			s += len(name)
+			for _, value := range values {
+				s += len(value)
+			}
+		}
+		s += len(r.Host)
+
+		// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
+
+		if r.ContentLength != -1 {
+			s += int(r.ContentLength)
+		}
+		out <- s
+		close(out)
+	}()
+
+	return out
+}
+
+type responseWriterDelegator struct {
+	http.ResponseWriter
+
+	status      int
+	written     int64
+	wroteHeader bool
+}
+
+func (r *responseWriterDelegator) WriteHeader(code int) {
+	r.status = code
+	r.wroteHeader = true
+	r.ResponseWriter.WriteHeader(code)
+}
+
+func (r *responseWriterDelegator) Write(b []byte) (int, error) {
+	if !r.wroteHeader {
+		r.WriteHeader(http.StatusOK)
+	}
+	n, err := r.ResponseWriter.Write(b)
+	r.written += int64(n)
+	return n, err
+}
+
+type fancyResponseWriterDelegator struct {
+	*responseWriterDelegator
+}
+
+func (f *fancyResponseWriterDelegator) CloseNotify() <-chan bool {
+	return f.ResponseWriter.(http.CloseNotifier).CloseNotify()
+}
+
+func (f *fancyResponseWriterDelegator) Flush() {
+	f.ResponseWriter.(http.Flusher).Flush()
+}
+
+func (f *fancyResponseWriterDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return f.ResponseWriter.(http.Hijacker).Hijack()
+}
+
+func (f *fancyResponseWriterDelegator) ReadFrom(r io.Reader) (int64, error) {
+	if !f.wroteHeader {
+		f.WriteHeader(http.StatusOK)
+	}
+	n, err := f.ResponseWriter.(io.ReaderFrom).ReadFrom(r)
+	f.written += n
+	return n, err
+}
+
+func sanitizeMethod(m string) string {
+	switch m {
+	case "GET", "get":
+		return "get"
+	case "PUT", "put":
+		return "put"
+	case "HEAD", "head":
+		return "head"
+	case "POST", "post":
+		return "post"
+	case "DELETE", "delete":
+		return "delete"
+	case "CONNECT", "connect":
+		return "connect"
+	case "OPTIONS", "options":
+		return "options"
+	case "NOTIFY", "notify":
+		return "notify"
+	default:
+		return strings.ToLower(m)
+	}
+}
+
+func sanitizeCode(s int) string {
+	switch s {
+	case 100:
+		return "100"
+	case 101:
+		return "101"
+
+	case 200:
+		return "200"
+	case 201:
+		return "201"
+	case 202:
+		return "202"
+	case 203:
+		return "203"
+	case 204:
+		return "204"
+	case 205:
+		return "205"
+	case 206:
+		return "206"
+
+	case 300:
+		return "300"
+	case 301:
+		return "301"
+	case 302:
+		return "302"
+	case 304:
+		return "304"
+	case 305:
+		return "305"
+	case 307:
+		return "307"
+
+	case 400:
+		return "400"
+	case 401:
+		return "401"
+	case 402:
+		return "402"
+	case 403:
+		return "403"
+	case 404:
+		return "404"
+	case 405:
+		return "405"
+	case 406:
+		return "406"
+	case 407:
+		return "407"
+	case 408:
+		return "408"
+	case 409:
+		return "409"
+	case 410:
+		return "410"
+	case 411:
+		return "411"
+	case 412:
+		return "412"
+	case 413:
+		return "413"
+	case 414:
+		return "414"
+	case 415:
+		return "415"
+	case 416:
+		return "416"
+	case 417:
+		return "417"
+	case 418:
+		return "418"
+
+	case 500:
+		return "500"
+	case 501:
+		return "501"
+	case 502:
+		return "502"
+	case 503:
+		return "503"
+	case 504:
+		return "504"
+	case 505:
+		return "505"
+
+	case 428:
+		return "428"
+	case 429:
+		return "429"
+	case 431:
+		return "431"
+	case 511:
+		return "511"
+
+	default:
+		return strconv.Itoa(s)
+	}
+}
+
+// gzipAccepted returns whether the client will accept gzip-encoded content.
+func gzipAccepted(header http.Header) bool {
+	a := header.Get(acceptEncodingHeader)
+	parts := strings.Split(a, ",")
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
+			return true
+		}
+	}
+	return false
+}
+
+// httpError removes any content-encoding header and then calls http.Error with
+// the provided error and http.StatusInternalServerErrer. Error contents is
+// supposed to be uncompressed plain text. However, same as with a plain
+// http.Error, any header settings will be void if the header has already been
+// sent. The error message will still be written to the writer, but it will
+// probably be of limited use.
+func httpError(rsp http.ResponseWriter, err error) {
+	rsp.Header().Del(contentEncodingHeader)
+	http.Error(
+		rsp,
+		"An error has occurred while serving metrics:\n\n"+err.Error(),
+		http.StatusInternalServerError,
+	)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go
new file mode 100644
index 0000000000..351c26e1ae
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/internal/metric.go
@@ -0,0 +1,85 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal
+
+import (
+	"sort"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// metricSorter is a sortable slice of *dto.Metric.
+type metricSorter []*dto.Metric
+
+func (s metricSorter) Len() int {
+	return len(s)
+}
+
+func (s metricSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s metricSorter) Less(i, j int) bool {
+	if len(s[i].Label) != len(s[j].Label) {
+		// This should not happen. The metrics are
+		// inconsistent. However, we have to deal with the fact, as
+		// people might use custom collectors or metric family injection
+		// to create inconsistent metrics. So let's simply compare the
+		// number of labels in this case. That will still yield
+		// reproducible sorting.
+		return len(s[i].Label) < len(s[j].Label)
+	}
+	for n, lp := range s[i].Label {
+		vi := lp.GetValue()
+		vj := s[j].Label[n].GetValue()
+		if vi != vj {
+			return vi < vj
+		}
+	}
+
+	// We should never arrive here. Multiple metrics with the same
+	// label set in the same scrape will lead to undefined ingestion
+	// behavior. However, as above, we have to provide stable sorting
+	// here, even for inconsistent metrics. So sort equal metrics
+	// by their timestamp, with missing timestamps (implying "now")
+	// coming last.
+	if s[i].TimestampMs == nil {
+		return false
+	}
+	if s[j].TimestampMs == nil {
+		return true
+	}
+	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
+}
+
+// NormalizeMetricFamilies returns a MetricFamily slice with empty
+// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
+// the slice, with the contained Metrics sorted within each MetricFamily.
+func NormalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
+	for _, mf := range metricFamiliesByName {
+		sort.Sort(metricSorter(mf.Metric))
+	}
+	names := make([]string, 0, len(metricFamiliesByName))
+	for name, mf := range metricFamiliesByName {
+		if len(mf.Metric) > 0 {
+			names = append(names, name)
+		}
+	}
+	sort.Strings(names)
+	result := make([]*dto.MetricFamily, 0, len(names))
+	for _, name := range names {
+		result = append(result, metricFamiliesByName[name])
+	}
+	return result
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/labels.go b/vendor/github.com/prometheus/client_golang/prometheus/labels.go
new file mode 100644
index 0000000000..2744443ac2
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/labels.go
@@ -0,0 +1,87 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+
+	"github.com/prometheus/common/model"
+)
+
+// Labels represents a collection of label name -> value mappings. This type is
+// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
+// metric vector Collectors, e.g.:
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//
+// The other use-case is the specification of constant label pairs in Opts or to
+// create a Desc.
+type Labels map[string]string
+
+// reservedLabelPrefix is a prefix which is not legal in user-supplied
+// label names.
+const reservedLabelPrefix = "__"
+
+var errInconsistentCardinality = errors.New("inconsistent label cardinality")
+
+func makeInconsistentCardinalityError(fqName string, labels, labelValues []string) error {
+	return fmt.Errorf(
+		"%s: %q has %d variable labels named %q but %d values %q were provided",
+		errInconsistentCardinality, fqName,
+		len(labels), labels,
+		len(labelValues), labelValues,
+	)
+}
+
+func validateValuesInLabels(labels Labels, expectedNumberOfValues int) error {
+	if len(labels) != expectedNumberOfValues {
+		return fmt.Errorf(
+			"%s: expected %d label values but got %d in %#v",
+			errInconsistentCardinality, expectedNumberOfValues,
+			len(labels), labels,
+		)
+	}
+
+	for name, val := range labels {
+		if !utf8.ValidString(val) {
+			return fmt.Errorf("label %s: value %q is not valid UTF-8", name, val)
+		}
+	}
+
+	return nil
+}
+
+func validateLabelValues(vals []string, expectedNumberOfValues int) error {
+	if len(vals) != expectedNumberOfValues {
+		return fmt.Errorf(
+			"%s: expected %d label values but got %d in %#v",
+			errInconsistentCardinality, expectedNumberOfValues,
+			len(vals), vals,
+		)
+	}
+
+	for _, val := range vals {
+		if !utf8.ValidString(val) {
+			return fmt.Errorf("label value %q is not valid UTF-8", val)
+		}
+	}
+
+	return nil
+}
+
+func checkLabelName(l string) bool {
+	return model.LabelName(l).IsValid() && !strings.HasPrefix(l, reservedLabelPrefix)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/metric.go
new file mode 100644
index 0000000000..55e6d86d59
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/metric.go
@@ -0,0 +1,174 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"strings"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+const separatorByte byte = 255
+
+// A Metric models a single sample value with its meta data being exported to
+// Prometheus. Implementations of Metric in this package are Gauge, Counter,
+// Histogram, Summary, and Untyped.
+type Metric interface {
+	// Desc returns the descriptor for the Metric. This method idempotently
+	// returns the same descriptor throughout the lifetime of the
+	// Metric. The returned descriptor is immutable by contract. A Metric
+	// unable to describe itself must return an invalid descriptor (created
+	// with NewInvalidDesc).
+	Desc() *Desc
+	// Write encodes the Metric into a "Metric" Protocol Buffer data
+	// transmission object.
+	//
+	// Metric implementations must observe concurrency safety as reads of
+	// this metric may occur at any time, and any blocking occurs at the
+	// expense of total performance of rendering all registered
+	// metrics. Ideally, Metric implementations should support concurrent
+	// readers.
+	//
+	// While populating dto.Metric, it is the responsibility of the
+	// implementation to ensure validity of the Metric protobuf (like valid
+	// UTF-8 strings or syntactically valid metric and label names). It is
+	// recommended to sort labels lexicographically. Callers of Write should
+	// still make sure of sorting if they depend on it.
+	Write(*dto.Metric) error
+	// TODO(beorn7): The original rationale of passing in a pre-allocated
+	// dto.Metric protobuf to save allocations has disappeared. The
+	// signature of this method should be changed to "Write() (*dto.Metric,
+	// error)".
+}
+
+// Opts bundles the options for creating most Metric types. Each metric
+// implementation XXX has its own XXXOpts type, but in most cases, it is just be
+// an alias of this type (which might change when the requirement arises.)
+//
+// It is mandatory to set Name to a non-empty string. All other fields are
+// optional and can safely be left at their zero value, although it is strongly
+// encouraged to set a Help string.
+type Opts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Metric (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the metric must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this metric.
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
+	// with the same fully-qualified name must have the same label names in
+	// their ConstLabels.
+	//
+	// ConstLabels are only used rarely. In particular, do not use them to
+	// attach the same labels to all your metrics. Those use cases are
+	// better covered by target labels set by the scraping Prometheus
+	// server, or by one specific metric (e.g. a build_info or a
+	// machine_role metric). See also
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
+	ConstLabels Labels
+}
+
+// BuildFQName joins the given three name components by "_". Empty name
+// components are ignored. If the name parameter itself is empty, an empty
+// string is returned, no matter what. Metric implementations included in this
+// library use this function internally to generate the fully-qualified metric
+// name from the name component in their Opts. Users of the library will only
+// need this function if they implement their own Metric or instantiate a Desc
+// (with NewDesc) directly.
+func BuildFQName(namespace, subsystem, name string) string {
+	if name == "" {
+		return ""
+	}
+	switch {
+	case namespace != "" && subsystem != "":
+		return strings.Join([]string{namespace, subsystem, name}, "_")
+	case namespace != "":
+		return strings.Join([]string{namespace, name}, "_")
+	case subsystem != "":
+		return strings.Join([]string{subsystem, name}, "_")
+	}
+	return name
+}
+
+// labelPairSorter implements sort.Interface. It is used to sort a slice of
+// dto.LabelPair pointers.
+type labelPairSorter []*dto.LabelPair
+
+func (s labelPairSorter) Len() int {
+	return len(s)
+}
+
+func (s labelPairSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s labelPairSorter) Less(i, j int) bool {
+	return s[i].GetName() < s[j].GetName()
+}
+
+type invalidMetric struct {
+	desc *Desc
+	err  error
+}
+
+// NewInvalidMetric returns a metric whose Write method always returns the
+// provided error. It is useful if a Collector finds itself unable to collect
+// a metric and wishes to report an error to the registry.
+func NewInvalidMetric(desc *Desc, err error) Metric {
+	return &invalidMetric{desc, err}
+}
+
+func (m *invalidMetric) Desc() *Desc { return m.desc }
+
+func (m *invalidMetric) Write(*dto.Metric) error { return m.err }
+
+type timestampedMetric struct {
+	Metric
+	t time.Time
+}
+
+func (m timestampedMetric) Write(pb *dto.Metric) error {
+	e := m.Metric.Write(pb)
+	pb.TimestampMs = proto.Int64(m.t.Unix()*1000 + int64(m.t.Nanosecond()/1000000))
+	return e
+}
+
+// NewMetricWithTimestamp returns a new Metric wrapping the provided Metric in a
+// way that it has an explicit timestamp set to the provided Time. This is only
+// useful in rare cases as the timestamp of a Prometheus metric should usually
+// be set by the Prometheus server during scraping. Exceptions include mirroring
+// metrics with given timestamps from other metric
+// sources.
+//
+// NewMetricWithTimestamp works best with MustNewConstMetric,
+// MustNewConstHistogram, and MustNewConstSummary, see example.
+//
+// Currently, the exposition formats used by Prometheus are limited to
+// millisecond resolution. Thus, the provided time will be rounded down to the
+// next full millisecond value.
+func NewMetricWithTimestamp(t time.Time, m Metric) Metric {
+	return timestampedMetric{Metric: m, t: t}
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/observer.go b/vendor/github.com/prometheus/client_golang/prometheus/observer.go
new file mode 100644
index 0000000000..5806cd09e3
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/observer.go
@@ -0,0 +1,52 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Observer is the interface that wraps the Observe method, which is used by
+// Histogram and Summary to add observations.
+type Observer interface {
+	Observe(float64)
+}
+
+// The ObserverFunc type is an adapter to allow the use of ordinary
+// functions as Observers. If f is a function with the appropriate
+// signature, ObserverFunc(f) is an Observer that calls f.
+//
+// This adapter is usually used in connection with the Timer type, and there are
+// two general use cases:
+//
+// The most common one is to use a Gauge as the Observer for a Timer.
+// See the "Gauge" Timer example.
+//
+// The more advanced use case is to create a function that dynamically decides
+// which Observer to use for observing the duration. See the "Complex" Timer
+// example.
+type ObserverFunc func(float64)
+
+// Observe calls f(value). It implements Observer.
+func (f ObserverFunc) Observe(value float64) {
+	f(value)
+}
+
+// ObserverVec is an interface implemented by `HistogramVec` and `SummaryVec`.
+type ObserverVec interface {
+	GetMetricWith(Labels) (Observer, error)
+	GetMetricWithLabelValues(lvs ...string) (Observer, error)
+	With(Labels) Observer
+	WithLabelValues(...string) Observer
+	CurryWith(Labels) (ObserverVec, error)
+	MustCurryWith(Labels) ObserverVec
+
+	Collector
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go
new file mode 100644
index 0000000000..55176d58ce
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go
@@ -0,0 +1,204 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"os"
+
+	"github.com/prometheus/procfs"
+)
+
+type processCollector struct {
+	collectFn       func(chan<- Metric)
+	pidFn           func() (int, error)
+	reportErrors    bool
+	cpuTotal        *Desc
+	openFDs, maxFDs *Desc
+	vsize, maxVsize *Desc
+	rss             *Desc
+	startTime       *Desc
+}
+
+// ProcessCollectorOpts defines the behavior of a process metrics collector
+// created with NewProcessCollector.
+type ProcessCollectorOpts struct {
+	// PidFn returns the PID of the process the collector collects metrics
+	// for. It is called upon each collection. By default, the PID of the
+	// current process is used, as determined on construction time by
+	// calling os.Getpid().
+	PidFn func() (int, error)
+	// If non-empty, each of the collected metrics is prefixed by the
+	// provided string and an underscore ("_").
+	Namespace string
+	// If true, any error encountered during collection is reported as an
+	// invalid metric (see NewInvalidMetric). Otherwise, errors are ignored
+	// and the collected metrics will be incomplete. (Possibly, no metrics
+	// will be collected at all.) While that's usually not desired, it is
+	// appropriate for the common "mix-in" of process metrics, where process
+	// metrics are nice to have, but failing to collect them should not
+	// disrupt the collection of the remaining metrics.
+	ReportErrors bool
+}
+
+// NewProcessCollector returns a collector which exports the current state of
+// process metrics including CPU, memory and file descriptor usage as well as
+// the process start time. The detailed behavior is defined by the provided
+// ProcessCollectorOpts. The zero value of ProcessCollectorOpts creates a
+// collector for the current process with an empty namespace string and no error
+// reporting.
+//
+// Currently, the collector depends on a Linux-style proc filesystem and
+// therefore only exports metrics for Linux.
+//
+// Note: An older version of this function had the following signature:
+//
+//     NewProcessCollector(pid int, namespace string) Collector
+//
+// Most commonly, it was called as
+//
+//     NewProcessCollector(os.Getpid(), "")
+//
+// The following call of the current version is equivalent to the above:
+//
+//     NewProcessCollector(ProcessCollectorOpts{})
+func NewProcessCollector(opts ProcessCollectorOpts) Collector {
+	ns := ""
+	if len(opts.Namespace) > 0 {
+		ns = opts.Namespace + "_"
+	}
+
+	c := &processCollector{
+		reportErrors: opts.ReportErrors,
+		cpuTotal: NewDesc(
+			ns+"process_cpu_seconds_total",
+			"Total user and system CPU time spent in seconds.",
+			nil, nil,
+		),
+		openFDs: NewDesc(
+			ns+"process_open_fds",
+			"Number of open file descriptors.",
+			nil, nil,
+		),
+		maxFDs: NewDesc(
+			ns+"process_max_fds",
+			"Maximum number of open file descriptors.",
+			nil, nil,
+		),
+		vsize: NewDesc(
+			ns+"process_virtual_memory_bytes",
+			"Virtual memory size in bytes.",
+			nil, nil,
+		),
+		maxVsize: NewDesc(
+			ns+"process_virtual_memory_max_bytes",
+			"Maximum amount of virtual memory available in bytes.",
+			nil, nil,
+		),
+		rss: NewDesc(
+			ns+"process_resident_memory_bytes",
+			"Resident memory size in bytes.",
+			nil, nil,
+		),
+		startTime: NewDesc(
+			ns+"process_start_time_seconds",
+			"Start time of the process since unix epoch in seconds.",
+			nil, nil,
+		),
+	}
+
+	if opts.PidFn == nil {
+		pid := os.Getpid()
+		c.pidFn = func() (int, error) { return pid, nil }
+	} else {
+		c.pidFn = opts.PidFn
+	}
+
+	// Set up process metric collection if supported by the runtime.
+	if _, err := procfs.NewStat(); err == nil {
+		c.collectFn = c.processCollect
+	} else {
+		c.collectFn = func(ch chan<- Metric) {
+			c.reportError(ch, nil, errors.New("process metrics not supported on this platform"))
+		}
+	}
+
+	return c
+}
+
+// Describe returns all descriptions of the collector.
+func (c *processCollector) Describe(ch chan<- *Desc) {
+	ch <- c.cpuTotal
+	ch <- c.openFDs
+	ch <- c.maxFDs
+	ch <- c.vsize
+	ch <- c.maxVsize
+	ch <- c.rss
+	ch <- c.startTime
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *processCollector) Collect(ch chan<- Metric) {
+	c.collectFn(ch)
+}
+
+func (c *processCollector) processCollect(ch chan<- Metric) {
+	pid, err := c.pidFn()
+	if err != nil {
+		c.reportError(ch, nil, err)
+		return
+	}
+
+	p, err := procfs.NewProc(pid)
+	if err != nil {
+		c.reportError(ch, nil, err)
+		return
+	}
+
+	if stat, err := p.NewStat(); err == nil {
+		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
+		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
+		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
+		if startTime, err := stat.StartTime(); err == nil {
+			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
+		} else {
+			c.reportError(ch, c.startTime, err)
+		}
+	} else {
+		c.reportError(ch, nil, err)
+	}
+
+	if fds, err := p.FileDescriptorsLen(); err == nil {
+		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
+	} else {
+		c.reportError(ch, c.openFDs, err)
+	}
+
+	if limits, err := p.NewLimits(); err == nil {
+		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
+		ch <- MustNewConstMetric(c.maxVsize, GaugeValue, float64(limits.AddressSpace))
+	} else {
+		c.reportError(ch, nil, err)
+	}
+}
+
+func (c *processCollector) reportError(ch chan<- Metric, desc *Desc, err error) {
+	if !c.reportErrors {
+		return
+	}
+	if desc == nil {
+		desc = NewInvalidDesc(err)
+	}
+	ch <- NewInvalidMetric(desc, err)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go
new file mode 100644
index 0000000000..67b56d37cf
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go
@@ -0,0 +1,199 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package promhttp
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+const (
+	closeNotifier = 1 << iota
+	flusher
+	hijacker
+	readerFrom
+	pusher
+)
+
+type delegator interface {
+	http.ResponseWriter
+
+	Status() int
+	Written() int64
+}
+
+type responseWriterDelegator struct {
+	http.ResponseWriter
+
+	handler, method    string
+	status             int
+	written            int64
+	wroteHeader        bool
+	observeWriteHeader func(int)
+}
+
+func (r *responseWriterDelegator) Status() int {
+	return r.status
+}
+
+func (r *responseWriterDelegator) Written() int64 {
+	return r.written
+}
+
+func (r *responseWriterDelegator) WriteHeader(code int) {
+	r.status = code
+	r.wroteHeader = true
+	r.ResponseWriter.WriteHeader(code)
+	if r.observeWriteHeader != nil {
+		r.observeWriteHeader(code)
+	}
+}
+
+func (r *responseWriterDelegator) Write(b []byte) (int, error) {
+	if !r.wroteHeader {
+		r.WriteHeader(http.StatusOK)
+	}
+	n, err := r.ResponseWriter.Write(b)
+	r.written += int64(n)
+	return n, err
+}
+
+type closeNotifierDelegator struct{ *responseWriterDelegator }
+type flusherDelegator struct{ *responseWriterDelegator }
+type hijackerDelegator struct{ *responseWriterDelegator }
+type readerFromDelegator struct{ *responseWriterDelegator }
+
+func (d closeNotifierDelegator) CloseNotify() <-chan bool {
+	return d.ResponseWriter.(http.CloseNotifier).CloseNotify()
+}
+func (d flusherDelegator) Flush() {
+	d.ResponseWriter.(http.Flusher).Flush()
+}
+func (d hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return d.ResponseWriter.(http.Hijacker).Hijack()
+}
+func (d readerFromDelegator) ReadFrom(re io.Reader) (int64, error) {
+	if !d.wroteHeader {
+		d.WriteHeader(http.StatusOK)
+	}
+	n, err := d.ResponseWriter.(io.ReaderFrom).ReadFrom(re)
+	d.written += n
+	return n, err
+}
+
+var pickDelegator = make([]func(*responseWriterDelegator) delegator, 32)
+
+func init() {
+	// TODO(beorn7): Code generation would help here.
+	pickDelegator[0] = func(d *responseWriterDelegator) delegator { // 0
+		return d
+	}
+	pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1
+		return closeNotifierDelegator{d}
+	}
+	pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2
+		return flusherDelegator{d}
+	}
+	pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3
+		return struct {
+			*responseWriterDelegator
+			http.Flusher
+			http.CloseNotifier
+		}{d, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4
+		return hijackerDelegator{d}
+	}
+	pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5
+		return struct {
+			*responseWriterDelegator
+			http.Hijacker
+			http.CloseNotifier
+		}{d, hijackerDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 6
+		return struct {
+			*responseWriterDelegator
+			http.Hijacker
+			http.Flusher
+		}{d, hijackerDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 7
+		return struct {
+			*responseWriterDelegator
+			http.Hijacker
+			http.Flusher
+			http.CloseNotifier
+		}{d, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[readerFrom] = func(d *responseWriterDelegator) delegator { // 8
+		return readerFromDelegator{d}
+	}
+	pickDelegator[readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 9
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.CloseNotifier
+		}{d, readerFromDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 10
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Flusher
+		}{d, readerFromDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 11
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Flusher
+			http.CloseNotifier
+		}{d, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 12
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Hijacker
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}}
+	}
+	pickDelegator[readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 13
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Hijacker
+			http.CloseNotifier
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 14
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Hijacker
+			http.Flusher
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 15
+		return struct {
+			*responseWriterDelegator
+			io.ReaderFrom
+			http.Hijacker
+			http.Flusher
+			http.CloseNotifier
+		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go
new file mode 100644
index 0000000000..31a7069569
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go
@@ -0,0 +1,181 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.8
+
+package promhttp
+
+import (
+	"io"
+	"net/http"
+)
+
+type pusherDelegator struct{ *responseWriterDelegator }
+
+func (d pusherDelegator) Push(target string, opts *http.PushOptions) error {
+	return d.ResponseWriter.(http.Pusher).Push(target, opts)
+}
+
+func init() {
+	pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16
+		return pusherDelegator{d}
+	}
+	pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+flusher] = func(d *responseWriterDelegator) delegator { // 18
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Flusher
+		}{d, pusherDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[pusher+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 19
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Flusher
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+hijacker] = func(d *responseWriterDelegator) delegator { // 20
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Hijacker
+		}{d, pusherDelegator{d}, hijackerDelegator{d}}
+	}
+	pickDelegator[pusher+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 21
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Hijacker
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 22
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Hijacker
+			http.Flusher
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[pusher+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { //23
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			http.Hijacker
+			http.Flusher
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom] = func(d *responseWriterDelegator) delegator { // 24
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+		}{d, pusherDelegator{d}, readerFromDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 25
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 26
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Flusher
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 27
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Flusher
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 28
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Hijacker
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 29
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Hijacker
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 30
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Hijacker
+			http.Flusher
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
+	}
+	pickDelegator[pusher+readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 31
+		return struct {
+			*responseWriterDelegator
+			http.Pusher
+			io.ReaderFrom
+			http.Hijacker
+			http.Flusher
+			http.CloseNotifier
+		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
+	}
+}
+
+func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
+	d := &responseWriterDelegator{
+		ResponseWriter:     w,
+		observeWriteHeader: observeWriteHeaderFunc,
+	}
+
+	id := 0
+	if _, ok := w.(http.CloseNotifier); ok {
+		id += closeNotifier
+	}
+	if _, ok := w.(http.Flusher); ok {
+		id += flusher
+	}
+	if _, ok := w.(http.Hijacker); ok {
+		id += hijacker
+	}
+	if _, ok := w.(io.ReaderFrom); ok {
+		id += readerFrom
+	}
+	if _, ok := w.(http.Pusher); ok {
+		id += pusher
+	}
+
+	return pickDelegator[id](d)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go
new file mode 100644
index 0000000000..8bb9b8b68f
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go
@@ -0,0 +1,44 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !go1.8
+
+package promhttp
+
+import (
+	"io"
+	"net/http"
+)
+
+func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
+	d := &responseWriterDelegator{
+		ResponseWriter:     w,
+		observeWriteHeader: observeWriteHeaderFunc,
+	}
+
+	id := 0
+	if _, ok := w.(http.CloseNotifier); ok {
+		id += closeNotifier
+	}
+	if _, ok := w.(http.Flusher); ok {
+		id += flusher
+	}
+	if _, ok := w.(http.Hijacker); ok {
+		id += hijacker
+	}
+	if _, ok := w.(io.ReaderFrom); ok {
+		id += readerFrom
+	}
+
+	return pickDelegator[id](d)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go
new file mode 100644
index 0000000000..668eb6b3c9
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go
@@ -0,0 +1,311 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package promhttp provides tooling around HTTP servers and clients.
+//
+// First, the package allows the creation of http.Handler instances to expose
+// Prometheus metrics via HTTP. promhttp.Handler acts on the
+// prometheus.DefaultGatherer. With HandlerFor, you can create a handler for a
+// custom registry or anything that implements the Gatherer interface. It also
+// allows the creation of handlers that act differently on errors or allow to
+// log errors.
+//
+// Second, the package provides tooling to instrument instances of http.Handler
+// via middleware. Middleware wrappers follow the naming scheme
+// InstrumentHandlerX, where X describes the intended use of the middleware.
+// See each function's doc comment for specific details.
+//
+// Finally, the package allows for an http.RoundTripper to be instrumented via
+// middleware. Middleware wrappers follow the naming scheme
+// InstrumentRoundTripperX, where X describes the intended use of the
+// middleware. See each function's doc comment for specific details.
+package promhttp
+
+import (
+	"compress/gzip"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/prometheus/common/expfmt"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	contentTypeHeader     = "Content-Type"
+	contentLengthHeader   = "Content-Length"
+	contentEncodingHeader = "Content-Encoding"
+	acceptEncodingHeader  = "Accept-Encoding"
+)
+
+var gzipPool = sync.Pool{
+	New: func() interface{} {
+		return gzip.NewWriter(nil)
+	},
+}
+
+// Handler returns an http.Handler for the prometheus.DefaultGatherer, using
+// default HandlerOpts, i.e. it reports the first error as an HTTP error, it has
+// no error logging, and it applies compression if requested by the client.
+//
+// The returned http.Handler is already instrumented using the
+// InstrumentMetricHandler function and the prometheus.DefaultRegisterer. If you
+// create multiple http.Handlers by separate calls of the Handler function, the
+// metrics used for instrumentation will be shared between them, providing
+// global scrape counts.
+//
+// This function is meant to cover the bulk of basic use cases. If you are doing
+// anything that requires more customization (including using a non-default
+// Gatherer, different instrumentation, and non-default HandlerOpts), use the
+// HandlerFor function. See there for details.
+func Handler() http.Handler {
+	return InstrumentMetricHandler(
+		prometheus.DefaultRegisterer, HandlerFor(prometheus.DefaultGatherer, HandlerOpts{}),
+	)
+}
+
+// HandlerFor returns an uninstrumented http.Handler for the provided
+// Gatherer. The behavior of the Handler is defined by the provided
+// HandlerOpts. Thus, HandlerFor is useful to create http.Handlers for custom
+// Gatherers, with non-default HandlerOpts, and/or with custom (or no)
+// instrumentation. Use the InstrumentMetricHandler function to apply the same
+// kind of instrumentation as it is used by the Handler function.
+func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler {
+	var inFlightSem chan struct{}
+	if opts.MaxRequestsInFlight > 0 {
+		inFlightSem = make(chan struct{}, opts.MaxRequestsInFlight)
+	}
+
+	h := http.HandlerFunc(func(rsp http.ResponseWriter, req *http.Request) {
+		if inFlightSem != nil {
+			select {
+			case inFlightSem <- struct{}{}: // All good, carry on.
+				defer func() { <-inFlightSem }()
+			default:
+				http.Error(rsp, fmt.Sprintf(
+					"Limit of concurrent requests reached (%d), try again later.", opts.MaxRequestsInFlight,
+				), http.StatusServiceUnavailable)
+				return
+			}
+		}
+		mfs, err := reg.Gather()
+		if err != nil {
+			if opts.ErrorLog != nil {
+				opts.ErrorLog.Println("error gathering metrics:", err)
+			}
+			switch opts.ErrorHandling {
+			case PanicOnError:
+				panic(err)
+			case ContinueOnError:
+				if len(mfs) == 0 {
+					// Still report the error if no metrics have been gathered.
+					httpError(rsp, err)
+					return
+				}
+			case HTTPErrorOnError:
+				httpError(rsp, err)
+				return
+			}
+		}
+
+		contentType := expfmt.Negotiate(req.Header)
+		header := rsp.Header()
+		header.Set(contentTypeHeader, string(contentType))
+
+		w := io.Writer(rsp)
+		if !opts.DisableCompression && gzipAccepted(req.Header) {
+			header.Set(contentEncodingHeader, "gzip")
+			gz := gzipPool.Get().(*gzip.Writer)
+			defer gzipPool.Put(gz)
+
+			gz.Reset(w)
+			defer gz.Close()
+
+			w = gz
+		}
+
+		enc := expfmt.NewEncoder(w, contentType)
+
+		var lastErr error
+		for _, mf := range mfs {
+			if err := enc.Encode(mf); err != nil {
+				lastErr = err
+				if opts.ErrorLog != nil {
+					opts.ErrorLog.Println("error encoding and sending metric family:", err)
+				}
+				switch opts.ErrorHandling {
+				case PanicOnError:
+					panic(err)
+				case ContinueOnError:
+					// Handled later.
+				case HTTPErrorOnError:
+					httpError(rsp, err)
+					return
+				}
+			}
+		}
+
+		if lastErr != nil {
+			httpError(rsp, lastErr)
+		}
+	})
+
+	if opts.Timeout <= 0 {
+		return h
+	}
+	return http.TimeoutHandler(h, opts.Timeout, fmt.Sprintf(
+		"Exceeded configured timeout of %v.\n",
+		opts.Timeout,
+	))
+}
+
+// InstrumentMetricHandler is usually used with an http.Handler returned by the
+// HandlerFor function. It instruments the provided http.Handler with two
+// metrics: A counter vector "promhttp_metric_handler_requests_total" to count
+// scrapes partitioned by HTTP status code, and a gauge
+// "promhttp_metric_handler_requests_in_flight" to track the number of
+// simultaneous scrapes. This function idempotently registers collectors for
+// both metrics with the provided Registerer. It panics if the registration
+// fails. The provided metrics are useful to see how many scrapes hit the
+// monitored target (which could be from different Prometheus servers or other
+// scrapers), and how often they overlap (which would result in more than one
+// scrape in flight at the same time). Note that the scrapes-in-flight gauge
+// will contain the scrape by which it is exposed, while the scrape counter will
+// only get incremented after the scrape is complete (as only then the status
+// code is known). For tracking scrape durations, use the
+// "scrape_duration_seconds" gauge created by the Prometheus server upon each
+// scrape.
+func InstrumentMetricHandler(reg prometheus.Registerer, handler http.Handler) http.Handler {
+	cnt := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "promhttp_metric_handler_requests_total",
+			Help: "Total number of scrapes by HTTP status code.",
+		},
+		[]string{"code"},
+	)
+	// Initialize the most likely HTTP status codes.
+	cnt.WithLabelValues("200")
+	cnt.WithLabelValues("500")
+	cnt.WithLabelValues("503")
+	if err := reg.Register(cnt); err != nil {
+		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
+			cnt = are.ExistingCollector.(*prometheus.CounterVec)
+		} else {
+			panic(err)
+		}
+	}
+
+	gge := prometheus.NewGauge(prometheus.GaugeOpts{
+		Name: "promhttp_metric_handler_requests_in_flight",
+		Help: "Current number of scrapes being served.",
+	})
+	if err := reg.Register(gge); err != nil {
+		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
+			gge = are.ExistingCollector.(prometheus.Gauge)
+		} else {
+			panic(err)
+		}
+	}
+
+	return InstrumentHandlerCounter(cnt, InstrumentHandlerInFlight(gge, handler))
+}
+
+// HandlerErrorHandling defines how a Handler serving metrics will handle
+// errors.
+type HandlerErrorHandling int
+
+// These constants cause handlers serving metrics to behave as described if
+// errors are encountered.
+const (
+	// Serve an HTTP status code 500 upon the first error
+	// encountered. Report the error message in the body.
+	HTTPErrorOnError HandlerErrorHandling = iota
+	// Ignore errors and try to serve as many metrics as possible.  However,
+	// if no metrics can be served, serve an HTTP status code 500 and the
+	// last error message in the body. Only use this in deliberate "best
+	// effort" metrics collection scenarios. It is recommended to at least
+	// log errors (by providing an ErrorLog in HandlerOpts) to not mask
+	// errors completely.
+	ContinueOnError
+	// Panic upon the first error encountered (useful for "crash only" apps).
+	PanicOnError
+)
+
+// Logger is the minimal interface HandlerOpts needs for logging. Note that
+// log.Logger from the standard library implements this interface, and it is
+// easy to implement by custom loggers, if they don't do so already anyway.
+type Logger interface {
+	Println(v ...interface{})
+}
+
+// HandlerOpts specifies options how to serve metrics via an http.Handler. The
+// zero value of HandlerOpts is a reasonable default.
+type HandlerOpts struct {
+	// ErrorLog specifies an optional logger for errors collecting and
+	// serving metrics. If nil, errors are not logged at all.
+	ErrorLog Logger
+	// ErrorHandling defines how errors are handled. Note that errors are
+	// logged regardless of the configured ErrorHandling provided ErrorLog
+	// is not nil.
+	ErrorHandling HandlerErrorHandling
+	// If DisableCompression is true, the handler will never compress the
+	// response, even if requested by the client.
+	DisableCompression bool
+	// The number of concurrent HTTP requests is limited to
+	// MaxRequestsInFlight. Additional requests are responded to with 503
+	// Service Unavailable and a suitable message in the body. If
+	// MaxRequestsInFlight is 0 or negative, no limit is applied.
+	MaxRequestsInFlight int
+	// If handling a request takes longer than Timeout, it is responded to
+	// with 503 ServiceUnavailable and a suitable Message. No timeout is
+	// applied if Timeout is 0 or negative. Note that with the current
+	// implementation, reaching the timeout simply ends the HTTP requests as
+	// described above (and even that only if sending of the body hasn't
+	// started yet), while the bulk work of gathering all the metrics keeps
+	// running in the background (with the eventual result to be thrown
+	// away). Until the implementation is improved, it is recommended to
+	// implement a separate timeout in potentially slow Collectors.
+	Timeout time.Duration
+}
+
+// gzipAccepted returns whether the client will accept gzip-encoded content.
+func gzipAccepted(header http.Header) bool {
+	a := header.Get(acceptEncodingHeader)
+	parts := strings.Split(a, ",")
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
+			return true
+		}
+	}
+	return false
+}
+
+// httpError removes any content-encoding header and then calls http.Error with
+// the provided error and http.StatusInternalServerErrer. Error contents is
+// supposed to be uncompressed plain text. However, same as with a plain
+// http.Error, any header settings will be void if the header has already been
+// sent. The error message will still be written to the writer, but it will
+// probably be of limited use.
+func httpError(rsp http.ResponseWriter, err error) {
+	rsp.Header().Del(contentEncodingHeader)
+	http.Error(
+		rsp,
+		"An error has occurred while serving metrics:\n\n"+err.Error(),
+		http.StatusInternalServerError,
+	)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go
new file mode 100644
index 0000000000..86fd564470
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go
@@ -0,0 +1,97 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package promhttp
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// The RoundTripperFunc type is an adapter to allow the use of ordinary
+// functions as RoundTrippers. If f is a function with the appropriate
+// signature, RountTripperFunc(f) is a RoundTripper that calls f.
+type RoundTripperFunc func(req *http.Request) (*http.Response, error)
+
+// RoundTrip implements the RoundTripper interface.
+func (rt RoundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
+	return rt(r)
+}
+
+// InstrumentRoundTripperInFlight is a middleware that wraps the provided
+// http.RoundTripper. It sets the provided prometheus.Gauge to the number of
+// requests currently handled by the wrapped http.RoundTripper.
+//
+// See the example for ExampleInstrumentRoundTripperDuration for example usage.
+func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripper) RoundTripperFunc {
+	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+		gauge.Inc()
+		defer gauge.Dec()
+		return next.RoundTrip(r)
+	})
+}
+
+// InstrumentRoundTripperCounter is a middleware that wraps the provided
+// http.RoundTripper to observe the request result with the provided CounterVec.
+// The CounterVec must have zero, one, or two non-const non-curried labels. For
+// those, the only allowed label names are "code" and "method". The function
+// panics otherwise. Partitioning of the CounterVec happens by HTTP status code
+// and/or HTTP method if the respective instance label names are present in the
+// CounterVec. For unpartitioned counting, use a CounterVec with zero labels.
+//
+// If the wrapped RoundTripper panics or returns a non-nil error, the Counter
+// is not incremented.
+//
+// See the example for ExampleInstrumentRoundTripperDuration for example usage.
+func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.RoundTripper) RoundTripperFunc {
+	code, method := checkLabels(counter)
+
+	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+		resp, err := next.RoundTrip(r)
+		if err == nil {
+			counter.With(labels(code, method, r.Method, resp.StatusCode)).Inc()
+		}
+		return resp, err
+	})
+}
+
+// InstrumentRoundTripperDuration is a middleware that wraps the provided
+// http.RoundTripper to observe the request duration with the provided
+// ObserverVec.  The ObserverVec must have zero, one, or two non-const
+// non-curried labels. For those, the only allowed label names are "code" and
+// "method". The function panics otherwise. The Observe method of the Observer
+// in the ObserverVec is called with the request duration in
+// seconds. Partitioning happens by HTTP status code and/or HTTP method if the
+// respective instance label names are present in the ObserverVec. For
+// unpartitioned observations, use an ObserverVec with zero labels. Note that
+// partitioning of Histograms is expensive and should be used judiciously.
+//
+// If the wrapped RoundTripper panics or returns a non-nil error, no values are
+// reported.
+//
+// Note that this method is only guaranteed to never observe negative durations
+// if used with Go1.9+.
+func InstrumentRoundTripperDuration(obs prometheus.ObserverVec, next http.RoundTripper) RoundTripperFunc {
+	code, method := checkLabels(obs)
+
+	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+		start := time.Now()
+		resp, err := next.RoundTrip(r)
+		if err == nil {
+			obs.With(labels(code, method, r.Method, resp.StatusCode)).Observe(time.Since(start).Seconds())
+		}
+		return resp, err
+	})
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go
new file mode 100644
index 0000000000..a034d1ec0f
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go
@@ -0,0 +1,144 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.8
+
+package promhttp
+
+import (
+	"context"
+	"crypto/tls"
+	"net/http"
+	"net/http/httptrace"
+	"time"
+)
+
+// InstrumentTrace is used to offer flexibility in instrumenting the available
+// httptrace.ClientTrace hook functions. Each function is passed a float64
+// representing the time in seconds since the start of the http request. A user
+// may choose to use separately buckets Histograms, or implement custom
+// instance labels on a per function basis.
+type InstrumentTrace struct {
+	GotConn              func(float64)
+	PutIdleConn          func(float64)
+	GotFirstResponseByte func(float64)
+	Got100Continue       func(float64)
+	DNSStart             func(float64)
+	DNSDone              func(float64)
+	ConnectStart         func(float64)
+	ConnectDone          func(float64)
+	TLSHandshakeStart    func(float64)
+	TLSHandshakeDone     func(float64)
+	WroteHeaders         func(float64)
+	Wait100Continue      func(float64)
+	WroteRequest         func(float64)
+}
+
+// InstrumentRoundTripperTrace is a middleware that wraps the provided
+// RoundTripper and reports times to hook functions provided in the
+// InstrumentTrace struct. Hook functions that are not present in the provided
+// InstrumentTrace struct are ignored. Times reported to the hook functions are
+// time since the start of the request. Only with Go1.9+, those times are
+// guaranteed to never be negative. (Earlier Go versions are not using a
+// monotonic clock.) Note that partitioning of Histograms is expensive and
+// should be used judiciously.
+//
+// For hook functions that receive an error as an argument, no observations are
+// made in the event of a non-nil error value.
+//
+// See the example for ExampleInstrumentRoundTripperDuration for example usage.
+func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) RoundTripperFunc {
+	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
+		start := time.Now()
+
+		trace := &httptrace.ClientTrace{
+			GotConn: func(_ httptrace.GotConnInfo) {
+				if it.GotConn != nil {
+					it.GotConn(time.Since(start).Seconds())
+				}
+			},
+			PutIdleConn: func(err error) {
+				if err != nil {
+					return
+				}
+				if it.PutIdleConn != nil {
+					it.PutIdleConn(time.Since(start).Seconds())
+				}
+			},
+			DNSStart: func(_ httptrace.DNSStartInfo) {
+				if it.DNSStart != nil {
+					it.DNSStart(time.Since(start).Seconds())
+				}
+			},
+			DNSDone: func(_ httptrace.DNSDoneInfo) {
+				if it.DNSDone != nil {
+					it.DNSDone(time.Since(start).Seconds())
+				}
+			},
+			ConnectStart: func(_, _ string) {
+				if it.ConnectStart != nil {
+					it.ConnectStart(time.Since(start).Seconds())
+				}
+			},
+			ConnectDone: func(_, _ string, err error) {
+				if err != nil {
+					return
+				}
+				if it.ConnectDone != nil {
+					it.ConnectDone(time.Since(start).Seconds())
+				}
+			},
+			GotFirstResponseByte: func() {
+				if it.GotFirstResponseByte != nil {
+					it.GotFirstResponseByte(time.Since(start).Seconds())
+				}
+			},
+			Got100Continue: func() {
+				if it.Got100Continue != nil {
+					it.Got100Continue(time.Since(start).Seconds())
+				}
+			},
+			TLSHandshakeStart: func() {
+				if it.TLSHandshakeStart != nil {
+					it.TLSHandshakeStart(time.Since(start).Seconds())
+				}
+			},
+			TLSHandshakeDone: func(_ tls.ConnectionState, err error) {
+				if err != nil {
+					return
+				}
+				if it.TLSHandshakeDone != nil {
+					it.TLSHandshakeDone(time.Since(start).Seconds())
+				}
+			},
+			WroteHeaders: func() {
+				if it.WroteHeaders != nil {
+					it.WroteHeaders(time.Since(start).Seconds())
+				}
+			},
+			Wait100Continue: func() {
+				if it.Wait100Continue != nil {
+					it.Wait100Continue(time.Since(start).Seconds())
+				}
+			},
+			WroteRequest: func(_ httptrace.WroteRequestInfo) {
+				if it.WroteRequest != nil {
+					it.WroteRequest(time.Since(start).Seconds())
+				}
+			},
+		}
+		r = r.WithContext(httptrace.WithClientTrace(context.Background(), trace))
+
+		return next.RoundTrip(r)
+	})
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go
new file mode 100644
index 0000000000..9db2438053
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go
@@ -0,0 +1,447 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package promhttp
+
+import (
+	"errors"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// magicString is used for the hacky label test in checkLabels. Remove once fixed.
+const magicString = "zZgWfBxLqvG8kc8IMv3POi2Bb0tZI3vAnBx+gBaFi9FyPzB/CzKUer1yufDa"
+
+// InstrumentHandlerInFlight is a middleware that wraps the provided
+// http.Handler. It sets the provided prometheus.Gauge to the number of
+// requests currently handled by the wrapped http.Handler.
+//
+// See the example for InstrumentHandlerDuration for example usage.
+func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		g.Inc()
+		defer g.Dec()
+		next.ServeHTTP(w, r)
+	})
+}
+
+// InstrumentHandlerDuration is a middleware that wraps the provided
+// http.Handler to observe the request duration with the provided ObserverVec.
+// The ObserverVec must have zero, one, or two non-const non-curried labels. For
+// those, the only allowed label names are "code" and "method". The function
+// panics otherwise. The Observe method of the Observer in the ObserverVec is
+// called with the request duration in seconds. Partitioning happens by HTTP
+// status code and/or HTTP method if the respective instance label names are
+// present in the ObserverVec. For unpartitioned observations, use an
+// ObserverVec with zero labels. Note that partitioning of Histograms is
+// expensive and should be used judiciously.
