Add ConfigMap name to values.yaml and allow the option to specify the leader election lock name

cmd/nginx-ingress/main.go

@@ -84,6 +84,9 @@ The external address of the service is used when reporting the status of Ingress
 	leaderElectionEnabled = flag.Bool("enable-leader-election", false,
 		"Enable Leader election to avoid multiple replicas of the controller reporting the status of Ingress resources -- only one replica will report status. See -report-ingress-status flag.")
 
+	leaderElectionLockName = flag.String("leader-election-lock-name", "nginx-ingress-leader-election",
+		`Specifies the name of the ConfigMap, within the same namespace as the controller, used as the lock for leader election. Requires -enable-leader-election.`)
+
 	nginxStatusAllowCIDRs = flag.String("nginx-status-allow-cidrs", "127.0.0.1", `Whitelist IPv4 IP/CIDR blocks to allow access to NGINX stub_status or the NGINX Plus API. Separate multiple IP/CIDR by commas.`)
 
 	nginxStatusPort = flag.Int("nginx-status-port", 8080,
@@ -297,6 +300,7 @@ func main() {
 		ControllerNamespace:     controllerNamespace,
 		ReportIngressStatus:     *reportIngressStatus,
 		IsLeaderElectionEnabled: *leaderElectionEnabled,
+		LeaderElectionLockName:  *leaderElectionLockName,
 		WildcardTLSSecret:       *wildcardTLSSecret,
 		ConfigMaps:              *nginxConfigMaps,
 	}

deployments/helm-chart/Chart.yaml

@@ -1,5 +1,5 @@
 name: nginx-ingress
-version: 0.3.5
+version: 0.3.6
 appVersion: edge
 description: NGINX Ingress Controller
 icon: https://raw.githubusercontent.com/nginxinc/kubernetes-ingress/master/deployments/helm-chart/chart-icon.png

deployments/helm-chart/README.md

@@ -65,6 +65,7 @@ Parameter | Description | Default
 `controller.image.repository` | The image repository of the Ingress controller. | nginx/nginx-ingress
 `controller.image.tag` | The tag of the Ingress controller image. | edge
 `controller.image.pullPolicy` | The pull policy for the Ingress controller image. | IfNotPresent
+`controller.config.name` | The name of the ConfigMap used by the Ingress controller. | nginx-config
 `controller.config.entries` | The entries of the ConfigMap for customizing NGINX configuration. | {}
 `controller.defaultTLS.cert` | The base64-encoded TLS certificate for the default HTTPS server. If not specified, a pre-generated self-signed certificate is used. **Note:** It is recommended that you specify your own certificate. | A pre-generated self-signed certificate.
 `controller.defaultTLS.key` | The base64-encoded TLS key for the default HTTPS server. **Note:** If not specified, a pre-generated key is used. It is recommended that you specify your own key. | A pre-generated key.
@@ -102,6 +103,7 @@ Parameter | Description | Default
 `controller.reportIngressStatus.enable` | Update the address field in the status of Ingresses resources with an external address of the Ingress controller. You must also specify the source of the external address either through an external service via `controller.reportIngressStatus.externalService` or the `external-status-address` entry in the ConfigMap via `controller.config.entries`. **Note:** `controller.config.entries.external-status-address` takes precedence if both are set. | true
 `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
+`controller.reportIngressStatus.leaderElectionLockName` | Specifies the name of the ConfigMap, within the same namespace as the controller, used as the lock for leader election. controller.reportIngressStatus.enableLeaderElection must be set to true. | nginx-ingress-leader-election
 `rbac.create` | Configures RBAC. | true
 `prometheus.create` | Expose NGINX or NGINX Plus metrics in the Prometheus format. | false
 `prometheus.port` | Configures the port to scrape the metrics. | 9113

deployments/helm-chart/templates/controller-configmap.yaml

@@ -1,7 +1,7 @@
 apiVersion: v1
 kind: ConfigMap
 metadata:
-  name: nginx-config
+  name: {{ .Values.controller.config.name }}
   labels:
     {{- include "nginx-ingress.labels" . | nindent 4 }}
 data:

deployments/helm-chart/templates/controller-deployment.yaml

@@ -58,7 +58,7 @@ spec:
               fieldPath: metadata.name
         args:
           - -nginx-plus={{ .Values.controller.nginxplus }}
-          - -nginx-configmaps=$(POD_NAMESPACE)/nginx-config
+          - -nginx-configmaps=$(POD_NAMESPACE)/{{ .Values.controller.config.name }}
 {{- if .Values.controller.defaultTLS.secret }}
           - -default-server-tls-secret={{ .Values.controller.defaultTLS.secret }}
 {{ else }}
@@ -80,6 +80,7 @@ spec:
           - -report-ingress-status
           - -external-service={{ .Values.controller.reportIngressStatus.externalService }}
           - -enable-leader-election={{ .Values.controller.reportIngressStatus.enableLeaderElection }}
+          - -leader-election-lock-name={{ .Values.controller.reportIngressStatus.leaderElectionLockName }}
 {{- end }}
 {{- if .Values.controller.wildcardTLS.secret }}
           - -wildcard-tls-secret={{ .Values.controller.wildcardTLS.secret }}
@@ -88,4 +89,4 @@ spec:
 {{- end }}
           - -enable-prometheus-metrics={{ .Values.prometheus.create }}
           - -prometheus-metrics-listen-port={{ .Values.prometheus.port }}
-{{- end }}
+{{- end }}

deployments/helm-chart/values.yaml

@@ -25,6 +25,9 @@ controller:
     pullPolicy: IfNotPresent
 
   config:
+    ## The name of the ConfigMap used by the Ingress controller.
+    name: nginx-config
+
     ## The entries of the ConfigMap for customizing NGINX configuration.
     entries: {}
 