+//
+// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
+//
+// If the wrapped Handler panics, no values are reported.
+//
+// Note that this method is only guaranteed to never observe negative durations
+// if used with Go1.9+.
+func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
+	code, method := checkLabels(obs)
+
+	if code {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			now := time.Now()
+			d := newDelegator(w, nil)
+			next.ServeHTTP(d, r)
+
+			obs.With(labels(code, method, r.Method, d.Status())).Observe(time.Since(now).Seconds())
+		})
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		now := time.Now()
+		next.ServeHTTP(w, r)
+		obs.With(labels(code, method, r.Method, 0)).Observe(time.Since(now).Seconds())
+	})
+}
+
+// InstrumentHandlerCounter is a middleware that wraps the provided http.Handler
+// to observe the request result with the provided CounterVec.  The CounterVec
+// must have zero, one, or two non-const non-curried labels. For those, the only
+// allowed label names are "code" and "method". The function panics
+// otherwise. Partitioning of the CounterVec happens by HTTP status code and/or
+// HTTP method if the respective instance label names are present in the
+// CounterVec. For unpartitioned counting, use a CounterVec with zero labels.
+//
+// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
+//
+// If the wrapped Handler panics, the Counter is not incremented.
+//
+// See the example for InstrumentHandlerDuration for example usage.
+func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc {
+	code, method := checkLabels(counter)
+
+	if code {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			d := newDelegator(w, nil)
+			next.ServeHTTP(d, r)
+			counter.With(labels(code, method, r.Method, d.Status())).Inc()
+		})
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		next.ServeHTTP(w, r)
+		counter.With(labels(code, method, r.Method, 0)).Inc()
+	})
+}
+
+// InstrumentHandlerTimeToWriteHeader is a middleware that wraps the provided
+// http.Handler to observe with the provided ObserverVec the request duration
+// until the response headers are written. The ObserverVec must have zero, one,
+// or two non-const non-curried labels. For those, the only allowed label names
+// are "code" and "method". The function panics otherwise. The Observe method of
+// the Observer in the ObserverVec is called with the request duration in
+// seconds. Partitioning happens by HTTP status code and/or HTTP method if the
+// respective instance label names are present in the ObserverVec. For
+// unpartitioned observations, use an ObserverVec with zero labels. Note that
+// partitioning of Histograms is expensive and should be used judiciously.
+//
+// If the wrapped Handler panics before calling WriteHeader, no value is
+// reported.
+//
+// Note that this method is only guaranteed to never observe negative durations
+// if used with Go1.9+.
+//
+// See the example for InstrumentHandlerDuration for example usage.
+func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
+	code, method := checkLabels(obs)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		now := time.Now()
+		d := newDelegator(w, func(status int) {
+			obs.With(labels(code, method, r.Method, status)).Observe(time.Since(now).Seconds())
+		})
+		next.ServeHTTP(d, r)
+	})
+}
+
+// InstrumentHandlerRequestSize is a middleware that wraps the provided
+// http.Handler to observe the request size with the provided ObserverVec.  The
+// ObserverVec must have zero, one, or two non-const non-curried labels. For
+// those, the only allowed label names are "code" and "method". The function
+// panics otherwise. The Observe method of the Observer in the ObserverVec is
+// called with the request size in bytes. Partitioning happens by HTTP status
+// code and/or HTTP method if the respective instance label names are present in
+// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero
+// labels. Note that partitioning of Histograms is expensive and should be used
+// judiciously.
+//
+// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
+//
+// If the wrapped Handler panics, no values are reported.
+//
+// See the example for InstrumentHandlerDuration for example usage.
+func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
+	code, method := checkLabels(obs)
+
+	if code {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			d := newDelegator(w, nil)
+			next.ServeHTTP(d, r)
+			size := computeApproximateRequestSize(r)
+			obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(size))
+		})
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		next.ServeHTTP(w, r)
+		size := computeApproximateRequestSize(r)
+		obs.With(labels(code, method, r.Method, 0)).Observe(float64(size))
+	})
+}
+
+// InstrumentHandlerResponseSize is a middleware that wraps the provided
+// http.Handler to observe the response size with the provided ObserverVec.  The
+// ObserverVec must have zero, one, or two non-const non-curried labels. For
+// those, the only allowed label names are "code" and "method". The function
+// panics otherwise. The Observe method of the Observer in the ObserverVec is
+// called with the response size in bytes. Partitioning happens by HTTP status
+// code and/or HTTP method if the respective instance label names are present in
+// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero
+// labels. Note that partitioning of Histograms is expensive and should be used
+// judiciously.
+//
+// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
+//
+// If the wrapped Handler panics, no values are reported.
+//
+// See the example for InstrumentHandlerDuration for example usage.
+func InstrumentHandlerResponseSize(obs prometheus.ObserverVec, next http.Handler) http.Handler {
+	code, method := checkLabels(obs)
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		d := newDelegator(w, nil)
+		next.ServeHTTP(d, r)
+		obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(d.Written()))
+	})
+}
+
+func checkLabels(c prometheus.Collector) (code bool, method bool) {
+	// TODO(beorn7): Remove this hacky way to check for instance labels
+	// once Descriptors can have their dimensionality queried.
+	var (
+		desc *prometheus.Desc
+		m    prometheus.Metric
+		pm   dto.Metric
+		lvs  []string
+	)
+
+	// Get the Desc from the Collector.
+	descc := make(chan *prometheus.Desc, 1)
+	c.Describe(descc)
+
+	select {
+	case desc = <-descc:
+	default:
+		panic("no description provided by collector")
+	}
+	select {
+	case <-descc:
+		panic("more than one description provided by collector")
+	default:
+	}
+
+	close(descc)
+
+	// Create a ConstMetric with the Desc. Since we don't know how many
+	// variable labels there are, try for as long as it needs.
+	for err := errors.New("dummy"); err != nil; lvs = append(lvs, magicString) {
+		m, err = prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, lvs...)
+	}
+
+	// Write out the metric into a proto message and look at the labels.
+	// If the value is not the magicString, it is a constLabel, which doesn't interest us.
+	// If the label is curried, it doesn't interest us.
+	// In all other cases, only "code" or "method" is allowed.
+	if err := m.Write(&pm); err != nil {
+		panic("error checking metric for labels")
+	}
+	for _, label := range pm.Label {
+		name, value := label.GetName(), label.GetValue()
+		if value != magicString || isLabelCurried(c, name) {
+			continue
+		}
+		switch name {
+		case "code":
+			code = true
+		case "method":
+			method = true
+		default:
+			panic("metric partitioned with non-supported labels")
+		}
+	}
+	return
+}
+
+func isLabelCurried(c prometheus.Collector, label string) bool {
+	// This is even hackier than the label test above.
+	// We essentially try to curry again and see if it works.
+	// But for that, we need to type-convert to the two
+	// types we use here, ObserverVec or *CounterVec.
+	switch v := c.(type) {
+	case *prometheus.CounterVec:
+		if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil {
+			return false
+		}
+	case prometheus.ObserverVec:
+		if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil {
+			return false
+		}
+	default:
+		panic("unsupported metric vec type")
+	}
+	return true
+}
+
+// emptyLabels is a one-time allocation for non-partitioned metrics to avoid
+// unnecessary allocations on each request.
+var emptyLabels = prometheus.Labels{}
+
+func labels(code, method bool, reqMethod string, status int) prometheus.Labels {
+	if !(code || method) {
+		return emptyLabels
+	}
+	labels := prometheus.Labels{}
+
+	if code {
+		labels["code"] = sanitizeCode(status)
+	}
+	if method {
+		labels["method"] = sanitizeMethod(reqMethod)
+	}
+
+	return labels
+}
+
+func computeApproximateRequestSize(r *http.Request) int {
+	s := 0
+	if r.URL != nil {
+		s += len(r.URL.String())
+	}
+
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
+		}
+	}
+	s += len(r.Host)
+
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
+
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	return s
+}
+
+func sanitizeMethod(m string) string {
+	switch m {
+	case "GET", "get":
+		return "get"
+	case "PUT", "put":
+		return "put"
+	case "HEAD", "head":
+		return "head"
+	case "POST", "post":
+		return "post"
+	case "DELETE", "delete":
+		return "delete"
+	case "CONNECT", "connect":
+		return "connect"
+	case "OPTIONS", "options":
+		return "options"
+	case "NOTIFY", "notify":
+		return "notify"
+	default:
+		return strings.ToLower(m)
+	}
+}
+
+// If the wrapped http.Handler has not set a status code, i.e. the value is
+// currently 0, santizeCode will return 200, for consistency with behavior in
+// the stdlib.
+func sanitizeCode(s int) string {
+	switch s {
+	case 100:
+		return "100"
+	case 101:
+		return "101"
+
+	case 200, 0:
+		return "200"
+	case 201:
+		return "201"
+	case 202:
+		return "202"
+	case 203:
+		return "203"
+	case 204:
+		return "204"
+	case 205:
+		return "205"
+	case 206:
+		return "206"
+
+	case 300:
+		return "300"
+	case 301:
+		return "301"
+	case 302:
+		return "302"
+	case 304:
+		return "304"
+	case 305:
+		return "305"
+	case 307:
+		return "307"
+
+	case 400:
+		return "400"
+	case 401:
+		return "401"
+	case 402:
+		return "402"
+	case 403:
+		return "403"
+	case 404:
+		return "404"
+	case 405:
+		return "405"
+	case 406:
+		return "406"
+	case 407:
+		return "407"
+	case 408:
+		return "408"
+	case 409:
+		return "409"
+	case 410:
+		return "410"
+	case 411:
+		return "411"
+	case 412:
+		return "412"
+	case 413:
+		return "413"
+	case 414:
+		return "414"
+	case 415:
+		return "415"
+	case 416:
+		return "416"
+	case 417:
+		return "417"
+	case 418:
+		return "418"
+
+	case 500:
+		return "500"
+	case 501:
+		return "501"
+	case 502:
+		return "502"
+	case 503:
+		return "503"
+	case 504:
+		return "504"
+	case 505:
+		return "505"
+
+	case 428:
+		return "428"
+	case 429:
+		return "429"
+	case 431:
+		return "431"
+	case 511:
+		return "511"
+
+	default:
+		return strconv.Itoa(s)
+	}
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/registry.go b/vendor/github.com/prometheus/client_golang/prometheus/registry.go
new file mode 100644
index 0000000000..b5e70b93fa
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/registry.go
@@ -0,0 +1,937 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sort"
+	"strings"
+	"sync"
+	"unicode/utf8"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/expfmt"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus/internal"
+)
+
+const (
+	// Capacity for the channel to collect metrics and descriptors.
+	capMetricChan = 1000
+	capDescChan   = 10
+)
+
+// DefaultRegisterer and DefaultGatherer are the implementations of the
+// Registerer and Gatherer interface a number of convenience functions in this
+// package act on. Initially, both variables point to the same Registry, which
+// has a process collector (currently on Linux only, see NewProcessCollector)
+// and a Go collector (see NewGoCollector, in particular the note about
+// stop-the-world implication with Go versions older than 1.9) already
+// registered. This approach to keep default instances as global state mirrors
+// the approach of other packages in the Go standard library. Note that there
+// are caveats. Change the variables with caution and only if you understand the
+// consequences. Users who want to avoid global state altogether should not use
+// the convenience functions and act on custom instances instead.
+var (
+	defaultRegistry              = NewRegistry()
+	DefaultRegisterer Registerer = defaultRegistry
+	DefaultGatherer   Gatherer   = defaultRegistry
+)
+
+func init() {
+	MustRegister(NewProcessCollector(ProcessCollectorOpts{}))
+	MustRegister(NewGoCollector())
+}
+
+// NewRegistry creates a new vanilla Registry without any Collectors
+// pre-registered.
+func NewRegistry() *Registry {
+	return &Registry{
+		collectorsByID:  map[uint64]Collector{},
+		descIDs:         map[uint64]struct{}{},
+		dimHashesByName: map[string]uint64{},
+	}
+}
+
+// NewPedanticRegistry returns a registry that checks during collection if each
+// collected Metric is consistent with its reported Desc, and if the Desc has
+// actually been registered with the registry. Unchecked Collectors (those whose
+// Describe methed does not yield any descriptors) are excluded from the check.
+//
+// Usually, a Registry will be happy as long as the union of all collected
+// Metrics is consistent and valid even if some metrics are not consistent with
+// their own Desc or a Desc provided by their registered Collector. Well-behaved
+// Collectors and Metrics will only provide consistent Descs. This Registry is
+// useful to test the implementation of Collectors and Metrics.
+func NewPedanticRegistry() *Registry {
+	r := NewRegistry()
+	r.pedanticChecksEnabled = true
+	return r
+}
+
+// Registerer is the interface for the part of a registry in charge of
+// registering and unregistering. Users of custom registries should use
+// Registerer as type for registration purposes (rather than the Registry type
+// directly). In that way, they are free to use custom Registerer implementation
+// (e.g. for testing purposes).
+type Registerer interface {
+	// Register registers a new Collector to be included in metrics
+	// collection. It returns an error if the descriptors provided by the
+	// Collector are invalid or if they — in combination with descriptors of
+	// already registered Collectors — do not fulfill the consistency and
+	// uniqueness criteria described in the documentation of metric.Desc.
+	//
+	// If the provided Collector is equal to a Collector already registered
+	// (which includes the case of re-registering the same Collector), the
+	// returned error is an instance of AlreadyRegisteredError, which
+	// contains the previously registered Collector.
+	//
+	// A Collector whose Describe method does not yield any Desc is treated
+	// as unchecked. Registration will always succeed. No check for
+	// re-registering (see previous paragraph) is performed. Thus, the
+	// caller is responsible for not double-registering the same unchecked
+	// Collector, and for providing a Collector that will not cause
+	// inconsistent metrics on collection. (This would lead to scrape
+	// errors.)
+	Register(Collector) error
+	// MustRegister works like Register but registers any number of
+	// Collectors and panics upon the first registration that causes an
+	// error.
+	MustRegister(...Collector)
+	// Unregister unregisters the Collector that equals the Collector passed
+	// in as an argument.  (Two Collectors are considered equal if their
+	// Describe method yields the same set of descriptors.) The function
+	// returns whether a Collector was unregistered. Note that an unchecked
+	// Collector cannot be unregistered (as its Describe method does not
+	// yield any descriptor).
+	//
+	// Note that even after unregistering, it will not be possible to
+	// register a new Collector that is inconsistent with the unregistered
+	// Collector, e.g. a Collector collecting metrics with the same name but
+	// a different help string. The rationale here is that the same registry
+	// instance must only collect consistent metrics throughout its
+	// lifetime.
+	Unregister(Collector) bool
+}
+
+// Gatherer is the interface for the part of a registry in charge of gathering
+// the collected metrics into a number of MetricFamilies. The Gatherer interface
+// comes with the same general implication as described for the Registerer
+// interface.
+type Gatherer interface {
+	// Gather calls the Collect method of the registered Collectors and then
+	// gathers the collected metrics into a lexicographically sorted slice
+	// of uniquely named MetricFamily protobufs. Gather ensures that the
+	// returned slice is valid and self-consistent so that it can be used
+	// for valid exposition. As an exception to the strict consistency
+	// requirements described for metric.Desc, Gather will tolerate
+	// different sets of label names for metrics of the same metric family.
+	//
+	// Even if an error occurs, Gather attempts to gather as many metrics as
+	// possible. Hence, if a non-nil error is returned, the returned
+	// MetricFamily slice could be nil (in case of a fatal error that
+	// prevented any meaningful metric collection) or contain a number of
+	// MetricFamily protobufs, some of which might be incomplete, and some
+	// might be missing altogether. The returned error (which might be a
+	// MultiError) explains the details. Note that this is mostly useful for
+	// debugging purposes. If the gathered protobufs are to be used for
+	// exposition in actual monitoring, it is almost always better to not
+	// expose an incomplete result and instead disregard the returned
+	// MetricFamily protobufs in case the returned error is non-nil.
+	Gather() ([]*dto.MetricFamily, error)
+}
+
+// Register registers the provided Collector with the DefaultRegisterer.
+//
+// Register is a shortcut for DefaultRegisterer.Register(c). See there for more
+// details.
+func Register(c Collector) error {
+	return DefaultRegisterer.Register(c)
+}
+
+// MustRegister registers the provided Collectors with the DefaultRegisterer and
+// panics if any error occurs.
+//
+// MustRegister is a shortcut for DefaultRegisterer.MustRegister(cs...). See
+// there for more details.
+func MustRegister(cs ...Collector) {
+	DefaultRegisterer.MustRegister(cs...)
+}
+
+// Unregister removes the registration of the provided Collector from the
+// DefaultRegisterer.
+//
+// Unregister is a shortcut for DefaultRegisterer.Unregister(c). See there for
+// more details.
+func Unregister(c Collector) bool {
+	return DefaultRegisterer.Unregister(c)
+}
+
+// GathererFunc turns a function into a Gatherer.
+type GathererFunc func() ([]*dto.MetricFamily, error)
+
+// Gather implements Gatherer.
+func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) {
+	return gf()
+}
+
+// AlreadyRegisteredError is returned by the Register method if the Collector to
+// be registered has already been registered before, or a different Collector
+// that collects the same metrics has been registered before. Registration fails
+// in that case, but you can detect from the kind of error what has
+// happened. The error contains fields for the existing Collector and the
+// (rejected) new Collector that equals the existing one. This can be used to
+// find out if an equal Collector has been registered before and switch over to
+// using the old one, as demonstrated in the example.
+type AlreadyRegisteredError struct {
+	ExistingCollector, NewCollector Collector
+}
+
+func (err AlreadyRegisteredError) Error() string {
+	return "duplicate metrics collector registration attempted"
+}
+
+// MultiError is a slice of errors implementing the error interface. It is used
+// by a Gatherer to report multiple errors during MetricFamily gathering.
+type MultiError []error
+
+func (errs MultiError) Error() string {
+	if len(errs) == 0 {
+		return ""
+	}
+	buf := &bytes.Buffer{}
+	fmt.Fprintf(buf, "%d error(s) occurred:", len(errs))
+	for _, err := range errs {
+		fmt.Fprintf(buf, "\n* %s", err)
+	}
+	return buf.String()
+}
+
+// Append appends the provided error if it is not nil.
+func (errs *MultiError) Append(err error) {
+	if err != nil {
+		*errs = append(*errs, err)
+	}
+}
+
+// MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only
+// contained error as error if len(errs is 1). In all other cases, it returns
+// the MultiError directly. This is helpful for returning a MultiError in a way
+// that only uses the MultiError if needed.
+func (errs MultiError) MaybeUnwrap() error {
+	switch len(errs) {
+	case 0:
+		return nil
+	case 1:
+		return errs[0]
+	default:
+		return errs
+	}
+}
+
+// Registry registers Prometheus collectors, collects their metrics, and gathers
+// them into MetricFamilies for exposition. It implements both Registerer and
+// Gatherer. The zero value is not usable. Create instances with NewRegistry or
+// NewPedanticRegistry.
+type Registry struct {
+	mtx                   sync.RWMutex
+	collectorsByID        map[uint64]Collector // ID is a hash of the descIDs.
+	descIDs               map[uint64]struct{}
+	dimHashesByName       map[string]uint64
+	uncheckedCollectors   []Collector
+	pedanticChecksEnabled bool
+}
+
+// Register implements Registerer.
+func (r *Registry) Register(c Collector) error {
+	var (
+		descChan           = make(chan *Desc, capDescChan)
+		newDescIDs         = map[uint64]struct{}{}
+		newDimHashesByName = map[string]uint64{}
+		collectorID        uint64 // Just a sum of all desc IDs.
+		duplicateDescErr   error
+	)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+	r.mtx.Lock()
+	defer func() {
+		// Drain channel in case of premature return to not leak a goroutine.
+		for range descChan {
+		}
+		r.mtx.Unlock()
+	}()
+	// Conduct various tests...
+	for desc := range descChan {
+
+		// Is the descriptor valid at all?
+		if desc.err != nil {
+			return fmt.Errorf("descriptor %s is invalid: %s", desc, desc.err)
+		}
+
+		// Is the descID unique?
+		// (In other words: Is the fqName + constLabel combination unique?)
+		if _, exists := r.descIDs[desc.id]; exists {
+			duplicateDescErr = fmt.Errorf("descriptor %s already exists with the same fully-qualified name and const label values", desc)
+		}
+		// If it is not a duplicate desc in this collector, add it to
+		// the collectorID.  (We allow duplicate descs within the same
+		// collector, but their existence must be a no-op.)
+		if _, exists := newDescIDs[desc.id]; !exists {
+			newDescIDs[desc.id] = struct{}{}
+			collectorID += desc.id
+		}
+
+		// Are all the label names and the help string consistent with
+		// previous descriptors of the same name?
+		// First check existing descriptors...
+		if dimHash, exists := r.dimHashesByName[desc.fqName]; exists {
+			if dimHash != desc.dimHash {
+				return fmt.Errorf("a previously registered descriptor with the same fully-qualified name as %s has different label names or a different help string", desc)
+			}
+		} else {
+			// ...then check the new descriptors already seen.
+			if dimHash, exists := newDimHashesByName[desc.fqName]; exists {
+				if dimHash != desc.dimHash {
+					return fmt.Errorf("descriptors reported by collector have inconsistent label names or help strings for the same fully-qualified name, offender is %s", desc)
+				}
+			} else {
+				newDimHashesByName[desc.fqName] = desc.dimHash
+			}
+		}
+	}
+	// A Collector yielding no Desc at all is considered unchecked.
+	if len(newDescIDs) == 0 {
+		r.uncheckedCollectors = append(r.uncheckedCollectors, c)
+		return nil
+	}
+	if existing, exists := r.collectorsByID[collectorID]; exists {
+		return AlreadyRegisteredError{
+			ExistingCollector: existing,
+			NewCollector:      c,
+		}
+	}
+	// If the collectorID is new, but at least one of the descs existed
+	// before, we are in trouble.
+	if duplicateDescErr != nil {
+		return duplicateDescErr
+	}
+
+	// Only after all tests have passed, actually register.
+	r.collectorsByID[collectorID] = c
+	for hash := range newDescIDs {
+		r.descIDs[hash] = struct{}{}
+	}
+	for name, dimHash := range newDimHashesByName {
+		r.dimHashesByName[name] = dimHash
+	}
+	return nil
+}
+
+// Unregister implements Registerer.
+func (r *Registry) Unregister(c Collector) bool {
+	var (
+		descChan    = make(chan *Desc, capDescChan)
+		descIDs     = map[uint64]struct{}{}
+		collectorID uint64 // Just a sum of the desc IDs.
+	)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+	for desc := range descChan {
+		if _, exists := descIDs[desc.id]; !exists {
+			collectorID += desc.id
+			descIDs[desc.id] = struct{}{}
+		}
+	}
+
+	r.mtx.RLock()
+	if _, exists := r.collectorsByID[collectorID]; !exists {
+		r.mtx.RUnlock()
+		return false
+	}
+	r.mtx.RUnlock()
+
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+
+	delete(r.collectorsByID, collectorID)
+	for id := range descIDs {
+		delete(r.descIDs, id)
+	}
+	// dimHashesByName is left untouched as those must be consistent
+	// throughout the lifetime of a program.
+	return true
+}
+
+// MustRegister implements Registerer.
+func (r *Registry) MustRegister(cs ...Collector) {
+	for _, c := range cs {
+		if err := r.Register(c); err != nil {
+			panic(err)
+		}
+	}
+}
+
+// Gather implements Gatherer.
+func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
+	var (
+		checkedMetricChan   = make(chan Metric, capMetricChan)
+		uncheckedMetricChan = make(chan Metric, capMetricChan)
+		metricHashes        = map[uint64]struct{}{}
+		wg                  sync.WaitGroup
+		errs                MultiError          // The collected errors to return in the end.
+		registeredDescIDs   map[uint64]struct{} // Only used for pedantic checks
+	)
+
+	r.mtx.RLock()
+	goroutineBudget := len(r.collectorsByID) + len(r.uncheckedCollectors)
+	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
+	checkedCollectors := make(chan Collector, len(r.collectorsByID))
+	uncheckedCollectors := make(chan Collector, len(r.uncheckedCollectors))
+	for _, collector := range r.collectorsByID {
+		checkedCollectors <- collector
+	}
+	for _, collector := range r.uncheckedCollectors {
+		uncheckedCollectors <- collector
+	}
+	// In case pedantic checks are enabled, we have to copy the map before
+	// giving up the RLock.
+	if r.pedanticChecksEnabled {
+		registeredDescIDs = make(map[uint64]struct{}, len(r.descIDs))
+		for id := range r.descIDs {
+			registeredDescIDs[id] = struct{}{}
+		}
+	}
+	r.mtx.RUnlock()
+
+	wg.Add(goroutineBudget)
+
+	collectWorker := func() {
+		for {
+			select {
+			case collector := <-checkedCollectors:
+				collector.Collect(checkedMetricChan)
+			case collector := <-uncheckedCollectors:
+				collector.Collect(uncheckedMetricChan)
+			default:
+				return
+			}
+			wg.Done()
+		}
+	}
+
+	// Start the first worker now to make sure at least one is running.
+	go collectWorker()
+	goroutineBudget--
+
+	// Close checkedMetricChan and uncheckedMetricChan once all collectors
+	// are collected.
+	go func() {
+		wg.Wait()
+		close(checkedMetricChan)
+		close(uncheckedMetricChan)
+	}()
+
+	// Drain checkedMetricChan and uncheckedMetricChan in case of premature return.
+	defer func() {
+		if checkedMetricChan != nil {
+			for range checkedMetricChan {
+			}
+		}
+		if uncheckedMetricChan != nil {
+			for range uncheckedMetricChan {
+			}
+		}
+	}()
+
+	// Copy the channel references so we can nil them out later to remove
+	// them from the select statements below.
+	cmc := checkedMetricChan
+	umc := uncheckedMetricChan
+
+	for {
+		select {
+		case metric, ok := <-cmc:
+			if !ok {
+				cmc = nil
+				break
+			}
+			errs.Append(processMetric(
+				metric, metricFamiliesByName,
+				metricHashes,
+				registeredDescIDs,
+			))
+		case metric, ok := <-umc:
+			if !ok {
+				umc = nil
+				break
+			}
+			errs.Append(processMetric(
+				metric, metricFamiliesByName,
+				metricHashes,
+				nil,
+			))
+		default:
+			if goroutineBudget <= 0 || len(checkedCollectors)+len(uncheckedCollectors) == 0 {
+				// All collectors are already being worked on or
+				// we have already as many goroutines started as
+				// there are collectors. Do the same as above,
+				// just without the default.
+				select {
+				case metric, ok := <-cmc:
+					if !ok {
+						cmc = nil
+						break
+					}
+					errs.Append(processMetric(
+						metric, metricFamiliesByName,
+						metricHashes,
+						registeredDescIDs,
+					))
+				case metric, ok := <-umc:
+					if !ok {
+						umc = nil
+						break
+					}
+					errs.Append(processMetric(
+						metric, metricFamiliesByName,
+						metricHashes,
+						nil,
+					))
+				}
+				break
+			}
+			// Start more workers.
+			go collectWorker()
+			goroutineBudget--
+			runtime.Gosched()
+		}
+		// Once both checkedMetricChan and uncheckdMetricChan are closed
+		// and drained, the contraption above will nil out cmc and umc,
+		// and then we can leave the collect loop here.
+		if cmc == nil && umc == nil {
+			break
+		}
+	}
+	return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+}
+
+// WriteToTextfile calls Gather on the provided Gatherer, encodes the result in the
+// Prometheus text format, and writes it to a temporary file. Upon success, the
+// temporary file is renamed to the provided filename.
+//
+// This is intended for use with the textfile collector of the node exporter.
+// Note that the node exporter expects the filename to be suffixed with ".prom".
+func WriteToTextfile(filename string, g Gatherer) error {
+	tmp, err := ioutil.TempFile(filepath.Dir(filename), filepath.Base(filename))
+	if err != nil {
+		return err
+	}
+	defer os.Remove(tmp.Name())
+
+	mfs, err := g.Gather()
+	if err != nil {
+		return err
+	}
+	for _, mf := range mfs {
+		if _, err := expfmt.MetricFamilyToText(tmp, mf); err != nil {
+			return err
+		}
+	}
+	if err := tmp.Close(); err != nil {
+		return err
+	}
+
+	if err := os.Chmod(tmp.Name(), 0644); err != nil {
+		return err
+	}
+	return os.Rename(tmp.Name(), filename)
+}
+
+// processMetric is an internal helper method only used by the Gather method.
+func processMetric(
+	metric Metric,
+	metricFamiliesByName map[string]*dto.MetricFamily,
+	metricHashes map[uint64]struct{},
+	registeredDescIDs map[uint64]struct{},
+) error {
+	desc := metric.Desc()
+	// Wrapped metrics collected by an unchecked Collector can have an
+	// invalid Desc.
+	if desc.err != nil {
+		return desc.err
+	}
+	dtoMetric := &dto.Metric{}
+	if err := metric.Write(dtoMetric); err != nil {
+		return fmt.Errorf("error collecting metric %v: %s", desc, err)
+	}
+	metricFamily, ok := metricFamiliesByName[desc.fqName]
+	if ok { // Existing name.
+		if metricFamily.GetHelp() != desc.help {
+			return fmt.Errorf(
+				"collected metric %s %s has help %q but should have %q",
+				desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
+			)
+		}
+		// TODO(beorn7): Simplify switch once Desc has type.
+		switch metricFamily.GetType() {
+		case dto.MetricType_COUNTER:
+			if dtoMetric.Counter == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Counter",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_GAUGE:
+			if dtoMetric.Gauge == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Gauge",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_SUMMARY:
+			if dtoMetric.Summary == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Summary",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_UNTYPED:
+			if dtoMetric.Untyped == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be Untyped",
+					desc.fqName, dtoMetric,
+				)
+			}
+		case dto.MetricType_HISTOGRAM:
+			if dtoMetric.Histogram == nil {
+				return fmt.Errorf(
+					"collected metric %s %s should be a Histogram",
+					desc.fqName, dtoMetric,
+				)
+			}
+		default:
+			panic("encountered MetricFamily with invalid type")
+		}
+	} else { // New name.
+		metricFamily = &dto.MetricFamily{}
+		metricFamily.Name = proto.String(desc.fqName)
+		metricFamily.Help = proto.String(desc.help)
+		// TODO(beorn7): Simplify switch once Desc has type.
+		switch {
+		case dtoMetric.Gauge != nil:
+			metricFamily.Type = dto.MetricType_GAUGE.Enum()
+		case dtoMetric.Counter != nil:
+			metricFamily.Type = dto.MetricType_COUNTER.Enum()
+		case dtoMetric.Summary != nil:
+			metricFamily.Type = dto.MetricType_SUMMARY.Enum()
+		case dtoMetric.Untyped != nil:
+			metricFamily.Type = dto.MetricType_UNTYPED.Enum()
+		case dtoMetric.Histogram != nil:
+			metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
+		default:
+			return fmt.Errorf("empty metric collected: %s", dtoMetric)
+		}
+		if err := checkSuffixCollisions(metricFamily, metricFamiliesByName); err != nil {
+			return err
+		}
+		metricFamiliesByName[desc.fqName] = metricFamily
+	}
+	if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes); err != nil {
+		return err
+	}
+	if registeredDescIDs != nil {
+		// Is the desc registered at all?
+		if _, exist := registeredDescIDs[desc.id]; !exist {
+			return fmt.Errorf(
+				"collected metric %s %s with unregistered descriptor %s",
+				metricFamily.GetName(), dtoMetric, desc,
+			)
+		}
+		if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
+			return err
+		}
+	}
+	metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
+	return nil
+}
+
+// Gatherers is a slice of Gatherer instances that implements the Gatherer
+// interface itself. Its Gather method calls Gather on all Gatherers in the
+// slice in order and returns the merged results. Errors returned from the
+// Gather calles are all returned in a flattened MultiError. Duplicate and
+// inconsistent Metrics are skipped (first occurrence in slice order wins) and
+// reported in the returned error.
+//
+// Gatherers can be used to merge the Gather results from multiple
+// Registries. It also provides a way to directly inject existing MetricFamily
+// protobufs into the gathering by creating a custom Gatherer with a Gather
+// method that simply returns the existing MetricFamily protobufs. Note that no
+// registration is involved (in contrast to Collector registration), so
+// obviously registration-time checks cannot happen. Any inconsistencies between
+// the gathered MetricFamilies are reported as errors by the Gather method, and
+// inconsistent Metrics are dropped. Invalid parts of the MetricFamilies
+// (e.g. syntactically invalid metric or label names) will go undetected.
+type Gatherers []Gatherer
+
+// Gather implements Gatherer.
+func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
+	var (
+		metricFamiliesByName = map[string]*dto.MetricFamily{}
+		metricHashes         = map[uint64]struct{}{}
+		errs                 MultiError // The collected errors to return in the end.
+	)
+
+	for i, g := range gs {
+		mfs, err := g.Gather()
+		if err != nil {
+			if multiErr, ok := err.(MultiError); ok {
+				for _, err := range multiErr {
+					errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
+				}
+			} else {
+				errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
+			}
+		}
+		for _, mf := range mfs {
+			existingMF, exists := metricFamiliesByName[mf.GetName()]
+			if exists {
+				if existingMF.GetHelp() != mf.GetHelp() {
+					errs = append(errs, fmt.Errorf(
+						"gathered metric family %s has help %q but should have %q",
+						mf.GetName(), mf.GetHelp(), existingMF.GetHelp(),
+					))
+					continue
+				}
+				if existingMF.GetType() != mf.GetType() {
+					errs = append(errs, fmt.Errorf(
+						"gathered metric family %s has type %s but should have %s",
+						mf.GetName(), mf.GetType(), existingMF.GetType(),
+					))
+					continue
+				}
+			} else {
+				existingMF = &dto.MetricFamily{}
+				existingMF.Name = mf.Name
+				existingMF.Help = mf.Help
+				existingMF.Type = mf.Type
+				if err := checkSuffixCollisions(existingMF, metricFamiliesByName); err != nil {
+					errs = append(errs, err)
+					continue
+				}
+				metricFamiliesByName[mf.GetName()] = existingMF
+			}
+			for _, m := range mf.Metric {
+				if err := checkMetricConsistency(existingMF, m, metricHashes); err != nil {
+					errs = append(errs, err)
+					continue
+				}
+				existingMF.Metric = append(existingMF.Metric, m)
+			}
+		}
+	}
+	return internal.NormalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+}
+
+// checkSuffixCollisions checks for collisions with the “magic” suffixes the
+// Prometheus text format and the internal metric representation of the
+// Prometheus server add while flattening Summaries and Histograms.
+func checkSuffixCollisions(mf *dto.MetricFamily, mfs map[string]*dto.MetricFamily) error {
+	var (
+		newName              = mf.GetName()
+		newType              = mf.GetType()
+		newNameWithoutSuffix = ""
+	)
+	switch {
+	case strings.HasSuffix(newName, "_count"):
+		newNameWithoutSuffix = newName[:len(newName)-6]
+	case strings.HasSuffix(newName, "_sum"):
+		newNameWithoutSuffix = newName[:len(newName)-4]
+	case strings.HasSuffix(newName, "_bucket"):
+		newNameWithoutSuffix = newName[:len(newName)-7]
+	}
+	if newNameWithoutSuffix != "" {
+		if existingMF, ok := mfs[newNameWithoutSuffix]; ok {
+			switch existingMF.GetType() {
+			case dto.MetricType_SUMMARY:
+				if !strings.HasSuffix(newName, "_bucket") {
+					return fmt.Errorf(
+						"collected metric named %q collides with previously collected summary named %q",
+						newName, newNameWithoutSuffix,
+					)
+				}
+			case dto.MetricType_HISTOGRAM:
+				return fmt.Errorf(
+					"collected metric named %q collides with previously collected histogram named %q",
+					newName, newNameWithoutSuffix,
+				)
+			}
+		}
+	}
+	if newType == dto.MetricType_SUMMARY || newType == dto.MetricType_HISTOGRAM {
+		if _, ok := mfs[newName+"_count"]; ok {
+			return fmt.Errorf(
+				"collected histogram or summary named %q collides with previously collected metric named %q",
+				newName, newName+"_count",
+			)
+		}
+		if _, ok := mfs[newName+"_sum"]; ok {
+			return fmt.Errorf(
+				"collected histogram or summary named %q collides with previously collected metric named %q",
+				newName, newName+"_sum",
+			)
+		}
+	}
+	if newType == dto.MetricType_HISTOGRAM {
+		if _, ok := mfs[newName+"_bucket"]; ok {
+			return fmt.Errorf(
+				"collected histogram named %q collides with previously collected metric named %q",
+				newName, newName+"_bucket",
+			)
+		}
+	}
+	return nil
+}
+
+// checkMetricConsistency checks if the provided Metric is consistent with the
+// provided MetricFamily. It also hashes the Metric labels and the MetricFamily
+// name. If the resulting hash is already in the provided metricHashes, an error
+// is returned. If not, it is added to metricHashes.
+func checkMetricConsistency(
+	metricFamily *dto.MetricFamily,
+	dtoMetric *dto.Metric,
+	metricHashes map[uint64]struct{},
+) error {
+	name := metricFamily.GetName()
+
+	// Type consistency with metric family.
+	if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil ||
+		metricFamily.GetType() == dto.MetricType_COUNTER && dtoMetric.Counter == nil ||
+		metricFamily.GetType() == dto.MetricType_SUMMARY && dtoMetric.Summary == nil ||
+		metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
+		metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
+		return fmt.Errorf(
+			"collected metric %q { %s} is not a %s",
+			name, dtoMetric, metricFamily.GetType(),
+		)
+	}
+
+	previousLabelName := ""
+	for _, labelPair := range dtoMetric.GetLabel() {
+		labelName := labelPair.GetName()
+		if labelName == previousLabelName {
+			return fmt.Errorf(
+				"collected metric %q { %s} has two or more labels with the same name: %s",
+				name, dtoMetric, labelName,
+			)
+		}
+		if !checkLabelName(labelName) {
+			return fmt.Errorf(
+				"collected metric %q { %s} has a label with an invalid name: %s",
+				name, dtoMetric, labelName,
+			)
+		}
+		if dtoMetric.Summary != nil && labelName == quantileLabel {
+			return fmt.Errorf(
+				"collected metric %q { %s} must not have an explicit %q label",
+				name, dtoMetric, quantileLabel,
+			)
+		}
+		if !utf8.ValidString(labelPair.GetValue()) {
+			return fmt.Errorf(
+				"collected metric %q { %s} has a label named %q whose value is not utf8: %#v",
+				name, dtoMetric, labelName, labelPair.GetValue())
+		}
+		previousLabelName = labelName
+	}
+
+	// Is the metric unique (i.e. no other metric with the same name and the same labels)?
+	h := hashNew()
+	h = hashAdd(h, name)
+	h = hashAddByte(h, separatorByte)
+	// Make sure label pairs are sorted. We depend on it for the consistency
+	// check.
+	if !sort.IsSorted(labelPairSorter(dtoMetric.Label)) {
+		// We cannot sort dtoMetric.Label in place as it is immutable by contract.
+		copiedLabels := make([]*dto.LabelPair, len(dtoMetric.Label))
+		copy(copiedLabels, dtoMetric.Label)
+		sort.Sort(labelPairSorter(copiedLabels))
+		dtoMetric.Label = copiedLabels
+	}
+	for _, lp := range dtoMetric.Label {
+		h = hashAdd(h, lp.GetName())
+		h = hashAddByte(h, separatorByte)
+		h = hashAdd(h, lp.GetValue())
+		h = hashAddByte(h, separatorByte)
+	}
+	if _, exists := metricHashes[h]; exists {
+		return fmt.Errorf(
+			"collected metric %q { %s} was collected before with the same name and label values",
+			name, dtoMetric,
+		)
+	}
+	metricHashes[h] = struct{}{}
+	return nil
+}
+
+func checkDescConsistency(
+	metricFamily *dto.MetricFamily,
+	dtoMetric *dto.Metric,
+	desc *Desc,
+) error {
+	// Desc help consistency with metric family help.
+	if metricFamily.GetHelp() != desc.help {
+		return fmt.Errorf(
+			"collected metric %s %s has help %q but should have %q",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetHelp(), desc.help,
+		)
+	}
+
+	// Is the desc consistent with the content of the metric?
+	lpsFromDesc := make([]*dto.LabelPair, len(desc.constLabelPairs), len(dtoMetric.Label))
+	copy(lpsFromDesc, desc.constLabelPairs)
+	for _, l := range desc.variableLabels {
+		lpsFromDesc = append(lpsFromDesc, &dto.LabelPair{
+			Name: proto.String(l),
+		})
+	}
+	if len(lpsFromDesc) != len(dtoMetric.Label) {
+		return fmt.Errorf(
+			"labels in collected metric %s %s are inconsistent with descriptor %s",
+			metricFamily.GetName(), dtoMetric, desc,
+		)
+	}
+	sort.Sort(labelPairSorter(lpsFromDesc))
+	for i, lpFromDesc := range lpsFromDesc {
+		lpFromMetric := dtoMetric.Label[i]
+		if lpFromDesc.GetName() != lpFromMetric.GetName() ||
+			lpFromDesc.Value != nil && lpFromDesc.GetValue() != lpFromMetric.GetValue() {
+			return fmt.Errorf(
+				"labels in collected metric %s %s are inconsistent with descriptor %s",
+				metricFamily.GetName(), dtoMetric, desc,
+			)
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/summary.go b/vendor/github.com/prometheus/client_golang/prometheus/summary.go
new file mode 100644
index 0000000000..2980614dff
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/summary.go
@@ -0,0 +1,626 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/beorn7/perks/quantile"
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// quantileLabel is used for the label that defines the quantile in a
+// summary.
+const quantileLabel = "quantile"
+
+// A Summary captures individual observations from an event or sample stream and
+// summarizes them in a manner similar to traditional summary statistics: 1. sum
+// of observations, 2. observation count, 3. rank estimations.
+//
+// A typical use-case is the observation of request latencies. By default, a
+// Summary provides the median, the 90th and the 99th percentile of the latency
+// as rank estimations. However, the default behavior will change in the
+// upcoming v0.10 of the library. There will be no rank estimations at all by
+// default. For a sane transition, it is recommended to set the desired rank
+// estimations explicitly.
+//
+// Note that the rank estimations cannot be aggregated in a meaningful way with
+// the Prometheus query language (i.e. you cannot average or add them). If you
+// need aggregatable quantiles (e.g. you want the 99th percentile latency of all
+// queries served across all instances of a service), consider the Histogram
+// metric type. See the Prometheus documentation for more details.
+//
+// To create Summary instances, use NewSummary.
+type Summary interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the summary.
+	Observe(float64)
+}
+
+// DefObjectives are the default Summary quantile values.
+//
+// Deprecated: DefObjectives will not be used as the default objectives in
+// v0.10 of the library. The default Summary will have no quantiles then.
+var (
+	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
+
+	errQuantileLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in summaries", quantileLabel,
+	)
+)
+
+// Default values for SummaryOpts.
+const (
+	// DefMaxAge is the default duration for which observations stay
+	// relevant.
+	DefMaxAge time.Duration = 10 * time.Minute
+	// DefAgeBuckets is the default number of buckets used to calculate the
+	// age of observations.
+	DefAgeBuckets = 5
+	// DefBufCap is the standard buffer size for collecting Summary observations.
+	DefBufCap = 500
+)
+
+// SummaryOpts bundles the options for creating a Summary metric. It is
+// mandatory to set Name to a non-empty string. While all other fields are
+// optional and can safely be left at their zero value, it is recommended to set
+// a help string and to explicitly set the Objectives field to the desired value
+// as the default value will change in the upcoming v0.10 of the library.
+type SummaryOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Summary (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Summary must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Summary.
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
+	// with the same fully-qualified name must have the same label names in
+	// their ConstLabels.
+	//
+	// Due to the way a Summary is represented in the Prometheus text format
+	// and how it is handled by the Prometheus server internally, “quantile”
+	// is an illegal label name. Construction of a Summary or SummaryVec
+	// will panic if this label name is used in ConstLabels.
+	//
+	// ConstLabels are only used rarely. In particular, do not use them to
+	// attach the same labels to all your metrics. Those use cases are
+	// better covered by target labels set by the scraping Prometheus
+	// server, or by one specific metric (e.g. a build_info or a
+	// machine_role metric). See also
+	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
+	ConstLabels Labels
+
+	// Objectives defines the quantile rank estimates with their respective
+	// absolute error. If Objectives[q] = e, then the value reported for q
+	// will be the φ-quantile value for some φ between q-e and q+e.  The
+	// default value is DefObjectives. It is used if Objectives is left at
+	// its zero value (i.e. nil). To create a Summary without Objectives,
+	// set it to an empty map (i.e. map[float64]float64{}).
+	//
+	// Deprecated: Note that the current value of DefObjectives is
+	// deprecated. It will be replaced by an empty map in v0.10 of the
+	// library. Please explicitly set Objectives to the desired value.
+	Objectives map[float64]float64
+
+	// MaxAge defines the duration for which an observation stays relevant
+	// for the summary. Must be positive. The default value is DefMaxAge.
+	MaxAge time.Duration
+
+	// AgeBuckets is the number of buckets used to exclude observations that
+	// are older than MaxAge from the summary. A higher number has a
+	// resource penalty, so only increase it if the higher resolution is
+	// really required. For very high observation rates, you might want to
+	// reduce the number of age buckets. With only one age bucket, you will
+	// effectively see a complete reset of the summary each time MaxAge has
+	// passed. The default value is DefAgeBuckets.
+	AgeBuckets uint32
+
+	// BufCap defines the default sample stream buffer size.  The default
+	// value of DefBufCap should suffice for most uses. If there is a need
+	// to increase the value, a multiple of 500 is recommended (because that
+	// is the internal buffer size of the underlying package
+	// "github.com/bmizerany/perks/quantile").
+	BufCap uint32
+}
+
+// Great fuck-up with the sliding-window decay algorithm... The Merge method of
+// perk/quantile is actually not working as advertised - and it might be
+// unfixable, as the underlying algorithm is apparently not capable of merging
+// summaries in the first place. To avoid using Merge, we are currently adding
+// observations to _each_ age bucket, i.e. the effort to add a sample is
+// essentially multiplied by the number of age buckets. When rotating age
+// buckets, we empty the previous head stream. On scrape time, we simply take
+// the quantiles from the head stream (no merging required). Result: More effort
+// on observation time, less effort on scrape time, which is exactly the
+// opposite of what we try to accomplish, but at least the results are correct.
+//
+// The quite elegant previous contraption to merge the age buckets efficiently
+// on scrape time (see code up commit 6b9530d72ea715f0ba612c0120e6e09fbf1d49d0)
+// can't be used anymore.
+
+// NewSummary creates a new Summary based on the provided SummaryOpts.
+func NewSummary(opts SummaryOpts) Summary {
+	return newSummary(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, labelValues))
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+
+	if opts.Objectives == nil {
+		opts.Objectives = DefObjectives
+	}
+
+	if opts.MaxAge < 0 {
+		panic(fmt.Errorf("illegal max age MaxAge=%v", opts.MaxAge))
+	}
+	if opts.MaxAge == 0 {
+		opts.MaxAge = DefMaxAge
+	}
+
+	if opts.AgeBuckets == 0 {
+		opts.AgeBuckets = DefAgeBuckets
+	}
+
+	if opts.BufCap == 0 {
+		opts.BufCap = DefBufCap
+	}
+
+	s := &summary{
+		desc: desc,
+
+		objectives:       opts.Objectives,
+		sortedObjectives: make([]float64, 0, len(opts.Objectives)),
+
+		labelPairs: makeLabelPairs(desc, labelValues),
+
+		hotBuf:         make([]float64, 0, opts.BufCap),
+		coldBuf:        make([]float64, 0, opts.BufCap),
+		streamDuration: opts.MaxAge / time.Duration(opts.AgeBuckets),
+	}
+	s.headStreamExpTime = time.Now().Add(s.streamDuration)
+	s.hotBufExpTime = s.headStreamExpTime
+
+	for i := uint32(0); i < opts.AgeBuckets; i++ {
+		s.streams = append(s.streams, s.newStream())
+	}
+	s.headStream = s.streams[0]
+
+	for qu := range s.objectives {
+		s.sortedObjectives = append(s.sortedObjectives, qu)
+	}
+	sort.Float64s(s.sortedObjectives)
+
+	s.init(s) // Init self-collection.
+	return s
+}
+
+type summary struct {
+	selfCollector
+
+	bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime.
+	mtx    sync.Mutex // Protects every other moving part.
+	// Lock bufMtx before mtx if both are needed.
+
+	desc *Desc
+
+	objectives       map[float64]float64
+	sortedObjectives []float64
+
+	labelPairs []*dto.LabelPair
+
+	sum float64
+	cnt uint64
+
+	hotBuf, coldBuf []float64
+
+	streams                          []*quantile.Stream
+	streamDuration                   time.Duration
+	headStream                       *quantile.Stream
+	headStreamIdx                    int
+	headStreamExpTime, hotBufExpTime time.Time
+}
+
+func (s *summary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *summary) Observe(v float64) {
+	s.bufMtx.Lock()
+	defer s.bufMtx.Unlock()
+
+	now := time.Now()
+	if now.After(s.hotBufExpTime) {
+		s.asyncFlush(now)
+	}
+	s.hotBuf = append(s.hotBuf, v)
+	if len(s.hotBuf) == cap(s.hotBuf) {
+		s.asyncFlush(now)
+	}
+}
+
+func (s *summary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.objectives))
+
+	s.bufMtx.Lock()
+	s.mtx.Lock()
+	// Swap bufs even if hotBuf is empty to set new hotBufExpTime.
+	s.swapBufs(time.Now())
+	s.bufMtx.Unlock()
+
+	s.flushColdBuf()
+	sum.SampleCount = proto.Uint64(s.cnt)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for _, rank := range s.sortedObjectives {
+		var q float64
+		if s.headStream.Count() == 0 {
+			q = math.NaN()
+		} else {
+			q = s.headStream.Query(rank)
+		}
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	s.mtx.Unlock()
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+	return nil
+}
+
+func (s *summary) newStream() *quantile.Stream {
+	return quantile.NewTargeted(s.objectives)
+}
+
+// asyncFlush needs bufMtx locked.
+func (s *summary) asyncFlush(now time.Time) {
+	s.mtx.Lock()
+	s.swapBufs(now)
+
+	// Unblock the original goroutine that was responsible for the mutation
+	// that triggered the compaction.  But hold onto the global non-buffer
+	// state mutex until the operation finishes.
+	go func() {
+		s.flushColdBuf()
+		s.mtx.Unlock()
+	}()
+}
+
+// rotateStreams needs mtx AND bufMtx locked.
+func (s *summary) maybeRotateStreams() {
+	for !s.hotBufExpTime.Equal(s.headStreamExpTime) {
+		s.headStream.Reset()
+		s.headStreamIdx++
+		if s.headStreamIdx >= len(s.streams) {
+			s.headStreamIdx = 0
+		}
+		s.headStream = s.streams[s.headStreamIdx]
+		s.headStreamExpTime = s.headStreamExpTime.Add(s.streamDuration)
+	}
+}
+
+// flushColdBuf needs mtx locked.
+func (s *summary) flushColdBuf() {
+	for _, v := range s.coldBuf {
+		for _, stream := range s.streams {
+			stream.Insert(v)
+		}
+		s.cnt++
+		s.sum += v
+	}
+	s.coldBuf = s.coldBuf[0:0]
+	s.maybeRotateStreams()
+}
+
+// swapBufs needs mtx AND bufMtx locked, coldBuf must be empty.
+func (s *summary) swapBufs(now time.Time) {
+	if len(s.coldBuf) != 0 {
+		panic("coldBuf is not empty")
+	}
+	s.hotBuf, s.coldBuf = s.coldBuf, s.hotBuf
+	// hotBuf is now empty and gets new expiration set.
+	for now.After(s.hotBufExpTime) {
+		s.hotBufExpTime = s.hotBufExpTime.Add(s.streamDuration)
+	}
+}
+
+type quantSort []*dto.Quantile
+
+func (s quantSort) Len() int {
+	return len(s)
+}
+
+func (s quantSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s quantSort) Less(i, j int) bool {
+	return s[i].GetQuantile() < s[j].GetQuantile()
+}
+
+// SummaryVec is a Collector that bundles a set of Summaries that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewSummaryVec.
+type SummaryVec struct {
+	*metricVec
+}
+
+// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
+// partitioned by the given label names.
+//
+// Due to the way a Summary is represented in the Prometheus text format and how
+// it is handled by the Prometheus server internally, “quantile” is an illegal
+// label name. NewSummaryVec will panic if this label name is used.
+func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
+	for _, ln := range labelNames {
+		if ln == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &SummaryVec{
+		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newSummary(desc, opts, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues returns the Summary for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Summary is created.
+//
+// It is possible to call this method without using the returned Summary to only
+// create the new Summary but leave it at its starting value, a Summary without
+// any observations.
+//
+// Keeping the Summary for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Summary from the SummaryVec. In that case,
+// the Summary will still exist, but it will not be exported anymore, even if a
+// Summary with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
+	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Observer), err
+	}
+	return nil, err
+}
+
+// GetMetricWith returns the Summary for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Summary is created. Implications of
+// creating a Summary without using it and keeping the Summary for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
+	metric, err := v.metricVec.getMetricWith(labels)
+	if metric != nil {
+		return metric.(Observer), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (v *SummaryVec) WithLabelValues(lvs ...string) Observer {
+	s, err := v.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return s
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (v *SummaryVec) With(labels Labels) Observer {
+	s, err := v.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return s
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the SummaryVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *SummaryVec) CurryWith(labels Labels) (ObserverVec, error) {
+	vec, err := v.curryWith(labels)
+	if vec != nil {
+		return &SummaryVec{vec}, err
+	}
+	return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *SummaryVec) MustCurryWith(labels Labels) ObserverVec {
+	vec, err := v.CurryWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return vec
+}
+
+type constSummary struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	quantiles  map[float64]float64
+	labelPairs []*dto.LabelPair
+}
+
+func (s *constSummary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *constSummary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.quantiles))
+
+	sum.SampleCount = proto.Uint64(s.count)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for rank, q := range s.quantiles {
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+
+	return nil
+}
+
+// NewConstSummary returns a metric representing a Prometheus summary with fixed
+// values for the count, sum, and quantiles. As those parameters cannot be
+// changed, the returned value does not implement the Summary interface (but
+// only the Metric interface). Users of this package will not have much use for
+// it in regular operations. However, when implementing custom Collectors, it is
+// useful as a throw-away metric that is generated on the fly to send it to
+// Prometheus in the Collect method.
+//
+// quantiles maps ranks to quantile values. For example, a median latency of
+// 0.23s and a 99th percentile latency of 0.56s would be expressed as:
+//     map[float64]float64{0.5: 0.23, 0.99: 0.56}
+//
+// NewConstSummary returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc or if Desc is invalid.
+func NewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
+		return nil, err
+	}
+	return &constSummary{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		quantiles:  quantiles,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstSummary is a version of NewConstSummary that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstSummary(desc, count, sum, quantiles, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/timer.go b/vendor/github.com/prometheus/client_golang/prometheus/timer.go
new file mode 100644
index 0000000000..8d5f105233
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/timer.go
@@ -0,0 +1,54 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "time"
+
+// Timer is a helper type to time functions. Use NewTimer to create new
+// instances.
+type Timer struct {
+	begin    time.Time
+	observer Observer
+}
+
+// NewTimer creates a new Timer. The provided Observer is used to observe a
+// duration in seconds. Timer is usually used to time a function call in the
+// following way:
+//    func TimeMe() {
+//        timer := NewTimer(myHistogram)
+//        defer timer.ObserveDuration()
+//        // Do actual work.
+//    }
+func NewTimer(o Observer) *Timer {
+	return &Timer{
+		begin:    time.Now(),
+		observer: o,
+	}
+}
+
+// ObserveDuration records the duration passed since the Timer was created with
+// NewTimer. It calls the Observe method of the Observer provided during
+// construction with the duration in seconds as an argument. The observed
+// duration is also returned. ObserveDuration is usually called with a defer
+// statement.
+//
+// Note that this method is only guaranteed to never observe negative durations
+// if used with Go1.9+.
+func (t *Timer) ObserveDuration() time.Duration {
+	d := time.Since(t.begin)
+	if t.observer != nil {
+		t.observer.Observe(d.Seconds())
+	}
+	return d
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/untyped.go b/vendor/github.com/prometheus/client_golang/prometheus/untyped.go
new file mode 100644
index 0000000000..0f9ce63f40
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/untyped.go
@@ -0,0 +1,42 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// UntypedOpts is an alias for Opts. See there for doc comments.
+type UntypedOpts Opts
+
+// UntypedFunc works like GaugeFunc but the collected metric is of type
+// "Untyped". UntypedFunc is useful to mirror an external metric of unknown
+// type.
+//
+// To create UntypedFunc instances, use NewUntypedFunc.
+type UntypedFunc interface {
+	Metric
+	Collector
+}
+
+// NewUntypedFunc creates a new UntypedFunc based on the provided
+// UntypedOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where an UntypedFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func NewUntypedFunc(opts UntypedOpts, function func() float64) UntypedFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, function)
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/value.go b/vendor/github.com/prometheus/client_golang/prometheus/value.go
new file mode 100644
index 0000000000..eb248f1087
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/value.go
@@ -0,0 +1,162 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// ValueType is an enumeration of metric types that represent a simple value.
+type ValueType int
+
+// Possible values for the ValueType enum.
+const (
+	_ ValueType = iota
+	CounterValue
+	GaugeValue
+	UntypedValue
+)
+
+// valueFunc is a generic metric for simple values retrieved on collect time
+// from a function. It implements Metric and Collector. Its effective type is
+// determined by ValueType. This is a low-level building block used by the
+// library to back the implementations of CounterFunc, GaugeFunc, and
+// UntypedFunc.
+type valueFunc struct {
+	selfCollector
+
+	desc       *Desc
+	valType    ValueType
+	function   func() float64
+	labelPairs []*dto.LabelPair
+}
+
+// newValueFunc returns a newly allocated valueFunc with the given Desc and
+// ValueType. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a valueFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc {
+	result := &valueFunc{
+		desc:       desc,
+		valType:    valueType,
+		function:   function,
+		labelPairs: makeLabelPairs(desc, nil),
+	}
+	result.init(result)
+	return result
+}
+
+func (v *valueFunc) Desc() *Desc {
+	return v.desc
+}
+
+func (v *valueFunc) Write(out *dto.Metric) error {
+	return populateMetric(v.valType, v.function(), v.labelPairs, out)
+}
+
+// NewConstMetric returns a metric with one fixed value that cannot be
+// changed. Users of this package will not have much use for it in regular
+// operations. However, when implementing custom Collectors, it is useful as a
+// throw-away metric that is generated on the fly to send it to Prometheus in
+// the Collect method. NewConstMetric returns an error if the length of
+// labelValues is not consistent with the variable labels in Desc or if Desc is
+// invalid.
+func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
+	if desc.err != nil {
+		return nil, desc.err
+	}
+	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
+		return nil, err
+	}
+	return &constMetric{
+		desc:       desc,
+		valType:    valueType,
+		val:        value,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstMetric is a version of NewConstMetric that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric {
+	m, err := NewConstMetric(desc, valueType, value, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type constMetric struct {
+	desc       *Desc
+	valType    ValueType
+	val        float64
+	labelPairs []*dto.LabelPair
+}
+
+func (m *constMetric) Desc() *Desc {
+	return m.desc
+}
+
+func (m *constMetric) Write(out *dto.Metric) error {
+	return populateMetric(m.valType, m.val, m.labelPairs, out)
+}
+
+func populateMetric(
+	t ValueType,
+	v float64,
+	labelPairs []*dto.LabelPair,
+	m *dto.Metric,
+) error {
+	m.Label = labelPairs
+	switch t {
+	case CounterValue:
+		m.Counter = &dto.Counter{Value: proto.Float64(v)}
+	case GaugeValue:
+		m.Gauge = &dto.Gauge{Value: proto.Float64(v)}
+	case UntypedValue:
+		m.Untyped = &dto.Untyped{Value: proto.Float64(v)}
+	default:
+		return fmt.Errorf("encountered unknown type %v", t)
+	}
+	return nil
+}
+
+func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
+	totalLen := len(desc.variableLabels) + len(desc.constLabelPairs)
+	if totalLen == 0 {
+		// Super fast path.
+		return nil
+	}
+	if len(desc.variableLabels) == 0 {
+		// Moderately fast path.
+		return desc.constLabelPairs
+	}
+	labelPairs := make([]*dto.LabelPair, 0, totalLen)
+	for i, n := range desc.variableLabels {
+		labelPairs = append(labelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(labelValues[i]),
+		})
+	}
+	labelPairs = append(labelPairs, desc.constLabelPairs...)
+	sort.Sort(labelPairSorter(labelPairs))
+	return labelPairs
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go
new file mode 100644
index 0000000000..14ed9e856d
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/vec.go
@@ -0,0 +1,472 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/prometheus/common/model"
+)
+
+// metricVec is a Collector to bundle metrics of the same name that differ in
+// their label values. metricVec is not used directly (and therefore
+// unexported). It is used as a building block for implementations of vectors of
+// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec.
+// It also handles label currying. It uses basicMetricVec internally.
+type metricVec struct {
+	*metricMap
+
+	curry []curriedLabelValue
+
+	// hashAdd and hashAddByte can be replaced for testing collision handling.
+	hashAdd     func(h uint64, s string) uint64
+	hashAddByte func(h uint64, b byte) uint64
+}
+
+// newMetricVec returns an initialized metricVec.
+func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec {
+	return &metricVec{
+		metricMap: &metricMap{
+			metrics:   map[uint64][]metricWithLabelValues{},
+			desc:      desc,
+			newMetric: newMetric,
+		},
+		hashAdd:     hashAdd,
+		hashAddByte: hashAddByte,
+	}
+}
+
+// DeleteLabelValues removes the metric where the variable labels are the same
+// as those passed in as labels (same order as the VariableLabels in Desc). It
+// returns true if a metric was deleted.
+//
+// It is not an error if the number of label values is not the same as the
+// number of VariableLabels in Desc. However, such inconsistent label count can
+// never match an actual metric, so the method will always return false in that
+// case.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider Delete(Labels) as an
+// alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the CounterVec example.
+func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return false
+	}
+
+	return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry)
+}
+
+// Delete deletes the metric where the variable labels are the same as those
+// passed in as labels. It returns true if a metric was deleted.
+//
+// It is not an error if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc. However, such inconsistent Labels
+// can never match an actual metric, so the method will always return false in
+// that case.
+//
+// This method is used for the same purpose as DeleteLabelValues(...string). See
+// there for pros and cons of the two methods.
+func (m *metricVec) Delete(labels Labels) bool {
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return false
+	}
+
+	return m.metricMap.deleteByHashWithLabels(h, labels, m.curry)
+}
+
+func (m *metricVec) curryWith(labels Labels) (*metricVec, error) {
+	var (
+		newCurry []curriedLabelValue
+		oldCurry = m.curry
+		iCurry   int
+	)
+	for i, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if iCurry < len(oldCurry) && oldCurry[iCurry].index == i {
+			if ok {
+				return nil, fmt.Errorf("label name %q is already curried", label)
+			}
+			newCurry = append(newCurry, oldCurry[iCurry])
+			iCurry++
+		} else {
+			if !ok {
+				continue // Label stays uncurried.
+			}
+			newCurry = append(newCurry, curriedLabelValue{i, val})
+		}
+	}
+	if l := len(oldCurry) + len(labels) - len(newCurry); l > 0 {
+		return nil, fmt.Errorf("%d unknown label(s) found during currying", l)
+	}
+
+	return &metricVec{
+		metricMap:   m.metricMap,
+		curry:       newCurry,
+		hashAdd:     m.hashAdd,
+		hashAddByte: m.hashAddByte,
+	}, nil
+}
+
+func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.metricMap.getOrCreateMetricWithLabelValues(h, lvs, m.curry), nil
+}
+
+func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.metricMap.getOrCreateMetricWithLabels(h, labels, m.curry), nil
+}
+
+func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
+	if err := validateLabelValues(vals, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+		return 0, err
+	}
+
+	var (
+		h             = hashNew()
+		curry         = m.curry
+		iVals, iCurry int
+	)
+	for i := 0; i < len(m.desc.variableLabels); i++ {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			h = m.hashAdd(h, curry[iCurry].value)
+			iCurry++
+		} else {
+			h = m.hashAdd(h, vals[iVals])
+			iVals++
+		}
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
+func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
+	if err := validateValuesInLabels(labels, len(m.desc.variableLabels)-len(m.curry)); err != nil {
+		return 0, err
+	}
+
+	var (
+		h      = hashNew()
+		curry  = m.curry
+		iCurry int
+	)
+	for i, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if ok {
+				return 0, fmt.Errorf("label name %q is already curried", label)
+			}
+			h = m.hashAdd(h, curry[iCurry].value)
+			iCurry++
+		} else {
+			if !ok {
+				return 0, fmt.Errorf("label name %q missing in label map", label)
+			}
+			h = m.hashAdd(h, val)
+		}
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
+// metricWithLabelValues provides the metric and its label values for
+// disambiguation on hash collision.
+type metricWithLabelValues struct {
+	values []string
+	metric Metric
+}
+
+// curriedLabelValue sets the curried value for a label at the given index.
+type curriedLabelValue struct {
+	index int
+	value string
+}
+
+// metricMap is a helper for metricVec and shared between differently curried
+// metricVecs.
+type metricMap struct {
+	mtx       sync.RWMutex // Protects metrics.
+	metrics   map[uint64][]metricWithLabelValues
+	desc      *Desc
+	newMetric func(labelValues ...string) Metric
+}
+
+// Describe implements Collector. It will send exactly one Desc to the provided
+// channel.
+func (m *metricMap) Describe(ch chan<- *Desc) {
+	ch <- m.desc
+}
+
+// Collect implements Collector.
+func (m *metricMap) Collect(ch chan<- Metric) {
+	m.mtx.RLock()
+	defer m.mtx.RUnlock()
+
+	for _, metrics := range m.metrics {
+		for _, metric := range metrics {
+			ch <- metric.metric
+		}
+	}
+}
+
+// Reset deletes all metrics in this vector.
+func (m *metricMap) Reset() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	for h := range m.metrics {
+		delete(m.metrics, h)
+	}
+}
+
+// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
+// there are multiple matches in the bucket, use lvs to select a metric and
+// remove only that metric.
+func (m *metricMap) deleteByHashWithLabelValues(
+	h uint64, lvs []string, curry []curriedLabelValue,
+) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	metrics, ok := m.metrics[h]
+	if !ok {
+		return false
+	}
+
+	i := findMetricWithLabelValues(metrics, lvs, curry)
+	if i >= len(metrics) {
+		return false
+	}
+
+	if len(metrics) > 1 {
+		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
+	} else {
+		delete(m.metrics, h)
+	}
+	return true
+}
+
+// deleteByHashWithLabels removes the metric from the hash bucket h. If there
+// are multiple matches in the bucket, use lvs to select a metric and remove
+// only that metric.
+func (m *metricMap) deleteByHashWithLabels(
+	h uint64, labels Labels, curry []curriedLabelValue,
+) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	metrics, ok := m.metrics[h]
+	if !ok {
+		return false
+	}
+	i := findMetricWithLabels(m.desc, metrics, labels, curry)
+	if i >= len(metrics) {
+		return false
+	}
+
+	if len(metrics) > 1 {
+		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
+	} else {
+		delete(m.metrics, h)
+	}
+	return true
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *metricMap) getOrCreateMetricWithLabelValues(
+	hash uint64, lvs []string, curry []curriedLabelValue,
+) Metric {
+	m.mtx.RLock()
+	metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry)
+	m.mtx.RUnlock()
+	if ok {
+		return metric
+	}
+
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+	metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry)
+	if !ok {
+		inlinedLVs := inlineLabelValues(lvs, curry)
+		metric = m.newMetric(inlinedLVs...)
+		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric})
+	}
+	return metric
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *metricMap) getOrCreateMetricWithLabels(
+	hash uint64, labels Labels, curry []curriedLabelValue,
+) Metric {
+	m.mtx.RLock()
+	metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry)
+	m.mtx.RUnlock()
+	if ok {
+		return metric
+	}
+
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+	metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry)
+	if !ok {
+		lvs := extractLabelValues(m.desc, labels, curry)
+		metric = m.newMetric(lvs...)
+		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric})
+	}
+	return metric
+}
+
+// getMetricWithHashAndLabelValues gets a metric while handling possible
+// collisions in the hash space. Must be called while holding the read mutex.
+func (m *metricMap) getMetricWithHashAndLabelValues(
+	h uint64, lvs []string, curry []curriedLabelValue,
+) (Metric, bool) {
+	metrics, ok := m.metrics[h]
+	if ok {
+		if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) {
+			return metrics[i].metric, true
+		}
+	}
+	return nil, false
+}
+
+// getMetricWithHashAndLabels gets a metric while handling possible collisions in
+// the hash space. Must be called while holding read mutex.
+func (m *metricMap) getMetricWithHashAndLabels(
+	h uint64, labels Labels, curry []curriedLabelValue,
+) (Metric, bool) {
+	metrics, ok := m.metrics[h]
+	if ok {
+		if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) {
+			return metrics[i].metric, true
+		}
+	}
+	return nil, false
+}
+
+// findMetricWithLabelValues returns the index of the matching metric or
+// len(metrics) if not found.
+func findMetricWithLabelValues(
+	metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue,
+) int {
+	for i, metric := range metrics {
+		if matchLabelValues(metric.values, lvs, curry) {
+			return i
+		}
+	}
+	return len(metrics)
+}
+
+// findMetricWithLabels returns the index of the matching metric or len(metrics)
+// if not found.
+func findMetricWithLabels(
+	desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue,
+) int {
+	for i, metric := range metrics {
+		if matchLabels(desc, metric.values, labels, curry) {
+			return i
+		}
+	}
+	return len(metrics)
+}
+
+func matchLabelValues(values []string, lvs []string, curry []curriedLabelValue) bool {
+	if len(values) != len(lvs)+len(curry) {
+		return false
+	}
+	var iLVs, iCurry int
+	for i, v := range values {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if v != curry[iCurry].value {
+				return false
+			}
+			iCurry++
+			continue
+		}
+		if v != lvs[iLVs] {
+			return false
+		}
+		iLVs++
+	}
+	return true
+}
+
+func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool {
+	if len(values) != len(labels)+len(curry) {
+		return false
+	}
+	iCurry := 0
+	for i, k := range desc.variableLabels {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			if values[i] != curry[iCurry].value {
+				return false
+			}
+			iCurry++
+			continue
+		}
+		if values[i] != labels[k] {
+			return false
+		}
+	}
+	return true
+}
+
+func extractLabelValues(desc *Desc, labels Labels, curry []curriedLabelValue) []string {
+	labelValues := make([]string, len(labels)+len(curry))
+	iCurry := 0
+	for i, k := range desc.variableLabels {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			labelValues[i] = curry[iCurry].value
+			iCurry++
+			continue
+		}
+		labelValues[i] = labels[k]
+	}
+	return labelValues
+}
+
+func inlineLabelValues(lvs []string, curry []curriedLabelValue) []string {
+	labelValues := make([]string, len(lvs)+len(curry))
+	var iCurry, iLVs int
+	for i := range labelValues {
+		if iCurry < len(curry) && curry[iCurry].index == i {
+			labelValues[i] = curry[iCurry].value
+			iCurry++
+			continue
+		}
+		labelValues[i] = lvs[iLVs]
+		iLVs++
+	}
+	return labelValues
+}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/wrap.go b/vendor/github.com/prometheus/client_golang/prometheus/wrap.go
new file mode 100644
index 0000000000..49159bf3eb
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/wrap.go
@@ -0,0 +1,179 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// WrapRegistererWith returns a Registerer wrapping the provided
+// Registerer. Collectors registered with the returned Registerer will be
+// registered with the wrapped Registerer in a modified way. The modified
+// Collector adds the provided Labels to all Metrics it collects (as
+// ConstLabels). The Metrics collected by the unmodified Collector must not
+// duplicate any of those labels.
+//
+// WrapRegistererWith provides a way to add fixed labels to a subset of
+// Collectors. It should not be used to add fixed labels to all metrics exposed.
+//
+// The Collector example demonstrates a use of WrapRegistererWith.
+func WrapRegistererWith(labels Labels, reg Registerer) Registerer {
+	return &wrappingRegisterer{
+		wrappedRegisterer: reg,
+		labels:            labels,
+	}
+}
+
+// WrapRegistererWithPrefix returns a Registerer wrapping the provided
+// Registerer. Collectors registered with the returned Registerer will be
+// registered with the wrapped Registerer in a modified way. The modified
+// Collector adds the provided prefix to the name of all Metrics it collects.
+//
+// WrapRegistererWithPrefix is useful to have one place to prefix all metrics of
+// a sub-system. To make this work, register metrics of the sub-system with the
+// wrapping Registerer returned by WrapRegistererWithPrefix. It is rarely useful
+// to use the same prefix for all metrics exposed. In particular, do not prefix
+// metric names that are standardized across applications, as that would break
+// horizontal monitoring, for example the metrics provided by the Go collector
+// (see NewGoCollector) and the process collector (see NewProcessCollector). (In
+// fact, those metrics are already prefixed with “go_” or “process_”,
+// respectively.)
+func WrapRegistererWithPrefix(prefix string, reg Registerer) Registerer {
+	return &wrappingRegisterer{
+		wrappedRegisterer: reg,
+		prefix:            prefix,
+	}
+}
+
+type wrappingRegisterer struct {
+	wrappedRegisterer Registerer
+	prefix            string
+	labels            Labels
+}
+
+func (r *wrappingRegisterer) Register(c Collector) error {
+	return r.wrappedRegisterer.Register(&wrappingCollector{
+		wrappedCollector: c,
+		prefix:           r.prefix,
+		labels:           r.labels,
+	})
+}
+
+func (r *wrappingRegisterer) MustRegister(cs ...Collector) {
+	for _, c := range cs {
+		if err := r.Register(c); err != nil {
+			panic(err)
+		}
+	}
+}
+
+func (r *wrappingRegisterer) Unregister(c Collector) bool {
+	return r.wrappedRegisterer.Unregister(&wrappingCollector{
+		wrappedCollector: c,
+		prefix:           r.prefix,
+		labels:           r.labels,
+	})
+}
+
+type wrappingCollector struct {
+	wrappedCollector Collector
+	prefix           string
+	labels           Labels
+}
+
+func (c *wrappingCollector) Collect(ch chan<- Metric) {
+	wrappedCh := make(chan Metric)
+	go func() {
+		c.wrappedCollector.Collect(wrappedCh)
+		close(wrappedCh)
+	}()
+	for m := range wrappedCh {
+		ch <- &wrappingMetric{
+			wrappedMetric: m,
+			prefix:        c.prefix,
+			labels:        c.labels,
+		}
+	}
+}
+
+func (c *wrappingCollector) Describe(ch chan<- *Desc) {
+	wrappedCh := make(chan *Desc)
+	go func() {
+		c.wrappedCollector.Describe(wrappedCh)
+		close(wrappedCh)
+	}()
+	for desc := range wrappedCh {
+		ch <- wrapDesc(desc, c.prefix, c.labels)
+	}
+}
+
+type wrappingMetric struct {
+	wrappedMetric Metric
+	prefix        string
+	labels        Labels
+}
+
+func (m *wrappingMetric) Desc() *Desc {
+	return wrapDesc(m.wrappedMetric.Desc(), m.prefix, m.labels)
+}
+
+func (m *wrappingMetric) Write(out *dto.Metric) error {
+	if err := m.wrappedMetric.Write(out); err != nil {
+		return err
+	}
+	if len(m.labels) == 0 {
+		// No wrapping labels.
+		return nil
+	}
+	for ln, lv := range m.labels {
+		out.Label = append(out.Label, &dto.LabelPair{
+			Name:  proto.String(ln),
+			Value: proto.String(lv),
+		})
+	}
+	sort.Sort(labelPairSorter(out.Label))
+	return nil
+}
+
+func wrapDesc(desc *Desc, prefix string, labels Labels) *Desc {
+	constLabels := Labels{}
+	for _, lp := range desc.constLabelPairs {
+		constLabels[*lp.Name] = *lp.Value
+	}
+	for ln, lv := range labels {
+		if _, alreadyUsed := constLabels[ln]; alreadyUsed {
+			return &Desc{
+				fqName:          desc.fqName,
+				help:            desc.help,
+				variableLabels:  desc.variableLabels,
+				constLabelPairs: desc.constLabelPairs,
+				err:             fmt.Errorf("attempted wrapping with already existing label name %q", ln),
+			}
+		}
+		constLabels[ln] = lv
+	}
+	// NewDesc will do remaining validations.
+	newDesc := NewDesc(prefix+desc.fqName, desc.help, desc.variableLabels, constLabels)
+	// Propagate errors if there was any. This will override any errer
+	// created by NewDesc above, i.e. earlier errors get precedence.
+	if desc.err != nil {
+		newDesc.err = desc.err
+	}
+	return newDesc
+}
diff --git a/vendor/github.com/prometheus/client_model/LICENSE b/vendor/github.com/prometheus/client_model/LICENSE
new file mode 100644
index 0000000000..261eeb9e9f
--- /dev/null
+++ b/vendor/github.com/prometheus/client_model/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/prometheus/client_model/NOTICE b/vendor/github.com/prometheus/client_model/NOTICE
new file mode 100644
index 0000000000..20110e410e
--- /dev/null
+++ b/vendor/github.com/prometheus/client_model/NOTICE
@@ -0,0 +1,5 @@
+Data model artifacts for Prometheus.
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
diff --git a/vendor/github.com/prometheus/client_model/go/metrics.pb.go b/vendor/github.com/prometheus/client_model/go/metrics.pb.go
new file mode 100644
index 0000000000..9805432c2a
--- /dev/null
+++ b/vendor/github.com/prometheus/client_model/go/metrics.pb.go
@@ -0,0 +1,629 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: metrics.proto
+
+package io_prometheus_client // import "github.com/prometheus/client_model/go"
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+type MetricType int32
+
+const (
+	MetricType_COUNTER   MetricType = 0
+	MetricType_GAUGE     MetricType = 1
+	MetricType_SUMMARY   MetricType = 2
+	MetricType_UNTYPED   MetricType = 3
+	MetricType_HISTOGRAM MetricType = 4
+)
+
+var MetricType_name = map[int32]string{
+	0: "COUNTER",
+	1: "GAUGE",
+	2: "SUMMARY",
+	3: "UNTYPED",
+	4: "HISTOGRAM",
+}
+var MetricType_value = map[string]int32{
+	"COUNTER":   0,
+	"GAUGE":     1,
+	"SUMMARY":   2,
+	"UNTYPED":   3,
+	"HISTOGRAM": 4,
+}
+
+func (x MetricType) Enum() *MetricType {
+	p := new(MetricType)
+	*p = x
+	return p
+}
+func (x MetricType) String() string {
+	return proto.EnumName(MetricType_name, int32(x))
+}
+func (x *MetricType) UnmarshalJSON(data []byte) error {
+	value, err := proto.UnmarshalJSONEnum(MetricType_value, data, "MetricType")
+	if err != nil {
+		return err
+	}
+	*x = MetricType(value)
+	return nil
+}
+func (MetricType) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+}
+
+type LabelPair struct {
+	Name                 *string  `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Value                *string  `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *LabelPair) Reset()         { *m = LabelPair{} }
+func (m *LabelPair) String() string { return proto.CompactTextString(m) }
+func (*LabelPair) ProtoMessage()    {}
+func (*LabelPair) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{0}
+}
+func (m *LabelPair) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_LabelPair.Unmarshal(m, b)
+}
+func (m *LabelPair) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_LabelPair.Marshal(b, m, deterministic)
+}
+func (dst *LabelPair) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_LabelPair.Merge(dst, src)
+}
+func (m *LabelPair) XXX_Size() int {
+	return xxx_messageInfo_LabelPair.Size(m)
+}
+func (m *LabelPair) XXX_DiscardUnknown() {
+	xxx_messageInfo_LabelPair.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_LabelPair proto.InternalMessageInfo
+
+func (m *LabelPair) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *LabelPair) GetValue() string {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return ""
+}
+
+type Gauge struct {
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Gauge) Reset()         { *m = Gauge{} }
+func (m *Gauge) String() string { return proto.CompactTextString(m) }
+func (*Gauge) ProtoMessage()    {}
+func (*Gauge) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{1}
+}
+func (m *Gauge) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Gauge.Unmarshal(m, b)
+}
+func (m *Gauge) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Gauge.Marshal(b, m, deterministic)
+}
+func (dst *Gauge) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Gauge.Merge(dst, src)
+}
+func (m *Gauge) XXX_Size() int {
+	return xxx_messageInfo_Gauge.Size(m)
+}
+func (m *Gauge) XXX_DiscardUnknown() {
+	xxx_messageInfo_Gauge.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Gauge proto.InternalMessageInfo
+
+func (m *Gauge) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Counter struct {
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Counter) Reset()         { *m = Counter{} }
+func (m *Counter) String() string { return proto.CompactTextString(m) }
+func (*Counter) ProtoMessage()    {}
+func (*Counter) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{2}
+}
+func (m *Counter) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Counter.Unmarshal(m, b)
+}
+func (m *Counter) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Counter.Marshal(b, m, deterministic)
+}
+func (dst *Counter) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Counter.Merge(dst, src)
+}
+func (m *Counter) XXX_Size() int {
+	return xxx_messageInfo_Counter.Size(m)
+}
+func (m *Counter) XXX_DiscardUnknown() {
+	xxx_messageInfo_Counter.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Counter proto.InternalMessageInfo
+
+func (m *Counter) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Quantile struct {
+	Quantile             *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
+	Value                *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Quantile) Reset()         { *m = Quantile{} }
+func (m *Quantile) String() string { return proto.CompactTextString(m) }
+func (*Quantile) ProtoMessage()    {}
+func (*Quantile) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{3}
+}
+func (m *Quantile) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Quantile.Unmarshal(m, b)
+}
+func (m *Quantile) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Quantile.Marshal(b, m, deterministic)
+}
+func (dst *Quantile) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Quantile.Merge(dst, src)
+}
+func (m *Quantile) XXX_Size() int {
+	return xxx_messageInfo_Quantile.Size(m)
+}
+func (m *Quantile) XXX_DiscardUnknown() {
+	xxx_messageInfo_Quantile.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Quantile proto.InternalMessageInfo
+
+func (m *Quantile) GetQuantile() float64 {
+	if m != nil && m.Quantile != nil {
+		return *m.Quantile
+	}
+	return 0
+}
+
+func (m *Quantile) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Summary struct {
+	SampleCount          *uint64     `protobuf:"varint,1,opt,name=sample_count,json=sampleCount" json:"sample_count,omitempty"`
+	SampleSum            *float64    `protobuf:"fixed64,2,opt,name=sample_sum,json=sampleSum" json:"sample_sum,omitempty"`
+	Quantile             []*Quantile `protobuf:"bytes,3,rep,name=quantile" json:"quantile,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}    `json:"-"`
+	XXX_unrecognized     []byte      `json:"-"`
+	XXX_sizecache        int32       `json:"-"`
+}
+
+func (m *Summary) Reset()         { *m = Summary{} }
+func (m *Summary) String() string { return proto.CompactTextString(m) }
+func (*Summary) ProtoMessage()    {}
+func (*Summary) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{4}
+}
+func (m *Summary) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Summary.Unmarshal(m, b)
+}
+func (m *Summary) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Summary.Marshal(b, m, deterministic)
+}
+func (dst *Summary) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Summary.Merge(dst, src)
+}
+func (m *Summary) XXX_Size() int {
+	return xxx_messageInfo_Summary.Size(m)
+}
+func (m *Summary) XXX_DiscardUnknown() {
+	xxx_messageInfo_Summary.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Summary proto.InternalMessageInfo
+
+func (m *Summary) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Summary) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Summary) GetQuantile() []*Quantile {
+	if m != nil {
+		return m.Quantile
+	}
+	return nil
+}
+
+type Untyped struct {
+	Value                *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Untyped) Reset()         { *m = Untyped{} }
+func (m *Untyped) String() string { return proto.CompactTextString(m) }
+func (*Untyped) ProtoMessage()    {}
+func (*Untyped) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{5}
+}
+func (m *Untyped) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Untyped.Unmarshal(m, b)
+}
+func (m *Untyped) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Untyped.Marshal(b, m, deterministic)
+}
+func (dst *Untyped) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Untyped.Merge(dst, src)
+}
+func (m *Untyped) XXX_Size() int {
+	return xxx_messageInfo_Untyped.Size(m)
+}
+func (m *Untyped) XXX_DiscardUnknown() {
+	xxx_messageInfo_Untyped.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Untyped proto.InternalMessageInfo
+
+func (m *Untyped) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Histogram struct {
+	SampleCount          *uint64   `protobuf:"varint,1,opt,name=sample_count,json=sampleCount" json:"sample_count,omitempty"`
+	SampleSum            *float64  `protobuf:"fixed64,2,opt,name=sample_sum,json=sampleSum" json:"sample_sum,omitempty"`
+	Bucket               []*Bucket `protobuf:"bytes,3,rep,name=bucket" json:"bucket,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}  `json:"-"`
+	XXX_unrecognized     []byte    `json:"-"`
+	XXX_sizecache        int32     `json:"-"`
+}
+
+func (m *Histogram) Reset()         { *m = Histogram{} }
+func (m *Histogram) String() string { return proto.CompactTextString(m) }
+func (*Histogram) ProtoMessage()    {}
+func (*Histogram) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{6}
+}
+func (m *Histogram) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Histogram.Unmarshal(m, b)
+}
+func (m *Histogram) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Histogram.Marshal(b, m, deterministic)
+}
+func (dst *Histogram) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Histogram.Merge(dst, src)
+}
+func (m *Histogram) XXX_Size() int {
+	return xxx_messageInfo_Histogram.Size(m)
+}
+func (m *Histogram) XXX_DiscardUnknown() {
+	xxx_messageInfo_Histogram.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Histogram proto.InternalMessageInfo
+
+func (m *Histogram) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Histogram) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Histogram) GetBucket() []*Bucket {
+	if m != nil {
+		return m.Bucket
+	}
+	return nil
+}
+
+type Bucket struct {
+	CumulativeCount      *uint64  `protobuf:"varint,1,opt,name=cumulative_count,json=cumulativeCount" json:"cumulative_count,omitempty"`
+	UpperBound           *float64 `protobuf:"fixed64,2,opt,name=upper_bound,json=upperBound" json:"upper_bound,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Bucket) Reset()         { *m = Bucket{} }
+func (m *Bucket) String() string { return proto.CompactTextString(m) }
+func (*Bucket) ProtoMessage()    {}
+func (*Bucket) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{7}
+}
+func (m *Bucket) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Bucket.Unmarshal(m, b)
+}
+func (m *Bucket) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Bucket.Marshal(b, m, deterministic)
+}
+func (dst *Bucket) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Bucket.Merge(dst, src)
+}
+func (m *Bucket) XXX_Size() int {
+	return xxx_messageInfo_Bucket.Size(m)
+}
+func (m *Bucket) XXX_DiscardUnknown() {
+	xxx_messageInfo_Bucket.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Bucket proto.InternalMessageInfo
+
+func (m *Bucket) GetCumulativeCount() uint64 {
+	if m != nil && m.CumulativeCount != nil {
+		return *m.CumulativeCount
+	}
+	return 0
+}
+
+func (m *Bucket) GetUpperBound() float64 {
+	if m != nil && m.UpperBound != nil {
+		return *m.UpperBound
+	}
+	return 0
+}
+
+type Metric struct {
+	Label                []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
+	Gauge                *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
+	Counter              *Counter     `protobuf:"bytes,3,opt,name=counter" json:"counter,omitempty"`
+	Summary              *Summary     `protobuf:"bytes,4,opt,name=summary" json:"summary,omitempty"`
+	Untyped              *Untyped     `protobuf:"bytes,5,opt,name=untyped" json:"untyped,omitempty"`
+	Histogram            *Histogram   `protobuf:"bytes,7,opt,name=histogram" json:"histogram,omitempty"`
+	TimestampMs          *int64       `protobuf:"varint,6,opt,name=timestamp_ms,json=timestampMs" json:"timestamp_ms,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}     `json:"-"`
+	XXX_unrecognized     []byte       `json:"-"`
+	XXX_sizecache        int32        `json:"-"`
+}
+
+func (m *Metric) Reset()         { *m = Metric{} }
+func (m *Metric) String() string { return proto.CompactTextString(m) }
+func (*Metric) ProtoMessage()    {}
+func (*Metric) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{8}
+}
+func (m *Metric) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Metric.Unmarshal(m, b)
+}
+func (m *Metric) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Metric.Marshal(b, m, deterministic)
+}
+func (dst *Metric) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Metric.Merge(dst, src)
+}
+func (m *Metric) XXX_Size() int {
+	return xxx_messageInfo_Metric.Size(m)
+}
+func (m *Metric) XXX_DiscardUnknown() {
+	xxx_messageInfo_Metric.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Metric proto.InternalMessageInfo
+
+func (m *Metric) GetLabel() []*LabelPair {
+	if m != nil {
+		return m.Label
+	}
+	return nil
+}
+
+func (m *Metric) GetGauge() *Gauge {
+	if m != nil {
+		return m.Gauge
+	}
+	return nil
+}
+
+func (m *Metric) GetCounter() *Counter {
+	if m != nil {
+		return m.Counter
+	}
+	return nil
+}
+
+func (m *Metric) GetSummary() *Summary {
+	if m != nil {
+		return m.Summary
+	}
+	return nil
+}
+
+func (m *Metric) GetUntyped() *Untyped {
+	if m != nil {
+		return m.Untyped
+	}
+	return nil
+}
+
+func (m *Metric) GetHistogram() *Histogram {
+	if m != nil {
+		return m.Histogram
+	}
+	return nil
+}
+
+func (m *Metric) GetTimestampMs() int64 {
+	if m != nil && m.TimestampMs != nil {
+		return *m.TimestampMs
+	}
+	return 0
+}
+
+type MetricFamily struct {
+	Name                 *string     `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Help                 *string     `protobuf:"bytes,2,opt,name=help" json:"help,omitempty"`
+	Type                 *MetricType `protobuf:"varint,3,opt,name=type,enum=io.prometheus.client.MetricType" json:"type,omitempty"`
+	Metric               []*Metric   `protobuf:"bytes,4,rep,name=metric" json:"metric,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}    `json:"-"`
+	XXX_unrecognized     []byte      `json:"-"`
+	XXX_sizecache        int32       `json:"-"`
+}
+
+func (m *MetricFamily) Reset()         { *m = MetricFamily{} }
+func (m *MetricFamily) String() string { return proto.CompactTextString(m) }
+func (*MetricFamily) ProtoMessage()    {}
+func (*MetricFamily) Descriptor() ([]byte, []int) {
+	return fileDescriptor_metrics_c97c9a2b9560cb8f, []int{9}
+}
+func (m *MetricFamily) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_MetricFamily.Unmarshal(m, b)
+}
+func (m *MetricFamily) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_MetricFamily.Marshal(b, m, deterministic)
+}
+func (dst *MetricFamily) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_MetricFamily.Merge(dst, src)
+}
+func (m *MetricFamily) XXX_Size() int {
+	return xxx_messageInfo_MetricFamily.Size(m)
+}
+func (m *MetricFamily) XXX_DiscardUnknown() {
+	xxx_messageInfo_MetricFamily.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_MetricFamily proto.InternalMessageInfo
+
+func (m *MetricFamily) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetHelp() string {
+	if m != nil && m.Help != nil {
+		return *m.Help
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetType() MetricType {
+	if m != nil && m.Type != nil {
+		return *m.Type
+	}
+	return MetricType_COUNTER
+}
+
+func (m *MetricFamily) GetMetric() []*Metric {
+	if m != nil {
+		return m.Metric
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*LabelPair)(nil), "io.prometheus.client.LabelPair")
+	proto.RegisterType((*Gauge)(nil), "io.prometheus.client.Gauge")
+	proto.RegisterType((*Counter)(nil), "io.prometheus.client.Counter")
+	proto.RegisterType((*Quantile)(nil), "io.prometheus.client.Quantile")
+	proto.RegisterType((*Summary)(nil), "io.prometheus.client.Summary")
+	proto.RegisterType((*Untyped)(nil), "io.prometheus.client.Untyped")
+	proto.RegisterType((*Histogram)(nil), "io.prometheus.client.Histogram")
+	proto.RegisterType((*Bucket)(nil), "io.prometheus.client.Bucket")
+	proto.RegisterType((*Metric)(nil), "io.prometheus.client.Metric")
+	proto.RegisterType((*MetricFamily)(nil), "io.prometheus.client.MetricFamily")
+	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
+}
+
+func init() { proto.RegisterFile("metrics.proto", fileDescriptor_metrics_c97c9a2b9560cb8f) }
+
+var fileDescriptor_metrics_c97c9a2b9560cb8f = []byte{
+	// 591 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x54, 0x4f, 0x4f, 0xdb, 0x4e,
+	0x14, 0xfc, 0x99, 0xd8, 0x09, 0x7e, 0x86, 0x5f, 0xad, 0x15, 0x07, 0xab, 0x2d, 0x25, 0xcd, 0x89,
+	0xf6, 0x10, 0x54, 0x04, 0xaa, 0x44, 0xdb, 0x03, 0x50, 0x1a, 0x2a, 0xd5, 0x40, 0x37, 0xc9, 0x81,
+	0x5e, 0xac, 0x8d, 0x59, 0x25, 0x56, 0xbd, 0xb6, 0x6b, 0xef, 0x22, 0xe5, 0xdc, 0x43, 0xbf, 0x47,
+	0xbf, 0x68, 0xab, 0xfd, 0xe3, 0x18, 0x24, 0xc3, 0xa9, 0xb7, 0xb7, 0xf3, 0x66, 0xde, 0x8e, 0x77,
+	0xc7, 0x0b, 0x9b, 0x8c, 0xf2, 0x32, 0x89, 0xab, 0x61, 0x51, 0xe6, 0x3c, 0x47, 0x5b, 0x49, 0x2e,
+	0x2b, 0x46, 0xf9, 0x82, 0x8a, 0x6a, 0x18, 0xa7, 0x09, 0xcd, 0xf8, 0xe0, 0x10, 0xdc, 0x2f, 0x64,
+	0x46, 0xd3, 0x2b, 0x92, 0x94, 0x08, 0x81, 0x9d, 0x11, 0x46, 0x03, 0xab, 0x6f, 0xed, 0xba, 0x58,
+	0xd5, 0x68, 0x0b, 0x9c, 0x5b, 0x92, 0x0a, 0x1a, 0xac, 0x29, 0x50, 0x2f, 0x06, 0xdb, 0xe0, 0x8c,
+	0x88, 0x98, 0xdf, 0x69, 0x4b, 0x8d, 0x55, 0xb7, 0x77, 0xa0, 0x77, 0x9a, 0x8b, 0x8c, 0xd3, 0xf2,
+	0x01, 0xc2, 0x7b, 0x58, 0xff, 0x2a, 0x48, 0xc6, 0x93, 0x94, 0xa2, 0xa7, 0xb0, 0xfe, 0xc3, 0xd4,
+	0x86, 0xb4, 0x5a, 0xdf, 0xdf, 0x7d, 0xa5, 0xfe, 0x65, 0x41, 0x6f, 0x2c, 0x18, 0x23, 0xe5, 0x12,
+	0xbd, 0x84, 0x8d, 0x8a, 0xb0, 0x22, 0xa5, 0x51, 0x2c, 0x77, 0x54, 0x13, 0x6c, 0xec, 0x69, 0x4c,
+	0x99, 0x40, 0xdb, 0x00, 0x86, 0x52, 0x09, 0x66, 0x26, 0xb9, 0x1a, 0x19, 0x0b, 0x86, 0x8e, 0xee,
+	0xec, 0xdf, 0xe9, 0x77, 0x76, 0xbd, 0xfd, 0x17, 0xc3, 0xb6, 0xb3, 0x1a, 0xd6, 0x8e, 0x1b, 0x7f,
+	0xf2, 0x43, 0xa7, 0x19, 0x5f, 0x16, 0xf4, 0xe6, 0x81, 0x0f, 0xfd, 0x69, 0x81, 0x7b, 0x9e, 0x54,
+	0x3c, 0x9f, 0x97, 0x84, 0xfd, 0x03, 0xb3, 0x07, 0xd0, 0x9d, 0x89, 0xf8, 0x3b, 0xe5, 0xc6, 0xea,
+	0xf3, 0x76, 0xab, 0x27, 0x8a, 0x83, 0x0d, 0x77, 0x30, 0x81, 0xae, 0x46, 0xd0, 0x2b, 0xf0, 0x63,
+	0xc1, 0x44, 0x4a, 0x78, 0x72, 0x7b, 0xdf, 0xc5, 0x93, 0x06, 0xd7, 0x4e, 0x76, 0xc0, 0x13, 0x45,
+	0x41, 0xcb, 0x68, 0x96, 0x8b, 0xec, 0xc6, 0x58, 0x01, 0x05, 0x9d, 0x48, 0x64, 0xf0, 0x67, 0x0d,
+	0xba, 0xa1, 0xca, 0x18, 0x3a, 0x04, 0x27, 0x95, 0x31, 0x0a, 0x2c, 0xe5, 0x6a, 0xa7, 0xdd, 0xd5,
+	0x2a, 0x69, 0x58, 0xb3, 0xd1, 0x1b, 0x70, 0xe6, 0x32, 0x46, 0x6a, 0xb8, 0xb7, 0xff, 0xac, 0x5d,
+	0xa6, 0x92, 0x86, 0x35, 0x13, 0xbd, 0x85, 0x5e, 0xac, 0xa3, 0x15, 0x74, 0x94, 0x68, 0xbb, 0x5d,
+	0x64, 0xf2, 0x87, 0x6b, 0xb6, 0x14, 0x56, 0x3a, 0x33, 0x81, 0xfd, 0x98, 0xd0, 0x04, 0x0b, 0xd7,
+	0x6c, 0x29, 0x14, 0xfa, 0x8e, 0x03, 0xe7, 0x31, 0xa1, 0x09, 0x02, 0xae, 0xd9, 0xe8, 0x03, 0xb8,
+	0x8b, 0xfa, 0xea, 0x83, 0x9e, 0x92, 0x3e, 0x70, 0x30, 0xab, 0x84, 0xe0, 0x46, 0x21, 0xc3, 0xc2,
+	0x13, 0x46, 0x2b, 0x4e, 0x58, 0x11, 0xb1, 0x2a, 0xe8, 0xf6, 0xad, 0xdd, 0x0e, 0xf6, 0x56, 0x58,
+	0x58, 0x0d, 0x7e, 0x5b, 0xb0, 0xa1, 0x6f, 0xe0, 0x13, 0x61, 0x49, 0xba, 0x6c, 0xfd, 0x83, 0x11,
+	0xd8, 0x0b, 0x9a, 0x16, 0xe6, 0x07, 0x56, 0x35, 0x3a, 0x00, 0x5b, 0x7a, 0x54, 0x47, 0xf8, 0xff,
+	0x7e, 0xbf, 0xdd, 0x95, 0x9e, 0x3c, 0x59, 0x16, 0x14, 0x2b, 0xb6, 0x0c, 0x9f, 0x7e, 0x53, 0x02,
+	0xfb, 0xb1, 0xf0, 0x69, 0x1d, 0x36, 0xdc, 0xd7, 0x21, 0x40, 0x33, 0x09, 0x79, 0xd0, 0x3b, 0xbd,
+	0x9c, 0x5e, 0x4c, 0xce, 0xb0, 0xff, 0x1f, 0x72, 0xc1, 0x19, 0x1d, 0x4f, 0x47, 0x67, 0xbe, 0x25,
+	0xf1, 0xf1, 0x34, 0x0c, 0x8f, 0xf1, 0xb5, 0xbf, 0x26, 0x17, 0xd3, 0x8b, 0xc9, 0xf5, 0xd5, 0xd9,
+	0x47, 0xbf, 0x83, 0x36, 0xc1, 0x3d, 0xff, 0x3c, 0x9e, 0x5c, 0x8e, 0xf0, 0x71, 0xe8, 0xdb, 0x27,
+	0x18, 0x5a, 0x5f, 0xb2, 0x6f, 0x47, 0xf3, 0x84, 0x2f, 0xc4, 0x6c, 0x18, 0xe7, 0x6c, 0xaf, 0xe9,
+	0xee, 0xe9, 0x6e, 0xc4, 0xf2, 0x1b, 0x9a, 0xee, 0xcd, 0xf3, 0x77, 0x49, 0x1e, 0x35, 0xdd, 0x48,
+	0x77, 0xff, 0x06, 0x00, 0x00, 0xff, 0xff, 0x45, 0x21, 0x7f, 0x64, 0x2b, 0x05, 0x00, 0x00,
+}
diff --git a/vendor/github.com/prometheus/client_model/ruby/LICENSE b/vendor/github.com/prometheus/client_model/ruby/LICENSE
new file mode 100644
index 0000000000..11069edd79
--- /dev/null
+++ b/vendor/github.com/prometheus/client_model/ruby/LICENSE
@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
+
+   "Licensor" shall mean the copyright owner or entity authorized by
+   the copyright owner that is granting the License.