@@ -155,6 +158,9 @@ controller:
     ## Enable Leader election to avoid multiple replicas of the controller reporting the status of Ingress resources. controller.reportIngressStatus.enable must be set to true.
     enableLeaderElection: true
 
+    ## Specifies the name of the ConfigMap, within the same namespace as the controller, used as the lock for leader election. controller.reportIngressStatus.enableLeaderElection must be set to true.
+    leaderElectionLockName: "nginx-ingress-leader-election"
+
 rbac:
   ## Configures RBAC.
   create: true
@@ -164,4 +170,4 @@ prometheus:
   create: true
 
   ## Configures the port to scrape the metrics.
-  port: 9113
+  port: 9113

docs/cli-arguments.md

@@ -29,6 +29,8 @@ Usage of ./nginx-ingress:
   -ingress-template-path string
     	Path to the ingress NGINX configuration template for an ingress resource.
 	(default for NGINX "nginx.ingress.tmpl"; default for NGINX Plus "nginx-plus.ingress.tmpl")
+  -leader-election-lock-name
+        Specifies the name of the ConfigMap, within the same namespace as the controller, used as the lock for leader election. Requires -enable-leader-election.
   -log_backtrace_at value
     	when logging hits line file:N, emit a stack trace
   -log_dir string

docs/report-ingress-status.md

@@ -17,5 +17,6 @@ The Ingress controller must be configured to report an Ingress status:
     2. A Service of the type LoadBalancer configured with an external IP or address and specified by the `-external-service` command-line flag.
 3. If you're running multiple replicas of the Ingress controller, enable leader election with the `-enable-leader-election` flag
 to ensure that only one replica updates an Ingress status.
+4. By default, the Ingress controller will use a ConfigMap with the name `nginx-ingress-leader-election` as the lock. This can be customised via the `-leader-election-lock-name` flag.
 
 Notes: The Ingress controller does not clear the status of Ingress resources when it is being shut down.

internal/k8s/controller.go

@@ -74,6 +74,7 @@ type LoadBalancerController struct {
 	leaderElector           *leaderelection.LeaderElector
 	reportIngressStatus     bool
 	isLeaderElectionEnabled bool
+	leaderElectionLockName  string
 	resync                  time.Duration
 	namespace               string
 	controllerNamespace     string
@@ -96,6 +97,7 @@ type NewLoadBalancerControllerInput struct {
 	ControllerNamespace     string
 	ReportIngressStatus     bool
 	IsLeaderElectionEnabled bool
+	LeaderElectionLockName  string
 	WildcardTLSSecret       string
 	ConfigMaps              string
 }
@@ -111,6 +113,7 @@ func NewLoadBalancerController(input NewLoadBalancerControllerInput) *LoadBalanc
 		useIngressClassOnly:     input.UseIngressClassOnly,
 		reportIngressStatus:     input.ReportIngressStatus,
 		isLeaderElectionEnabled: input.IsLeaderElectionEnabled,
+		leaderElectionLockName:  input.LeaderElectionLockName,
 		resync:                  input.ResyncPeriod,
 		namespace:               input.Namespace,
 		controllerNamespace:     input.ControllerNamespace,
@@ -168,7 +171,7 @@ func (lbc *LoadBalancerController) UpdateManagedAndMergeableIngresses(ingresses
 // addLeaderHandler adds the handler for leader election to the controller
 func (lbc *LoadBalancerController) addLeaderHandler(leaderHandler leaderelection.LeaderCallbacks) {
 	var err error
-	lbc.leaderElector, err = newLeaderElector(lbc.client, leaderHandler, lbc.controllerNamespace)
+	lbc.leaderElector, err = newLeaderElector(lbc.client, leaderHandler, lbc.controllerNamespace, lbc.leaderElectionLockName)
 	if err != nil {
 		glog.V(3).Infof("Error starting LeaderElection: %v", err)
 	}

internal/k8s/leader.go

@@ -17,7 +17,7 @@ import (
 )
 
 // newLeaderElector creates a new LeaderElection and returns the Elector.
-func newLeaderElector(client kubernetes.Interface, callbacks leaderelection.LeaderCallbacks, namespace string) (*leaderelection.LeaderElector, error) {
+func newLeaderElector(client kubernetes.Interface, callbacks leaderelection.LeaderCallbacks, namespace string, lockName string) (*leaderelection.LeaderElector, error) {
 	podName := os.Getenv("POD_NAME")
 
 	broadcaster := record.NewBroadcaster()
@@ -27,7 +27,7 @@ func newLeaderElector(client kubernetes.Interface, callbacks leaderelection.Lead
 	recorder := broadcaster.NewRecorder(scheme.Scheme, source)
 
 	lock := resourcelock.ConfigMapLock{
-		ConfigMapMeta: metav1.ObjectMeta{Namespace: namespace, Name: "leader-election"},
+		ConfigMapMeta: metav1.ObjectMeta{Namespace: namespace, Name: lockName},
 		Client:        client.CoreV1(),
 		LockConfig: resourcelock.ResourceLockConfig{
 			Identity:      podName,