+
+   "Legal Entity" shall mean the union of the acting entity and all
+   other entities that control, are controlled by, or are under common
+   control with that entity. For the purposes of this definition,
+   "control" means (i) the power, direct or indirect, to cause the
+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
+   exercising permissions granted by this License.
+
+   "Source" form shall mean the preferred form for making modifications,
+   including but not limited to software source code, documentation
+   source, and configuration files.
+
+   "Object" form shall mean any form resulting from mechanical
+   transformation or translation of a Source form, including but
+   not limited to compiled object code, generated documentation,
+   and conversions to other media types.
+
+   "Work" shall mean the work of authorship, whether in Source or
+   Object form, made available under the License, as indicated by a
+   copyright notice that is included in or attached to the work
+   (an example is provided in the Appendix below).
+
+   "Derivative Works" shall mean any work, whether in Source or Object
+   form, that is based on (or derived from) the Work and for which the
+   editorial revisions, annotations, elaborations, or other modifications
+   represent, as a whole, an original work of authorship. For the purposes
+   of this License, Derivative Works shall not include works that remain
+   separable from, or merely link (or bind by name) to the interfaces of,
+   the Work and Derivative Works thereof.
+
+   "Contribution" shall mean any work of authorship, including
+   the original version of the Work and any modifications or additions
+   to that Work or Derivative Works thereof, that is intentionally
+   submitted to Licensor for inclusion in the Work by the copyright owner
+   or by an individual or Legal Entity authorized to submit on behalf of
+   the copyright owner. For the purposes of this definition, "submitted"
+   means any form of electronic, verbal, or written communication sent
+   to the Licensor or its representatives, including but not limited to
+   communication on electronic mailing lists, source code control systems,
+   and issue tracking systems that are managed by, or on behalf of, the
+   Licensor for the purpose of discussing and improving the Work, but
+   excluding communication that is conspicuously marked or otherwise
+   designated in writing by the copyright owner as "Not a Contribution."
+
+   "Contributor" shall mean Licensor and any individual or Legal Entity
+   on behalf of whom a Contribution has been received by Licensor and
+   subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   copyright license to reproduce, prepare Derivative Works of,
+   publicly display, publicly perform, sublicense, and distribute the
+   Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of
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+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   (except as stated in this section) patent license to make, have made,
+   use, offer to sell, sell, import, and otherwise transfer the Work,
+   where such license applies only to those patent claims licensable
+   by such Contributor that are necessarily infringed by their
+   Contribution(s) alone or by combination of their Contribution(s)
+   with the Work to which such Contribution(s) was submitted. If You
+   institute patent litigation against any entity (including a
+   cross-claim or counterclaim in a lawsuit) alleging that the Work
+   or a Contribution incorporated within the Work constitutes direct
+   or contributory patent infringement, then any patent licenses
+   granted to You under this License for that Work shall terminate
+   as of the date such litigation is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the
+   Work or Derivative Works thereof in any medium, with or without
+   modifications, and in Source or Object form, provided that You
+   meet the following conditions:
+
+   (a) You must give any other recipients of the Work or
+       Derivative Works a copy of this License; and
+
+   (b) You must cause any modified files to carry prominent notices
+       stating that You changed the files; and
+
+   (c) You must retain, in the Source form of any Derivative Works
+       that You distribute, all copyright, patent, trademark, and
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+       the Derivative Works; and
+
+   (d) If the Work includes a "NOTICE" text file as part of its
+       distribution, then any Derivative Works that You distribute must
+       include a readable copy of the attribution notices contained
+       within such NOTICE file, excluding those notices that do not
+       pertain to any part of the Derivative Works, in at least one
+       of the following places: within a NOTICE text file distributed
+       as part of the Derivative Works; within the Source form or
+       documentation, if provided along with the Derivative Works; or,
+       within a display generated by the Derivative Works, if and
+       wherever such third-party notices normally appear. The contents
+       of the NOTICE file are for informational purposes only and
+       do not modify the License. You may add Your own attribution
+       notices within Derivative Works that You distribute, alongside
+       or as an addendum to the NOTICE text from the Work, provided
+       that such additional attribution notices cannot be construed
+       as modifying the License.
+
+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
+   for use, reproduction, or distribution of Your modifications, or
+   for any such Derivative Works as a whole, provided Your use,
+   reproduction, and distribution of the Work otherwise complies with
+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
+   except as required for reasonable and customary use in describing the
+   origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied, including, without limitation, any warranties or conditions
+   of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+   PARTICULAR PURPOSE. You are solely responsible for determining the
+   appropriateness of using or redistributing the Work and assume any
+   risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
+   negligent acts) or agreed to in writing, shall any Contributor be
+   liable to You for damages, including any direct, indirect, special,
+   incidental, or consequential damages of any character arising as a
+   result of this License or out of the use or inability to use the
+   Work (including but not limited to damages for loss of goodwill,
+   work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses), even if such Contributor
+   has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+   the Work or Derivative Works thereof, You may choose to offer,
+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
+   boilerplate notice, with the fields enclosed by brackets "[]"
+   replaced with your own identifying information. (Don't include
+   the brackets!)  The text should be enclosed in the appropriate
+   comment syntax for the file format. We also recommend that a
+   file or class name and description of purpose be included on the
+   same "printed page" as the copyright notice for easier
+   identification within third-party archives.
+
+Copyright [yyyy] [name of copyright owner]
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
diff --git a/vendor/github.com/prometheus/common/LICENSE b/vendor/github.com/prometheus/common/LICENSE
new file mode 100644
index 0000000000..261eeb9e9f
--- /dev/null
+++ b/vendor/github.com/prometheus/common/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/prometheus/common/NOTICE b/vendor/github.com/prometheus/common/NOTICE
new file mode 100644
index 0000000000..636a2c1a5e
--- /dev/null
+++ b/vendor/github.com/prometheus/common/NOTICE
@@ -0,0 +1,5 @@
+Common libraries shared by Prometheus Go components.
+Copyright 2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
diff --git a/vendor/github.com/prometheus/common/expfmt/decode.go b/vendor/github.com/prometheus/common/expfmt/decode.go
new file mode 100644
index 0000000000..c092723e84
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/decode.go
@@ -0,0 +1,429 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"mime"
+	"net/http"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+	"github.com/prometheus/common/model"
+)
+
+// Decoder types decode an input stream into metric families.
+type Decoder interface {
+	Decode(*dto.MetricFamily) error
+}
+
+// DecodeOptions contains options used by the Decoder and in sample extraction.
+type DecodeOptions struct {
+	// Timestamp is added to each value from the stream that has no explicit timestamp set.
+	Timestamp model.Time
+}
+
+// ResponseFormat extracts the correct format from a HTTP response header.
+// If no matching format can be found FormatUnknown is returned.
+func ResponseFormat(h http.Header) Format {
+	ct := h.Get(hdrContentType)
+
+	mediatype, params, err := mime.ParseMediaType(ct)
+	if err != nil {
+		return FmtUnknown
+	}
+
+	const textType = "text/plain"
+
+	switch mediatype {
+	case ProtoType:
+		if p, ok := params["proto"]; ok && p != ProtoProtocol {
+			return FmtUnknown
+		}
+		if e, ok := params["encoding"]; ok && e != "delimited" {
+			return FmtUnknown
+		}
+		return FmtProtoDelim
+
+	case textType:
+		if v, ok := params["version"]; ok && v != TextVersion {
+			return FmtUnknown
+		}
+		return FmtText
+	}
+
+	return FmtUnknown
+}
+
+// NewDecoder returns a new decoder based on the given input format.
+// If the input format does not imply otherwise, a text format decoder is returned.
+func NewDecoder(r io.Reader, format Format) Decoder {
+	switch format {
+	case FmtProtoDelim:
+		return &protoDecoder{r: r}
+	}
+	return &textDecoder{r: r}
+}
+
+// protoDecoder implements the Decoder interface for protocol buffers.
+type protoDecoder struct {
+	r io.Reader
+}
+
+// Decode implements the Decoder interface.
+func (d *protoDecoder) Decode(v *dto.MetricFamily) error {
+	_, err := pbutil.ReadDelimited(d.r, v)
+	if err != nil {
+		return err
+	}
+	if !model.IsValidMetricName(model.LabelValue(v.GetName())) {
+		return fmt.Errorf("invalid metric name %q", v.GetName())
+	}
+	for _, m := range v.GetMetric() {
+		if m == nil {
+			continue
+		}
+		for _, l := range m.GetLabel() {
+			if l == nil {
+				continue
+			}
+			if !model.LabelValue(l.GetValue()).IsValid() {
+				return fmt.Errorf("invalid label value %q", l.GetValue())
+			}
+			if !model.LabelName(l.GetName()).IsValid() {
+				return fmt.Errorf("invalid label name %q", l.GetName())
+			}
+		}
+	}
+	return nil
+}
+
+// textDecoder implements the Decoder interface for the text protocol.
+type textDecoder struct {
+	r    io.Reader
+	p    TextParser
+	fams []*dto.MetricFamily
+}
+
+// Decode implements the Decoder interface.
+func (d *textDecoder) Decode(v *dto.MetricFamily) error {
+	// TODO(fabxc): Wrap this as a line reader to make streaming safer.
+	if len(d.fams) == 0 {
+		// No cached metric families, read everything and parse metrics.
+		fams, err := d.p.TextToMetricFamilies(d.r)
+		if err != nil {
+			return err
+		}
+		if len(fams) == 0 {
+			return io.EOF
+		}
+		d.fams = make([]*dto.MetricFamily, 0, len(fams))
+		for _, f := range fams {
+			d.fams = append(d.fams, f)
+		}
+	}
+
+	*v = *d.fams[0]
+	d.fams = d.fams[1:]
+
+	return nil
+}
+
+// SampleDecoder wraps a Decoder to extract samples from the metric families
+// decoded by the wrapped Decoder.
+type SampleDecoder struct {
+	Dec  Decoder
+	Opts *DecodeOptions
+
+	f dto.MetricFamily
+}
+
+// Decode calls the Decode method of the wrapped Decoder and then extracts the
+// samples from the decoded MetricFamily into the provided model.Vector.
+func (sd *SampleDecoder) Decode(s *model.Vector) error {
+	err := sd.Dec.Decode(&sd.f)
+	if err != nil {
+		return err
+	}
+	*s, err = extractSamples(&sd.f, sd.Opts)
+	return err
+}
+
+// ExtractSamples builds a slice of samples from the provided metric
+// families. If an error occurrs during sample extraction, it continues to
+// extract from the remaining metric families. The returned error is the last
+// error that has occurred.
+func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) (model.Vector, error) {
+	var (
+		all     model.Vector
+		lastErr error
+	)
+	for _, f := range fams {
+		some, err := extractSamples(f, o)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		all = append(all, some...)
+	}
+	return all, lastErr
+}
+
+func extractSamples(f *dto.MetricFamily, o *DecodeOptions) (model.Vector, error) {
+	switch f.GetType() {
+	case dto.MetricType_COUNTER:
+		return extractCounter(o, f), nil
+	case dto.MetricType_GAUGE:
+		return extractGauge(o, f), nil
+	case dto.MetricType_SUMMARY:
+		return extractSummary(o, f), nil
+	case dto.MetricType_UNTYPED:
+		return extractUntyped(o, f), nil
+	case dto.MetricType_HISTOGRAM:
+		return extractHistogram(o, f), nil
+	}
+	return nil, fmt.Errorf("expfmt.extractSamples: unknown metric family type %v", f.GetType())
+}
+
+func extractCounter(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Counter == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Counter.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractGauge(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Gauge == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Gauge.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractUntyped(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Untyped == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Untyped.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractSummary(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Summary == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		for _, q := range m.Summary.Quantile {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			// BUG(matt): Update other names to "quantile".
+			lset[model.LabelName(model.QuantileLabel)] = model.LabelValue(fmt.Sprint(q.GetQuantile()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetValue()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleCount()),
+			Timestamp: timestamp,
+		})
+	}
+
+	return samples
+}
+
+func extractHistogram(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Histogram == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		infSeen := false
+
+		for _, q := range m.Histogram.Bucket {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue(fmt.Sprint(q.GetUpperBound()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			if math.IsInf(q.GetUpperBound(), +1) {
+				infSeen = true
+			}
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetCumulativeCount()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		count := &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleCount()),
+			Timestamp: timestamp,
+		}
+		samples = append(samples, count)
+
+		if !infSeen {
+			// Append an infinity bucket sample.
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue("+Inf")
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     count.Value,
+				Timestamp: timestamp,
+			})
+		}
+	}
+
+	return samples
+}
diff --git a/vendor/github.com/prometheus/common/expfmt/encode.go b/vendor/github.com/prometheus/common/expfmt/encode.go
new file mode 100644
index 0000000000..11839ed65c
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/encode.go
@@ -0,0 +1,88 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+	"github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Encoder types encode metric families into an underlying wire protocol.
+type Encoder interface {
+	Encode(*dto.MetricFamily) error
+}
+
+type encoder func(*dto.MetricFamily) error
+
+func (e encoder) Encode(v *dto.MetricFamily) error {
+	return e(v)
+}
+
+// Negotiate returns the Content-Type based on the given Accept header.
+// If no appropriate accepted type is found, FmtText is returned.
+func Negotiate(h http.Header) Format {
+	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
+		// Check for protocol buffer
+		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
+			switch ac.Params["encoding"] {
+			case "delimited":
+				return FmtProtoDelim
+			case "text":
+				return FmtProtoText
+			case "compact-text":
+				return FmtProtoCompact
+			}
+		}
+		// Check for text format.
+		ver := ac.Params["version"]
+		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
+			return FmtText
+		}
+	}
+	return FmtText
+}
+
+// NewEncoder returns a new encoder based on content type negotiation.
+func NewEncoder(w io.Writer, format Format) Encoder {
+	switch format {
+	case FmtProtoDelim:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := pbutil.WriteDelimited(w, v)
+			return err
+		})
+	case FmtProtoCompact:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, v.String())
+			return err
+		})
+	case FmtProtoText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
+			return err
+		})
+	case FmtText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := MetricFamilyToText(w, v)
+			return err
+		})
+	}
+	panic("expfmt.NewEncoder: unknown format")
+}
diff --git a/vendor/github.com/prometheus/common/expfmt/expfmt.go b/vendor/github.com/prometheus/common/expfmt/expfmt.go
new file mode 100644
index 0000000000..c71bcb9816
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/expfmt.go
@@ -0,0 +1,38 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package expfmt contains tools for reading and writing Prometheus metrics.
+package expfmt
+
+// Format specifies the HTTP content type of the different wire protocols.
+type Format string
+
+// Constants to assemble the Content-Type values for the different wire protocols.
+const (
+	TextVersion   = "0.0.4"
+	ProtoType     = `application/vnd.google.protobuf`
+	ProtoProtocol = `io.prometheus.client.MetricFamily`
+	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
+
+	// The Content-Type values for the different wire protocols.
+	FmtUnknown      Format = `<unknown>`
+	FmtText         Format = `text/plain; version=` + TextVersion + `; charset=utf-8`
+	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
+	FmtProtoText    Format = ProtoFmt + ` encoding=text`
+	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
+)
+
+const (
+	hdrContentType = "Content-Type"
+	hdrAccept      = "Accept"
+)
diff --git a/vendor/github.com/prometheus/common/expfmt/fuzz.go b/vendor/github.com/prometheus/common/expfmt/fuzz.go
new file mode 100644
index 0000000000..dc2eedeefc
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/fuzz.go
@@ -0,0 +1,36 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Build only when actually fuzzing
+// +build gofuzz
+
+package expfmt
+
+import "bytes"
+
+// Fuzz text metric parser with with github.com/dvyukov/go-fuzz:
+//
+//     go-fuzz-build github.com/prometheus/common/expfmt
+//     go-fuzz -bin expfmt-fuzz.zip -workdir fuzz
+//
+// Further input samples should go in the folder fuzz/corpus.
+func Fuzz(in []byte) int {
+	parser := TextParser{}
+	_, err := parser.TextToMetricFamilies(bytes.NewReader(in))
+
+	if err != nil {
+		return 0
+	}
+
+	return 1
+}
diff --git a/vendor/github.com/prometheus/common/expfmt/text_create.go b/vendor/github.com/prometheus/common/expfmt/text_create.go
new file mode 100644
index 0000000000..8e473d0fe9
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/text_create.go
@@ -0,0 +1,468 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+	"sync"
+
+	"github.com/prometheus/common/model"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// enhancedWriter has all the enhanced write functions needed here. bytes.Buffer
+// implements it.
+type enhancedWriter interface {
+	io.Writer
+	WriteRune(r rune) (n int, err error)
+	WriteString(s string) (n int, err error)
+	WriteByte(c byte) error
+}
+
+const (
+	initialBufSize    = 512
+	initialNumBufSize = 24
+)
+
+var (
+	bufPool = sync.Pool{
+		New: func() interface{} {
+			return bytes.NewBuffer(make([]byte, 0, initialBufSize))
+		},
+	}
+	numBufPool = sync.Pool{
+		New: func() interface{} {
+			b := make([]byte, 0, initialNumBufSize)
+			return &b
+		},
+	}
+)
+
+// MetricFamilyToText converts a MetricFamily proto message into text format and
+// writes the resulting lines to 'out'. It returns the number of bytes written
+// and any error encountered. The output will have the same order as the input,
+// no further sorting is performed. Furthermore, this function assumes the input
+// is already sanitized and does not perform any sanity checks. If the input
+// contains duplicate metrics or invalid metric or label names, the conversion
+// will result in invalid text format output.
+//
+// This method fulfills the type 'prometheus.encoder'.
+func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (written int, err error) {
+	// Fail-fast checks.
+	if len(in.Metric) == 0 {
+		return 0, fmt.Errorf("MetricFamily has no metrics: %s", in)
+	}
+	name := in.GetName()
+	if name == "" {
+		return 0, fmt.Errorf("MetricFamily has no name: %s", in)
+	}
+
+	// Try the interface upgrade. If it doesn't work, we'll use a
+	// bytes.Buffer from the sync.Pool and write out its content to out in a
+	// single go in the end.
+	w, ok := out.(enhancedWriter)
+	if !ok {
+		b := bufPool.Get().(*bytes.Buffer)
+		b.Reset()
+		w = b
+		defer func() {
+			bWritten, bErr := out.Write(b.Bytes())
+			written = bWritten
+			if err == nil {
+				err = bErr
+			}
+			bufPool.Put(b)
+		}()
+	}
+
+	var n int
+
+	// Comments, first HELP, then TYPE.
+	if in.Help != nil {
+		n, err = w.WriteString("# HELP ")
+		written += n
+		if err != nil {
+			return
+		}
+		n, err = w.WriteString(name)
+		written += n
+		if err != nil {
+			return
+		}
+		err = w.WriteByte(' ')
+		written++
+		if err != nil {
+			return
+		}
+		n, err = writeEscapedString(w, *in.Help, false)
+		written += n
+		if err != nil {
+			return
+		}
+		err = w.WriteByte('\n')
+		written++
+		if err != nil {
+			return
+		}
+	}
+	n, err = w.WriteString("# TYPE ")
+	written += n
+	if err != nil {
+		return
+	}
+	n, err = w.WriteString(name)
+	written += n
+	if err != nil {
+		return
+	}
+	metricType := in.GetType()
+	switch metricType {
+	case dto.MetricType_COUNTER:
+		n, err = w.WriteString(" counter\n")
+	case dto.MetricType_GAUGE:
+		n, err = w.WriteString(" gauge\n")
+	case dto.MetricType_SUMMARY:
+		n, err = w.WriteString(" summary\n")
+	case dto.MetricType_UNTYPED:
+		n, err = w.WriteString(" untyped\n")
+	case dto.MetricType_HISTOGRAM:
+		n, err = w.WriteString(" histogram\n")
+	default:
+		return written, fmt.Errorf("unknown metric type %s", metricType.String())
+	}
+	written += n
+	if err != nil {
+		return
+	}
+
+	// Finally the samples, one line for each.
+	for _, metric := range in.Metric {
+		switch metricType {
+		case dto.MetricType_COUNTER:
+			if metric.Counter == nil {
+				return written, fmt.Errorf(
+					"expected counter in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				w, name, "", metric, "", 0,
+				metric.Counter.GetValue(),
+			)
+		case dto.MetricType_GAUGE:
+			if metric.Gauge == nil {
+				return written, fmt.Errorf(
+					"expected gauge in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				w, name, "", metric, "", 0,
+				metric.Gauge.GetValue(),
+			)
+		case dto.MetricType_UNTYPED:
+			if metric.Untyped == nil {
+				return written, fmt.Errorf(
+					"expected untyped in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				w, name, "", metric, "", 0,
+				metric.Untyped.GetValue(),
+			)
+		case dto.MetricType_SUMMARY:
+			if metric.Summary == nil {
+				return written, fmt.Errorf(
+					"expected summary in metric %s %s", name, metric,
+				)
+			}
+			for _, q := range metric.Summary.Quantile {
+				n, err = writeSample(
+					w, name, "", metric,
+					model.QuantileLabel, q.GetQuantile(),
+					q.GetValue(),
+				)
+				written += n
+				if err != nil {
+					return
+				}
+			}
+			n, err = writeSample(
+				w, name, "_sum", metric, "", 0,
+				metric.Summary.GetSampleSum(),
+			)
+			written += n
+			if err != nil {
+				return
+			}
+			n, err = writeSample(
+				w, name, "_count", metric, "", 0,
+				float64(metric.Summary.GetSampleCount()),
+			)
+		case dto.MetricType_HISTOGRAM:
+			if metric.Histogram == nil {
+				return written, fmt.Errorf(
+					"expected histogram in metric %s %s", name, metric,
+				)
+			}
+			infSeen := false
+			for _, b := range metric.Histogram.Bucket {
+				n, err = writeSample(
+					w, name, "_bucket", metric,
+					model.BucketLabel, b.GetUpperBound(),
+					float64(b.GetCumulativeCount()),
+				)
+				written += n
+				if err != nil {
+					return
+				}
+				if math.IsInf(b.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeSample(
+					w, name, "_bucket", metric,
+					model.BucketLabel, math.Inf(+1),
+					float64(metric.Histogram.GetSampleCount()),
+				)
+				written += n
+				if err != nil {
+					return
+				}
+			}
+			n, err = writeSample(
+				w, name, "_sum", metric, "", 0,
+				metric.Histogram.GetSampleSum(),
+			)
+			written += n
+			if err != nil {
+				return
+			}
+			n, err = writeSample(
+				w, name, "_count", metric, "", 0,
+				float64(metric.Histogram.GetSampleCount()),
+			)
+		default:
+			return written, fmt.Errorf(
+				"unexpected type in metric %s %s", name, metric,
+			)
+		}
+		written += n
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// writeSample writes a single sample in text format to w, given the metric
+// name, the metric proto message itself, optionally an additional label name
+// with a float64 value (use empty string as label name if not required), and
+// the value. The function returns the number of bytes written and any error
+// encountered.
+func writeSample(
+	w enhancedWriter,
+	name, suffix string,
+	metric *dto.Metric,
+	additionalLabelName string, additionalLabelValue float64,
+	value float64,
+) (int, error) {
+	var written int
+	n, err := w.WriteString(name)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if suffix != "" {
+		n, err = w.WriteString(suffix)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err = writeLabelPairs(
+		w, metric.Label, additionalLabelName, additionalLabelValue,
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	err = w.WriteByte(' ')
+	written++
+	if err != nil {
+		return written, err
+	}
+	n, err = writeFloat(w, value)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if metric.TimestampMs != nil {
+		err = w.WriteByte(' ')
+		written++
+		if err != nil {
+			return written, err
+		}
+		n, err = writeInt(w, *metric.TimestampMs)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	err = w.WriteByte('\n')
+	written++
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// writeLabelPairs converts a slice of LabelPair proto messages plus the
+// explicitly given additional label pair into text formatted as required by the
+// text format and writes it to 'w'. An empty slice in combination with an empty
+// string 'additionalLabelName' results in nothing being written. Otherwise, the
+// label pairs are written, escaped as required by the text format, and enclosed
+// in '{...}'. The function returns the number of bytes written and any error
+// encountered.
+func writeLabelPairs(
+	w enhancedWriter,
+	in []*dto.LabelPair,
+	additionalLabelName string, additionalLabelValue float64,
+) (int, error) {
+	if len(in) == 0 && additionalLabelName == "" {
+		return 0, nil
+	}
+	var (
+		written   int
+		separator byte = '{'
+	)
+	for _, lp := range in {
+		err := w.WriteByte(separator)
+		written++
+		if err != nil {
+			return written, err
+		}
+		n, err := w.WriteString(lp.GetName())
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = w.WriteString(`="`)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = writeEscapedString(w, lp.GetValue(), true)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		err = w.WriteByte('"')
+		written++
+		if err != nil {
+			return written, err
+		}
+		separator = ','
+	}
+	if additionalLabelName != "" {
+		err := w.WriteByte(separator)
+		written++
+		if err != nil {
+			return written, err
+		}
+		n, err := w.WriteString(additionalLabelName)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = w.WriteString(`="`)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		n, err = writeFloat(w, additionalLabelValue)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		err = w.WriteByte('"')
+		written++
+		if err != nil {
+			return written, err
+		}
+	}
+	err := w.WriteByte('}')
+	written++
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// writeEscapedString replaces '\' by '\\', new line character by '\n', and - if
+// includeDoubleQuote is true - '"' by '\"'.
+var (
+	escaper       = strings.NewReplacer("\\", `\\`, "\n", `\n`)
+	quotedEscaper = strings.NewReplacer("\\", `\\`, "\n", `\n`, "\"", `\"`)
+)
+
+func writeEscapedString(w enhancedWriter, v string, includeDoubleQuote bool) (int, error) {
+	if includeDoubleQuote {
+		return quotedEscaper.WriteString(w, v)
+	} else {
+		return escaper.WriteString(w, v)
+	}
+}
+
+// writeFloat is equivalent to fmt.Fprint with a float64 argument but hardcodes
+// a few common cases for increased efficiency. For non-hardcoded cases, it uses
+// strconv.AppendFloat to avoid allocations, similar to writeInt.
+func writeFloat(w enhancedWriter, f float64) (int, error) {
+	switch {
+	case f == 1:
+		return 1, w.WriteByte('1')
+	case f == 0:
+		return 1, w.WriteByte('0')
+	case f == -1:
+		return w.WriteString("-1")
+	case math.IsNaN(f):
+		return w.WriteString("NaN")
+	case math.IsInf(f, +1):
+		return w.WriteString("+Inf")
+	case math.IsInf(f, -1):
+		return w.WriteString("-Inf")
+	default:
+		bp := numBufPool.Get().(*[]byte)
+		*bp = strconv.AppendFloat((*bp)[:0], f, 'g', -1, 64)
+		written, err := w.Write(*bp)
+		numBufPool.Put(bp)
+		return written, err
+	}
+}
+
+// writeInt is equivalent to fmt.Fprint with an int64 argument but uses
+// strconv.AppendInt with a byte slice taken from a sync.Pool to avoid
+// allocations.
+func writeInt(w enhancedWriter, i int64) (int, error) {
+	bp := numBufPool.Get().(*[]byte)
+	*bp = strconv.AppendInt((*bp)[:0], i, 10)
+	written, err := w.Write(*bp)
+	numBufPool.Put(bp)
+	return written, err
+}
diff --git a/vendor/github.com/prometheus/common/expfmt/text_parse.go b/vendor/github.com/prometheus/common/expfmt/text_parse.go
new file mode 100644
index 0000000000..ec3d86ba7c
--- /dev/null
+++ b/vendor/github.com/prometheus/common/expfmt/text_parse.go
@@ -0,0 +1,757 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/model"
+)
+
+// A stateFn is a function that represents a state in a state machine. By
+// executing it, the state is progressed to the next state. The stateFn returns
+// another stateFn, which represents the new state. The end state is represented
+// by nil.
+type stateFn func() stateFn
+
+// ParseError signals errors while parsing the simple and flat text-based
+// exchange format.
+type ParseError struct {
+	Line int
+	Msg  string
+}
+
+// Error implements the error interface.
+func (e ParseError) Error() string {
+	return fmt.Sprintf("text format parsing error in line %d: %s", e.Line, e.Msg)
+}
+
+// TextParser is used to parse the simple and flat text-based exchange format. Its
+// zero value is ready to use.
+type TextParser struct {
+	metricFamiliesByName map[string]*dto.MetricFamily
+	buf                  *bufio.Reader // Where the parsed input is read through.
+	err                  error         // Most recent error.
+	lineCount            int           // Tracks the line count for error messages.
+	currentByte          byte          // The most recent byte read.
+	currentToken         bytes.Buffer  // Re-used each time a token has to be gathered from multiple bytes.
+	currentMF            *dto.MetricFamily
+	currentMetric        *dto.Metric
+	currentLabelPair     *dto.LabelPair
+
+	// The remaining member variables are only used for summaries/histograms.
+	currentLabels map[string]string // All labels including '__name__' but excluding 'quantile'/'le'
+	// Summary specific.
+	summaries       map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentQuantile float64
+	// Histogram specific.
+	histograms    map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentBucket float64
+	// These tell us if the currently processed line ends on '_count' or
+	// '_sum' respectively and belong to a summary/histogram, representing the sample
+	// count and sum of that summary/histogram.
+	currentIsSummaryCount, currentIsSummarySum     bool
+	currentIsHistogramCount, currentIsHistogramSum bool
+}
+
+// TextToMetricFamilies reads 'in' as the simple and flat text-based exchange
+// format and creates MetricFamily proto messages. It returns the MetricFamily
+// proto messages in a map where the metric names are the keys, along with any
+// error encountered.
+//
+// If the input contains duplicate metrics (i.e. lines with the same metric name
+// and exactly the same label set), the resulting MetricFamily will contain
+// duplicate Metric proto messages. Similar is true for duplicate label
+// names. Checks for duplicates have to be performed separately, if required.
+// Also note that neither the metrics within each MetricFamily are sorted nor
+// the label pairs within each Metric. Sorting is not required for the most
+// frequent use of this method, which is sample ingestion in the Prometheus
+// server. However, for presentation purposes, you might want to sort the
+// metrics, and in some cases, you must sort the labels, e.g. for consumption by
+// the metric family injection hook of the Prometheus registry.
+//
+// Summaries and histograms are rather special beasts. You would probably not
+// use them in the simple text format anyway. This method can deal with
+// summaries and histograms if they are presented in exactly the way the
+// text.Create function creates them.
+//
+// This method must not be called concurrently. If you want to parse different
+// input concurrently, instantiate a separate Parser for each goroutine.
+func (p *TextParser) TextToMetricFamilies(in io.Reader) (map[string]*dto.MetricFamily, error) {
+	p.reset(in)
+	for nextState := p.startOfLine; nextState != nil; nextState = nextState() {
+		// Magic happens here...
+	}
+	// Get rid of empty metric families.
+	for k, mf := range p.metricFamiliesByName {
+		if len(mf.GetMetric()) == 0 {
+			delete(p.metricFamiliesByName, k)
+		}
+	}
+	// If p.err is io.EOF now, we have run into a premature end of the input
+	// stream. Turn this error into something nicer and more
+	// meaningful. (io.EOF is often used as a signal for the legitimate end
+	// of an input stream.)
+	if p.err == io.EOF {
+		p.parseError("unexpected end of input stream")
+	}
+	return p.metricFamiliesByName, p.err
+}
+
+func (p *TextParser) reset(in io.Reader) {
+	p.metricFamiliesByName = map[string]*dto.MetricFamily{}
+	if p.buf == nil {
+		p.buf = bufio.NewReader(in)
+	} else {
+		p.buf.Reset(in)
+	}
+	p.err = nil
+	p.lineCount = 0
+	if p.summaries == nil || len(p.summaries) > 0 {
+		p.summaries = map[uint64]*dto.Metric{}
+	}
+	if p.histograms == nil || len(p.histograms) > 0 {
+		p.histograms = map[uint64]*dto.Metric{}
+	}
+	p.currentQuantile = math.NaN()
+	p.currentBucket = math.NaN()
+}
+
+// startOfLine represents the state where the next byte read from p.buf is the
+// start of a line (or whitespace leading up to it).
+func (p *TextParser) startOfLine() stateFn {
+	p.lineCount++
+	if p.skipBlankTab(); p.err != nil {
+		// End of input reached. This is the only case where
+		// that is not an error but a signal that we are done.
+		p.err = nil
+		return nil
+	}
+	switch p.currentByte {
+	case '#':
+		return p.startComment
+	case '\n':
+		return p.startOfLine // Empty line, start the next one.
+	}
+	return p.readingMetricName
+}
+
+// startComment represents the state where the next byte read from p.buf is the
+// start of a comment (or whitespace leading up to it).
+func (p *TextParser) startComment() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	// If we have hit the end of line already, there is nothing left
+	// to do. This is not considered a syntax error.
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	keyword := p.currentToken.String()
+	if keyword != "HELP" && keyword != "TYPE" {
+		// Generic comment, ignore by fast forwarding to end of line.
+		for p.currentByte != '\n' {
+			if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+				return nil // Unexpected end of input.
+			}
+		}
+		return p.startOfLine
+	}
+	// There is something. Next has to be a metric name.
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	if !isBlankOrTab(p.currentByte) {
+		p.parseError("invalid metric name in comment")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	switch keyword {
+	case "HELP":
+		return p.readingHelp
+	case "TYPE":
+		return p.readingType
+	}
+	panic(fmt.Sprintf("code error: unexpected keyword %q", keyword))
+}
+
+// readingMetricName represents the state where the last byte read (now in
+// p.currentByte) is the first byte of a metric name.
+func (p *TextParser) readingMetricName() stateFn {
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError("invalid metric name")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	// Now is the time to fix the type if it hasn't happened yet.
+	if p.currentMF.Type == nil {
+		p.currentMF.Type = dto.MetricType_UNTYPED.Enum()
+	}
+	p.currentMetric = &dto.Metric{}
+	// Do not append the newly created currentMetric to
+	// currentMF.Metric right now. First wait if this is a summary,
+	// and the metric exists already, which we can only know after
+	// having read all the labels.
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	return p.readingLabels
+}
+
+// readingLabels represents the state where the last byte read (now in
+// p.currentByte) is either the first byte of the label set (i.e. a '{'), or the
+// first byte of the value (otherwise).
+func (p *TextParser) readingLabels() stateFn {
+	// Summaries/histograms are special. We have to reset the
+	// currentLabels map, currentQuantile and currentBucket before starting to
+	// read labels.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY || p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		p.currentLabels = map[string]string{}
+		p.currentLabels[string(model.MetricNameLabel)] = p.currentMF.GetName()
+		p.currentQuantile = math.NaN()
+		p.currentBucket = math.NaN()
+	}
+	if p.currentByte != '{' {
+		return p.readingValue
+	}
+	return p.startLabelName
+}
+
+// startLabelName represents the state where the next byte read from p.buf is
+// the start of a label name (or whitespace leading up to it).
+func (p *TextParser) startLabelName() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '}' {
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	}
+	if p.readTokenAsLabelName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError(fmt.Sprintf("invalid label name for metric %q", p.currentMF.GetName()))
+		return nil
+	}
+	p.currentLabelPair = &dto.LabelPair{Name: proto.String(p.currentToken.String())}
+	if p.currentLabelPair.GetName() == string(model.MetricNameLabel) {
+		p.parseError(fmt.Sprintf("label name %q is reserved", model.MetricNameLabel))
+		return nil
+	}
+	// Special summary/histogram treatment. Don't add 'quantile' and 'le'
+	// labels to 'real' labels.
+	if !(p.currentMF.GetType() == dto.MetricType_SUMMARY && p.currentLabelPair.GetName() == model.QuantileLabel) &&
+		!(p.currentMF.GetType() == dto.MetricType_HISTOGRAM && p.currentLabelPair.GetName() == model.BucketLabel) {
+		p.currentMetric.Label = append(p.currentMetric.Label, p.currentLabelPair)
+	}
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '=' {
+		p.parseError(fmt.Sprintf("expected '=' after label name, found %q", p.currentByte))
+		return nil
+	}
+	return p.startLabelValue
+}
+
+// startLabelValue represents the state where the next byte read from p.buf is
+// the start of a (quoted) label value (or whitespace leading up to it).
+func (p *TextParser) startLabelValue() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '"' {
+		p.parseError(fmt.Sprintf("expected '\"' at start of label value, found %q", p.currentByte))
+		return nil
+	}
+	if p.readTokenAsLabelValue(); p.err != nil {
+		return nil
+	}
+	if !model.LabelValue(p.currentToken.String()).IsValid() {
+		p.parseError(fmt.Sprintf("invalid label value %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentLabelPair.Value = proto.String(p.currentToken.String())
+	// Special treatment of summaries:
+	// - Quantile labels are special, will result in dto.Quantile later.
+	// - Other labels have to be added to currentLabels for signature calculation.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		if p.currentLabelPair.GetName() == model.QuantileLabel {
+			if p.currentQuantile, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'quantile' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	// Similar special treatment of histograms.
+	if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		if p.currentLabelPair.GetName() == model.BucketLabel {
+			if p.currentBucket, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'le' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	switch p.currentByte {
+	case ',':
+		return p.startLabelName
+
+	case '}':
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	default:
+		p.parseError(fmt.Sprintf("unexpected end of label value %q", p.currentLabelPair.GetValue()))
+		return nil
+	}
+}
+
+// readingValue represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the sample value (i.e. a float).
+func (p *TextParser) readingValue() stateFn {
+	// When we are here, we have read all the labels, so for the
+	// special case of a summary/histogram, we can finally find out
+	// if the metric already exists.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if summary := p.summaries[signature]; summary != nil {
+			p.currentMetric = summary
+		} else {
+			p.summaries[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if histogram := p.histograms[signature]; histogram != nil {
+			p.currentMetric = histogram
+		} else {
+			p.histograms[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else {
+		p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	value, err := strconv.ParseFloat(p.currentToken.String(), 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected float as value, got %q", p.currentToken.String()))
+		return nil
+	}
+	switch p.currentMF.GetType() {
+	case dto.MetricType_COUNTER:
+		p.currentMetric.Counter = &dto.Counter{Value: proto.Float64(value)}
+	case dto.MetricType_GAUGE:
+		p.currentMetric.Gauge = &dto.Gauge{Value: proto.Float64(value)}
+	case dto.MetricType_UNTYPED:
+		p.currentMetric.Untyped = &dto.Untyped{Value: proto.Float64(value)}
+	case dto.MetricType_SUMMARY:
+		// *sigh*
+		if p.currentMetric.Summary == nil {
+			p.currentMetric.Summary = &dto.Summary{}
+		}
+		switch {
+		case p.currentIsSummaryCount:
+			p.currentMetric.Summary.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsSummarySum:
+			p.currentMetric.Summary.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentQuantile):
+			p.currentMetric.Summary.Quantile = append(
+				p.currentMetric.Summary.Quantile,
+				&dto.Quantile{
+					Quantile: proto.Float64(p.currentQuantile),
+					Value:    proto.Float64(value),
+				},
+			)
+		}
+	case dto.MetricType_HISTOGRAM:
+		// *sigh*
+		if p.currentMetric.Histogram == nil {
+			p.currentMetric.Histogram = &dto.Histogram{}
+		}
+		switch {
+		case p.currentIsHistogramCount:
+			p.currentMetric.Histogram.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsHistogramSum:
+			p.currentMetric.Histogram.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentBucket):
+			p.currentMetric.Histogram.Bucket = append(
+				p.currentMetric.Histogram.Bucket,
+				&dto.Bucket{
+					UpperBound:      proto.Float64(p.currentBucket),
+					CumulativeCount: proto.Uint64(uint64(value)),
+				},
+			)
+		}
+	default:
+		p.err = fmt.Errorf("unexpected type for metric name %q", p.currentMF.GetName())
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	return p.startTimestamp
+}
+
+// startTimestamp represents the state where the next byte read from p.buf is
+// the start of the timestamp (or whitespace leading up to it).
+func (p *TextParser) startTimestamp() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	timestamp, err := strconv.ParseInt(p.currentToken.String(), 10, 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected integer as timestamp, got %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMetric.TimestampMs = proto.Int64(timestamp)
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() > 0 {
+		p.parseError(fmt.Sprintf("spurious string after timestamp: %q", p.currentToken.String()))
+		return nil
+	}
+	return p.startOfLine
+}
+
+// readingHelp represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the docstring after 'HELP'.
+func (p *TextParser) readingHelp() stateFn {
+	if p.currentMF.Help != nil {
+		p.parseError(fmt.Sprintf("second HELP line for metric name %q", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the docstring.
+	if p.readTokenUntilNewline(true); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	p.currentMF.Help = proto.String(p.currentToken.String())
+	return p.startOfLine
+}
+
+// readingType represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the type hint after 'HELP'.
+func (p *TextParser) readingType() stateFn {
+	if p.currentMF.Type != nil {
+		p.parseError(fmt.Sprintf("second TYPE line for metric name %q, or TYPE reported after samples", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the type.
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	metricType, ok := dto.MetricType_value[strings.ToUpper(p.currentToken.String())]
+	if !ok {
+		p.parseError(fmt.Sprintf("unknown metric type %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMF.Type = dto.MetricType(metricType).Enum()
+	return p.startOfLine
+}
+
+// parseError sets p.err to a ParseError at the current line with the given
+// message.
+func (p *TextParser) parseError(msg string) {
+	p.err = ParseError{
+		Line: p.lineCount,
+		Msg:  msg,
+	}
+}
+
+// skipBlankTab reads (and discards) bytes from p.buf until it encounters a byte
+// that is neither ' ' nor '\t'. That byte is left in p.currentByte.
+func (p *TextParser) skipBlankTab() {
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil || !isBlankOrTab(p.currentByte) {
+			return
+		}
+	}
+}
+
+// skipBlankTabIfCurrentBlankTab works exactly as skipBlankTab but doesn't do
+// anything if p.currentByte is neither ' ' nor '\t'.
+func (p *TextParser) skipBlankTabIfCurrentBlankTab() {
+	if isBlankOrTab(p.currentByte) {
+		p.skipBlankTab()
+	}
+}
+
+// readTokenUntilWhitespace copies bytes from p.buf into p.currentToken.  The
+// first byte considered is the byte already read (now in p.currentByte).  The
+// first whitespace byte encountered is still copied into p.currentByte, but not
+// into p.currentToken.
+func (p *TextParser) readTokenUntilWhitespace() {
+	p.currentToken.Reset()
+	for p.err == nil && !isBlankOrTab(p.currentByte) && p.currentByte != '\n' {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenUntilNewline copies bytes from p.buf into p.currentToken.  The first
+// byte considered is the byte already read (now in p.currentByte).  The first
+// newline byte encountered is still copied into p.currentByte, but not into
+// p.currentToken. If recognizeEscapeSequence is true, two escape sequences are
+// recognized: '\\' translates into '\', and '\n' into a line-feed character.
+// All other escape sequences are invalid and cause an error.
+func (p *TextParser) readTokenUntilNewline(recognizeEscapeSequence bool) {
+	p.currentToken.Reset()
+	escaped := false
+	for p.err == nil {
+		if recognizeEscapeSequence && escaped {
+			switch p.currentByte {
+			case '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+		} else {
+			switch p.currentByte {
+			case '\n':
+				return
+			case '\\':
+				escaped = true
+			default:
+				p.currentToken.WriteByte(p.currentByte)
+			}
+		}
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenAsMetricName copies a metric name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a metric name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsMetricName() {
+	p.currentToken.Reset()
+	if !isValidMetricNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidMetricNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelName copies a label name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a label name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelName() {
+	p.currentToken.Reset()
+	if !isValidLabelNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidLabelNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelValue copies a label value from p.buf into p.currentToken.
+// In contrast to the other 'readTokenAs...' functions, which start with the
+// last read byte in p.currentByte, this method ignores p.currentByte and starts
+// with reading a new byte from p.buf. The first byte not part of a label value
+// is still copied into p.currentByte, but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelValue() {
+	p.currentToken.Reset()
+	escaped := false
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+			return
+		}
+		if escaped {
+			switch p.currentByte {
+			case '"', '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+			continue
+		}
+		switch p.currentByte {
+		case '"':
+			return
+		case '\n':
+			p.parseError(fmt.Sprintf("label value %q contains unescaped new-line", p.currentToken.String()))
+			return
+		case '\\':
+			escaped = true
+		default:
+			p.currentToken.WriteByte(p.currentByte)
+		}
+	}
+}
+
+func (p *TextParser) setOrCreateCurrentMF() {
+	p.currentIsSummaryCount = false
+	p.currentIsSummarySum = false
+	p.currentIsHistogramCount = false
+	p.currentIsHistogramSum = false
+	name := p.currentToken.String()
+	if p.currentMF = p.metricFamiliesByName[name]; p.currentMF != nil {
+		return
+	}
+	// Try out if this is a _sum or _count for a summary/histogram.
+	summaryName := summaryMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[summaryName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+			if isCount(name) {
+				p.currentIsSummaryCount = true
+			}
+			if isSum(name) {
+				p.currentIsSummarySum = true
+			}
+			return
+		}
+	}
+	histogramName := histogramMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[histogramName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+			if isCount(name) {
+				p.currentIsHistogramCount = true
+			}
+			if isSum(name) {
+				p.currentIsHistogramSum = true
+			}
+			return
+		}
+	}
+	p.currentMF = &dto.MetricFamily{Name: proto.String(name)}
+	p.metricFamiliesByName[name] = p.currentMF
+}
+
+func isValidLabelNameStart(b byte) bool {
+	return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_'
+}
+
+func isValidLabelNameContinuation(b byte) bool {
+	return isValidLabelNameStart(b) || (b >= '0' && b <= '9')
+}
+
+func isValidMetricNameStart(b byte) bool {
+	return isValidLabelNameStart(b) || b == ':'
+}
+
+func isValidMetricNameContinuation(b byte) bool {
+	return isValidLabelNameContinuation(b) || b == ':'
+}
+
+func isBlankOrTab(b byte) bool {
+	return b == ' ' || b == '\t'
+}
+
+func isCount(name string) bool {
+	return len(name) > 6 && name[len(name)-6:] == "_count"
+}
+
+func isSum(name string) bool {
+	return len(name) > 4 && name[len(name)-4:] == "_sum"
+}
+
+func isBucket(name string) bool {
+	return len(name) > 7 && name[len(name)-7:] == "_bucket"
+}
+
+func summaryMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	default:
+		return name
+	}
+}
+
+func histogramMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	case isBucket(name):
+		return name[:len(name)-7]
+	default:
+		return name
+	}
+}
diff --git a/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/README.txt b/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/README.txt
new file mode 100644
index 0000000000..7723656d58
--- /dev/null
+++ b/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/README.txt
@@ -0,0 +1,67 @@
+PACKAGE
+
+package goautoneg
+import "bitbucket.org/ww/goautoneg"
+
+HTTP Content-Type Autonegotiation.
+
+The functions in this package implement the behaviour specified in
+http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+
+Copyright (c) 2011, Open Knowledge Foundation Ltd.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    Neither the name of the Open Knowledge Foundation Ltd. nor the
+    names of its contributors may be used to endorse or promote
+    products derived from this software without specific prior written
+    permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+FUNCTIONS
+
+func Negotiate(header string, alternatives []string) (content_type string)
+Negotiate the most appropriate content_type given the accept header
+and a list of alternatives.
+
+func ParseAccept(header string) (accept []Accept)
+Parse an Accept Header string returning a sorted list
+of clauses
+
+
+TYPES
+
+type Accept struct {
+    Type, SubType string
+    Q             float32
+    Params        map[string]string
+}
+Structure to represent a clause in an HTTP Accept Header
+
+
+SUBDIRECTORIES
+
+	.hg
diff --git a/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/autoneg.go b/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/autoneg.go
new file mode 100644
index 0000000000..26e92288c7
--- /dev/null
+++ b/vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/autoneg.go
@@ -0,0 +1,162 @@
+/*
+Copyright (c) 2011, Open Knowledge Foundation Ltd.
+All rights reserved.
+
+HTTP Content-Type Autonegotiation.
+
+The functions in this package implement the behaviour specified in
+http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    Neither the name of the Open Knowledge Foundation Ltd. nor the
+    names of its contributors may be used to endorse or promote
+    products derived from this software without specific prior written
+    permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+*/
+package goautoneg
+
+import (
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// Structure to represent a clause in an HTTP Accept Header
+type Accept struct {
+	Type, SubType string
+	Q             float64
+	Params        map[string]string
+}
+
+// For internal use, so that we can use the sort interface
+type accept_slice []Accept
+
+func (accept accept_slice) Len() int {
+	slice := []Accept(accept)
+	return len(slice)
+}
+
+func (accept accept_slice) Less(i, j int) bool {
+	slice := []Accept(accept)
+	ai, aj := slice[i], slice[j]
+	if ai.Q > aj.Q {
+		return true
+	}
+	if ai.Type != "*" && aj.Type == "*" {
+		return true
+	}
+	if ai.SubType != "*" && aj.SubType == "*" {
+		return true
+	}
+	return false
+}
+
+func (accept accept_slice) Swap(i, j int) {
+	slice := []Accept(accept)
+	slice[i], slice[j] = slice[j], slice[i]
+}
+
+// Parse an Accept Header string returning a sorted list
+// of clauses
+func ParseAccept(header string) (accept []Accept) {
+	parts := strings.Split(header, ",")
+	accept = make([]Accept, 0, len(parts))
+	for _, part := range parts {
+		part := strings.Trim(part, " ")
+
+		a := Accept{}
+		a.Params = make(map[string]string)
+		a.Q = 1.0
+
+		mrp := strings.Split(part, ";")
+
+		media_range := mrp[0]
+		sp := strings.Split(media_range, "/")
+		a.Type = strings.Trim(sp[0], " ")
+
+		switch {
+		case len(sp) == 1 && a.Type == "*":
+			a.SubType = "*"
+		case len(sp) == 2:
+			a.SubType = strings.Trim(sp[1], " ")
+		default:
+			continue
+		}
+
+		if len(mrp) == 1 {
+			accept = append(accept, a)
+			continue
+		}
+
+		for _, param := range mrp[1:] {
+			sp := strings.SplitN(param, "=", 2)
+			if len(sp) != 2 {
+				continue
+			}
+			token := strings.Trim(sp[0], " ")
+			if token == "q" {
+				a.Q, _ = strconv.ParseFloat(sp[1], 32)
+			} else {
+				a.Params[token] = strings.Trim(sp[1], " ")
+			}
+		}
+
+		accept = append(accept, a)
+	}
+
+	slice := accept_slice(accept)
+	sort.Sort(slice)
+
+	return
+}
+
+// Negotiate the most appropriate content_type given the accept header
+// and a list of alternatives.
+func Negotiate(header string, alternatives []string) (content_type string) {
+	asp := make([][]string, 0, len(alternatives))
+	for _, ctype := range alternatives {
+		asp = append(asp, strings.SplitN(ctype, "/", 2))
+	}
+	for _, clause := range ParseAccept(header) {
+		for i, ctsp := range asp {
+			if clause.Type == ctsp[0] && clause.SubType == ctsp[1] {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == ctsp[0] && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == "*" && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+		}
+	}
+	return
+}
diff --git a/vendor/github.com/prometheus/common/model/alert.go b/vendor/github.com/prometheus/common/model/alert.go
new file mode 100644
index 0000000000..35e739c7ad
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/alert.go
@@ -0,0 +1,136 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"time"
+)
+
+type AlertStatus string
+
+const (
+	AlertFiring   AlertStatus = "firing"
+	AlertResolved AlertStatus = "resolved"
+)
+
+// Alert is a generic representation of an alert in the Prometheus eco-system.
+type Alert struct {
+	// Label value pairs for purpose of aggregation, matching, and disposition
+	// dispatching. This must minimally include an "alertname" label.
+	Labels LabelSet `json:"labels"`
+
+	// Extra key/value information which does not define alert identity.
+	Annotations LabelSet `json:"annotations"`
+
+	// The known time range for this alert. Both ends are optional.
+	StartsAt     time.Time `json:"startsAt,omitempty"`
+	EndsAt       time.Time `json:"endsAt,omitempty"`
+	GeneratorURL string    `json:"generatorURL"`
+}
+
+// Name returns the name of the alert. It is equivalent to the "alertname" label.
+func (a *Alert) Name() string {
+	return string(a.Labels[AlertNameLabel])
+}
+
+// Fingerprint returns a unique hash for the alert. It is equivalent to
+// the fingerprint of the alert's label set.
+func (a *Alert) Fingerprint() Fingerprint {
+	return a.Labels.Fingerprint()
+}
+
+func (a *Alert) String() string {
+	s := fmt.Sprintf("%s[%s]", a.Name(), a.Fingerprint().String()[:7])
+	if a.Resolved() {
+		return s + "[resolved]"
+	}
+	return s + "[active]"
+}
+
+// Resolved returns true iff the activity interval ended in the past.
+func (a *Alert) Resolved() bool {
+	return a.ResolvedAt(time.Now())
+}
+
+// ResolvedAt returns true off the activity interval ended before
+// the given timestamp.
+func (a *Alert) ResolvedAt(ts time.Time) bool {
+	if a.EndsAt.IsZero() {
+		return false
+	}
+	return !a.EndsAt.After(ts)
+}
+
+// Status returns the status of the alert.
+func (a *Alert) Status() AlertStatus {
+	if a.Resolved() {
+		return AlertResolved
+	}
+	return AlertFiring
+}
+
+// Validate checks whether the alert data is inconsistent.
+func (a *Alert) Validate() error {
+	if a.StartsAt.IsZero() {
+		return fmt.Errorf("start time missing")
+	}
+	if !a.EndsAt.IsZero() && a.EndsAt.Before(a.StartsAt) {
+		return fmt.Errorf("start time must be before end time")
+	}
+	if err := a.Labels.Validate(); err != nil {
+		return fmt.Errorf("invalid label set: %s", err)
+	}
+	if len(a.Labels) == 0 {
+		return fmt.Errorf("at least one label pair required")
+	}
+	if err := a.Annotations.Validate(); err != nil {
+		return fmt.Errorf("invalid annotations: %s", err)
+	}
+	return nil
+}
+
+// Alert is a list of alerts that can be sorted in chronological order.
+type Alerts []*Alert
+
+func (as Alerts) Len() int      { return len(as) }
+func (as Alerts) Swap(i, j int) { as[i], as[j] = as[j], as[i] }
+
+func (as Alerts) Less(i, j int) bool {
+	if as[i].StartsAt.Before(as[j].StartsAt) {
+		return true
+	}
+	if as[i].EndsAt.Before(as[j].EndsAt) {
+		return true
+	}
+	return as[i].Fingerprint() < as[j].Fingerprint()
+}
+
+// HasFiring returns true iff one of the alerts is not resolved.
+func (as Alerts) HasFiring() bool {
+	for _, a := range as {
+		if !a.Resolved() {
+			return true
+		}
+	}
+	return false
+}
+
+// Status returns StatusFiring iff at least one of the alerts is firing.
+func (as Alerts) Status() AlertStatus {
+	if as.HasFiring() {
+		return AlertFiring
+	}
+	return AlertResolved
+}
diff --git a/vendor/github.com/prometheus/common/model/fingerprinting.go b/vendor/github.com/prometheus/common/model/fingerprinting.go
new file mode 100644
index 0000000000..fc4de4106e
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/fingerprinting.go
@@ -0,0 +1,105 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// Fingerprint provides a hash-capable representation of a Metric.
+// For our purposes, FNV-1A 64-bit is used.
+type Fingerprint uint64
+
+// FingerprintFromString transforms a string representation into a Fingerprint.
+func FingerprintFromString(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	return Fingerprint(num), err
+}
+
+// ParseFingerprint parses the input string into a fingerprint.
+func ParseFingerprint(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return 0, err
+	}
+	return Fingerprint(num), nil
+}
+
+func (f Fingerprint) String() string {
+	return fmt.Sprintf("%016x", uint64(f))
+}
+
+// Fingerprints represents a collection of Fingerprint subject to a given
+// natural sorting scheme. It implements sort.Interface.
+type Fingerprints []Fingerprint
+
+// Len implements sort.Interface.
+func (f Fingerprints) Len() int {
+	return len(f)
+}
+
+// Less implements sort.Interface.
+func (f Fingerprints) Less(i, j int) bool {
+	return f[i] < f[j]
+}
+
+// Swap implements sort.Interface.
+func (f Fingerprints) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
+// FingerprintSet is a set of Fingerprints.
+type FingerprintSet map[Fingerprint]struct{}
+
+// Equal returns true if both sets contain the same elements (and not more).
+func (s FingerprintSet) Equal(o FingerprintSet) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for k := range s {
+		if _, ok := o[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Intersection returns the elements contained in both sets.
+func (s FingerprintSet) Intersection(o FingerprintSet) FingerprintSet {
+	myLength, otherLength := len(s), len(o)
+	if myLength == 0 || otherLength == 0 {
+		return FingerprintSet{}
+	}
+
+	subSet := s
+	superSet := o
+
+	if otherLength < myLength {
+		subSet = o
+		superSet = s
+	}
+
+	out := FingerprintSet{}
+
+	for k := range subSet {
+		if _, ok := superSet[k]; ok {
+			out[k] = struct{}{}
+		}
+	}
+
+	return out
+}
diff --git a/vendor/github.com/prometheus/common/model/fnv.go b/vendor/github.com/prometheus/common/model/fnv.go
new file mode 100644
index 0000000000..038fc1c900
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/fnv.go
@@ -0,0 +1,42 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+// Inline and byte-free variant of hash/fnv's fnv64a.
+
+const (
+	offset64 = 14695981039346656037
+	prime64  = 1099511628211
+)
+
+// hashNew initializies a new fnv64a hash value.
+func hashNew() uint64 {
+	return offset64
+}
+
+// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
+func hashAdd(h uint64, s string) uint64 {
+	for i := 0; i < len(s); i++ {
+		h ^= uint64(s[i])
+		h *= prime64
+	}
+	return h
+}
+
+// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
+func hashAddByte(h uint64, b byte) uint64 {
+	h ^= uint64(b)
+	h *= prime64
+	return h
+}
diff --git a/vendor/github.com/prometheus/common/model/labels.go b/vendor/github.com/prometheus/common/model/labels.go
new file mode 100644
index 0000000000..41051a01a3
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/labels.go
@@ -0,0 +1,210 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strings"
+	"unicode/utf8"
+)
+
+const (
+	// AlertNameLabel is the name of the label containing the an alert's name.
+	AlertNameLabel = "alertname"
+
+	// ExportedLabelPrefix is the prefix to prepend to the label names present in
+	// exported metrics if a label of the same name is added by the server.
+	ExportedLabelPrefix = "exported_"
+
+	// MetricNameLabel is the label name indicating the metric name of a
+	// timeseries.
+	MetricNameLabel = "__name__"
+
+	// SchemeLabel is the name of the label that holds the scheme on which to
+	// scrape a target.
+	SchemeLabel = "__scheme__"
+
+	// AddressLabel is the name of the label that holds the address of
+	// a scrape target.
+	AddressLabel = "__address__"
+
+	// MetricsPathLabel is the name of the label that holds the path on which to
+	// scrape a target.
+	MetricsPathLabel = "__metrics_path__"
+
+	// ReservedLabelPrefix is a prefix which is not legal in user-supplied
+	// label names.
+	ReservedLabelPrefix = "__"
+
+	// MetaLabelPrefix is a prefix for labels that provide meta information.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series.
+	MetaLabelPrefix = "__meta_"
+
+	// TmpLabelPrefix is a prefix for temporary labels as part of relabelling.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series. This is reserved for use in
+	// Prometheus configuration files by users.
+	TmpLabelPrefix = "__tmp_"
+
+	// ParamLabelPrefix is a prefix for labels that provide URL parameters
+	// used to scrape a target.
+	ParamLabelPrefix = "__param_"
+
+	// JobLabel is the label name indicating the job from which a timeseries
+	// was scraped.
+	JobLabel = "job"
+
+	// InstanceLabel is the label name used for the instance label.
+	InstanceLabel = "instance"
+
+	// BucketLabel is used for the label that defines the upper bound of a
+	// bucket of a histogram ("le" -> "less or equal").
+	BucketLabel = "le"
+
+	// QuantileLabel is used for the label that defines the quantile in a
+	// summary.
+	QuantileLabel = "quantile"
+)
+
+// LabelNameRE is a regular expression matching valid label names. Note that the
+// IsValid method of LabelName performs the same check but faster than a match
+// with this regular expression.
+var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+
+// A LabelName is a key for a LabelSet or Metric.  It has a value associated
+// therewith.
+type LabelName string
+
+// IsValid is true iff the label name matches the pattern of LabelNameRE. This
+// method, however, does not use LabelNameRE for the check but a much faster
+// hardcoded implementation.
+func (ln LabelName) IsValid() bool {
+	if len(ln) == 0 {
+		return false
+	}
+	for i, b := range ln {
+		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || (b >= '0' && b <= '9' && i > 0)) {
+			return false
+		}
+	}
+	return true
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	if !LabelName(s).IsValid() {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (ln *LabelName) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	if !LabelName(s).IsValid() {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// LabelNames is a sortable LabelName slice. In implements sort.Interface.
+type LabelNames []LabelName
+
+func (l LabelNames) Len() int {
+	return len(l)
+}
+
+func (l LabelNames) Less(i, j int) bool {
+	return l[i] < l[j]
+}
+
+func (l LabelNames) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+func (l LabelNames) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for _, label := range l {
+		labelStrings = append(labelStrings, string(label))
+	}
+	return strings.Join(labelStrings, ", ")
+}
+
+// A LabelValue is an associated value for a LabelName.
+type LabelValue string
+
+// IsValid returns true iff the string is a valid UTF8.
+func (lv LabelValue) IsValid() bool {
+	return utf8.ValidString(string(lv))
+}
+
+// LabelValues is a sortable LabelValue slice. It implements sort.Interface.
+type LabelValues []LabelValue
+
+func (l LabelValues) Len() int {
+	return len(l)
+}
+
+func (l LabelValues) Less(i, j int) bool {
+	return string(l[i]) < string(l[j])
+}
+
+func (l LabelValues) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+// LabelPair pairs a name with a value.
+type LabelPair struct {
+	Name  LabelName
+	Value LabelValue
+}
+
+// LabelPairs is a sortable slice of LabelPair pointers. It implements
+// sort.Interface.
+type LabelPairs []*LabelPair
+
+func (l LabelPairs) Len() int {
+	return len(l)
+}
+
+func (l LabelPairs) Less(i, j int) bool {
+	switch {
+	case l[i].Name > l[j].Name:
+		return false
+	case l[i].Name < l[j].Name:
+		return true
+	case l[i].Value > l[j].Value:
+		return false
+	case l[i].Value < l[j].Value:
+		return true
+	default:
+		return false
+	}
+}
+
+func (l LabelPairs) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
diff --git a/vendor/github.com/prometheus/common/model/labelset.go b/vendor/github.com/prometheus/common/model/labelset.go
new file mode 100644
index 0000000000..6eda08a739
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/labelset.go
@@ -0,0 +1,169 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A LabelSet is a collection of LabelName and LabelValue pairs.  The LabelSet
+// may be fully-qualified down to the point where it may resolve to a single
+// Metric in the data store or not.  All operations that occur within the realm
+// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
+// match.
+type LabelSet map[LabelName]LabelValue
+
+// Validate checks whether all names and values in the label set
+// are valid.
+func (ls LabelSet) Validate() error {
+	for ln, lv := range ls {
+		if !ln.IsValid() {
+			return fmt.Errorf("invalid name %q", ln)
+		}
+		if !lv.IsValid() {
+			return fmt.Errorf("invalid value %q", lv)
+		}
+	}
+	return nil
+}
+
+// Equal returns true iff both label sets have exactly the same key/value pairs.
+func (ls LabelSet) Equal(o LabelSet) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for ln, lv := range ls {
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if olv != lv {
+			return false
+		}
+	}
+	return true
+}
+
+// Before compares the metrics, using the following criteria:
+//
+// If m has fewer labels than o, it is before o. If it has more, it is not.
+//
+// If the number of labels is the same, the superset of all label names is
+// sorted alphanumerically. The first differing label pair found in that order
+// determines the outcome: If the label does not exist at all in m, then m is
+// before o, and vice versa. Otherwise the label value is compared
+// alphanumerically.
+//
+// If m and o are equal, the method returns false.
+func (ls LabelSet) Before(o LabelSet) bool {
+	if len(ls) < len(o) {
+		return true
+	}
+	if len(ls) > len(o) {
+		return false
+	}
+
+	lns := make(LabelNames, 0, len(ls)+len(o))
+	for ln := range ls {
+		lns = append(lns, ln)
+	}
+	for ln := range o {
+		lns = append(lns, ln)
+	}
+	// It's probably not worth it to de-dup lns.
+	sort.Sort(lns)
+	for _, ln := range lns {
+		mlv, ok := ls[ln]
+		if !ok {
+			return true
+		}
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if mlv < olv {
+			return true
+		}
+		if mlv > olv {
+			return false
+		}
+	}
+	return false
+}
+
+// Clone returns a copy of the label set.
+func (ls LabelSet) Clone() LabelSet {
+	lsn := make(LabelSet, len(ls))
+	for ln, lv := range ls {
+		lsn[ln] = lv
+	}
+	return lsn
+}
+
+// Merge is a helper function to non-destructively merge two label sets.
+func (l LabelSet) Merge(other LabelSet) LabelSet {
+	result := make(LabelSet, len(l))
+
+	for k, v := range l {
+		result[k] = v
+	}
+
+	for k, v := range other {
+		result[k] = v
+	}
+
+	return result
+}
+
+func (l LabelSet) String() string {
+	lstrs := make([]string, 0, len(l))
+	for l, v := range l {
+		lstrs = append(lstrs, fmt.Sprintf("%s=%q", l, v))
+	}
+
+	sort.Strings(lstrs)
+	return fmt.Sprintf("{%s}", strings.Join(lstrs, ", "))
+}
+
+// Fingerprint returns the LabelSet's fingerprint.
+func (ls LabelSet) Fingerprint() Fingerprint {
+	return labelSetToFingerprint(ls)
+}
+
+// FastFingerprint returns the LabelSet's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (ls LabelSet) FastFingerprint() Fingerprint {
+	return labelSetToFastFingerprint(ls)
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (l *LabelSet) UnmarshalJSON(b []byte) error {
+	var m map[LabelName]LabelValue
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+	// encoding/json only unmarshals maps of the form map[string]T. It treats
+	// LabelName as a string and does not call its UnmarshalJSON method.
+	// Thus, we have to replicate the behavior here.
+	for ln := range m {
+		if !ln.IsValid() {
+			return fmt.Errorf("%q is not a valid label name", ln)
+		}
+	}
+	*l = LabelSet(m)
+	return nil
+}
diff --git a/vendor/github.com/prometheus/common/model/metric.go b/vendor/github.com/prometheus/common/model/metric.go
new file mode 100644
index 0000000000..00804b7fed
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/metric.go
@@ -0,0 +1,102 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+)
+
+var (
+	// MetricNameRE is a regular expression matching valid metric
+	// names. Note that the IsValidMetricName function performs the same
+	// check but faster than a match with this regular expression.
+	MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
+)
+
+// A Metric is similar to a LabelSet, but the key difference is that a Metric is
+// a singleton and refers to one and only one stream of samples.
+type Metric LabelSet
+
+// Equal compares the metrics.
+func (m Metric) Equal(o Metric) bool {
+	return LabelSet(m).Equal(LabelSet(o))
+}
+
+// Before compares the metrics' underlying label sets.
+func (m Metric) Before(o Metric) bool {
+	return LabelSet(m).Before(LabelSet(o))
+}
+
+// Clone returns a copy of the Metric.
+func (m Metric) Clone() Metric {
+	clone := make(Metric, len(m))
+	for k, v := range m {
+		clone[k] = v
+	}
+	return clone
+}
+
+func (m Metric) String() string {
+	metricName, hasName := m[MetricNameLabel]
+	numLabels := len(m) - 1
+	if !hasName {
+		numLabels = len(m)
+	}
+	labelStrings := make([]string, 0, numLabels)
+	for label, value := range m {
+		if label != MetricNameLabel {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+		}
+	}
+
+	switch numLabels {
+	case 0:
+		if hasName {
+			return string(metricName)
+		}
+		return "{}"
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
+	}
+}
+
+// Fingerprint returns a Metric's Fingerprint.
+func (m Metric) Fingerprint() Fingerprint {
+	return LabelSet(m).Fingerprint()
+}
+
+// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (m Metric) FastFingerprint() Fingerprint {
+	return LabelSet(m).FastFingerprint()
+}
+
+// IsValidMetricName returns true iff name matches the pattern of MetricNameRE.
+// This function, however, does not use MetricNameRE for the check but a much
+// faster hardcoded implementation.
+func IsValidMetricName(n LabelValue) bool {
+	if len(n) == 0 {
+		return false
+	}
+	for i, b := range n {
+		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)) {
+			return false
+		}
+	}
+	return true
+}
diff --git a/vendor/github.com/prometheus/common/model/model.go b/vendor/github.com/prometheus/common/model/model.go
new file mode 100644
index 0000000000..a7b9691707
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/model.go
@@ -0,0 +1,16 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package model contains common data structures that are shared across
+// Prometheus components and libraries.
+package model
diff --git a/vendor/github.com/prometheus/common/model/signature.go b/vendor/github.com/prometheus/common/model/signature.go
new file mode 100644
index 0000000000..8762b13c63
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/signature.go
@@ -0,0 +1,144 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"sort"
+)
+
+// SeparatorByte is a byte that cannot occur in valid UTF-8 sequences and is
+// used to separate label names, label values, and other strings from each other
+// when calculating their combined hash value (aka signature aka fingerprint).
+const SeparatorByte byte = 255
+
+var (
+	// cache the signature of an empty label set.
+	emptyLabelSignature = hashNew()
+)
+
+// LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
+// given label set. (Collisions are possible but unlikely if the number of label
+// sets the function is applied to is small.)
+func LabelsToSignature(labels map[string]string) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make([]string, 0, len(labels))
+	for labelName := range labels {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Strings(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, labelName)
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, labels[labelName])
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}
+
+// labelSetToFingerprint works exactly as LabelsToSignature but takes a LabelSet as
+// parameter (rather than a label map) and returns a Fingerprint.
+func labelSetToFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	labelNames := make(LabelNames, 0, len(ls))
+	for labelName := range ls {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Sort(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(ls[labelName]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return Fingerprint(sum)
+}
+
+// labelSetToFastFingerprint works similar to labelSetToFingerprint but uses a
+// faster and less allocation-heavy hash function, which is more susceptible to
+// create hash collisions. Therefore, collision detection should be applied.
+func labelSetToFastFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	var result uint64
+	for labelName, labelValue := range ls {
+		sum := hashNew()
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(labelValue))
+		result ^= sum
+	}
+	return Fingerprint(result)
+}
+
+// SignatureForLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and only includes the labels with the
+// specified LabelNames into the signature calculation. The labels passed in
+// will be sorted by this function.
+func SignatureForLabels(m Metric, labels ...LabelName) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	sort.Sort(LabelNames(labels))
+
+	sum := hashNew()
+	for _, label := range labels {
+		sum = hashAdd(sum, string(label))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(m[label]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}
+
+// SignatureWithoutLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and excludes the labels with any of the
+// specified LabelNames from the signature calculation.
+func SignatureWithoutLabels(m Metric, labels map[LabelName]struct{}) uint64 {
+	if len(m) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		if _, exclude := labels[labelName]; !exclude {
+			labelNames = append(labelNames, labelName)
+		}
+	}
+	if len(labelNames) == 0 {
+		return emptyLabelSignature
+	}
+	sort.Sort(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(m[labelName]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}
diff --git a/vendor/github.com/prometheus/common/model/silence.go b/vendor/github.com/prometheus/common/model/silence.go
new file mode 100644
index 0000000000..bb99889d2c
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/silence.go
@@ -0,0 +1,106 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"time"
+)
+
+// Matcher describes a matches the value of a given label.
+type Matcher struct {
+	Name    LabelName `json:"name"`
+	Value   string    `json:"value"`
+	IsRegex bool      `json:"isRegex"`
+}
+
+func (m *Matcher) UnmarshalJSON(b []byte) error {
+	type plain Matcher
+	if err := json.Unmarshal(b, (*plain)(m)); err != nil {
+		return err
+	}
+
+	if len(m.Name) == 0 {
+		return fmt.Errorf("label name in matcher must not be empty")
+	}
+	if m.IsRegex {
+		if _, err := regexp.Compile(m.Value); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Validate returns true iff all fields of the matcher have valid values.
+func (m *Matcher) Validate() error {
+	if !m.Name.IsValid() {
+		return fmt.Errorf("invalid name %q", m.Name)
+	}
+	if m.IsRegex {
+		if _, err := regexp.Compile(m.Value); err != nil {
+			return fmt.Errorf("invalid regular expression %q", m.Value)
+		}
+	} else if !LabelValue(m.Value).IsValid() || len(m.Value) == 0 {
+		return fmt.Errorf("invalid value %q", m.Value)
+	}
+	return nil
+}
+
+// Silence defines the representation of a silence definition in the Prometheus
+// eco-system.
+type Silence struct {
+	ID uint64 `json:"id,omitempty"`
+
+	Matchers []*Matcher `json:"matchers"`
+
+	StartsAt time.Time `json:"startsAt"`
+	EndsAt   time.Time `json:"endsAt"`
+
+	CreatedAt time.Time `json:"createdAt,omitempty"`
+	CreatedBy string    `json:"createdBy"`
+	Comment   string    `json:"comment,omitempty"`
+}
+
+// Validate returns true iff all fields of the silence have valid values.
+func (s *Silence) Validate() error {
+	if len(s.Matchers) == 0 {
+		return fmt.Errorf("at least one matcher required")
+	}
+	for _, m := range s.Matchers {
+		if err := m.Validate(); err != nil {
+			return fmt.Errorf("invalid matcher: %s", err)
+		}
+	}
+	if s.StartsAt.IsZero() {
+		return fmt.Errorf("start time missing")
+	}
+	if s.EndsAt.IsZero() {
+		return fmt.Errorf("end time missing")
+	}
+	if s.EndsAt.Before(s.StartsAt) {
+		return fmt.Errorf("start time must be before end time")
+	}
+	if s.CreatedBy == "" {
+		return fmt.Errorf("creator information missing")
+	}
+	if s.Comment == "" {
+		return fmt.Errorf("comment missing")
+	}
+	if s.CreatedAt.IsZero() {
+		return fmt.Errorf("creation timestamp missing")
+	}
+	return nil
+}
diff --git a/vendor/github.com/prometheus/common/model/time.go b/vendor/github.com/prometheus/common/model/time.go
new file mode 100644
index 0000000000..46259b1f10
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/time.go
@@ -0,0 +1,264 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	// MinimumTick is the minimum supported time resolution. This has to be
+	// at least time.Second in order for the code below to work.
+	minimumTick = time.Millisecond
+	// second is the Time duration equivalent to one second.
+	second = int64(time.Second / minimumTick)
+	// The number of nanoseconds per minimum tick.
+	nanosPerTick = int64(minimumTick / time.Nanosecond)
+
+	// Earliest is the earliest Time representable. Handy for
+	// initializing a high watermark.
+	Earliest = Time(math.MinInt64)
+	// Latest is the latest Time representable. Handy for initializing
+	// a low watermark.
+	Latest = Time(math.MaxInt64)
+)
+
+// Time is the number of milliseconds since the epoch
+// (1970-01-01 00:00 UTC) excluding leap seconds.
+type Time int64
+
+// Interval describes an interval between two timestamps.
+type Interval struct {
+	Start, End Time
+}
+
+// Now returns the current time as a Time.
+func Now() Time {
+	return TimeFromUnixNano(time.Now().UnixNano())
+}
+
+// TimeFromUnix returns the Time equivalent to the Unix Time t
+// provided in seconds.
+func TimeFromUnix(t int64) Time {
+	return Time(t * second)
+}
+
+// TimeFromUnixNano returns the Time equivalent to the Unix Time
+// t provided in nanoseconds.
+func TimeFromUnixNano(t int64) Time {
+	return Time(t / nanosPerTick)
+}
+
+// Equal reports whether two Times represent the same instant.
+func (t Time) Equal(o Time) bool {
+	return t == o
+}
+
+// Before reports whether the Time t is before o.
+func (t Time) Before(o Time) bool {
+	return t < o
+}
+
+// After reports whether the Time t is after o.
+func (t Time) After(o Time) bool {
+	return t > o
+}
+
+// Add returns the Time t + d.
+func (t Time) Add(d time.Duration) Time {
+	return t + Time(d/minimumTick)
+}
+
+// Sub returns the Duration t - o.
+func (t Time) Sub(o Time) time.Duration {
+	return time.Duration(t-o) * minimumTick
+}
+
+// Time returns the time.Time representation of t.
+func (t Time) Time() time.Time {
+	return time.Unix(int64(t)/second, (int64(t)%second)*nanosPerTick)
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) Unix() int64 {
+	return int64(t) / second
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) UnixNano() int64 {
+	return int64(t) * nanosPerTick
+}
+
+// The number of digits after the dot.
+var dotPrecision = int(math.Log10(float64(second)))
+
+// String returns a string representation of the Time.
+func (t Time) String() string {
+	return strconv.FormatFloat(float64(t)/float64(second), 'f', -1, 64)
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (t Time) MarshalJSON() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (t *Time) UnmarshalJSON(b []byte) error {
+	p := strings.Split(string(b), ".")
+	switch len(p) {
+	case 1:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		*t = Time(v * second)
+
+	case 2:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		v *= second
+
+		prec := dotPrecision - len(p[1])
+		if prec < 0 {
+			p[1] = p[1][:dotPrecision]
+		} else if prec > 0 {
+			p[1] = p[1] + strings.Repeat("0", prec)
+		}
+
+		va, err := strconv.ParseInt(p[1], 10, 32)
+		if err != nil {
+			return err
+		}
+
+		*t = Time(v + va)
+
+	default:
+		return fmt.Errorf("invalid time %q", string(b))
+	}
+	return nil
+}
+
+// Duration wraps time.Duration. It is used to parse the custom duration format
+// from YAML.
+// This type should not propagate beyond the scope of input/output processing.
+type Duration time.Duration
+
+// Set implements pflag/flag.Value
+func (d *Duration) Set(s string) error {
+	var err error
+	*d, err = ParseDuration(s)
+	return err
+}
+
+// Type implements pflag.Value
+func (d *Duration) Type() string {
+	return "duration"
+}
+
+var durationRE = regexp.MustCompile("^([0-9]+)(y|w|d|h|m|s|ms)$")
+
+// ParseDuration parses a string into a time.Duration, assuming that a year
+// always has 365d, a week always has 7d, and a day always has 24h.
+func ParseDuration(durationStr string) (Duration, error) {
+	matches := durationRE.FindStringSubmatch(durationStr)
+	if len(matches) != 3 {
+		return 0, fmt.Errorf("not a valid duration string: %q", durationStr)
+	}
+	var (
+		n, _ = strconv.Atoi(matches[1])
+		dur  = time.Duration(n) * time.Millisecond
+	)
+	switch unit := matches[2]; unit {
+	case "y":
+		dur *= 1000 * 60 * 60 * 24 * 365
+	case "w":
+		dur *= 1000 * 60 * 60 * 24 * 7
+	case "d":
+		dur *= 1000 * 60 * 60 * 24
+	case "h":
+		dur *= 1000 * 60 * 60
+	case "m":
+		dur *= 1000 * 60
+	case "s":
+		dur *= 1000
+	case "ms":
+		// Value already correct
+	default:
+		return 0, fmt.Errorf("invalid time unit in duration string: %q", unit)
+	}
+	return Duration(dur), nil
+}
+
+func (d Duration) String() string {
+	var (
+		ms   = int64(time.Duration(d) / time.Millisecond)
+		unit = "ms"
+	)
+	if ms == 0 {
+		return "0s"
+	}
+	factors := map[string]int64{
+		"y":  1000 * 60 * 60 * 24 * 365,
+		"w":  1000 * 60 * 60 * 24 * 7,
+		"d":  1000 * 60 * 60 * 24,
+		"h":  1000 * 60 * 60,
+		"m":  1000 * 60,
+		"s":  1000,
+		"ms": 1,
+	}
+
+	switch int64(0) {
+	case ms % factors["y"]:
+		unit = "y"
+	case ms % factors["w"]:
+		unit = "w"
+	case ms % factors["d"]:
+		unit = "d"
+	case ms % factors["h"]:
+		unit = "h"
+	case ms % factors["m"]:
+		unit = "m"
+	case ms % factors["s"]:
+		unit = "s"
+	}
+	return fmt.Sprintf("%v%v", ms/factors[unit], unit)
+}
+
+// MarshalYAML implements the yaml.Marshaler interface.
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return d.String(), nil
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	dur, err := ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = dur
+	return nil
+}
diff --git a/vendor/github.com/prometheus/common/model/value.go b/vendor/github.com/prometheus/common/model/value.go
new file mode 100644
index 0000000000..c9d8fb1a28
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/value.go
@@ -0,0 +1,416 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"math"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+var (
+	// ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
+	// non-existing sample pair. It is a SamplePair with timestamp Earliest and
+	// value 0.0. Note that the natural zero value of SamplePair has a timestamp
+	// of 0, which is possible to appear in a real SamplePair and thus not
+	// suitable to signal a non-existing SamplePair.
+	ZeroSamplePair = SamplePair{Timestamp: Earliest}
+
+	// ZeroSample is the pseudo zero-value of Sample used to signal a
+	// non-existing sample. It is a Sample with timestamp Earliest, value 0.0,
+	// and metric nil. Note that the natural zero value of Sample has a timestamp
+	// of 0, which is possible to appear in a real Sample and thus not suitable
+	// to signal a non-existing Sample.
+	ZeroSample = Sample{Timestamp: Earliest}
+)
+
+// A SampleValue is a representation of a value for a given sample at a given
+// time.
+type SampleValue float64
+
+// MarshalJSON implements json.Marshaler.
+func (v SampleValue) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.String())
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (v *SampleValue) UnmarshalJSON(b []byte) error {
+	if len(b) < 2 || b[0] != '"' || b[len(b)-1] != '"' {
+		return fmt.Errorf("sample value must be a quoted string")
+	}
+	f, err := strconv.ParseFloat(string(b[1:len(b)-1]), 64)
+	if err != nil {
+		return err
+	}
+	*v = SampleValue(f)
+	return nil
+}
+
+// Equal returns true if the value of v and o is equal or if both are NaN. Note
+// that v==o is false if both are NaN. If you want the conventional float
+// behavior, use == to compare two SampleValues.
+func (v SampleValue) Equal(o SampleValue) bool {
+	if v == o {
+		return true
+	}
+	return math.IsNaN(float64(v)) && math.IsNaN(float64(o))
+}
+
+func (v SampleValue) String() string {
+	return strconv.FormatFloat(float64(v), 'f', -1, 64)
+}
+
+// SamplePair pairs a SampleValue with a Timestamp.
+type SamplePair struct {
+	Timestamp Time
+	Value     SampleValue
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s SamplePair) MarshalJSON() ([]byte, error) {
+	t, err := json.Marshal(s.Timestamp)
+	if err != nil {
+		return nil, err
+	}
+	v, err := json.Marshal(s.Value)
+	if err != nil {
+		return nil, err
+	}
+	return []byte(fmt.Sprintf("[%s,%s]", t, v)), nil
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *SamplePair) UnmarshalJSON(b []byte) error {
+	v := [...]json.Unmarshaler{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Equal returns true if this SamplePair and o have equal Values and equal
+// Timestamps. The semantics of Value equality is defined by SampleValue.Equal.
+func (s *SamplePair) Equal(o *SamplePair) bool {
+	return s == o || (s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp))
+}
+
+func (s SamplePair) String() string {
+	return fmt.Sprintf("%s @[%s]", s.Value, s.Timestamp)
+}
+
+// Sample is a sample pair associated with a metric.
+type Sample struct {
+	Metric    Metric      `json:"metric"`
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+// Equal compares first the metrics, then the timestamp, then the value. The
+// semantics of value equality is defined by SampleValue.Equal.
+func (s *Sample) Equal(o *Sample) bool {
+	if s == o {
+		return true
+	}
+
+	if !s.Metric.Equal(o.Metric) {
+		return false
+	}
+	if !s.Timestamp.Equal(o.Timestamp) {
+		return false
+	}
+
+	return s.Value.Equal(o.Value)
+}
+
+func (s Sample) String() string {
+	return fmt.Sprintf("%s => %s", s.Metric, SamplePair{
+		Timestamp: s.Timestamp,
+		Value:     s.Value,
+	})
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Sample) MarshalJSON() ([]byte, error) {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	return json.Marshal(&v)
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Sample) UnmarshalJSON(b []byte) error {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	s.Metric = v.Metric
+	s.Timestamp = v.Value.Timestamp
+	s.Value = v.Value.Value
+
+	return nil
+}
+
+// Samples is a sortable Sample slice. It implements sort.Interface.
+type Samples []*Sample
+
+func (s Samples) Len() int {
+	return len(s)
+}
+
+// Less compares first the metrics, then the timestamp.
+func (s Samples) Less(i, j int) bool {
+	switch {
+	case s[i].Metric.Before(s[j].Metric):
+		return true
+	case s[j].Metric.Before(s[i].Metric):
+		return false
+	case s[i].Timestamp.Before(s[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+func (s Samples) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (s Samples) Equal(o Samples) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for i, sample := range s {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// SampleStream is a stream of Values belonging to an attached COWMetric.
+type SampleStream struct {
+	Metric Metric       `json:"metric"`
+	Values []SamplePair `json:"values"`
+}
+
+func (ss SampleStream) String() string {
+	vals := make([]string, len(ss.Values))
+	for i, v := range ss.Values {
+		vals[i] = v.String()
+	}
+	return fmt.Sprintf("%s =>\n%s", ss.Metric, strings.Join(vals, "\n"))
+}
+
+// Value is a generic interface for values resulting from a query evaluation.
+type Value interface {
+	Type() ValueType
+	String() string
+}
+
+func (Matrix) Type() ValueType  { return ValMatrix }
+func (Vector) Type() ValueType  { return ValVector }
+func (*Scalar) Type() ValueType { return ValScalar }
+func (*String) Type() ValueType { return ValString }
+
+type ValueType int
+
+const (
+	ValNone ValueType = iota
+	ValScalar
+	ValVector
+	ValMatrix
+	ValString
+)
+
+// MarshalJSON implements json.Marshaler.
+func (et ValueType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(et.String())
+}
+
+func (et *ValueType) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	switch s {
+	case "<ValNone>":
+		*et = ValNone
+	case "scalar":
+		*et = ValScalar
+	case "vector":
+		*et = ValVector
+	case "matrix":
+		*et = ValMatrix
+	case "string":
+		*et = ValString
+	default:
+		return fmt.Errorf("unknown value type %q", s)
+	}
+	return nil
+}
+
+func (e ValueType) String() string {
+	switch e {
+	case ValNone:
+		return "<ValNone>"
+	case ValScalar:
+		return "scalar"
+	case ValVector:
+		return "vector"
+	case ValMatrix:
+		return "matrix"
+	case ValString:
+		return "string"
+	}
+	panic("ValueType.String: unhandled value type")
+}
+
+// Scalar is a scalar value evaluated at the set timestamp.
+type Scalar struct {
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+func (s Scalar) String() string {
+	return fmt.Sprintf("scalar: %v @[%v]", s.Value, s.Timestamp)
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Scalar) MarshalJSON() ([]byte, error) {
+	v := strconv.FormatFloat(float64(s.Value), 'f', -1, 64)
+	return json.Marshal([...]interface{}{s.Timestamp, string(v)})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Scalar) UnmarshalJSON(b []byte) error {
+	var f string
+	v := [...]interface{}{&s.Timestamp, &f}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	value, err := strconv.ParseFloat(f, 64)
+	if err != nil {
+		return fmt.Errorf("error parsing sample value: %s", err)
+	}
+	s.Value = SampleValue(value)
+	return nil
+}
+
+// String is a string value evaluated at the set timestamp.
+type String struct {
+	Value     string `json:"value"`
+	Timestamp Time   `json:"timestamp"`
+}
+
+func (s *String) String() string {
+	return s.Value
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s String) MarshalJSON() ([]byte, error) {
+	return json.Marshal([]interface{}{s.Timestamp, s.Value})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *String) UnmarshalJSON(b []byte) error {
+	v := [...]interface{}{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Vector is basically only an alias for Samples, but the
+// contract is that in a Vector, all Samples have the same timestamp.
+type Vector []*Sample
+
+func (vec Vector) String() string {
+	entries := make([]string, len(vec))
+	for i, s := range vec {
+		entries[i] = s.String()
+	}
+	return strings.Join(entries, "\n")
+}
+
+func (vec Vector) Len() int      { return len(vec) }
+func (vec Vector) Swap(i, j int) { vec[i], vec[j] = vec[j], vec[i] }
+
+// Less compares first the metrics, then the timestamp.
+func (vec Vector) Less(i, j int) bool {
+	switch {
+	case vec[i].Metric.Before(vec[j].Metric):
+		return true
+	case vec[j].Metric.Before(vec[i].Metric):
+		return false
+	case vec[i].Timestamp.Before(vec[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (vec Vector) Equal(o Vector) bool {
+	if len(vec) != len(o) {
+		return false
+	}
+
+	for i, sample := range vec {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// Matrix is a list of time series.
+type Matrix []*SampleStream
+
+func (m Matrix) Len() int           { return len(m) }
+func (m Matrix) Less(i, j int) bool { return m[i].Metric.Before(m[j].Metric) }
+func (m Matrix) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
+
+func (mat Matrix) String() string {
+	matCp := make(Matrix, len(mat))
+	copy(matCp, mat)
+	sort.Sort(matCp)
+
+	strs := make([]string, len(matCp))
+
+	for i, ss := range matCp {
+		strs[i] = ss.String()
+	}
+
+	return strings.Join(strs, "\n")
+}
diff --git a/vendor/github.com/prometheus/procfs/.gitignore b/vendor/github.com/prometheus/procfs/.gitignore
new file mode 100644
index 0000000000..25e3659ab2
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/.gitignore
@@ -0,0 +1 @@
+/fixtures/
diff --git a/vendor/github.com/prometheus/procfs/CONTRIBUTING.md b/vendor/github.com/prometheus/procfs/CONTRIBUTING.md
new file mode 100644
index 0000000000..40503edbf1
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/CONTRIBUTING.md
@@ -0,0 +1,18 @@
+# Contributing
+
+Prometheus uses GitHub to manage reviews of pull requests.
+
+* If you have a trivial fix or improvement, go ahead and create a pull request,
+  addressing (with `@...`) the maintainer of this repository (see
+  [MAINTAINERS.md](MAINTAINERS.md)) in the description of the pull request.
+
+* If you plan to do something more involved, first discuss your ideas
+  on our [mailing list](https://groups.google.com/forum/?fromgroups#!forum/prometheus-developers).
+  This will avoid unnecessary work and surely give you and us a good deal
+  of inspiration.
+
+* Relevant coding style guidelines are the [Go Code Review
+  Comments](https://code.google.com/p/go-wiki/wiki/CodeReviewComments)
+  and the _Formatting and style_ section of Peter Bourgon's [Go: Best
+  Practices for Production
+  Environments](http://peter.bourgon.org/go-in-production/#formatting-and-style).
diff --git a/vendor/github.com/prometheus/procfs/LICENSE b/vendor/github.com/prometheus/procfs/LICENSE
new file mode 100644
index 0000000000..261eeb9e9f
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
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+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
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+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
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+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
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+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
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+      (d) If the Work includes a "NOTICE" text file as part of its
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+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
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+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/prometheus/procfs/MAINTAINERS.md b/vendor/github.com/prometheus/procfs/MAINTAINERS.md
new file mode 100644
index 0000000000..f1d3b9937b
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/MAINTAINERS.md
@@ -0,0 +1,2 @@
+* Tobias Schmidt <tobidt@gmail.com> @grobie
+* Johannes 'fish' Ziemke <github@freigeist.org> @discordianfish
diff --git a/vendor/github.com/prometheus/procfs/Makefile b/vendor/github.com/prometheus/procfs/Makefile
new file mode 100644
index 0000000000..947d7d8fa7
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/Makefile
@@ -0,0 +1,30 @@
+# Copyright 2018 The Prometheus Authors
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+include Makefile.common
+
+%/.unpacked: %.ttar
+	./ttar -C $(dir $*) -x -f $*.ttar
+	touch $@
+
+update_fixtures: fixtures.ttar sysfs/fixtures.ttar
+
+%fixtures.ttar: %/fixtures
+	rm -v $(dir $*)fixtures/.unpacked
+	./ttar -C $(dir $*) -c -f $*fixtures.ttar fixtures/
+
+.PHONY: build
+build:
+
+.PHONY: test
+test: fixtures/.unpacked sysfs/fixtures/.unpacked common-test
diff --git a/vendor/github.com/prometheus/procfs/Makefile.common b/vendor/github.com/prometheus/procfs/Makefile.common
new file mode 100644
index 0000000000..741579e60f
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/Makefile.common
@@ -0,0 +1,223 @@
+# Copyright 2018 The Prometheus Authors
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+# A common Makefile that includes rules to be reused in different prometheus projects.
+# !!! Open PRs only against the prometheus/prometheus/Makefile.common repository!
+
+# Example usage :
+# Create the main Makefile in the root project directory.
+# include Makefile.common
+# customTarget:
+# 	@echo ">> Running customTarget"
+#
+
+# Ensure GOBIN is not set during build so that promu is installed to the correct path
+unexport GOBIN
+
+GO           ?= go
+GOFMT        ?= $(GO)fmt
+FIRST_GOPATH := $(firstword $(subst :, ,$(shell $(GO) env GOPATH)))
+GOOPTS       ?=
+
+GO_VERSION        ?= $(shell $(GO) version)
+GO_VERSION_NUMBER ?= $(word 3, $(GO_VERSION))
+PRE_GO_111        ?= $(shell echo $(GO_VERSION_NUMBER) | grep -E 'go1\.(10|[0-9])\.')
+
+unexport GOVENDOR
+ifeq (, $(PRE_GO_111))
+	ifneq (,$(wildcard go.mod))
+		# Enforce Go modules support just in case the directory is inside GOPATH (and for Travis CI).
+		GO111MODULE := on
+
+		ifneq (,$(wildcard vendor))
+			# Always use the local vendor/ directory to satisfy the dependencies.
+			GOOPTS := $(GOOPTS) -mod=vendor
+		endif
+	endif
+else
+	ifneq (,$(wildcard go.mod))
+		ifneq (,$(wildcard vendor))
+$(warning This repository requires Go >= 1.11 because of Go modules)
+$(warning Some recipes may not work as expected as the current Go runtime is '$(GO_VERSION_NUMBER)')
+		endif
+	else
+		# This repository isn't using Go modules (yet).
+		GOVENDOR := $(FIRST_GOPATH)/bin/govendor
+	endif
+
+	unexport GO111MODULE
+endif
+PROMU        := $(FIRST_GOPATH)/bin/promu
+STATICCHECK  := $(FIRST_GOPATH)/bin/staticcheck
+pkgs          = ./...
+
+GO_VERSION        ?= $(shell $(GO) version)
+GO_BUILD_PLATFORM ?= $(subst /,-,$(lastword $(GO_VERSION)))
+
+PROMU_VERSION ?= 0.2.0
+PROMU_URL     := https://github.com/prometheus/promu/releases/download/v$(PROMU_VERSION)/promu-$(PROMU_VERSION).$(GO_BUILD_PLATFORM).tar.gz
+
+PREFIX                  ?= $(shell pwd)
+BIN_DIR                 ?= $(shell pwd)
+DOCKER_IMAGE_TAG        ?= $(subst /,-,$(shell git rev-parse --abbrev-ref HEAD))
+DOCKER_REPO             ?= prom
+
+.PHONY: all
+all: precheck style staticcheck unused build test
+
+# This rule is used to forward a target like "build" to "common-build".  This
+# allows a new "build" target to be defined in a Makefile which includes this
+# one and override "common-build" without override warnings.
+%: common-% ;
+
+.PHONY: common-style
+common-style:
+	@echo ">> checking code style"
+	@fmtRes=$$($(GOFMT) -d $$(find . -path ./vendor -prune -o -name '*.go' -print)); \
+	if [ -n "$${fmtRes}" ]; then \
+		echo "gofmt checking failed!"; echo "$${fmtRes}"; echo; \
+		echo "Please ensure you are using $$($(GO) version) for formatting code."; \
+		exit 1; \
+	fi
+
+.PHONY: common-check_license
+common-check_license:
+	@echo ">> checking license header"
+	@licRes=$$(for file in $$(find . -type f -iname '*.go' ! -path './vendor/*') ; do \
+               awk 'NR<=3' $$file | grep -Eq "(Copyright|generated|GENERATED)" || echo $$file; \
+       done); \
+       if [ -n "$${licRes}" ]; then \
+               echo "license header checking failed:"; echo "$${licRes}"; \
+               exit 1; \
+       fi
+
+.PHONY: common-test-short
+common-test-short:
+	@echo ">> running short tests"
+	GO111MODULE=$(GO111MODULE) $(GO) test -short $(GOOPTS) $(pkgs)
+
+.PHONY: common-test
+common-test:
+	@echo ">> running all tests"
+	GO111MODULE=$(GO111MODULE) $(GO) test -race $(GOOPTS) $(pkgs)
+
+.PHONY: common-format
+common-format:
+	@echo ">> formatting code"
+	GO111MODULE=$(GO111MODULE) $(GO) fmt $(GOOPTS) $(pkgs)
+
+.PHONY: common-vet
+common-vet:
+	@echo ">> vetting code"
+	GO111MODULE=$(GO111MODULE) $(GO) vet $(GOOPTS) $(pkgs)
+
+.PHONY: common-staticcheck
+common-staticcheck: $(STATICCHECK)
+	@echo ">> running staticcheck"
+ifdef GO111MODULE
+	GO111MODULE=$(GO111MODULE) $(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs)
+else
+	$(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs)
+endif
+
+.PHONY: common-unused
+common-unused: $(GOVENDOR)
+ifdef GOVENDOR
+	@echo ">> running check for unused packages"
+	@$(GOVENDOR) list +unused | grep . && exit 1 || echo 'No unused packages'
+else
+ifdef GO111MODULE
+	@echo ">> running check for unused/missing packages in go.mod"
+	GO111MODULE=$(GO111MODULE) $(GO) mod tidy
+	@git diff --exit-code -- go.sum go.mod
+ifneq (,$(wildcard vendor))
+	@echo ">> running check for unused packages in vendor/"
+	GO111MODULE=$(GO111MODULE) $(GO) mod vendor
+	@git diff --exit-code -- go.sum go.mod vendor/
+endif
+endif
+endif
+
+.PHONY: common-build
+common-build: promu
+	@echo ">> building binaries"
+	GO111MODULE=$(GO111MODULE) $(PROMU) build --prefix $(PREFIX)
+
+.PHONY: common-tarball
+common-tarball: promu
+	@echo ">> building release tarball"
+	$(PROMU) tarball --prefix $(PREFIX) $(BIN_DIR)
+
+.PHONY: common-docker
+common-docker:
+	docker build -t "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" .
+
+.PHONY: common-docker-publish
+common-docker-publish:
+	docker push "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME)"
+
+.PHONY: common-docker-tag-latest
+common-docker-tag-latest:
+	docker tag "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):$(DOCKER_IMAGE_TAG)" "$(DOCKER_REPO)/$(DOCKER_IMAGE_NAME):latest"
+
+.PHONY: promu
+promu: $(PROMU)
+
+$(PROMU):
+	curl -s -L $(PROMU_URL) | tar -xvz -C /tmp
+	mkdir -v -p $(FIRST_GOPATH)/bin
+	cp -v /tmp/promu-$(PROMU_VERSION).$(GO_BUILD_PLATFORM)/promu $(PROMU)
+
+.PHONY: proto
+proto:
+	@echo ">> generating code from proto files"
+	@./scripts/genproto.sh
+
+.PHONY: $(STATICCHECK)
+$(STATICCHECK):
+ifdef GO111MODULE
+# Get staticcheck from a temporary directory to avoid modifying the local go.{mod,sum}.
+# See https://github.com/golang/go/issues/27643.
+# For now, we are using the next branch of staticcheck because master isn't compatible yet with Go modules.
+	tmpModule=$$(mktemp -d 2>&1) && \
+	mkdir -p $${tmpModule}/staticcheck && \
+	cd "$${tmpModule}"/staticcheck && \
+	GO111MODULE=on $(GO) mod init example.com/staticcheck && \
+	GO111MODULE=on GOOS= GOARCH= $(GO) get -u honnef.co/go/tools/cmd/staticcheck@next && \
+	rm -rf $${tmpModule};
+else
+	GOOS= GOARCH= GO111MODULE=off $(GO) get -u honnef.co/go/tools/cmd/staticcheck
+endif
+
+ifdef GOVENDOR
+.PHONY: $(GOVENDOR)
+$(GOVENDOR):
+	GOOS= GOARCH= $(GO) get -u github.com/kardianos/govendor
+endif
+
+.PHONY: precheck
+precheck::
+
+define PRECHECK_COMMAND_template =
+precheck:: $(1)_precheck
+
+
+PRECHECK_COMMAND_$(1) ?= $(1) $$(strip $$(PRECHECK_OPTIONS_$(1)))
+.PHONY: $(1)_precheck
+$(1)_precheck:
+	@if ! $$(PRECHECK_COMMAND_$(1)) 1>/dev/null 2>&1; then \
+		echo "Execution of '$$(PRECHECK_COMMAND_$(1))' command failed. Is $(1) installed?"; \
+		exit 1; \
+	fi
+endef
diff --git a/vendor/github.com/prometheus/procfs/NOTICE b/vendor/github.com/prometheus/procfs/NOTICE
new file mode 100644
index 0000000000..53c5e9aa11
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/NOTICE
@@ -0,0 +1,7 @@
+procfs provides functions to retrieve system, kernel and process
+metrics from the pseudo-filesystem proc.
+
+Copyright 2014-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
diff --git a/vendor/github.com/prometheus/procfs/README.md b/vendor/github.com/prometheus/procfs/README.md
new file mode 100644
index 0000000000..2095494719
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/README.md
@@ -0,0 +1,11 @@
+# procfs
+
+This procfs package provides functions to retrieve system, kernel and process
+metrics from the pseudo-filesystem proc.
+
+*WARNING*: This package is a work in progress. Its API may still break in
+backwards-incompatible ways without warnings. Use it at your own risk.
+
+[![GoDoc](https://godoc.org/github.com/prometheus/procfs?status.png)](https://godoc.org/github.com/prometheus/procfs)
+[![Build Status](https://travis-ci.org/prometheus/procfs.svg?branch=master)](https://travis-ci.org/prometheus/procfs)
+[![Go Report Card](https://goreportcard.com/badge/github.com/prometheus/procfs)](https://goreportcard.com/report/github.com/prometheus/procfs)
diff --git a/vendor/github.com/prometheus/procfs/buddyinfo.go b/vendor/github.com/prometheus/procfs/buddyinfo.go
new file mode 100644
index 0000000000..d3a8268078
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/buddyinfo.go
@@ -0,0 +1,95 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// A BuddyInfo is the details parsed from /proc/buddyinfo.
+// The data is comprised of an array of free fragments of each size.
+// The sizes are 2^n*PAGE_SIZE, where n is the array index.
+type BuddyInfo struct {
+	Node  string
+	Zone  string
+	Sizes []float64
+}
+
+// NewBuddyInfo reads the buddyinfo statistics.
+func NewBuddyInfo() ([]BuddyInfo, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewBuddyInfo()
+}
+
+// NewBuddyInfo reads the buddyinfo statistics from the specified `proc` filesystem.
+func (fs FS) NewBuddyInfo() ([]BuddyInfo, error) {
+	file, err := os.Open(fs.Path("buddyinfo"))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseBuddyInfo(file)
+}
+
+func parseBuddyInfo(r io.Reader) ([]BuddyInfo, error) {
+	var (
+		buddyInfo   = []BuddyInfo{}
+		scanner     = bufio.NewScanner(r)
+		bucketCount = -1
+	)
+
+	for scanner.Scan() {
+		var err error
+		line := scanner.Text()
+		parts := strings.Fields(line)
+
+		if len(parts) < 4 {
+			return nil, fmt.Errorf("invalid number of fields when parsing buddyinfo")
+		}
+
+		node := strings.TrimRight(parts[1], ",")
+		zone := strings.TrimRight(parts[3], ",")
+		arraySize := len(parts[4:])
+
+		if bucketCount == -1 {
+			bucketCount = arraySize
+		} else {
+			if bucketCount != arraySize {
+				return nil, fmt.Errorf("mismatch in number of buddyinfo buckets, previous count %d, new count %d", bucketCount, arraySize)
+			}
+		}
+
+		sizes := make([]float64, arraySize)
+		for i := 0; i < arraySize; i++ {
+			sizes[i], err = strconv.ParseFloat(parts[i+4], 64)
+			if err != nil {
+				return nil, fmt.Errorf("invalid value in buddyinfo: %s", err)
+			}
+		}
+
+		buddyInfo = append(buddyInfo, BuddyInfo{node, zone, sizes})
+	}
+
+	return buddyInfo, scanner.Err()
+}
diff --git a/vendor/github.com/prometheus/procfs/diskstats.go b/vendor/github.com/prometheus/procfs/diskstats.go
new file mode 100644
index 0000000000..a116cf3954
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/diskstats.go
@@ -0,0 +1,81 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/prometheus/procfs/iostats"
+)
+
+const (
+	diskstatsFilename = "diskstats"
+	statFormat        = "%d %d %s %d %d %d %d %d %d %d %d %d %d %d %d %d %d %d"
+)
+
+// NewDiskstats reads the diskstats file and returns
+// an array of Diskstats (one per line/device)
+func NewDiskstats() ([]iostats.IODeviceStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewDiskstats()
+}
+
+// NewDiskstats reads the diskstats file and returns
+// an array of Diskstats (one per line/device)
+func (fs FS) NewDiskstats() ([]iostats.IODeviceStats, error) {
+	file, err := os.Open(fs.Path(diskstatsFilename))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	diskstats := []iostats.IODeviceStats{}
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		d := &iostats.IODeviceStats{}
+		count, err := fmt.Sscanf(scanner.Text(), statFormat,
+			&d.MajorNumber,
+			&d.MinorNumber,
+			&d.DeviceName,
+			&d.ReadIOs,
+			&d.ReadMerges,
+			&d.ReadSectors,
+			&d.ReadTicks,
+			&d.WriteIOs,
+			&d.WriteMerges,
+			&d.WriteSectors,
+			&d.WriteTicks,
+			&d.IOsInProgress,
+			&d.IOsTotalTicks,
+			&d.WeightedIOTicks,
+			&d.DiscardIOs,
+			&d.DiscardMerges,
+			&d.DiscardSectors,
+			&d.DiscardTicks)
+		if err != nil && err != io.EOF {
+			return diskstats, err
+		}
+		if count == 14 || count == 18 {
+			diskstats = append(diskstats, *d)
+		}
+	}
+	return diskstats, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/doc.go b/vendor/github.com/prometheus/procfs/doc.go
new file mode 100644
index 0000000000..e2acd6d40a
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/doc.go
@@ -0,0 +1,45 @@
+// Copyright 2014 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package procfs provides functions to retrieve system, kernel and process
+// metrics from the pseudo-filesystem proc.
+//
+// Example:
+//
+//    package main
+//
+//    import (
+//    	"fmt"
+//    	"log"
+//
+//    	"github.com/prometheus/procfs"
+//    )
+//
+//    func main() {
+//    	p, err := procfs.Self()
+//    	if err != nil {
+//    		log.Fatalf("could not get process: %s", err)
+//    	}
+//
+//    	stat, err := p.NewStat()
+//    	if err != nil {
+//    		log.Fatalf("could not get process stat: %s", err)
+//    	}
+//
+//    	fmt.Printf("command:  %s\n", stat.Comm)
+//    	fmt.Printf("cpu time: %fs\n", stat.CPUTime())
+//    	fmt.Printf("vsize:    %dB\n", stat.VirtualMemory())
+//    	fmt.Printf("rss:      %dB\n", stat.ResidentMemory())
+//    }
+//
+package procfs
diff --git a/vendor/github.com/prometheus/procfs/fixtures.ttar b/vendor/github.com/prometheus/procfs/fixtures.ttar
new file mode 100644
index 0000000000..dbd91ceef8
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/fixtures.ttar
@@ -0,0 +1,535 @@
+# Archive created by ttar -c -f fixtures.ttar fixtures/
+Directory: fixtures
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Directory: fixtures/26231
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/cmdline
+Lines: 1
+vimNULLBYTEtest.goNULLBYTE+10NULLBYTEEOF
+Mode: 644
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/comm
+Lines: 1
+vim
+Mode: 644
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/cwd
+SymlinkTo: /usr/bin
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/exe
+SymlinkTo: /usr/bin/vim
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Directory: fixtures/26231/fd
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/fd/0
+SymlinkTo: ../../symlinktargets/abc
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/fd/1
+SymlinkTo: ../../symlinktargets/def
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/fd/10
+SymlinkTo: ../../symlinktargets/xyz
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/fd/2
+SymlinkTo: ../../symlinktargets/ghi
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/fd/3
+SymlinkTo: ../../symlinktargets/uvw
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/io
+Lines: 7
+rchar: 750339
+wchar: 818609
+syscr: 7405
+syscw: 5245
+read_bytes: 1024
+write_bytes: 2048
+cancelled_write_bytes: -1024
+Mode: 644
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/limits
+Lines: 17
+Limit                     Soft Limit           Hard Limit           Units
+Max cpu time              unlimited            unlimited            seconds
+Max file size             unlimited            unlimited            bytes
+Max data size             unlimited            unlimited            bytes
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+Max resident set          unlimited            unlimited            bytes
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+Max nice priority         0                    0
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+Mode: 644
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/mountstats
+Lines: 19
+device rootfs mounted on / with fstype rootfs
+device sysfs mounted on /sys with fstype sysfs
+device proc mounted on /proc with fstype proc
+device /dev/sda1 mounted on / with fstype ext4
+device 192.168.1.1:/srv/test mounted on /mnt/nfs/test with fstype nfs4 statvers=1.1
+	opts:	rw,vers=4.0,rsize=1048576,wsize=1048576,namlen=255,acregmin=3,acregmax=60,acdirmin=30,acdirmax=60,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=192.168.1.5,local_lock=none
+	age:	13968
+	caps:	caps=0xfff7,wtmult=512,dtsize=32768,bsize=0,namlen=255
+	nfsv4:	bm0=0xfdffafff,bm1=0xf9be3e,bm2=0x0,acl=0x0,pnfs=not configured
+	sec:	flavor=1,pseudoflavor=1
+	events:	52 226 0 0 1 13 398 0 0 331 0 47 0 0 77 0 0 77 0 0 0 0 0 0 0 0 0
+	bytes:	1207640230 0 0 0 1210214218 0 295483 0
+	RPC iostats version: 1.0  p/v: 100003/4 (nfs)
+	xprt:	tcp 832 0 1 0 11 6428 6428 0 12154 0 24 26 5726
+	per-op statistics
+	        NULL: 0 0 0 0 0 0 0 0
+	        READ: 1298 1298 0 207680 1210292152 6 79386 79407
+	       WRITE: 0 0 0 0 0 0 0 0
+
+Mode: 644
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Directory: fixtures/26231/net
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/net/dev
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+Mode: 644
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+Directory: fixtures/26231/ns
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+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/ns/mnt
+SymlinkTo: mnt:[4026531840]
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/ns/net
+SymlinkTo: net:[4026531993]
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: fixtures/26231/root
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diff --git a/vendor/github.com/prometheus/procfs/fs.go b/vendor/github.com/prometheus/procfs/fs.go
new file mode 100644
index 0000000000..b6c6b2ce1f
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/fs.go
@@ -0,0 +1,82 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"path"
+
+	"github.com/prometheus/procfs/nfs"
+	"github.com/prometheus/procfs/xfs"
+)
+
+// FS represents the pseudo-filesystem proc, which provides an interface to
+// kernel data structures.
+type FS string
+
+// DefaultMountPoint is the common mount point of the proc filesystem.
+const DefaultMountPoint = "/proc"
+
+// NewFS returns a new FS mounted under the given mountPoint. It will error
+// if the mount point can't be read.
+func NewFS(mountPoint string) (FS, error) {
+	info, err := os.Stat(mountPoint)
+	if err != nil {
+		return "", fmt.Errorf("could not read %s: %s", mountPoint, err)
+	}
+	if !info.IsDir() {
+		return "", fmt.Errorf("mount point %s is not a directory", mountPoint)
+	}
+
+	return FS(mountPoint), nil
+}
+
+// Path returns the path of the given subsystem relative to the procfs root.
+func (fs FS) Path(p ...string) string {
+	return path.Join(append([]string{string(fs)}, p...)...)
+}
+
+// XFSStats retrieves XFS filesystem runtime statistics.
+func (fs FS) XFSStats() (*xfs.Stats, error) {
+	f, err := os.Open(fs.Path("fs/xfs/stat"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return xfs.ParseStats(f)
+}
+
+// NFSClientRPCStats retrieves NFS client RPC statistics.
+func (fs FS) NFSClientRPCStats() (*nfs.ClientRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfs"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseClientRPCStats(f)
+}
+
+// NFSdServerRPCStats retrieves NFS daemon RPC statistics.
+func (fs FS) NFSdServerRPCStats() (*nfs.ServerRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfsd"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseServerRPCStats(f)
+}
diff --git a/vendor/github.com/prometheus/procfs/go.mod b/vendor/github.com/prometheus/procfs/go.mod
new file mode 100644
index 0000000000..8a1b839fd2
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/go.mod
@@ -0,0 +1,3 @@
+module github.com/prometheus/procfs
+
+require golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4
diff --git a/vendor/github.com/prometheus/procfs/go.sum b/vendor/github.com/prometheus/procfs/go.sum
new file mode 100644
index 0000000000..7827dd3d56
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/go.sum
@@ -0,0 +1,2 @@
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4 h1:YUO/7uOKsKeq9UokNS62b8FYywz3ker1l1vDZRCRefw=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
diff --git a/vendor/github.com/prometheus/procfs/internal/util/parse.go b/vendor/github.com/prometheus/procfs/internal/util/parse.go
new file mode 100644
index 0000000000..ca74889a1b
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/internal/util/parse.go
@@ -0,0 +1,73 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package util
+
+import (
+	"io/ioutil"
+	"strconv"
+	"strings"
+)
+
+// ParseUint32s parses a slice of strings into a slice of uint32s.
+func ParseUint32s(ss []string) ([]uint32, error) {
+	us := make([]uint32, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, uint32(u))
+	}
+
+	return us, nil
+}
+
+// ParseUint64s parses a slice of strings into a slice of uint64s.
+func ParseUint64s(ss []string) ([]uint64, error) {
+	us := make([]uint64, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, u)
+	}
+
+	return us, nil
+}
+
+// ReadUintFromFile reads a file and attempts to parse a uint64 from it.
+func ReadUintFromFile(path string) (uint64, error) {
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.ParseUint(strings.TrimSpace(string(data)), 10, 64)
+}
+
+// ParseBool parses a string into a boolean pointer.
+func ParseBool(b string) *bool {
+	var truth bool
+	switch b {
+	case "enabled":
+		truth = true
+	case "disabled":
+		truth = false
+	default:
+		return nil
+	}
+	return &truth
+}
diff --git a/vendor/github.com/prometheus/procfs/internal/util/sysreadfile_linux.go b/vendor/github.com/prometheus/procfs/internal/util/sysreadfile_linux.go
new file mode 100644
index 0000000000..df0d567b78
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/internal/util/sysreadfile_linux.go
@@ -0,0 +1,45 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !windows
+
+package util
+
+import (
+	"bytes"
+	"os"
+	"syscall"
+)
+
+// SysReadFile is a simplified ioutil.ReadFile that invokes syscall.Read directly.
+// https://github.com/prometheus/node_exporter/pull/728/files
+func SysReadFile(file string) (string, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	// On some machines, hwmon drivers are broken and return EAGAIN.  This causes
+	// Go's ioutil.ReadFile implementation to poll forever.
+	//
+	// Since we either want to read data or bail immediately, do the simplest
+	// possible read using syscall directly.
+	b := make([]byte, 128)
+	n, err := syscall.Read(int(f.Fd()), b)
+	if err != nil {
+		return "", err
+	}
+
+	return string(bytes.TrimSpace(b[:n])), nil
+}
diff --git a/vendor/github.com/prometheus/procfs/iostats/iostats.go b/vendor/github.com/prometheus/procfs/iostats/iostats.go
new file mode 100644
index 0000000000..97e8314762
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/iostats/iostats.go
@@ -0,0 +1,67 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package iostats
+
+// IODevice contains identifying information for an I/O device
+type IODevice struct {
+	MajorNumber uint32
+	MinorNumber uint32
+	DeviceName  string
+}
+
+// IOStats models the iostats data described in the kernel documentation
+// https://www.kernel.org/doc/Documentation/iostats.txt,
+// https://www.kernel.org/doc/Documentation/block/stat.txt,
+// and https://www.kernel.org/doc/Documentation/ABI/testing/procfs-diskstats
+type IOStats struct {
+	// ReadIOs is the number of reads completed successfully.
+	ReadIOs uint64
+	// ReadMerges is the number of reads merged.  Reads and writes
+	// which are adjacent to each other may be merged for efficiency.
+	ReadMerges uint64
+	// ReadSectors is the total number of sectors read successfully.
+	ReadSectors uint64
+	// ReadTicks is the total number of milliseconds spent by all reads.
+	ReadTicks uint64
+	// WriteIOs is the total number of writes completed successfully.
+	WriteIOs uint64
+	// WriteMerges is the number of reads merged.
+	WriteMerges uint64
+	// WriteSectors is the total number of sectors written successfully.
+	WriteSectors uint64
+	// WriteTicks is the total number of milliseconds spent by all writes.
+	WriteTicks uint64
+	// IOsInProgress is number of I/Os currently in progress.
+	IOsInProgress uint64
+	// IOsTotalTicks is the number of milliseconds spent doing I/Os.
+	// This field increases so long as IosInProgress is nonzero.
+	IOsTotalTicks uint64
+	// WeightedIOTicks is the weighted number of milliseconds spent doing I/Os.
+	// This can also be used to estimate average queue wait time for requests.
+	WeightedIOTicks uint64
+	// DiscardIOs is the total number of discards completed successfully.
+	DiscardIOs uint64
+	// DiscardMerges is the number of discards merged.
+	DiscardMerges uint64
+	// DiscardSectors is the total number of sectors discarded successfully.
+	DiscardSectors uint64
+	// DiscardTicks is the total number of milliseconds spent by all discards.
+	DiscardTicks uint64
+}
+
+// IODeviceStats combines IODevice and IOStats
+type IODeviceStats struct {
+	IODevice
+	IOStats
+}
diff --git a/vendor/github.com/prometheus/procfs/ipvs.go b/vendor/github.com/prometheus/procfs/ipvs.go
new file mode 100644
index 0000000000..e36d4a3bd0
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/ipvs.go
@@ -0,0 +1,259 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// IPVSStats holds IPVS statistics, as exposed by the kernel in `/proc/net/ip_vs_stats`.
+type IPVSStats struct {
+	// Total count of connections.
+	Connections uint64
+	// Total incoming packages processed.
+	IncomingPackets uint64
+	// Total outgoing packages processed.
+	OutgoingPackets uint64
+	// Total incoming traffic.
+	IncomingBytes uint64
+	// Total outgoing traffic.
+	OutgoingBytes uint64
+}
+
+// IPVSBackendStatus holds current metrics of one virtual / real address pair.
+type IPVSBackendStatus struct {
+	// The local (virtual) IP address.
+	LocalAddress net.IP
+	// The remote (real) IP address.
+	RemoteAddress net.IP
+	// The local (virtual) port.
+	LocalPort uint16
+	// The remote (real) port.
+	RemotePort uint16
+	// The local firewall mark
+	LocalMark string
+	// The transport protocol (TCP, UDP).
+	Proto string
+	// The current number of active connections for this virtual/real address pair.
+	ActiveConn uint64
+	// The current number of inactive connections for this virtual/real address pair.
+	InactConn uint64
+	// The current weight of this virtual/real address pair.
+	Weight uint64
+}
+
+// NewIPVSStats reads the IPVS statistics.
+func NewIPVSStats() (IPVSStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return fs.NewIPVSStats()
+}
+
+// NewIPVSStats reads the IPVS statistics from the specified `proc` filesystem.
+func (fs FS) NewIPVSStats() (IPVSStats, error) {
+	file, err := os.Open(fs.Path("net/ip_vs_stats"))
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	defer file.Close()
+
+	return parseIPVSStats(file)
+}
+
+// parseIPVSStats performs the actual parsing of `ip_vs_stats`.
+func parseIPVSStats(file io.Reader) (IPVSStats, error) {
+	var (
+		statContent []byte
+		statLines   []string
+		statFields  []string
+		stats       IPVSStats
+	)
+
+	statContent, err := ioutil.ReadAll(file)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	statLines = strings.SplitN(string(statContent), "\n", 4)
+	if len(statLines) != 4 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: too short")
+	}
+
+	statFields = strings.Fields(statLines[2])
+	if len(statFields) != 5 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: unexpected number of fields")
+	}
+
+	stats.Connections, err = strconv.ParseUint(statFields[0], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingPackets, err = strconv.ParseUint(statFields[1], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingPackets, err = strconv.ParseUint(statFields[2], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingBytes, err = strconv.ParseUint(statFields[3], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingBytes, err = strconv.ParseUint(statFields[4], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return stats, nil
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs.
+func NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return []IPVSBackendStatus{}, err
+	}
+
+	return fs.NewIPVSBackendStatus()
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs from the specified `proc` filesystem.
+func (fs FS) NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	file, err := os.Open(fs.Path("net/ip_vs"))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseIPVSBackendStatus(file)
+}
+
+func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
+	var (
+		status       []IPVSBackendStatus
+		scanner      = bufio.NewScanner(file)
+		proto        string
+		localMark    string
+		localAddress net.IP
+		localPort    uint16
+		err          error
+	)
+
+	for scanner.Scan() {
+		fields := strings.Fields(scanner.Text())
+		if len(fields) == 0 {
+			continue
+		}
+		switch {
+		case fields[0] == "IP" || fields[0] == "Prot" || fields[1] == "RemoteAddress:Port":
+			continue
+		case fields[0] == "TCP" || fields[0] == "UDP":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localMark = ""
+			localAddress, localPort, err = parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+		case fields[0] == "FWM":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localMark = fields[1]
+			localAddress = nil
+			localPort = 0
+		case fields[0] == "->":
+			if len(fields) < 6 {
+				continue
+			}
+			remoteAddress, remotePort, err := parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+			weight, err := strconv.ParseUint(fields[3], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			activeConn, err := strconv.ParseUint(fields[4], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			inactConn, err := strconv.ParseUint(fields[5], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			status = append(status, IPVSBackendStatus{
+				LocalAddress:  localAddress,
+				LocalPort:     localPort,
+				LocalMark:     localMark,
+				RemoteAddress: remoteAddress,
+				RemotePort:    remotePort,
+				Proto:         proto,
+				Weight:        weight,
+				ActiveConn:    activeConn,
+				InactConn:     inactConn,
+			})
+		}
+	}
+	return status, nil
+}
+
+func parseIPPort(s string) (net.IP, uint16, error) {
+	var (
+		ip  net.IP
+		err error
+	)
+
+	switch len(s) {
+	case 13:
+		ip, err = hex.DecodeString(s[0:8])
+		if err != nil {
+			return nil, 0, err
+		}
+	case 46:
+		ip = net.ParseIP(s[1:40])
+		if ip == nil {
+			return nil, 0, fmt.Errorf("invalid IPv6 address: %s", s[1:40])
+		}
+	default:
+		return nil, 0, fmt.Errorf("unexpected IP:Port: %s", s)
+	}
+
+	portString := s[len(s)-4:]
+	if len(portString) != 4 {
+		return nil, 0, fmt.Errorf("unexpected port string format: %s", portString)
+	}
+	port, err := strconv.ParseUint(portString, 16, 16)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return ip, uint16(port), nil
+}
diff --git a/vendor/github.com/prometheus/procfs/mdstat.go b/vendor/github.com/prometheus/procfs/mdstat.go
new file mode 100644
index 0000000000..9dc19583d8
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/mdstat.go
@@ -0,0 +1,151 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var (
+	statuslineRE = regexp.MustCompile(`(\d+) blocks .*\[(\d+)/(\d+)\] \[[U_]+\]`)
+	buildlineRE  = regexp.MustCompile(`\((\d+)/\d+\)`)
+)
+
+// MDStat holds info parsed from /proc/mdstat.
+type MDStat struct {
+	// Name of the device.
+	Name string
+	// activity-state of the device.
+	ActivityState string
+	// Number of active disks.
+	DisksActive int64
+	// Total number of disks the device consists of.
+	DisksTotal int64
+	// Number of blocks the device holds.
+	BlocksTotal int64
+	// Number of blocks on the device that are in sync.
+	BlocksSynced int64
+}
+
+// ParseMDStat parses an mdstat-file and returns a struct with the relevant infos.
+func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
+	mdStatusFilePath := fs.Path("mdstat")
+	content, err := ioutil.ReadFile(mdStatusFilePath)
+	if err != nil {
+		return []MDStat{}, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+	}
+
+	mdStates := []MDStat{}
+	lines := strings.Split(string(content), "\n")
+	for i, l := range lines {
+		if l == "" {
+			continue
+		}
+		if l[0] == ' ' {
+			continue
+		}
+		if strings.HasPrefix(l, "Personalities") || strings.HasPrefix(l, "unused") {
+			continue
+		}
+
+		mainLine := strings.Split(l, " ")
+		if len(mainLine) < 3 {
+			return mdStates, fmt.Errorf("error parsing mdline: %s", l)
+		}
+		mdName := mainLine[0]
+		activityState := mainLine[2]
+
+		if len(lines) <= i+3 {
+			return mdStates, fmt.Errorf(
+				"error parsing %s: too few lines for md device %s",
+				mdStatusFilePath,
+				mdName,
+			)
+		}
+
+		active, total, size, err := evalStatusline(lines[i+1])
+		if err != nil {
+			return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+		}
+
+		// j is the line number of the syncing-line.
+		j := i + 2
+		if strings.Contains(lines[i+2], "bitmap") { // skip bitmap line
+			j = i + 3
+		}
+
+		// If device is syncing at the moment, get the number of currently
+		// synced bytes, otherwise that number equals the size of the device.
+		syncedBlocks := size
+		if strings.Contains(lines[j], "recovery") || strings.Contains(lines[j], "resync") {
+			syncedBlocks, err = evalBuildline(lines[j])
+			if err != nil {
+				return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+			}
+		}
+
+		mdStates = append(mdStates, MDStat{
+			Name:          mdName,
+			ActivityState: activityState,
+			DisksActive:   active,
+			DisksTotal:    total,
+			BlocksTotal:   size,
+			BlocksSynced:  syncedBlocks,
+		})
+	}
+
+	return mdStates, nil
+}
+
+func evalStatusline(statusline string) (active, total, size int64, err error) {
+	matches := statuslineRE.FindStringSubmatch(statusline)
+	if len(matches) != 4 {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline: %s", statusline)
+	}
+
+	size, err = strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	total, err = strconv.ParseInt(matches[2], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	active, err = strconv.ParseInt(matches[3], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	return active, total, size, nil
+}
+
+func evalBuildline(buildline string) (syncedBlocks int64, err error) {
+	matches := buildlineRE.FindStringSubmatch(buildline)
+	if len(matches) != 2 {
+		return 0, fmt.Errorf("unexpected buildline: %s", buildline)
+	}
+
+	syncedBlocks, err = strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("%s in buildline: %s", err, buildline)
+	}
+
+	return syncedBlocks, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/mountstats.go b/vendor/github.com/prometheus/procfs/mountstats.go
new file mode 100644
index 0000000000..fc385afcfe
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/mountstats.go
@@ -0,0 +1,616 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+// While implementing parsing of /proc/[pid]/mountstats, this blog was used
+// heavily as a reference:
+//   https://utcc.utoronto.ca/~cks/space/blog/linux/NFSMountstatsIndex
+//
+// Special thanks to Chris Siebenmann for all of his posts explaining the
+// various statistics available for NFS.
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Constants shared between multiple functions.
+const (
+	deviceEntryLen = 8
+
+	fieldBytesLen  = 8
+	fieldEventsLen = 27
+
+	statVersion10 = "1.0"
+	statVersion11 = "1.1"
+
+	fieldTransport10TCPLen = 10
+	fieldTransport10UDPLen = 7
+
+	fieldTransport11TCPLen = 13
+	fieldTransport11UDPLen = 10
+)
+
+// A Mount is a device mount parsed from /proc/[pid]/mountstats.
+type Mount struct {
+	// Name of the device.
+	Device string
+	// The mount point of the device.
+	Mount string
+	// The filesystem type used by the device.
+	Type string
+	// If available additional statistics related to this Mount.
+	// Use a type assertion to determine if additional statistics are available.
+	Stats MountStats
+}
+
+// A MountStats is a type which contains detailed statistics for a specific
+// type of Mount.
+type MountStats interface {
+	mountStats()
+}
+
+// A MountStatsNFS is a MountStats implementation for NFSv3 and v4 mounts.
+type MountStatsNFS struct {
+	// The version of statistics provided.
+	StatVersion string
+	// The optional mountaddr of the NFS mount.
+	MountAddress string
+	// The age of the NFS mount.
+	Age time.Duration
+	// Statistics related to byte counters for various operations.
+	Bytes NFSBytesStats
+	// Statistics related to various NFS event occurrences.
+	Events NFSEventsStats
+	// Statistics broken down by filesystem operation.
+	Operations []NFSOperationStats
+	// Statistics about the NFS RPC transport.
+	Transport NFSTransportStats
+}
+
+// mountStats implements MountStats.
+func (m MountStatsNFS) mountStats() {}
+
+// A NFSBytesStats contains statistics about the number of bytes read and written
+// by an NFS client to and from an NFS server.
+type NFSBytesStats struct {
+	// Number of bytes read using the read() syscall.
+	Read uint64
+	// Number of bytes written using the write() syscall.
+	Write uint64
+	// Number of bytes read using the read() syscall in O_DIRECT mode.
+	DirectRead uint64
+	// Number of bytes written using the write() syscall in O_DIRECT mode.
+	DirectWrite uint64
+	// Number of bytes read from the NFS server, in total.
+	ReadTotal uint64
+	// Number of bytes written to the NFS server, in total.
+	WriteTotal uint64
+	// Number of pages read directly via mmap()'d files.
+	ReadPages uint64
+	// Number of pages written directly via mmap()'d files.
+	WritePages uint64
+}
+
+// A NFSEventsStats contains statistics about NFS event occurrences.
+type NFSEventsStats struct {
+	// Number of times cached inode attributes are re-validated from the server.
+	InodeRevalidate uint64
+	// Number of times cached dentry nodes are re-validated from the server.
+	DnodeRevalidate uint64
+	// Number of times an inode cache is cleared.
+	DataInvalidate uint64
+	// Number of times cached inode attributes are invalidated.
+	AttributeInvalidate uint64
+	// Number of times files or directories have been open()'d.
+	VFSOpen uint64
+	// Number of times a directory lookup has occurred.
+	VFSLookup uint64
+	// Number of times permissions have been checked.
+	VFSAccess uint64
+	// Number of updates (and potential writes) to pages.
+	VFSUpdatePage uint64
+	// Number of pages read directly via mmap()'d files.
+	VFSReadPage uint64
+	// Number of times a group of pages have been read.
+	VFSReadPages uint64
+	// Number of pages written directly via mmap()'d files.
+	VFSWritePage uint64
+	// Number of times a group of pages have been written.
+	VFSWritePages uint64
+	// Number of times directory entries have been read with getdents().
+	VFSGetdents uint64
+	// Number of times attributes have been set on inodes.
+	VFSSetattr uint64
+	// Number of pending writes that have been forcefully flushed to the server.
+	VFSFlush uint64
+	// Number of times fsync() has been called on directories and files.
+	VFSFsync uint64
+	// Number of times locking has been attempted on a file.
+	VFSLock uint64
+	// Number of times files have been closed and released.
+	VFSFileRelease uint64
+	// Unknown.  Possibly unused.
+	CongestionWait uint64
+	// Number of times files have been truncated.
+	Truncation uint64
+	// Number of times a file has been grown due to writes beyond its existing end.
+	WriteExtension uint64
+	// Number of times a file was removed while still open by another process.
+	SillyRename uint64
+	// Number of times the NFS server gave less data than expected while reading.
+	ShortRead uint64
+	// Number of times the NFS server wrote less data than expected while writing.
+	ShortWrite uint64
+	// Number of times the NFS server indicated EJUKEBOX; retrieving data from
+	// offline storage.
+	JukeboxDelay uint64
+	// Number of NFS v4.1+ pNFS reads.
+	PNFSRead uint64
+	// Number of NFS v4.1+ pNFS writes.
+	PNFSWrite uint64
+}
+
+// A NFSOperationStats contains statistics for a single operation.
+type NFSOperationStats struct {
+	// The name of the operation.
+	Operation string
+	// Number of requests performed for this operation.
+	Requests uint64
+	// Number of times an actual RPC request has been transmitted for this operation.
+	Transmissions uint64
+	// Number of times a request has had a major timeout.
+	MajorTimeouts uint64
+	// Number of bytes sent for this operation, including RPC headers and payload.
+	BytesSent uint64
+	// Number of bytes received for this operation, including RPC headers and payload.
+	BytesReceived uint64
+	// Duration all requests spent queued for transmission before they were sent.
+	CumulativeQueueTime time.Duration
+	// Duration it took to get a reply back after the request was transmitted.
+	CumulativeTotalResponseTime time.Duration
+	// Duration from when a request was enqueued to when it was completely handled.
+	CumulativeTotalRequestTime time.Duration
+}
+
+// A NFSTransportStats contains statistics for the NFS mount RPC requests and
+// responses.
+type NFSTransportStats struct {
+	// The transport protocol used for the NFS mount.
+	Protocol string
+	// The local port used for the NFS mount.
+	Port uint64
+	// Number of times the client has had to establish a connection from scratch
+	// to the NFS server.
+	Bind uint64
+	// Number of times the client has made a TCP connection to the NFS server.
+	Connect uint64
+	// Duration (in jiffies, a kernel internal unit of time) the NFS mount has
+	// spent waiting for connections to the server to be established.
+	ConnectIdleTime uint64
+	// Duration since the NFS mount last saw any RPC traffic.
+	IdleTime time.Duration
+	// Number of RPC requests for this mount sent to the NFS server.
+	Sends uint64
+	// Number of RPC responses for this mount received from the NFS server.
+	Receives uint64
+	// Number of times the NFS server sent a response with a transaction ID
+	// unknown to this client.
+	BadTransactionIDs uint64
+	// A running counter, incremented on each request as the current difference
+	// ebetween sends and receives.
+	CumulativeActiveRequests uint64
+	// A running counter, incremented on each request by the current backlog
+	// queue size.
+	CumulativeBacklog uint64
+
+	// Stats below only available with stat version 1.1.
+
+	// Maximum number of simultaneously active RPC requests ever used.
+	MaximumRPCSlotsUsed uint64
+	// A running counter, incremented on each request as the current size of the
+	// sending queue.
+	CumulativeSendingQueue uint64
+	// A running counter, incremented on each request as the current size of the
+	// pending queue.
+	CumulativePendingQueue uint64
+}
+
+// parseMountStats parses a /proc/[pid]/mountstats file and returns a slice
+// of Mount structures containing detailed information about each mount.
+// If available, statistics for each mount are parsed as well.
+func parseMountStats(r io.Reader) ([]*Mount, error) {
+	const (
+		device            = "device"
+		statVersionPrefix = "statvers="
+
+		nfs3Type = "nfs"
+		nfs4Type = "nfs4"
+	)
+
+	var mounts []*Mount
+
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		// Only look for device entries in this function
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 || ss[0] != device {
+			continue
+		}
+
+		m, err := parseMount(ss)
+		if err != nil {
+			return nil, err
+		}
+
+		// Does this mount also possess statistics information?
+		if len(ss) > deviceEntryLen {
+			// Only NFSv3 and v4 are supported for parsing statistics
+			if m.Type != nfs3Type && m.Type != nfs4Type {
+				return nil, fmt.Errorf("cannot parse MountStats for fstype %q", m.Type)
+			}
+
+			statVersion := strings.TrimPrefix(ss[8], statVersionPrefix)
+
+			stats, err := parseMountStatsNFS(s, statVersion)
+			if err != nil {
+				return nil, err
+			}
+
+			m.Stats = stats
+		}
+
+		mounts = append(mounts, m)
+	}
+
+	return mounts, s.Err()
+}
+
+// parseMount parses an entry in /proc/[pid]/mountstats in the format:
+//   device [device] mounted on [mount] with fstype [type]
+func parseMount(ss []string) (*Mount, error) {
+	if len(ss) < deviceEntryLen {
+		return nil, fmt.Errorf("invalid device entry: %v", ss)
+	}
+
+	// Check for specific words appearing at specific indices to ensure
+	// the format is consistent with what we expect
+	format := []struct {
+		i int
+		s string
+	}{
+		{i: 0, s: "device"},
+		{i: 2, s: "mounted"},
+		{i: 3, s: "on"},
+		{i: 5, s: "with"},
+		{i: 6, s: "fstype"},
+	}
+
+	for _, f := range format {
+		if ss[f.i] != f.s {
+			return nil, fmt.Errorf("invalid device entry: %v", ss)
+		}
+	}
+
+	return &Mount{
+		Device: ss[1],
+		Mount:  ss[4],
+		Type:   ss[7],
+	}, nil
+}
+
+// parseMountStatsNFS parses a MountStatsNFS by scanning additional information
+// related to NFS statistics.
+func parseMountStatsNFS(s *bufio.Scanner, statVersion string) (*MountStatsNFS, error) {
+	// Field indicators for parsing specific types of data
+	const (
+		fieldOpts       = "opts:"
+		fieldAge        = "age:"
+		fieldBytes      = "bytes:"
+		fieldEvents     = "events:"
+		fieldPerOpStats = "per-op"
+		fieldTransport  = "xprt:"
+	)
+
+	stats := &MountStatsNFS{
+		StatVersion: statVersion,
+	}
+
+	for s.Scan() {
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 {
+			break
+		}
+		if len(ss) < 2 {
+			return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+		}
+
+		switch ss[0] {
+		case fieldOpts:
+			for _, opt := range strings.Split(ss[1], ",") {
+				split := strings.Split(opt, "=")
+				if len(split) == 2 && split[0] == "mountaddr" {
+					stats.MountAddress = split[1]
+				}
+			}
+		case fieldAge:
+			// Age integer is in seconds
+			d, err := time.ParseDuration(ss[1] + "s")
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Age = d
+		case fieldBytes:
+			bstats, err := parseNFSBytesStats(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Bytes = *bstats
+		case fieldEvents:
+			estats, err := parseNFSEventsStats(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Events = *estats
+		case fieldTransport:
+			if len(ss) < 3 {
+				return nil, fmt.Errorf("not enough information for NFS transport stats: %v", ss)
+			}
+
+			tstats, err := parseNFSTransportStats(ss[1:], statVersion)
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Transport = *tstats
+		}
+
+		// When encountering "per-operation statistics", we must break this
+		// loop and parse them separately to ensure we can terminate parsing
+		// before reaching another device entry; hence why this 'if' statement
+		// is not just another switch case
+		if ss[0] == fieldPerOpStats {
+			break
+		}
+	}
+
+	if err := s.Err(); err != nil {
+		return nil, err
+	}
+
+	// NFS per-operation stats appear last before the next device entry
+	perOpStats, err := parseNFSOperationStats(s)
+	if err != nil {
+		return nil, err
+	}
+
+	stats.Operations = perOpStats
+
+	return stats, nil
+}
+
+// parseNFSBytesStats parses a NFSBytesStats line using an input set of
+// integer fields.
+func parseNFSBytesStats(ss []string) (*NFSBytesStats, error) {
+	if len(ss) != fieldBytesLen {
+		return nil, fmt.Errorf("invalid NFS bytes stats: %v", ss)
+	}
+
+	ns := make([]uint64, 0, fieldBytesLen)
+	for _, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns = append(ns, n)
+	}
+
+	return &NFSBytesStats{
+		Read:        ns[0],
+		Write:       ns[1],
+		DirectRead:  ns[2],
+		DirectWrite: ns[3],
+		ReadTotal:   ns[4],
+		WriteTotal:  ns[5],
+		ReadPages:   ns[6],
+		WritePages:  ns[7],
+	}, nil
+}
+
+// parseNFSEventsStats parses a NFSEventsStats line using an input set of
+// integer fields.
+func parseNFSEventsStats(ss []string) (*NFSEventsStats, error) {
+	if len(ss) != fieldEventsLen {
+		return nil, fmt.Errorf("invalid NFS events stats: %v", ss)
+	}
+
+	ns := make([]uint64, 0, fieldEventsLen)
+	for _, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns = append(ns, n)
+	}
+
+	return &NFSEventsStats{
+		InodeRevalidate:     ns[0],
+		DnodeRevalidate:     ns[1],
+		DataInvalidate:      ns[2],
+		AttributeInvalidate: ns[3],
+		VFSOpen:             ns[4],
+		VFSLookup:           ns[5],
+		VFSAccess:           ns[6],
+		VFSUpdatePage:       ns[7],
+		VFSReadPage:         ns[8],
+		VFSReadPages:        ns[9],
+		VFSWritePage:        ns[10],
+		VFSWritePages:       ns[11],
+		VFSGetdents:         ns[12],
+		VFSSetattr:          ns[13],
+		VFSFlush:            ns[14],
+		VFSFsync:            ns[15],
+		VFSLock:             ns[16],
+		VFSFileRelease:      ns[17],
+		CongestionWait:      ns[18],
+		Truncation:          ns[19],
+		WriteExtension:      ns[20],
+		SillyRename:         ns[21],
+		ShortRead:           ns[22],
+		ShortWrite:          ns[23],
+		JukeboxDelay:        ns[24],
+		PNFSRead:            ns[25],
+		PNFSWrite:           ns[26],
+	}, nil
+}
+
+// parseNFSOperationStats parses a slice of NFSOperationStats by scanning
+// additional information about per-operation statistics until an empty
+// line is reached.
+func parseNFSOperationStats(s *bufio.Scanner) ([]NFSOperationStats, error) {
+	const (
+		// Number of expected fields in each per-operation statistics set
+		numFields = 9
+	)
+
+	var ops []NFSOperationStats
+
+	for s.Scan() {
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 {
+			// Must break when reading a blank line after per-operation stats to
+			// enable top-level function to parse the next device entry
+			break
+		}
+
+		if len(ss) != numFields {
+			return nil, fmt.Errorf("invalid NFS per-operations stats: %v", ss)
+		}
+
+		// Skip string operation name for integers
+		ns := make([]uint64, 0, numFields-1)
+		for _, st := range ss[1:] {
+			n, err := strconv.ParseUint(st, 10, 64)
+			if err != nil {
+				return nil, err
+			}
+
+			ns = append(ns, n)
+		}
+
+		ops = append(ops, NFSOperationStats{
+			Operation:                   strings.TrimSuffix(ss[0], ":"),
+			Requests:                    ns[0],
+			Transmissions:               ns[1],
+			MajorTimeouts:               ns[2],
+			BytesSent:                   ns[3],
+			BytesReceived:               ns[4],
+			CumulativeQueueTime:         time.Duration(ns[5]) * time.Millisecond,
+			CumulativeTotalResponseTime: time.Duration(ns[6]) * time.Millisecond,
+			CumulativeTotalRequestTime:  time.Duration(ns[7]) * time.Millisecond,
+		})
+	}
+
+	return ops, s.Err()
+}
+
+// parseNFSTransportStats parses a NFSTransportStats line using an input set of
+// integer fields matched to a specific stats version.
+func parseNFSTransportStats(ss []string, statVersion string) (*NFSTransportStats, error) {
+	// Extract the protocol field. It is the only string value in the line
+	protocol := ss[0]
+	ss = ss[1:]
+
+	switch statVersion {
+	case statVersion10:
+		var expectedLength int
+		if protocol == "tcp" {
+			expectedLength = fieldTransport10TCPLen
+		} else if protocol == "udp" {
+			expectedLength = fieldTransport10UDPLen
+		} else {
+			return nil, fmt.Errorf("invalid NFS protocol \"%s\" in stats 1.0 statement: %v", protocol, ss)
+		}
+		if len(ss) != expectedLength {
+			return nil, fmt.Errorf("invalid NFS transport stats 1.0 statement: %v", ss)
+		}
+	case statVersion11:
+		var expectedLength int
+		if protocol == "tcp" {
+			expectedLength = fieldTransport11TCPLen
+		} else if protocol == "udp" {
+			expectedLength = fieldTransport11UDPLen
+		} else {
+			return nil, fmt.Errorf("invalid NFS protocol \"%s\" in stats 1.1 statement: %v", protocol, ss)
+		}
+		if len(ss) != expectedLength {
+			return nil, fmt.Errorf("invalid NFS transport stats 1.1 statement: %v", ss)
+		}
+	default:
+		return nil, fmt.Errorf("unrecognized NFS transport stats version: %q", statVersion)
+	}
+
+	// Allocate enough for v1.1 stats since zero value for v1.1 stats will be okay
+	// in a v1.0 response. Since the stat length is bigger for TCP stats, we use
+	// the TCP length here.
+	//
+	// Note: slice length must be set to length of v1.1 stats to avoid a panic when
+	// only v1.0 stats are present.
+	// See: https://github.com/prometheus/node_exporter/issues/571.
+	ns := make([]uint64, fieldTransport11TCPLen)
+	for i, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns[i] = n
+	}
+
+	// The fields differ depending on the transport protocol (TCP or UDP)
+	// From https://utcc.utoronto.ca/%7Ecks/space/blog/linux/NFSMountstatsXprt
+	//
+	// For the udp RPC transport there is no connection count, connect idle time,
+	// or idle time (fields #3, #4, and #5); all other fields are the same. So
+	// we set them to 0 here.
+	if protocol == "udp" {
+		ns = append(ns[:2], append(make([]uint64, 3), ns[2:]...)...)
+	}
+
+	return &NFSTransportStats{
+		Protocol:                 protocol,
+		Port:                     ns[0],
+		Bind:                     ns[1],
+		Connect:                  ns[2],
+		ConnectIdleTime:          ns[3],
+		IdleTime:                 time.Duration(ns[4]) * time.Second,
+		Sends:                    ns[5],
+		Receives:                 ns[6],
+		BadTransactionIDs:        ns[7],
+		CumulativeActiveRequests: ns[8],
+		CumulativeBacklog:        ns[9],
+		MaximumRPCSlotsUsed:      ns[10],
+		CumulativeSendingQueue:   ns[11],
+		CumulativePendingQueue:   ns[12],
+	}, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/net_dev.go b/vendor/github.com/prometheus/procfs/net_dev.go
new file mode 100644
index 0000000000..3f2523371a
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/net_dev.go
@@ -0,0 +1,216 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"errors"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// NetDevLine is single line parsed from /proc/net/dev or /proc/[pid]/net/dev.
+type NetDevLine struct {
+	Name         string `json:"name"`          // The name of the interface.
+	RxBytes      uint64 `json:"rx_bytes"`      // Cumulative count of bytes received.
+	RxPackets    uint64 `json:"rx_packets"`    // Cumulative count of packets received.
+	RxErrors     uint64 `json:"rx_errors"`     // Cumulative count of receive errors encountered.
+	RxDropped    uint64 `json:"rx_dropped"`    // Cumulative count of packets dropped while receiving.
+	RxFIFO       uint64 `json:"rx_fifo"`       // Cumulative count of FIFO buffer errors.
+	RxFrame      uint64 `json:"rx_frame"`      // Cumulative count of packet framing errors.
+	RxCompressed uint64 `json:"rx_compressed"` // Cumulative count of compressed packets received by the device driver.
+	RxMulticast  uint64 `json:"rx_multicast"`  // Cumulative count of multicast frames received by the device driver.
+	TxBytes      uint64 `json:"tx_bytes"`      // Cumulative count of bytes transmitted.
+	TxPackets    uint64 `json:"tx_packets"`    // Cumulative count of packets transmitted.
+	TxErrors     uint64 `json:"tx_errors"`     // Cumulative count of transmit errors encountered.
+	TxDropped    uint64 `json:"tx_dropped"`    // Cumulative count of packets dropped while transmitting.
+	TxFIFO       uint64 `json:"tx_fifo"`       // Cumulative count of FIFO buffer errors.
+	TxCollisions uint64 `json:"tx_collisions"` // Cumulative count of collisions detected on the interface.
+	TxCarrier    uint64 `json:"tx_carrier"`    // Cumulative count of carrier losses detected by the device driver.
+	TxCompressed uint64 `json:"tx_compressed"` // Cumulative count of compressed packets transmitted by the device driver.
+}
+
+// NetDev is parsed from /proc/net/dev or /proc/[pid]/net/dev. The map keys
+// are interface names.
+type NetDev map[string]NetDevLine
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func NewNetDev() (NetDev, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewNetDev()
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func (fs FS) NewNetDev() (NetDev, error) {
+	return newNetDev(fs.Path("net/dev"))
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/[pid]/net/dev.
+func (p Proc) NewNetDev() (NetDev, error) {
+	return newNetDev(p.path("net/dev"))
+}
+
+// newNetDev creates a new NetDev from the contents of the given file.
+func newNetDev(file string) (NetDev, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return NetDev{}, err
+	}
+	defer f.Close()
+
+	nd := NetDev{}
+	s := bufio.NewScanner(f)
+	for n := 0; s.Scan(); n++ {
+		// Skip the 2 header lines.
+		if n < 2 {
+			continue
+		}
+
+		line, err := nd.parseLine(s.Text())
+		if err != nil {
+			return nd, err
+		}
+
+		nd[line.Name] = *line
+	}
+
+	return nd, s.Err()
+}
+
+// parseLine parses a single line from the /proc/net/dev file. Header lines
+// must be filtered prior to calling this method.
+func (nd NetDev) parseLine(rawLine string) (*NetDevLine, error) {
+	parts := strings.SplitN(rawLine, ":", 2)
+	if len(parts) != 2 {
+		return nil, errors.New("invalid net/dev line, missing colon")
+	}
+	fields := strings.Fields(strings.TrimSpace(parts[1]))
+
+	var err error
+	line := &NetDevLine{}
+
+	// Interface Name
+	line.Name = strings.TrimSpace(parts[0])
+	if line.Name == "" {
+		return nil, errors.New("invalid net/dev line, empty interface name")
+	}
+
+	// RX
+	line.RxBytes, err = strconv.ParseUint(fields[0], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxPackets, err = strconv.ParseUint(fields[1], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxErrors, err = strconv.ParseUint(fields[2], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxDropped, err = strconv.ParseUint(fields[3], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFIFO, err = strconv.ParseUint(fields[4], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFrame, err = strconv.ParseUint(fields[5], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxCompressed, err = strconv.ParseUint(fields[6], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxMulticast, err = strconv.ParseUint(fields[7], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	// TX
+	line.TxBytes, err = strconv.ParseUint(fields[8], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxPackets, err = strconv.ParseUint(fields[9], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxErrors, err = strconv.ParseUint(fields[10], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxDropped, err = strconv.ParseUint(fields[11], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxFIFO, err = strconv.ParseUint(fields[12], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCollisions, err = strconv.ParseUint(fields[13], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCarrier, err = strconv.ParseUint(fields[14], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCompressed, err = strconv.ParseUint(fields[15], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	return line, nil
+}
+
+// Total aggregates the values across interfaces and returns a new NetDevLine.
+// The Name field will be a sorted comma separated list of interface names.
+func (nd NetDev) Total() NetDevLine {
+	total := NetDevLine{}
+
+	names := make([]string, 0, len(nd))
+	for _, ifc := range nd {
+		names = append(names, ifc.Name)
+		total.RxBytes += ifc.RxBytes
+		total.RxPackets += ifc.RxPackets
+		total.RxPackets += ifc.RxPackets
+		total.RxErrors += ifc.RxErrors
+		total.RxDropped += ifc.RxDropped
+		total.RxFIFO += ifc.RxFIFO
+		total.RxFrame += ifc.RxFrame
+		total.RxCompressed += ifc.RxCompressed
+		total.RxMulticast += ifc.RxMulticast
+		total.TxBytes += ifc.TxBytes
+		total.TxPackets += ifc.TxPackets
+		total.TxErrors += ifc.TxErrors
+		total.TxDropped += ifc.TxDropped
+		total.TxFIFO += ifc.TxFIFO
+		total.TxCollisions += ifc.TxCollisions
+		total.TxCarrier += ifc.TxCarrier
+		total.TxCompressed += ifc.TxCompressed
+	}
+	sort.Strings(names)
+	total.Name = strings.Join(names, ", ")
+
+	return total
+}
diff --git a/vendor/github.com/prometheus/procfs/nfs/nfs.go b/vendor/github.com/prometheus/procfs/nfs/nfs.go
new file mode 100644
index 0000000000..651bf68195
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/nfs/nfs.go
@@ -0,0 +1,263 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package nfs implements parsing of /proc/net/rpc/nfsd.
+// Fields are documented in https://www.svennd.be/nfsd-stats-explained-procnetrpcnfsd/
+package nfs
+
+// ReplyCache models the "rc" line.
+type ReplyCache struct {
+	Hits    uint64
+	Misses  uint64
+	NoCache uint64
+}
+
+// FileHandles models the "fh" line.
+type FileHandles struct {
+	Stale        uint64
+	TotalLookups uint64
+	AnonLookups  uint64
+	DirNoCache   uint64
+	NoDirNoCache uint64
+}
+
+// InputOutput models the "io" line.
+type InputOutput struct {
+	Read  uint64
+	Write uint64
+}
+
+// Threads models the "th" line.
+type Threads struct {
+	Threads uint64
+	FullCnt uint64
+}
+
+// ReadAheadCache models the "ra" line.
+type ReadAheadCache struct {
+	CacheSize      uint64
+	CacheHistogram []uint64
+	NotFound       uint64
+}
+
+// Network models the "net" line.
+type Network struct {
+	NetCount   uint64
+	UDPCount   uint64
+	TCPCount   uint64
+	TCPConnect uint64
+}
+
+// ClientRPC models the nfs "rpc" line.
+type ClientRPC struct {
+	RPCCount        uint64
+	Retransmissions uint64
+	AuthRefreshes   uint64
+}
+
+// ServerRPC models the nfsd "rpc" line.
+type ServerRPC struct {
+	RPCCount uint64
+	BadCnt   uint64
+	BadFmt   uint64
+	BadAuth  uint64
+	BadcInt  uint64
+}
+
+// V2Stats models the "proc2" line.
+type V2Stats struct {
+	Null     uint64
+	GetAttr  uint64
+	SetAttr  uint64
+	Root     uint64
+	Lookup   uint64
+	ReadLink uint64
+	Read     uint64
+	WrCache  uint64
+	Write    uint64
+	Create   uint64
+	Remove   uint64
+	Rename   uint64
+	Link     uint64
+	SymLink  uint64
+	MkDir    uint64
+	RmDir    uint64
+	ReadDir  uint64
+	FsStat   uint64
+}
+
+// V3Stats models the "proc3" line.
+type V3Stats struct {
+	Null        uint64
+	GetAttr     uint64
+	SetAttr     uint64
+	Lookup      uint64
+	Access      uint64
+	ReadLink    uint64
+	Read        uint64
+	Write       uint64
+	Create      uint64
+	MkDir       uint64
+	SymLink     uint64
+	MkNod       uint64
+	Remove      uint64
+	RmDir       uint64
+	Rename      uint64
+	Link        uint64
+	ReadDir     uint64
+	ReadDirPlus uint64
+	FsStat      uint64
+	FsInfo      uint64
+	PathConf    uint64
+	Commit      uint64
+}
+
+// ClientV4Stats models the nfs "proc4" line.
+type ClientV4Stats struct {
+	Null               uint64
+	Read               uint64
+	Write              uint64
+	Commit             uint64
+	Open               uint64
+	OpenConfirm        uint64
+	OpenNoattr         uint64
+	OpenDowngrade      uint64
+	Close              uint64
+	Setattr            uint64
+	FsInfo             uint64
+	Renew              uint64
+	SetClientID        uint64
+	SetClientIDConfirm uint64
+	Lock               uint64
+	Lockt              uint64
+	Locku              uint64
+	Access             uint64
+	Getattr            uint64
+	Lookup             uint64
+	LookupRoot         uint64
+	Remove             uint64
+	Rename             uint64
+	Link               uint64
+	Symlink            uint64
+	Create             uint64
+	Pathconf           uint64
+	StatFs             uint64
+	ReadLink           uint64
+	ReadDir            uint64
+	ServerCaps         uint64
+	DelegReturn        uint64
+	GetACL             uint64
+	SetACL             uint64
+	FsLocations        uint64
+	ReleaseLockowner   uint64
+	Secinfo            uint64
+	FsidPresent        uint64
+	ExchangeID         uint64
+	CreateSession      uint64
+	DestroySession     uint64
+	Sequence           uint64
+	GetLeaseTime       uint64
+	ReclaimComplete    uint64
+	LayoutGet          uint64
+	GetDeviceInfo      uint64
+	LayoutCommit       uint64
+	LayoutReturn       uint64
+	SecinfoNoName      uint64
+	TestStateID        uint64
+	FreeStateID        uint64
+	GetDeviceList      uint64
+	BindConnToSession  uint64
+	DestroyClientID    uint64
+	Seek               uint64
+	Allocate           uint64
+	DeAllocate         uint64
+	LayoutStats        uint64
+	Clone              uint64
+}
+
+// ServerV4Stats models the nfsd "proc4" line.
+type ServerV4Stats struct {
+	Null     uint64
+	Compound uint64
+}
+
+// V4Ops models the "proc4ops" line: NFSv4 operations
+// Variable list, see:
+// v4.0 https://tools.ietf.org/html/rfc3010 (38 operations)
+// v4.1 https://tools.ietf.org/html/rfc5661 (58 operations)
+// v4.2 https://tools.ietf.org/html/draft-ietf-nfsv4-minorversion2-41 (71 operations)
+type V4Ops struct {
+	//Values       uint64 // Variable depending on v4.x sub-version. TODO: Will this always at least include the fields in this struct?
+	Op0Unused    uint64
+	Op1Unused    uint64
+	Op2Future    uint64
+	Access       uint64
+	Close        uint64
+	Commit       uint64
+	Create       uint64
+	DelegPurge   uint64
+	DelegReturn  uint64
+	GetAttr      uint64
+	GetFH        uint64
+	Link         uint64
+	Lock         uint64
+	Lockt        uint64
+	Locku        uint64
+	Lookup       uint64
+	LookupRoot   uint64
+	Nverify      uint64
+	Open         uint64
+	OpenAttr     uint64
+	OpenConfirm  uint64
+	OpenDgrd     uint64
+	PutFH        uint64
+	PutPubFH     uint64
+	PutRootFH    uint64
+	Read         uint64
+	ReadDir      uint64
+	ReadLink     uint64
+	Remove       uint64
+	Rename       uint64
+	Renew        uint64
+	RestoreFH    uint64
+	SaveFH       uint64
+	SecInfo      uint64
+	SetAttr      uint64
+	Verify       uint64
+	Write        uint64
+	RelLockOwner uint64
+}
+
+// ClientRPCStats models all stats from /proc/net/rpc/nfs.
+type ClientRPCStats struct {
+	Network       Network
+	ClientRPC     ClientRPC
+	V2Stats       V2Stats
+	V3Stats       V3Stats
+	ClientV4Stats ClientV4Stats
+}
+
+// ServerRPCStats models all stats from /proc/net/rpc/nfsd.
+type ServerRPCStats struct {
+	ReplyCache     ReplyCache
+	FileHandles    FileHandles
+	InputOutput    InputOutput
+	Threads        Threads
+	ReadAheadCache ReadAheadCache
+	Network        Network
+	ServerRPC      ServerRPC
+	V2Stats        V2Stats
+	V3Stats        V3Stats
+	ServerV4Stats  ServerV4Stats
+	V4Ops          V4Ops
+}
diff --git a/vendor/github.com/prometheus/procfs/nfs/parse.go b/vendor/github.com/prometheus/procfs/nfs/parse.go
new file mode 100644
index 0000000000..95a83cc5bc
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/nfs/parse.go
@@ -0,0 +1,317 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"fmt"
+)
+
+func parseReplyCache(v []uint64) (ReplyCache, error) {
+	if len(v) != 3 {
+		return ReplyCache{}, fmt.Errorf("invalid ReplyCache line %q", v)
+	}
+
+	return ReplyCache{
+		Hits:    v[0],
+		Misses:  v[1],
+		NoCache: v[2],
+	}, nil
+}
+
+func parseFileHandles(v []uint64) (FileHandles, error) {
+	if len(v) != 5 {
+		return FileHandles{}, fmt.Errorf("invalid FileHandles, line %q", v)
+	}
+
+	return FileHandles{
+		Stale:        v[0],
+		TotalLookups: v[1],
+		AnonLookups:  v[2],
+		DirNoCache:   v[3],
+		NoDirNoCache: v[4],
+	}, nil
+}
+
+func parseInputOutput(v []uint64) (InputOutput, error) {
+	if len(v) != 2 {
+		return InputOutput{}, fmt.Errorf("invalid InputOutput line %q", v)
+	}
+
+	return InputOutput{
+		Read:  v[0],
+		Write: v[1],
+	}, nil
+}
+
+func parseThreads(v []uint64) (Threads, error) {
+	if len(v) != 2 {
+		return Threads{}, fmt.Errorf("invalid Threads line %q", v)
+	}
+
+	return Threads{
+		Threads: v[0],
+		FullCnt: v[1],
+	}, nil
+}
+
+func parseReadAheadCache(v []uint64) (ReadAheadCache, error) {
+	if len(v) != 12 {
+		return ReadAheadCache{}, fmt.Errorf("invalid ReadAheadCache line %q", v)
+	}
+
+	return ReadAheadCache{
+		CacheSize:      v[0],
+		CacheHistogram: v[1:11],
+		NotFound:       v[11],
+	}, nil
+}
+
+func parseNetwork(v []uint64) (Network, error) {
+	if len(v) != 4 {
+		return Network{}, fmt.Errorf("invalid Network line %q", v)
+	}
+
+	return Network{
+		NetCount:   v[0],
+		UDPCount:   v[1],
+		TCPCount:   v[2],
+		TCPConnect: v[3],
+	}, nil
+}
+
+func parseServerRPC(v []uint64) (ServerRPC, error) {
+	if len(v) != 5 {
+		return ServerRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ServerRPC{
+		RPCCount: v[0],
+		BadCnt:   v[1],
+		BadFmt:   v[2],
+		BadAuth:  v[3],
+		BadcInt:  v[4],
+	}, nil
+}
+
+func parseClientRPC(v []uint64) (ClientRPC, error) {
+	if len(v) != 3 {
+		return ClientRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ClientRPC{
+		RPCCount:        v[0],
+		Retransmissions: v[1],
+		AuthRefreshes:   v[2],
+	}, nil
+}
+
+func parseV2Stats(v []uint64) (V2Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 18 {
+		return V2Stats{}, fmt.Errorf("invalid V2Stats line %q", v)
+	}
+
+	return V2Stats{
+		Null:     v[1],
+		GetAttr:  v[2],
+		SetAttr:  v[3],
+		Root:     v[4],
+		Lookup:   v[5],
+		ReadLink: v[6],
+		Read:     v[7],
+		WrCache:  v[8],
+		Write:    v[9],
+		Create:   v[10],
+		Remove:   v[11],
+		Rename:   v[12],
+		Link:     v[13],
+		SymLink:  v[14],
+		MkDir:    v[15],
+		RmDir:    v[16],
+		ReadDir:  v[17],
+		FsStat:   v[18],
+	}, nil
+}
+
+func parseV3Stats(v []uint64) (V3Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 22 {
+		return V3Stats{}, fmt.Errorf("invalid V3Stats line %q", v)
+	}
+
+	return V3Stats{
+		Null:        v[1],
+		GetAttr:     v[2],
+		SetAttr:     v[3],
+		Lookup:      v[4],
+		Access:      v[5],
+		ReadLink:    v[6],
+		Read:        v[7],
+		Write:       v[8],
+		Create:      v[9],
+		MkDir:       v[10],
+		SymLink:     v[11],
+		MkNod:       v[12],
+		Remove:      v[13],
+		RmDir:       v[14],
+		Rename:      v[15],
+		Link:        v[16],
+		ReadDir:     v[17],
+		ReadDirPlus: v[18],
+		FsStat:      v[19],
+		FsInfo:      v[20],
+		PathConf:    v[21],
+		Commit:      v[22],
+	}, nil
+}
+
+func parseClientV4Stats(v []uint64) (ClientV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values {
+		return ClientV4Stats{}, fmt.Errorf("invalid ClientV4Stats line %q", v)
+	}
+
+	// This function currently supports mapping 59 NFS v4 client stats.  Older
+	// kernels may emit fewer stats, so we must detect this and pad out the
+	// values to match the expected slice size.
+	if values < 59 {
+		newValues := make([]uint64, 60)
+		copy(newValues, v)
+		v = newValues
+	}
+
+	return ClientV4Stats{
+		Null:               v[1],
+		Read:               v[2],
+		Write:              v[3],
+		Commit:             v[4],
+		Open:               v[5],
+		OpenConfirm:        v[6],
+		OpenNoattr:         v[7],
+		OpenDowngrade:      v[8],
+		Close:              v[9],
+		Setattr:            v[10],
+		FsInfo:             v[11],
+		Renew:              v[12],
+		SetClientID:        v[13],
+		SetClientIDConfirm: v[14],
+		Lock:               v[15],
+		Lockt:              v[16],
+		Locku:              v[17],
+		Access:             v[18],
+		Getattr:            v[19],
+		Lookup:             v[20],
+		LookupRoot:         v[21],
+		Remove:             v[22],
+		Rename:             v[23],
+		Link:               v[24],
+		Symlink:            v[25],
+		Create:             v[26],
+		Pathconf:           v[27],
+		StatFs:             v[28],
+		ReadLink:           v[29],
+		ReadDir:            v[30],
+		ServerCaps:         v[31],
+		DelegReturn:        v[32],
+		GetACL:             v[33],
+		SetACL:             v[34],
+		FsLocations:        v[35],
+		ReleaseLockowner:   v[36],
+		Secinfo:            v[37],
+		FsidPresent:        v[38],
+		ExchangeID:         v[39],
+		CreateSession:      v[40],
+		DestroySession:     v[41],
+		Sequence:           v[42],
+		GetLeaseTime:       v[43],
+		ReclaimComplete:    v[44],
+		LayoutGet:          v[45],
+		GetDeviceInfo:      v[46],
+		LayoutCommit:       v[47],
+		LayoutReturn:       v[48],
+		SecinfoNoName:      v[49],
+		TestStateID:        v[50],
+		FreeStateID:        v[51],
+		GetDeviceList:      v[52],
+		BindConnToSession:  v[53],
+		DestroyClientID:    v[54],
+		Seek:               v[55],
+		Allocate:           v[56],
+		DeAllocate:         v[57],
+		LayoutStats:        v[58],
+		Clone:              v[59],
+	}, nil
+}
+
+func parseServerV4Stats(v []uint64) (ServerV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 2 {
+		return ServerV4Stats{}, fmt.Errorf("invalid V4Stats line %q", v)
+	}
+
+	return ServerV4Stats{
+		Null:     v[1],
+		Compound: v[2],
+	}, nil
+}
+
+func parseV4Ops(v []uint64) (V4Ops, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values < 39 {
+		return V4Ops{}, fmt.Errorf("invalid V4Ops line %q", v)
+	}
+
+	stats := V4Ops{
+		Op0Unused:    v[1],
+		Op1Unused:    v[2],
+		Op2Future:    v[3],
+		Access:       v[4],
+		Close:        v[5],
+		Commit:       v[6],
+		Create:       v[7],
+		DelegPurge:   v[8],
+		DelegReturn:  v[9],
+		GetAttr:      v[10],
+		GetFH:        v[11],
+		Link:         v[12],
+		Lock:         v[13],
+		Lockt:        v[14],
+		Locku:        v[15],
+		Lookup:       v[16],
+		LookupRoot:   v[17],
+		Nverify:      v[18],
+		Open:         v[19],
+		OpenAttr:     v[20],
+		OpenConfirm:  v[21],
+		OpenDgrd:     v[22],
+		PutFH:        v[23],
+		PutPubFH:     v[24],
+		PutRootFH:    v[25],
+		Read:         v[26],
+		ReadDir:      v[27],
+		ReadLink:     v[28],
+		Remove:       v[29],
+		Rename:       v[30],
+		Renew:        v[31],
+		RestoreFH:    v[32],
+		SaveFH:       v[33],
+		SecInfo:      v[34],
+		SetAttr:      v[35],
+		Verify:       v[36],
+		Write:        v[37],
+		RelLockOwner: v[38],
+	}
+
+	return stats, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/nfs/parse_nfs.go b/vendor/github.com/prometheus/procfs/nfs/parse_nfs.go
new file mode 100644
index 0000000000..c0d3a5ad9b
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/nfs/parse_nfs.go
@@ -0,0 +1,67 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseClientRPCStats returns stats read from /proc/net/rpc/nfs
+func ParseClientRPCStats(r io.Reader) (*ClientRPCStats, error) {
+	stats := &ClientRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFS metric line %q", line)
+		}
+
+		values, err := util.ParseUint64s(parts[1:])
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFS metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ClientRPC, err = parseClientRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ClientV4Stats, err = parseClientV4Stats(values)
+		default:
+			return nil, fmt.Errorf("unknown NFS metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFS metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFS file: %s", err)
+	}
+
+	return stats, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/nfs/parse_nfsd.go b/vendor/github.com/prometheus/procfs/nfs/parse_nfsd.go
new file mode 100644
index 0000000000..57bb4a3585
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/nfs/parse_nfsd.go
@@ -0,0 +1,89 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseServerRPCStats returns stats read from /proc/net/rpc/nfsd
+func ParseServerRPCStats(r io.Reader) (*ServerRPCStats, error) {
+	stats := &ServerRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFSd metric line %q", line)
+		}
+		label := parts[0]
+
+		var values []uint64
+		var err error
+		if label == "th" {
+			if len(parts) < 3 {
+				return nil, fmt.Errorf("invalid NFSd th metric line %q", line)
+			}
+			values, err = util.ParseUint64s(parts[1:3])
+		} else {
+			values, err = util.ParseUint64s(parts[1:])
+		}
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFSd metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "rc":
+			stats.ReplyCache, err = parseReplyCache(values)
+		case "fh":
+			stats.FileHandles, err = parseFileHandles(values)
+		case "io":
+			stats.InputOutput, err = parseInputOutput(values)
+		case "th":
+			stats.Threads, err = parseThreads(values)
+		case "ra":
+			stats.ReadAheadCache, err = parseReadAheadCache(values)
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ServerRPC, err = parseServerRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ServerV4Stats, err = parseServerV4Stats(values)
+		case "proc4ops":
+			stats.V4Ops, err = parseV4Ops(values)
+		default:
+			return nil, fmt.Errorf("unknown NFSd metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFSd metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFSd file: %s", err)
+	}
+
+	return stats, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/proc.go b/vendor/github.com/prometheus/procfs/proc.go
new file mode 100644
index 0000000000..06bed0ef4a
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc.go
@@ -0,0 +1,258 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// Proc provides information about a running process.
+type Proc struct {
+	// The process ID.
+	PID int
+
+	fs FS
+}
+
+// Procs represents a list of Proc structs.
+type Procs []Proc
+
+func (p Procs) Len() int           { return len(p) }
+func (p Procs) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+func (p Procs) Less(i, j int) bool { return p[i].PID < p[j].PID }
+
+// Self returns a process for the current process read via /proc/self.
+func Self() (Proc, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.Self()
+}
+
+// NewProc returns a process for the given pid under /proc.
+func NewProc(pid int) (Proc, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.NewProc(pid)
+}
+
+// AllProcs returns a list of all currently available processes under /proc.
+func AllProcs() (Procs, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Procs{}, err
+	}
+	return fs.AllProcs()
+}
+
+// Self returns a process for the current process.
+func (fs FS) Self() (Proc, error) {
+	p, err := os.Readlink(fs.Path("self"))
+	if err != nil {
+		return Proc{}, err
+	}
+	pid, err := strconv.Atoi(strings.Replace(p, string(fs), "", -1))
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.NewProc(pid)
+}
+
+// NewProc returns a process for the given pid.
+func (fs FS) NewProc(pid int) (Proc, error) {
+	if _, err := os.Stat(fs.Path(strconv.Itoa(pid))); err != nil {
+		return Proc{}, err
+	}
+	return Proc{PID: pid, fs: fs}, nil
+}
+
+// AllProcs returns a list of all currently available processes.
+func (fs FS) AllProcs() (Procs, error) {
+	d, err := os.Open(fs.Path())
+	if err != nil {
+		return Procs{}, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return Procs{}, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	p := Procs{}
+	for _, n := range names {
+		pid, err := strconv.ParseInt(n, 10, 64)
+		if err != nil {
+			continue
+		}
+		p = append(p, Proc{PID: int(pid), fs: fs})
+	}
+
+	return p, nil
+}
+
+// CmdLine returns the command line of a process.
+func (p Proc) CmdLine() ([]string, error) {
+	f, err := os.Open(p.path("cmdline"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(data) < 1 {
+		return []string{}, nil
+	}
+
+	return strings.Split(string(bytes.TrimRight(data, string("\x00"))), string(byte(0))), nil
+}
+
+// Comm returns the command name of a process.
+func (p Proc) Comm() (string, error) {
+	f, err := os.Open(p.path("comm"))
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return "", err
+	}
+
+	return strings.TrimSpace(string(data)), nil
+}
+
+// Executable returns the absolute path of the executable command of a process.
+func (p Proc) Executable() (string, error) {
+	exe, err := os.Readlink(p.path("exe"))
+	if os.IsNotExist(err) {
+		return "", nil
+	}
+
+	return exe, err
+}
+
+// Cwd returns the absolute path to the current working directory of the process.
+func (p Proc) Cwd() (string, error) {
+	wd, err := os.Readlink(p.path("cwd"))
+	if os.IsNotExist(err) {
+		return "", nil
+	}
+
+	return wd, err
+}
+
+// RootDir returns the absolute path to the process's root directory (as set by chroot)
+func (p Proc) RootDir() (string, error) {
+	rdir, err := os.Readlink(p.path("root"))
+	if os.IsNotExist(err) {
+		return "", nil
+	}
+
+	return rdir, err
+}
+
+// FileDescriptors returns the currently open file descriptors of a process.
+func (p Proc) FileDescriptors() ([]uintptr, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	fds := make([]uintptr, len(names))
+	for i, n := range names {
+		fd, err := strconv.ParseInt(n, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse fd %s: %s", n, err)
+		}
+		fds[i] = uintptr(fd)
+	}
+
+	return fds, nil
+}
+
+// FileDescriptorTargets returns the targets of all file descriptors of a process.
+// If a file descriptor is not a symlink to a file (like a socket), that value will be the empty string.
+func (p Proc) FileDescriptorTargets() ([]string, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	targets := make([]string, len(names))
+
+	for i, name := range names {
+		target, err := os.Readlink(p.path("fd", name))
+		if err == nil {
+			targets[i] = target
+		}
+	}
+
+	return targets, nil
+}
+
+// FileDescriptorsLen returns the number of currently open file descriptors of
+// a process.
+func (p Proc) FileDescriptorsLen() (int, error) {
+	fds, err := p.fileDescriptors()
+	if err != nil {
+		return 0, err
+	}
+
+	return len(fds), nil
+}
+
+// MountStats retrieves statistics and configuration for mount points in a
+// process's namespace.
+func (p Proc) MountStats() ([]*Mount, error) {
+	f, err := os.Open(p.path("mountstats"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return parseMountStats(f)
+}
+
+func (p Proc) fileDescriptors() ([]string, error) {
+	d, err := os.Open(p.path("fd"))
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	return names, nil
+}
+
+func (p Proc) path(pa ...string) string {
+	return p.fs.Path(append([]string{strconv.Itoa(p.PID)}, pa...)...)
+}
diff --git a/vendor/github.com/prometheus/procfs/proc_io.go b/vendor/github.com/prometheus/procfs/proc_io.go
new file mode 100644
index 0000000000..0251c83bfe
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_io.go
@@ -0,0 +1,65 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+// ProcIO models the content of /proc/<pid>/io.
+type ProcIO struct {
+	// Chars read.
+	RChar uint64
+	// Chars written.
+	WChar uint64
+	// Read syscalls.
+	SyscR uint64
+	// Write syscalls.
+	SyscW uint64
+	// Bytes read.
+	ReadBytes uint64
+	// Bytes written.
+	WriteBytes uint64
+	// Bytes written, but taking into account truncation. See
+	// Documentation/filesystems/proc.txt in the kernel sources for
+	// detailed explanation.
+	CancelledWriteBytes int64
+}
+
+// NewIO creates a new ProcIO instance from a given Proc instance.
+func (p Proc) NewIO() (ProcIO, error) {
+	pio := ProcIO{}
+
+	f, err := os.Open(p.path("io"))
+	if err != nil {
+		return pio, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return pio, err
+	}
+
+	ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" +
+		"read_bytes: %d\nwrite_bytes: %d\n" +
+		"cancelled_write_bytes: %d\n"
+
+	_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
+		&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
+
+	return pio, err
+}
diff --git a/vendor/github.com/prometheus/procfs/proc_limits.go b/vendor/github.com/prometheus/procfs/proc_limits.go
new file mode 100644
index 0000000000..f04ba6fda8
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_limits.go
@@ -0,0 +1,150 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"regexp"
+	"strconv"
+)
+
+// ProcLimits represents the soft limits for each of the process's resource
+// limits. For more information see getrlimit(2):
+// http://man7.org/linux/man-pages/man2/getrlimit.2.html.
+type ProcLimits struct {
+	// CPU time limit in seconds.
+	CPUTime int64
+	// Maximum size of files that the process may create.
+	FileSize int64
+	// Maximum size of the process's data segment (initialized data,
+	// uninitialized data, and heap).
+	DataSize int64
+	// Maximum size of the process stack in bytes.
+	StackSize int64
+	// Maximum size of a core file.
+	CoreFileSize int64
+	// Limit of the process's resident set in pages.
+	ResidentSet int64
+	// Maximum number of processes that can be created for the real user ID of
+	// the calling process.
+	Processes int64
+	// Value one greater than the maximum file descriptor number that can be
+	// opened by this process.
+	OpenFiles int64
+	// Maximum number of bytes of memory that may be locked into RAM.
+	LockedMemory int64
+	// Maximum size of the process's virtual memory address space in bytes.
+	AddressSpace int64
+	// Limit on the combined number of flock(2) locks and fcntl(2) leases that
+	// this process may establish.
+	FileLocks int64
+	// Limit of signals that may be queued for the real user ID of the calling
+	// process.
+	PendingSignals int64
+	// Limit on the number of bytes that can be allocated for POSIX message
+	// queues for the real user ID of the calling process.
+	MsqqueueSize int64
+	// Limit of the nice priority set using setpriority(2) or nice(2).
+	NicePriority int64
+	// Limit of the real-time priority set using sched_setscheduler(2) or
+	// sched_setparam(2).
+	RealtimePriority int64
+	// Limit (in microseconds) on the amount of CPU time that a process
+	// scheduled under a real-time scheduling policy may consume without making
+	// a blocking system call.
+	RealtimeTimeout int64
+}
+
+const (
+	limitsFields    = 3
+	limitsUnlimited = "unlimited"
+)
+
+var (
+	limitsDelimiter = regexp.MustCompile("  +")
+)
+
+// NewLimits returns the current soft limits of the process.
+func (p Proc) NewLimits() (ProcLimits, error) {
+	f, err := os.Open(p.path("limits"))
+	if err != nil {
+		return ProcLimits{}, err
+	}
+	defer f.Close()
+
+	var (
+		l = ProcLimits{}
+		s = bufio.NewScanner(f)
+	)
+	for s.Scan() {
+		fields := limitsDelimiter.Split(s.Text(), limitsFields)
+		if len(fields) != limitsFields {
+			return ProcLimits{}, fmt.Errorf(
+				"couldn't parse %s line %s", f.Name(), s.Text())
+		}
+
+		switch fields[0] {
+		case "Max cpu time":
+			l.CPUTime, err = parseInt(fields[1])
+		case "Max file size":
+			l.FileSize, err = parseInt(fields[1])
+		case "Max data size":
+			l.DataSize, err = parseInt(fields[1])
+		case "Max stack size":
+			l.StackSize, err = parseInt(fields[1])
+		case "Max core file size":
+			l.CoreFileSize, err = parseInt(fields[1])
+		case "Max resident set":
+			l.ResidentSet, err = parseInt(fields[1])
+		case "Max processes":
+			l.Processes, err = parseInt(fields[1])
+		case "Max open files":
+			l.OpenFiles, err = parseInt(fields[1])
+		case "Max locked memory":
+			l.LockedMemory, err = parseInt(fields[1])
+		case "Max address space":
+			l.AddressSpace, err = parseInt(fields[1])
+		case "Max file locks":
+			l.FileLocks, err = parseInt(fields[1])
+		case "Max pending signals":
+			l.PendingSignals, err = parseInt(fields[1])
+		case "Max msgqueue size":
+			l.MsqqueueSize, err = parseInt(fields[1])
+		case "Max nice priority":
+			l.NicePriority, err = parseInt(fields[1])
+		case "Max realtime priority":
+			l.RealtimePriority, err = parseInt(fields[1])
+		case "Max realtime timeout":
+			l.RealtimeTimeout, err = parseInt(fields[1])
+		}
+		if err != nil {
+			return ProcLimits{}, err
+		}
+	}
+
+	return l, s.Err()
+}
+
+func parseInt(s string) (int64, error) {
+	if s == limitsUnlimited {
+		return -1, nil
+	}
+	i, err := strconv.ParseInt(s, 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("couldn't parse value %s: %s", s, err)
+	}
+	return i, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/proc_ns.go b/vendor/github.com/prometheus/procfs/proc_ns.go
new file mode 100644
index 0000000000..d06c26ebad
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_ns.go
@@ -0,0 +1,68 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// Namespace represents a single namespace of a process.
+type Namespace struct {
+	Type  string // Namespace type.
+	Inode uint32 // Inode number of the namespace. If two processes are in the same namespace their inodes will match.
+}
+
+// Namespaces contains all of the namespaces that the process is contained in.
+type Namespaces map[string]Namespace
+
+// NewNamespaces reads from /proc/[pid/ns/* to get the namespaces of which the
+// process is a member.
+func (p Proc) NewNamespaces() (Namespaces, error) {
+	d, err := os.Open(p.path("ns"))
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read contents of ns dir: %v", err)
+	}
+
+	ns := make(Namespaces, len(names))
+	for _, name := range names {
+		target, err := os.Readlink(p.path("ns", name))
+		if err != nil {
+			return nil, err
+		}
+
+		fields := strings.SplitN(target, ":", 2)
+		if len(fields) != 2 {
+			return nil, fmt.Errorf("failed to parse namespace type and inode from '%v'", target)
+		}
+
+		typ := fields[0]
+		inode, err := strconv.ParseUint(strings.Trim(fields[1], "[]"), 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse inode from '%v': %v", fields[1], err)
+		}
+
+		ns[name] = Namespace{typ, uint32(inode)}
+	}
+
+	return ns, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/proc_psi.go b/vendor/github.com/prometheus/procfs/proc_psi.go
new file mode 100644
index 0000000000..4f11cdbdbe
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_psi.go
@@ -0,0 +1,110 @@
+// Copyright 2019 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+// The PSI / pressure interface is described at
+//   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/accounting/psi.txt
+// Each resource (cpu, io, memory, ...) is exposed as a single file.
+// Each file may contain up to two lines, one for "some" pressure and one for "full" pressure.
+// Each line contains several averages (over n seconds) and a total in µs.
+//
+// Example io pressure file:
+// > some avg10=0.06 avg60=0.21 avg300=0.99 total=8537362
+// > full avg10=0.00 avg60=0.13 avg300=0.96 total=8183134
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+)
+
+const lineFormat = "avg10=%f avg60=%f avg300=%f total=%d"
+
+// PSILine is a single line of values as returned by /proc/pressure/*
+// The Avg entries are averages over n seconds, as a percentage
+// The Total line is in microseconds
+type PSILine struct {
+	Avg10  float64
+	Avg60  float64
+	Avg300 float64
+	Total  uint64
+}
+
+// PSIStats represent pressure stall information from /proc/pressure/*
+// Some indicates the share of time in which at least some tasks are stalled
+// Full indicates the share of time in which all non-idle tasks are stalled simultaneously
+type PSIStats struct {
+	Some *PSILine
+	Full *PSILine
+}
+
+// NewPSIStatsForResource reads pressure stall information for the specified
+// resource. At time of writing this can be either "cpu", "memory" or "io".
+func NewPSIStatsForResource(resource string) (PSIStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return PSIStats{}, err
+	}
+
+	return fs.NewPSIStatsForResource(resource)
+}
+
+// NewPSIStatsForResource reads pressure stall information from /proc/pressure/<resource>
+func (fs FS) NewPSIStatsForResource(resource string) (PSIStats, error) {
+	file, err := os.Open(fs.Path(fmt.Sprintf("%s/%s", "pressure", resource)))
+	if err != nil {
+		return PSIStats{}, fmt.Errorf("psi_stats: unavailable for %s", resource)
+	}
+
+	defer file.Close()
+	return parsePSIStats(resource, file)
+}
+
+// parsePSIStats parses the specified file for pressure stall information
+func parsePSIStats(resource string, file io.Reader) (PSIStats, error) {
+	psiStats := PSIStats{}
+	stats, err := ioutil.ReadAll(file)
+	if err != nil {
+		return psiStats, fmt.Errorf("psi_stats: unable to read data for %s", resource)
+	}
+
+	for _, l := range strings.Split(string(stats), "\n") {
+		prefix := strings.Split(l, " ")[0]
+		switch prefix {
+		case "some":
+			psi := PSILine{}
+			_, err := fmt.Sscanf(l, fmt.Sprintf("some %s", lineFormat), &psi.Avg10, &psi.Avg60, &psi.Avg300, &psi.Total)
+			if err != nil {
+				return PSIStats{}, err
+			}
+			psiStats.Some = &psi
+		case "full":
+			psi := PSILine{}
+			_, err := fmt.Sscanf(l, fmt.Sprintf("full %s", lineFormat), &psi.Avg10, &psi.Avg60, &psi.Avg300, &psi.Total)
+			if err != nil {
+				return PSIStats{}, err
+			}
+			psiStats.Full = &psi
+		default:
+			// If we encounter a line with an unknown prefix, ignore it and move on
+			// Should new measurement types be added in the future we'll simply ignore them instead
+			// of erroring on retrieval
+			continue
+		}
+	}
+
+	return psiStats, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/proc_stat.go b/vendor/github.com/prometheus/procfs/proc_stat.go
new file mode 100644
index 0000000000..e7c626a8e8
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_stat.go
@@ -0,0 +1,188 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+// Originally, this USER_HZ value was dynamically retrieved via a sysconf call
+// which required cgo. However, that caused a lot of problems regarding
+// cross-compilation. Alternatives such as running a binary to determine the
+// value, or trying to derive it in some other way were all problematic.  After
+// much research it was determined that USER_HZ is actually hardcoded to 100 on
+// all Go-supported platforms as of the time of this writing. This is why we
+// decided to hardcode it here as well. It is not impossible that there could
+// be systems with exceptions, but they should be very exotic edge cases, and
+// in that case, the worst outcome will be two misreported metrics.
+//
+// See also the following discussions:
+//
+// - https://github.com/prometheus/node_exporter/issues/52
+// - https://github.com/prometheus/procfs/pull/2
+// - http://stackoverflow.com/questions/17410841/how-does-user-hz-solve-the-jiffy-scaling-issue
+const userHZ = 100
+
+// ProcStat provides status information about the process,
+// read from /proc/[pid]/stat.
+type ProcStat struct {
+	// The process ID.
+	PID int
+	// The filename of the executable.
+	Comm string
+	// The process state.
+	State string
+	// The PID of the parent of this process.
+	PPID int
+	// The process group ID of the process.
+	PGRP int
+	// The session ID of the process.
+	Session int
+	// The controlling terminal of the process.
+	TTY int
+	// The ID of the foreground process group of the controlling terminal of
+	// the process.
+	TPGID int
+	// The kernel flags word of the process.
+	Flags uint
+	// The number of minor faults the process has made which have not required
+	// loading a memory page from disk.
+	MinFlt uint
+	// The number of minor faults that the process's waited-for children have
+	// made.
+	CMinFlt uint
+	// The number of major faults the process has made which have required
+	// loading a memory page from disk.
+	MajFlt uint
+	// The number of major faults that the process's waited-for children have
+	// made.
+	CMajFlt uint
+	// Amount of time that this process has been scheduled in user mode,
+	// measured in clock ticks.
+	UTime uint
+	// Amount of time that this process has been scheduled in kernel mode,
+	// measured in clock ticks.
+	STime uint
+	// Amount of time that this process's waited-for children have been
+	// scheduled in user mode, measured in clock ticks.
+	CUTime uint
+	// Amount of time that this process's waited-for children have been
+	// scheduled in kernel mode, measured in clock ticks.
+	CSTime uint
+	// For processes running a real-time scheduling policy, this is the negated
+	// scheduling priority, minus one.
+	Priority int
+	// The nice value, a value in the range 19 (low priority) to -20 (high
+	// priority).
+	Nice int
+	// Number of threads in this process.
+	NumThreads int
+	// The time the process started after system boot, the value is expressed
+	// in clock ticks.
+	Starttime uint64
+	// Virtual memory size in bytes.
+	VSize uint
+	// Resident set size in pages.
+	RSS int
+
+	fs FS
+}
+
+// NewStat returns the current status information of the process.
+func (p Proc) NewStat() (ProcStat, error) {
+	f, err := os.Open(p.path("stat"))
+	if err != nil {
+		return ProcStat{}, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return ProcStat{}, err
+	}
+
+	var (
+		ignore int
+
+		s = ProcStat{PID: p.PID, fs: p.fs}
+		l = bytes.Index(data, []byte("("))
+		r = bytes.LastIndex(data, []byte(")"))
+	)
+
+	if l < 0 || r < 0 {
+		return ProcStat{}, fmt.Errorf(
+			"unexpected format, couldn't extract comm: %s",
+			data,
+		)
+	}
+
+	s.Comm = string(data[l+1 : r])
+	_, err = fmt.Fscan(
+		bytes.NewBuffer(data[r+2:]),
+		&s.State,
+		&s.PPID,
+		&s.PGRP,
+		&s.Session,
+		&s.TTY,
+		&s.TPGID,
+		&s.Flags,
+		&s.MinFlt,
+		&s.CMinFlt,
+		&s.MajFlt,
+		&s.CMajFlt,
+		&s.UTime,
+		&s.STime,
+		&s.CUTime,
+		&s.CSTime,
+		&s.Priority,
+		&s.Nice,
+		&s.NumThreads,
+		&ignore,
+		&s.Starttime,
+		&s.VSize,
+		&s.RSS,
+	)
+	if err != nil {
+		return ProcStat{}, err
+	}
+
+	return s, nil
+}
+
+// VirtualMemory returns the virtual memory size in bytes.
+func (s ProcStat) VirtualMemory() uint {
+	return s.VSize
+}
+
+// ResidentMemory returns the resident memory size in bytes.
+func (s ProcStat) ResidentMemory() int {
+	return s.RSS * os.Getpagesize()
+}
+
+// StartTime returns the unix timestamp of the process in seconds.
+func (s ProcStat) StartTime() (float64, error) {
+	stat, err := s.fs.NewStat()
+	if err != nil {
+		return 0, err
+	}
+	return float64(stat.BootTime) + (float64(s.Starttime) / userHZ), nil
+}
+
+// CPUTime returns the total CPU user and system time in seconds.
+func (s ProcStat) CPUTime() float64 {
+	return float64(s.UTime+s.STime) / userHZ
+}
diff --git a/vendor/github.com/prometheus/procfs/stat.go b/vendor/github.com/prometheus/procfs/stat.go
new file mode 100644
index 0000000000..61eb6b0e3c
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/stat.go
@@ -0,0 +1,232 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// CPUStat shows how much time the cpu spend in various stages.
+type CPUStat struct {
+	User      float64
+	Nice      float64
+	System    float64
+	Idle      float64
+	Iowait    float64
+	IRQ       float64
+	SoftIRQ   float64
+	Steal     float64
+	Guest     float64
+	GuestNice float64
+}
+
+// SoftIRQStat represent the softirq statistics as exported in the procfs stat file.
+// A nice introduction can be found at https://0xax.gitbooks.io/linux-insides/content/interrupts/interrupts-9.html
+// It is possible to get per-cpu stats by reading /proc/softirqs
+type SoftIRQStat struct {
+	Hi          uint64
+	Timer       uint64
+	NetTx       uint64
+	NetRx       uint64
+	Block       uint64
+	BlockIoPoll uint64
+	Tasklet     uint64
+	Sched       uint64
+	Hrtimer     uint64
+	Rcu         uint64
+}
+
+// Stat represents kernel/system statistics.
+type Stat struct {
+	// Boot time in seconds since the Epoch.
+	BootTime uint64
+	// Summed up cpu statistics.
+	CPUTotal CPUStat
+	// Per-CPU statistics.
+	CPU []CPUStat
+	// Number of times interrupts were handled, which contains numbered and unnumbered IRQs.
+	IRQTotal uint64
+	// Number of times a numbered IRQ was triggered.
+	IRQ []uint64
+	// Number of times a context switch happened.
+	ContextSwitches uint64
+	// Number of times a process was created.
+	ProcessCreated uint64
+	// Number of processes currently running.
+	ProcessesRunning uint64
+	// Number of processes currently blocked (waiting for IO).
+	ProcessesBlocked uint64
+	// Number of times a softirq was scheduled.
+	SoftIRQTotal uint64
+	// Detailed softirq statistics.
+	SoftIRQ SoftIRQStat
+}
+
+// NewStat returns kernel/system statistics read from /proc/stat.
+func NewStat() (Stat, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Stat{}, err
+	}
+
+	return fs.NewStat()
+}
+
+// Parse a cpu statistics line and returns the CPUStat struct plus the cpu id (or -1 for the overall sum).
+func parseCPUStat(line string) (CPUStat, int64, error) {
+	cpuStat := CPUStat{}
+	var cpu string
+
+	count, err := fmt.Sscanf(line, "%s %f %f %f %f %f %f %f %f %f %f",
+		&cpu,
+		&cpuStat.User, &cpuStat.Nice, &cpuStat.System, &cpuStat.Idle,
+		&cpuStat.Iowait, &cpuStat.IRQ, &cpuStat.SoftIRQ, &cpuStat.Steal,
+		&cpuStat.Guest, &cpuStat.GuestNice)
+
+	if err != nil && err != io.EOF {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu): %s", line, err)
+	}
+	if count == 0 {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu): 0 elements parsed", line)
+	}
+
+	cpuStat.User /= userHZ
+	cpuStat.Nice /= userHZ
+	cpuStat.System /= userHZ
+	cpuStat.Idle /= userHZ
+	cpuStat.Iowait /= userHZ
+	cpuStat.IRQ /= userHZ
+	cpuStat.SoftIRQ /= userHZ
+	cpuStat.Steal /= userHZ
+	cpuStat.Guest /= userHZ
+	cpuStat.GuestNice /= userHZ
+
+	if cpu == "cpu" {
+		return cpuStat, -1, nil
+	}
+
+	cpuID, err := strconv.ParseInt(cpu[3:], 10, 64)
+	if err != nil {
+		return CPUStat{}, -1, fmt.Errorf("couldn't parse %s (cpu/cpuid): %s", line, err)
+	}
+
+	return cpuStat, cpuID, nil
+}
+
+// Parse a softirq line.
+func parseSoftIRQStat(line string) (SoftIRQStat, uint64, error) {
+	softIRQStat := SoftIRQStat{}
+	var total uint64
+	var prefix string
+
+	_, err := fmt.Sscanf(line, "%s %d %d %d %d %d %d %d %d %d %d %d",
+		&prefix, &total,
+		&softIRQStat.Hi, &softIRQStat.Timer, &softIRQStat.NetTx, &softIRQStat.NetRx,
+		&softIRQStat.Block, &softIRQStat.BlockIoPoll,
+		&softIRQStat.Tasklet, &softIRQStat.Sched,
+		&softIRQStat.Hrtimer, &softIRQStat.Rcu)
+
+	if err != nil {
+		return SoftIRQStat{}, 0, fmt.Errorf("couldn't parse %s (softirq): %s", line, err)
+	}
+
+	return softIRQStat, total, nil
+}
+
+// NewStat returns an information about current kernel/system statistics.
+func (fs FS) NewStat() (Stat, error) {
+	// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt
+
+	f, err := os.Open(fs.Path("stat"))
+	if err != nil {
+		return Stat{}, err
+	}
+	defer f.Close()
+
+	stat := Stat{}
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			continue
+		}
+		switch {
+		case parts[0] == "btime":
+			if stat.BootTime, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (btime): %s", parts[1], err)
+			}
+		case parts[0] == "intr":
+			if stat.IRQTotal, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (intr): %s", parts[1], err)
+			}
+			numberedIRQs := parts[2:]
+			stat.IRQ = make([]uint64, len(numberedIRQs))
+			for i, count := range numberedIRQs {
+				if stat.IRQ[i], err = strconv.ParseUint(count, 10, 64); err != nil {
+					return Stat{}, fmt.Errorf("couldn't parse %s (intr%d): %s", count, i, err)
+				}
+			}
+		case parts[0] == "ctxt":
+			if stat.ContextSwitches, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (ctxt): %s", parts[1], err)
+			}
+		case parts[0] == "processes":
+			if stat.ProcessCreated, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (processes): %s", parts[1], err)
+			}
+		case parts[0] == "procs_running":
+			if stat.ProcessesRunning, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (procs_running): %s", parts[1], err)
+			}
+		case parts[0] == "procs_blocked":
+			if stat.ProcessesBlocked, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
+				return Stat{}, fmt.Errorf("couldn't parse %s (procs_blocked): %s", parts[1], err)
+			}
+		case parts[0] == "softirq":
+			softIRQStats, total, err := parseSoftIRQStat(line)
+			if err != nil {
+				return Stat{}, err
+			}
+			stat.SoftIRQTotal = total
+			stat.SoftIRQ = softIRQStats
+		case strings.HasPrefix(parts[0], "cpu"):
+			cpuStat, cpuID, err := parseCPUStat(line)
+			if err != nil {
+				return Stat{}, err
+			}
+			if cpuID == -1 {
+				stat.CPUTotal = cpuStat
+			} else {
+				for int64(len(stat.CPU)) <= cpuID {
+					stat.CPU = append(stat.CPU, CPUStat{})
+				}
+				stat.CPU[cpuID] = cpuStat
+			}
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return Stat{}, fmt.Errorf("couldn't parse %s: %s", f.Name(), err)
+	}
+
+	return stat, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/ttar b/vendor/github.com/prometheus/procfs/ttar
new file mode 100755
index 0000000000..b0171a12b5
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/ttar
@@ -0,0 +1,389 @@
+#!/usr/bin/env bash
+
+# Purpose: plain text tar format
+# Limitations: - only suitable for text files, directories, and symlinks
+#              - stores only filename, content, and mode
+#              - not designed for untrusted input
+#
+# Note: must work with bash version 3.2 (macOS)
+
+# Copyright 2017 Roger Luethi
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -o errexit -o nounset
+
+# Sanitize environment (for instance, standard sorting of glob matches)
+export LC_ALL=C
+
+path=""
+CMD=""
+ARG_STRING="$*"
+
+#------------------------------------------------------------------------------
+# Not all sed implementations can work on null bytes. In order to make ttar
+# work out of the box on macOS, use Python as a stream editor.
+
+USE_PYTHON=0
+
+PYTHON_CREATE_FILTER=$(cat << 'PCF'
+#!/usr/bin/env python
+
+import re
+import sys
+
+for line in sys.stdin:
+    line = re.sub(r'EOF', r'\EOF', line)
+    line = re.sub(r'NULLBYTE', r'\NULLBYTE', line)
+    line = re.sub('\x00', r'NULLBYTE', line)
+    sys.stdout.write(line)
+PCF
+)
+
+PYTHON_EXTRACT_FILTER=$(cat << 'PEF'
+#!/usr/bin/env python
+
+import re
+import sys
+
+for line in sys.stdin:
+    line = re.sub(r'(?<!\\)NULLBYTE', '\x00', line)
+    line = re.sub(r'\\NULLBYTE', 'NULLBYTE', line)
+    line = re.sub(r'([^\\])EOF', r'\1', line)
+    line = re.sub(r'\\EOF', 'EOF', line)
+    sys.stdout.write(line)
+PEF
+)
+
+function test_environment {
+    if [[ "$(echo "a" | sed 's/a/\x0/' | wc -c)" -ne 2 ]]; then
+        echo "WARNING sed unable to handle null bytes, using Python (slow)."
+        if ! which python >/dev/null; then
+            echo "ERROR Python not found. Aborting."
+            exit 2
+        fi
+        USE_PYTHON=1
+    fi
+}
+
+#------------------------------------------------------------------------------
+
+function usage {
+    bname=$(basename "$0")
+    cat << USAGE
+Usage:   $bname [-C <DIR>] -c -f <ARCHIVE> <FILE...> (create archive)
+         $bname            -t -f <ARCHIVE>           (list archive contents)
+         $bname [-C <DIR>] -x -f <ARCHIVE>           (extract archive)
+
+Options:
+         -C <DIR>                                    (change directory)
+         -v                                          (verbose)
+
+Example: Change to sysfs directory, create ttar file from fixtures directory
+         $bname -C sysfs -c -f sysfs/fixtures.ttar fixtures/
+USAGE
+exit "$1"
+}
+
+function vecho {
+    if [ "${VERBOSE:-}" == "yes" ]; then
+        echo >&7 "$@"
+    fi
+}
+
+function set_cmd {
+    if [ -n "$CMD" ]; then
+        echo "ERROR: more than one command given"
+        echo
+        usage 2
+    fi
+    CMD=$1
+}
+
+unset VERBOSE
+
+while getopts :cf:htxvC: opt; do
+    case $opt in
+        c)
+            set_cmd "create"
+            ;;
+        f)
+            ARCHIVE=$OPTARG
+            ;;
+        h)
+            usage 0
+            ;;
+        t)
+            set_cmd "list"
+            ;;
+        x)
+            set_cmd "extract"
+            ;;
+        v)
+            VERBOSE=yes
+            exec 7>&1
+            ;;
+        C)
+            CDIR=$OPTARG
+            ;;
+        *)
+            echo >&2 "ERROR: invalid option -$OPTARG"
+            echo
+            usage 1
+            ;;
+    esac
+done
+
+# Remove processed options from arguments
+shift $(( OPTIND - 1 ));
+
+if [ "${CMD:-}" == "" ]; then
+    echo >&2 "ERROR: no command given"
+    echo
+    usage 1
+elif [ "${ARCHIVE:-}" == "" ]; then
+    echo >&2 "ERROR: no archive name given"
+    echo
+    usage 1
+fi
+
+function list {
+    local path=""
+    local size=0
+    local line_no=0
+    local ttar_file=$1
+    if [ -n "${2:-}" ]; then
+        echo >&2 "ERROR: too many arguments."
+        echo
+        usage 1
+    fi
+    if [ ! -e "$ttar_file" ]; then
+        echo >&2 "ERROR: file not found ($ttar_file)"
+        echo
+        usage 1
+    fi
+    while read -r line; do
+        line_no=$(( line_no + 1 ))
+        if [ $size -gt 0 ]; then
+            size=$(( size - 1 ))
+            continue
+        fi
+        if [[ $line =~ ^Path:\ (.*)$ ]]; then
+            path=${BASH_REMATCH[1]}
+        elif [[ $line =~ ^Lines:\ (.*)$ ]]; then
+            size=${BASH_REMATCH[1]}
+            echo "$path"
+        elif [[ $line =~ ^Directory:\ (.*)$ ]]; then
+            path=${BASH_REMATCH[1]}
+            echo "$path/"
+        elif [[ $line =~ ^SymlinkTo:\ (.*)$ ]]; then
+            echo  "$path -> ${BASH_REMATCH[1]}"
+        fi
+    done < "$ttar_file"
+}
+
+function extract {
+    local path=""
+    local size=0
+    local line_no=0
+    local ttar_file=$1
+    if [ -n "${2:-}" ]; then
+        echo >&2 "ERROR: too many arguments."
+        echo
+        usage 1
+    fi
+    if [ ! -e "$ttar_file" ]; then
+        echo >&2 "ERROR: file not found ($ttar_file)"
+        echo
+        usage 1
+    fi
+    while IFS= read -r line; do
+        line_no=$(( line_no + 1 ))
+        local eof_without_newline
+        if [ "$size" -gt 0 ]; then
+            if [[ "$line" =~ [^\\]EOF ]]; then
+                # An EOF not preceeded by a backslash indicates that the line
+                # does not end with a newline
+                eof_without_newline=1
+            else
+                eof_without_newline=0
+            fi
+            # Replace NULLBYTE with null byte if at beginning of line
+            # Replace NULLBYTE with null byte unless preceeded by backslash
+            # Remove one backslash in front of NULLBYTE (if any)
+            # Remove EOF unless preceeded by backslash
+            # Remove one backslash in front of EOF
+            if [ $USE_PYTHON -eq 1 ]; then
+                echo -n "$line" | python -c "$PYTHON_EXTRACT_FILTER" >> "$path"
+            else
+                # The repeated pattern makes up for sed's lack of negative
+                # lookbehind assertions (for consecutive null bytes).
+                echo -n "$line" | \
+                    sed -e 's/^NULLBYTE/\x0/g;
+                            s/\([^\\]\)NULLBYTE/\1\x0/g;
+                            s/\([^\\]\)NULLBYTE/\1\x0/g;
+                            s/\\NULLBYTE/NULLBYTE/g;
+                            s/\([^\\]\)EOF/\1/g;
+                            s/\\EOF/EOF/g;
+                    ' >> "$path"
+            fi
+            if [[ "$eof_without_newline" -eq 0 ]]; then
+                echo >> "$path"
+            fi
+            size=$(( size - 1 ))
+            continue
+        fi
+        if [[ $line =~ ^Path:\ (.*)$ ]]; then
+            path=${BASH_REMATCH[1]}
+            if [ -e "$path" ] || [ -L "$path" ]; then
+                rm "$path"
+            fi
+        elif [[ $line =~ ^Lines:\ (.*)$ ]]; then
+            size=${BASH_REMATCH[1]}
+            # Create file even if it is zero-length.
+            touch "$path"
+            vecho "    $path"
+        elif [[ $line =~ ^Mode:\ (.*)$ ]]; then
+            mode=${BASH_REMATCH[1]}
+            chmod "$mode" "$path"
+            vecho "$mode"
+        elif [[ $line =~ ^Directory:\ (.*)$ ]]; then
+            path=${BASH_REMATCH[1]}
+            mkdir -p "$path"
+            vecho "    $path/"
+        elif [[ $line =~ ^SymlinkTo:\ (.*)$ ]]; then
+            ln -s "${BASH_REMATCH[1]}" "$path"
+            vecho "    $path -> ${BASH_REMATCH[1]}"
+        elif [[ $line =~ ^# ]]; then
+            # Ignore comments between files
+            continue
+        else
+            echo >&2 "ERROR: Unknown keyword on line $line_no: $line"
+            exit 1
+        fi
+    done < "$ttar_file"
+}
+
+function div {
+    echo "# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -" \
+         "- - - - - -"
+}
+
+function get_mode {
+    local mfile=$1
+    if [ -z "${STAT_OPTION:-}" ]; then
+        if stat -c '%a' "$mfile" >/dev/null 2>&1; then
+            # GNU stat
+            STAT_OPTION='-c'
+            STAT_FORMAT='%a'
+        else
+            # BSD stat
+            STAT_OPTION='-f'
+            # Octal output, user/group/other (omit file type, sticky bit)
+            STAT_FORMAT='%OLp'
+        fi
+    fi
+    stat "${STAT_OPTION}" "${STAT_FORMAT}" "$mfile"
+}
+
+function _create {
+    shopt -s nullglob
+    local mode
+    local eof_without_newline
+    while (( "$#" )); do
+        file=$1
+        if [ -L "$file" ]; then
+            echo "Path: $file"
+            symlinkTo=$(readlink "$file")
+            echo "SymlinkTo: $symlinkTo"
+            vecho "    $file -> $symlinkTo"
+            div
+        elif [ -d "$file" ]; then
+            # Strip trailing slash (if there is one)
+            file=${file%/}
+            echo "Directory: $file"
+            mode=$(get_mode "$file")
+            echo "Mode: $mode"
+            vecho "$mode $file/"
+            div
+            # Find all files and dirs, including hidden/dot files
+            for x in "$file/"{*,.[^.]*}; do
+                _create "$x"
+            done
+        elif [ -f "$file" ]; then
+            echo "Path: $file"
+            lines=$(wc -l "$file"|awk '{print $1}')
+            eof_without_newline=0
+            if [[ "$(wc -c "$file"|awk '{print $1}')" -gt 0 ]] && \
+                    [[ "$(tail -c 1 "$file" | wc -l)" -eq 0 ]]; then
+                eof_without_newline=1
+                lines=$((lines+1))
+            fi
+            echo "Lines: $lines"
+            # Add backslash in front of EOF
+            # Add backslash in front of NULLBYTE
+            # Replace null byte with NULLBYTE
+            if [ $USE_PYTHON -eq 1 ]; then
+                < "$file" python -c "$PYTHON_CREATE_FILTER"
+            else
+                < "$file" \
+                    sed 's/EOF/\\EOF/g;
+                         s/NULLBYTE/\\NULLBYTE/g;
+                         s/\x0/NULLBYTE/g;
+                    '
+            fi
+            if [[ "$eof_without_newline" -eq 1 ]]; then
+                # Finish line with EOF to indicate that the original line did
+                # not end with a linefeed
+                echo "EOF"
+            fi
+            mode=$(get_mode "$file")
+            echo "Mode: $mode"
+            vecho "$mode $file"
+            div
+        else
+            echo >&2 "ERROR: file not found ($file in $(pwd))"
+            exit 2
+        fi
+        shift
+    done
+}
+
+function create {
+    ttar_file=$1
+    shift
+    if [ -z "${1:-}" ]; then
+        echo >&2 "ERROR: missing arguments."
+        echo
+        usage 1
+    fi
+    if [ -e "$ttar_file" ]; then
+        rm "$ttar_file"
+    fi
+    exec > "$ttar_file"
+    echo "# Archive created by ttar $ARG_STRING"
+    _create "$@"
+}
+
+test_environment
+
+if [ -n "${CDIR:-}" ]; then
+    if [[ "$ARCHIVE" != /* ]]; then
+        # Relative path: preserve the archive's location before changing
+        # directory
+        ARCHIVE="$(pwd)/$ARCHIVE"
+    fi
+    cd "$CDIR"
+fi
+
+"$CMD" "$ARCHIVE" "$@"
diff --git a/vendor/github.com/prometheus/procfs/xfrm.go b/vendor/github.com/prometheus/procfs/xfrm.go
new file mode 100644
index 0000000000..8f1508f0fd
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/xfrm.go
@@ -0,0 +1,187 @@
+// Copyright 2017 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// XfrmStat models the contents of /proc/net/xfrm_stat.
+type XfrmStat struct {
+	// All errors which are not matched by other
+	XfrmInError int
+	// No buffer is left
+	XfrmInBufferError int
+	// Header Error
+	XfrmInHdrError int
+	// No state found
+	// i.e. either inbound SPI, address, or IPSEC protocol at SA is wrong
+	XfrmInNoStates int
+	// Transformation protocol specific error
+	// e.g. SA Key is wrong
+	XfrmInStateProtoError int
+	// Transformation mode specific error
+	XfrmInStateModeError int
+	// Sequence error
+	// e.g. sequence number is out of window
+	XfrmInStateSeqError int
+	// State is expired
+	XfrmInStateExpired int
+	// State has mismatch option
+	// e.g. UDP encapsulation type is mismatched
+	XfrmInStateMismatch int
+	// State is invalid
+	XfrmInStateInvalid int
+	// No matching template for states
+	// e.g. Inbound SAs are correct but SP rule is wrong
+	XfrmInTmplMismatch int
+	// No policy is found for states
+	// e.g. Inbound SAs are correct but no SP is found
+	XfrmInNoPols int
+	// Policy discards
+	XfrmInPolBlock int
+	// Policy error
+	XfrmInPolError int
+	// All errors which are not matched by others
+	XfrmOutError int
+	// Bundle generation error
+	XfrmOutBundleGenError int
+	// Bundle check error
+	XfrmOutBundleCheckError int
+	// No state was found
+	XfrmOutNoStates int
+	// Transformation protocol specific error
+	XfrmOutStateProtoError int
+	// Transportation mode specific error
+	XfrmOutStateModeError int
+	// Sequence error
+	// i.e sequence number overflow
+	XfrmOutStateSeqError int
+	// State is expired
+	XfrmOutStateExpired int
+	// Policy discads
+	XfrmOutPolBlock int
+	// Policy is dead
+	XfrmOutPolDead int
+	// Policy Error
+	XfrmOutPolError     int
+	XfrmFwdHdrError     int
+	XfrmOutStateInvalid int
+	XfrmAcquireError    int
+}
+
+// NewXfrmStat reads the xfrm_stat statistics.
+func NewXfrmStat() (XfrmStat, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return XfrmStat{}, err
+	}
+
+	return fs.NewXfrmStat()
+}
+
+// NewXfrmStat reads the xfrm_stat statistics from the 'proc' filesystem.
+func (fs FS) NewXfrmStat() (XfrmStat, error) {
+	file, err := os.Open(fs.Path("net/xfrm_stat"))
+	if err != nil {
+		return XfrmStat{}, err
+	}
+	defer file.Close()
+
+	var (
+		x = XfrmStat{}
+		s = bufio.NewScanner(file)
+	)
+
+	for s.Scan() {
+		fields := strings.Fields(s.Text())
+
+		if len(fields) != 2 {
+			return XfrmStat{}, fmt.Errorf(
+				"couldn't parse %s line %s", file.Name(), s.Text())
+		}
+
+		name := fields[0]
+		value, err := strconv.Atoi(fields[1])
+		if err != nil {
+			return XfrmStat{}, err
+		}
+
+		switch name {
+		case "XfrmInError":
+			x.XfrmInError = value
+		case "XfrmInBufferError":
+			x.XfrmInBufferError = value
+		case "XfrmInHdrError":
+			x.XfrmInHdrError = value
+		case "XfrmInNoStates":
+			x.XfrmInNoStates = value
+		case "XfrmInStateProtoError":
+			x.XfrmInStateProtoError = value
+		case "XfrmInStateModeError":
+			x.XfrmInStateModeError = value
+		case "XfrmInStateSeqError":
+			x.XfrmInStateSeqError = value
+		case "XfrmInStateExpired":
+			x.XfrmInStateExpired = value
+		case "XfrmInStateInvalid":
+			x.XfrmInStateInvalid = value
+		case "XfrmInTmplMismatch":
+			x.XfrmInTmplMismatch = value
+		case "XfrmInNoPols":
+			x.XfrmInNoPols = value
+		case "XfrmInPolBlock":
+			x.XfrmInPolBlock = value
+		case "XfrmInPolError":
+			x.XfrmInPolError = value
+		case "XfrmOutError":
+			x.XfrmOutError = value
+		case "XfrmInStateMismatch":
+			x.XfrmInStateMismatch = value
+		case "XfrmOutBundleGenError":
+			x.XfrmOutBundleGenError = value
+		case "XfrmOutBundleCheckError":
+			x.XfrmOutBundleCheckError = value
+		case "XfrmOutNoStates":
+			x.XfrmOutNoStates = value
+		case "XfrmOutStateProtoError":
+			x.XfrmOutStateProtoError = value
+		case "XfrmOutStateModeError":
+			x.XfrmOutStateModeError = value
+		case "XfrmOutStateSeqError":
+			x.XfrmOutStateSeqError = value
+		case "XfrmOutStateExpired":
+			x.XfrmOutStateExpired = value
+		case "XfrmOutPolBlock":
+			x.XfrmOutPolBlock = value
+		case "XfrmOutPolDead":
+			x.XfrmOutPolDead = value
+		case "XfrmOutPolError":
+			x.XfrmOutPolError = value
+		case "XfrmFwdHdrError":
+			x.XfrmFwdHdrError = value
+		case "XfrmOutStateInvalid":
+			x.XfrmOutStateInvalid = value
+		case "XfrmAcquireError":
+			x.XfrmAcquireError = value
+		}
+
+	}
+
+	return x, s.Err()
+}
diff --git a/vendor/github.com/prometheus/procfs/xfs/parse.go b/vendor/github.com/prometheus/procfs/xfs/parse.go
new file mode 100644
index 0000000000..b3d8634df3
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/xfs/parse.go
@@ -0,0 +1,330 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package xfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseStats parses a Stats from an input io.Reader, using the format
+// found in /proc/fs/xfs/stat.
+func ParseStats(r io.Reader) (*Stats, error) {
+	const (
+		// Fields parsed into stats structures.
+		fieldExtentAlloc = "extent_alloc"
+		fieldAbt         = "abt"
+		fieldBlkMap      = "blk_map"
+		fieldBmbt        = "bmbt"
+		fieldDir         = "dir"
+		fieldTrans       = "trans"
+		fieldIg          = "ig"
+		fieldLog         = "log"
+		fieldRw          = "rw"
+		fieldAttr        = "attr"
+		fieldIcluster    = "icluster"
+		fieldVnodes      = "vnodes"
+		fieldBuf         = "buf"
+		fieldXpc         = "xpc"
+
+		// Unimplemented at this time due to lack of documentation.
+		// fieldPushAil = "push_ail"
+		// fieldXstrat  = "xstrat"
+		// fieldAbtb2   = "abtb2"
+		// fieldAbtc2   = "abtc2"
+		// fieldBmbt2   = "bmbt2"
+		// fieldIbt2    = "ibt2"
+		// fieldFibt2   = "fibt2"
+		// fieldQm      = "qm"
+		// fieldDebug   = "debug"
+	)
+
+	var xfss Stats
+
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		// Expect at least a string label and a single integer value, ex:
+		//   - abt 0
+		//   - rw 1 2
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) < 2 {
+			continue
+		}
+		label := ss[0]
+
+		// Extended precision counters are uint64 values.
+		if label == fieldXpc {
+			us, err := util.ParseUint64s(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			xfss.ExtendedPrecision, err = extendedPrecisionStats(us)
+			if err != nil {
+				return nil, err
+			}
+
+			continue
+		}
+
+		// All other counters are uint32 values.
+		us, err := util.ParseUint32s(ss[1:])
+		if err != nil {
+			return nil, err
+		}
+
+		switch label {
+		case fieldExtentAlloc:
+			xfss.ExtentAllocation, err = extentAllocationStats(us)
+		case fieldAbt:
+			xfss.AllocationBTree, err = btreeStats(us)
+		case fieldBlkMap:
+			xfss.BlockMapping, err = blockMappingStats(us)
+		case fieldBmbt:
+			xfss.BlockMapBTree, err = btreeStats(us)
+		case fieldDir:
+			xfss.DirectoryOperation, err = directoryOperationStats(us)
+		case fieldTrans:
+			xfss.Transaction, err = transactionStats(us)
+		case fieldIg:
+			xfss.InodeOperation, err = inodeOperationStats(us)
+		case fieldLog:
+			xfss.LogOperation, err = logOperationStats(us)
+		case fieldRw:
+			xfss.ReadWrite, err = readWriteStats(us)
+		case fieldAttr:
+			xfss.AttributeOperation, err = attributeOperationStats(us)
+		case fieldIcluster:
+			xfss.InodeClustering, err = inodeClusteringStats(us)
+		case fieldVnodes:
+			xfss.Vnode, err = vnodeStats(us)
+		case fieldBuf:
+			xfss.Buffer, err = bufferStats(us)
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &xfss, s.Err()
+}
+
+// extentAllocationStats builds an ExtentAllocationStats from a slice of uint32s.
+func extentAllocationStats(us []uint32) (ExtentAllocationStats, error) {
+	if l := len(us); l != 4 {
+		return ExtentAllocationStats{}, fmt.Errorf("incorrect number of values for XFS extent allocation stats: %d", l)
+	}
+
+	return ExtentAllocationStats{
+		ExtentsAllocated: us[0],
+		BlocksAllocated:  us[1],
+		ExtentsFreed:     us[2],
+		BlocksFreed:      us[3],
+	}, nil
+}
+
+// btreeStats builds a BTreeStats from a slice of uint32s.
+func btreeStats(us []uint32) (BTreeStats, error) {
+	if l := len(us); l != 4 {
+		return BTreeStats{}, fmt.Errorf("incorrect number of values for XFS btree stats: %d", l)
+	}
+
+	return BTreeStats{
+		Lookups:         us[0],
+		Compares:        us[1],
+		RecordsInserted: us[2],
+		RecordsDeleted:  us[3],
+	}, nil
+}
+
+// BlockMappingStat builds a BlockMappingStats from a slice of uint32s.
+func blockMappingStats(us []uint32) (BlockMappingStats, error) {
+	if l := len(us); l != 7 {
+		return BlockMappingStats{}, fmt.Errorf("incorrect number of values for XFS block mapping stats: %d", l)
+	}
+
+	return BlockMappingStats{
+		Reads:                us[0],
+		Writes:               us[1],
+		Unmaps:               us[2],
+		ExtentListInsertions: us[3],
+		ExtentListDeletions:  us[4],
+		ExtentListLookups:    us[5],
+		ExtentListCompares:   us[6],
+	}, nil
+}
+
+// DirectoryOperationStats builds a DirectoryOperationStats from a slice of uint32s.
+func directoryOperationStats(us []uint32) (DirectoryOperationStats, error) {
+	if l := len(us); l != 4 {
+		return DirectoryOperationStats{}, fmt.Errorf("incorrect number of values for XFS directory operation stats: %d", l)
+	}
+
+	return DirectoryOperationStats{
+		Lookups:  us[0],
+		Creates:  us[1],
+		Removes:  us[2],
+		Getdents: us[3],
+	}, nil
+}
+
+// TransactionStats builds a TransactionStats from a slice of uint32s.
+func transactionStats(us []uint32) (TransactionStats, error) {
+	if l := len(us); l != 3 {
+		return TransactionStats{}, fmt.Errorf("incorrect number of values for XFS transaction stats: %d", l)
+	}
+
+	return TransactionStats{
+		Sync:  us[0],
+		Async: us[1],
+		Empty: us[2],
+	}, nil
+}
+
+// InodeOperationStats builds an InodeOperationStats from a slice of uint32s.
+func inodeOperationStats(us []uint32) (InodeOperationStats, error) {
+	if l := len(us); l != 7 {
+		return InodeOperationStats{}, fmt.Errorf("incorrect number of values for XFS inode operation stats: %d", l)
+	}
+
+	return InodeOperationStats{
+		Attempts:        us[0],
+		Found:           us[1],
+		Recycle:         us[2],
+		Missed:          us[3],
+		Duplicate:       us[4],
+		Reclaims:        us[5],
+		AttributeChange: us[6],
+	}, nil
+}
+
+// LogOperationStats builds a LogOperationStats from a slice of uint32s.
+func logOperationStats(us []uint32) (LogOperationStats, error) {
+	if l := len(us); l != 5 {
+		return LogOperationStats{}, fmt.Errorf("incorrect number of values for XFS log operation stats: %d", l)
+	}
+
+	return LogOperationStats{
+		Writes:            us[0],
+		Blocks:            us[1],
+		NoInternalBuffers: us[2],
+		Force:             us[3],
+		ForceSleep:        us[4],
+	}, nil
+}
+
+// ReadWriteStats builds a ReadWriteStats from a slice of uint32s.
+func readWriteStats(us []uint32) (ReadWriteStats, error) {
+	if l := len(us); l != 2 {
+		return ReadWriteStats{}, fmt.Errorf("incorrect number of values for XFS read write stats: %d", l)
+	}
+
+	return ReadWriteStats{
+		Read:  us[0],
+		Write: us[1],
+	}, nil
+}
+
+// AttributeOperationStats builds an AttributeOperationStats from a slice of uint32s.
+func attributeOperationStats(us []uint32) (AttributeOperationStats, error) {
+	if l := len(us); l != 4 {
+		return AttributeOperationStats{}, fmt.Errorf("incorrect number of values for XFS attribute operation stats: %d", l)
+	}
+
+	return AttributeOperationStats{
+		Get:    us[0],
+		Set:    us[1],
+		Remove: us[2],
+		List:   us[3],
+	}, nil
+}
+
+// InodeClusteringStats builds an InodeClusteringStats from a slice of uint32s.
+func inodeClusteringStats(us []uint32) (InodeClusteringStats, error) {
+	if l := len(us); l != 3 {
+		return InodeClusteringStats{}, fmt.Errorf("incorrect number of values for XFS inode clustering stats: %d", l)
+	}
+
+	return InodeClusteringStats{
+		Iflush:     us[0],
+		Flush:      us[1],
+		FlushInode: us[2],
+	}, nil
+}
+
+// VnodeStats builds a VnodeStats from a slice of uint32s.
+func vnodeStats(us []uint32) (VnodeStats, error) {
+	// The attribute "Free" appears to not be available on older XFS
+	// stats versions.  Therefore, 7 or 8 elements may appear in
+	// this slice.
+	l := len(us)
+	if l != 7 && l != 8 {
+		return VnodeStats{}, fmt.Errorf("incorrect number of values for XFS vnode stats: %d", l)
+	}
+
+	s := VnodeStats{
+		Active:   us[0],
+		Allocate: us[1],
+		Get:      us[2],
+		Hold:     us[3],
+		Release:  us[4],
+		Reclaim:  us[5],
+		Remove:   us[6],
+	}
+
+	// Skip adding free, unless it is present. The zero value will
+	// be used in place of an actual count.
+	if l == 7 {
+		return s, nil
+	}
+
+	s.Free = us[7]
+	return s, nil
+}
+
+// BufferStats builds a BufferStats from a slice of uint32s.
+func bufferStats(us []uint32) (BufferStats, error) {
+	if l := len(us); l != 9 {
+		return BufferStats{}, fmt.Errorf("incorrect number of values for XFS buffer stats: %d", l)
+	}
+
+	return BufferStats{
+		Get:             us[0],
+		Create:          us[1],
+		GetLocked:       us[2],
+		GetLockedWaited: us[3],
+		BusyLocked:      us[4],
+		MissLocked:      us[5],
+		PageRetries:     us[6],
+		PageFound:       us[7],
+		GetRead:         us[8],
+	}, nil
+}
+
+// ExtendedPrecisionStats builds an ExtendedPrecisionStats from a slice of uint32s.
+func extendedPrecisionStats(us []uint64) (ExtendedPrecisionStats, error) {
+	if l := len(us); l != 3 {
+		return ExtendedPrecisionStats{}, fmt.Errorf("incorrect number of values for XFS extended precision stats: %d", l)
+	}
+
+	return ExtendedPrecisionStats{
+		FlushBytes: us[0],
+		WriteBytes: us[1],
+		ReadBytes:  us[2],
+	}, nil
+}
diff --git a/vendor/github.com/prometheus/procfs/xfs/xfs.go b/vendor/github.com/prometheus/procfs/xfs/xfs.go
new file mode 100644
index 0000000000..d86794b7ca
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/xfs/xfs.go
@@ -0,0 +1,163 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package xfs provides access to statistics exposed by the XFS filesystem.
+package xfs
+
+// Stats contains XFS filesystem runtime statistics, parsed from
+// /proc/fs/xfs/stat.
+//
+// The names and meanings of each statistic were taken from
+// http://xfs.org/index.php/Runtime_Stats and xfs_stats.h in the Linux
+// kernel source. Most counters are uint32s (same data types used in
+// xfs_stats.h), but some of the "extended precision stats" are uint64s.
+type Stats struct {
+	// The name of the filesystem used to source these statistics.
+	// If empty, this indicates aggregated statistics for all XFS
+	// filesystems on the host.
+	Name string
+
+	ExtentAllocation   ExtentAllocationStats
+	AllocationBTree    BTreeStats
+	BlockMapping       BlockMappingStats
+	BlockMapBTree      BTreeStats
+	DirectoryOperation DirectoryOperationStats
+	Transaction        TransactionStats
+	InodeOperation     InodeOperationStats
+	LogOperation       LogOperationStats
+	ReadWrite          ReadWriteStats
+	AttributeOperation AttributeOperationStats
+	InodeClustering    InodeClusteringStats
+	Vnode              VnodeStats
+	Buffer             BufferStats
+	ExtendedPrecision  ExtendedPrecisionStats
+}
+
+// ExtentAllocationStats contains statistics regarding XFS extent allocations.
+type ExtentAllocationStats struct {
+	ExtentsAllocated uint32
+	BlocksAllocated  uint32
+	ExtentsFreed     uint32
+	BlocksFreed      uint32
+}
+
+// BTreeStats contains statistics regarding an XFS internal B-tree.
+type BTreeStats struct {
+	Lookups         uint32
+	Compares        uint32
+	RecordsInserted uint32
+	RecordsDeleted  uint32
+}
+
+// BlockMappingStats contains statistics regarding XFS block maps.
+type BlockMappingStats struct {
+	Reads                uint32
+	Writes               uint32
+	Unmaps               uint32
+	ExtentListInsertions uint32
+	ExtentListDeletions  uint32
+	ExtentListLookups    uint32
+	ExtentListCompares   uint32
+}
+
+// DirectoryOperationStats contains statistics regarding XFS directory entries.
+type DirectoryOperationStats struct {
+	Lookups  uint32
+	Creates  uint32
+	Removes  uint32
+	Getdents uint32
+}
+
+// TransactionStats contains statistics regarding XFS metadata transactions.
+type TransactionStats struct {
+	Sync  uint32
+	Async uint32
+	Empty uint32
+}
+
+// InodeOperationStats contains statistics regarding XFS inode operations.
+type InodeOperationStats struct {
+	Attempts        uint32
+	Found           uint32
+	Recycle         uint32
+	Missed          uint32
+	Duplicate       uint32
+	Reclaims        uint32
+	AttributeChange uint32
+}
+
+// LogOperationStats contains statistics regarding the XFS log buffer.
+type LogOperationStats struct {
+	Writes            uint32
+	Blocks            uint32
+	NoInternalBuffers uint32
+	Force             uint32
+	ForceSleep        uint32
+}
+
+// ReadWriteStats contains statistics regarding the number of read and write
+// system calls for XFS filesystems.
+type ReadWriteStats struct {
+	Read  uint32
+	Write uint32
+}
+
+// AttributeOperationStats contains statistics regarding manipulation of
+// XFS extended file attributes.
+type AttributeOperationStats struct {
+	Get    uint32
+	Set    uint32
+	Remove uint32
+	List   uint32
+}
+
+// InodeClusteringStats contains statistics regarding XFS inode clustering
+// operations.
+type InodeClusteringStats struct {
+	Iflush     uint32
+	Flush      uint32
+	FlushInode uint32
+}
+
+// VnodeStats contains statistics regarding XFS vnode operations.
+type VnodeStats struct {
+	Active   uint32
+	Allocate uint32
+	Get      uint32
+	Hold     uint32
+	Release  uint32
+	Reclaim  uint32
+	Remove   uint32
+	Free     uint32
+}
+
+// BufferStats contains statistics regarding XFS read/write I/O buffers.
+type BufferStats struct {
+	Get             uint32
+	Create          uint32
+	GetLocked       uint32
+	GetLockedWaited uint32
+	BusyLocked      uint32
+	MissLocked      uint32
+	PageRetries     uint32
+	PageFound       uint32
+	GetRead         uint32
+}
+
+// ExtendedPrecisionStats contains high precision counters used to track the
+// total number of bytes read, written, or flushed, during XFS operations.
+type ExtendedPrecisionStats struct {
+	FlushBytes uint64
+	WriteBytes uint64
+	ReadBytes  uint64
+}