Replace prometheus client with opentelemetry instrumentation

cmd/dex/serve.go

@@ -18,13 +18,14 @@ import (
 	"github.com/AppsFlyer/go-sundheit/checks"
 	gosundheithttp "github.com/AppsFlyer/go-sundheit/http"
 	"github.com/ghodss/yaml"
-	grpcprometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
 	"github.com/oklog/run"
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/collectors"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
+	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
+	"go.opentelemetry.io/contrib/instrumentation/runtime"
+	"go.opentelemetry.io/otel/exporters/metric/prometheus"
+	"go.opentelemetry.io/otel/sdk/metric/controller/basic"
+	"go.opentelemetry.io/otel/sdk/resource"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/reflection"
@@ -100,22 +101,24 @@ func runServe(options serveOptions) error {
 	}
 
 	logger.Infof("config issuer: %s", c.Issuer)
-
-	prometheusRegistry := prometheus.NewRegistry()
-	err = prometheusRegistry.Register(collectors.NewGoCollector())
+	res, err := resource.New(
+		context.Background(),
+		resource.WithoutBuiltin(), // To avoid telemetry labels
+		// resource.WithAttributes(semconv.ServiceNameKey.String("dexidp")),
+	)
 	if err != nil {
-		return fmt.Errorf("failed to register Go runtime metrics: %v", err)
+		return fmt.Errorf("register prometheus metrics resources: %v", err)
 	}
-
-	err = prometheusRegistry.Register(collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}))
+	promExporter, err := prometheus.InstallNewPipeline(prometheus.Config{
+		// nanoseconds
+		DefaultHistogramBoundaries: []float64{1000, 3000, 6000, 10000, 25000, 50000, 100000, 1000000, 50000000},
+	}, basic.WithResource(res))
 	if err != nil {
-		return fmt.Errorf("failed to register process metrics: %v", err)
+		return fmt.Errorf("register prometheus exporter: %v", err)
 	}
 
-	grpcMetrics := grpcprometheus.NewServerMetrics()
-	err = prometheusRegistry.Register(grpcMetrics)
-	if err != nil {
-		return fmt.Errorf("failed to register gRPC server metrics: %v", err)
+	if err := runtime.Start(runtime.WithMinimumReadMemStatsInterval(time.Second)); err != nil {
+		return fmt.Errorf("register prometheus runtime metrics: %v", err)
 	}
 
 	var grpcOptions []grpc.ServerOption
@@ -159,13 +162,13 @@ func runServe(options serveOptions) error {
 			tlsConfig.ClientAuth = tls.RequireAndVerifyClientCert
 			tlsConfig.ClientCAs = cPool
 
-			// Only add metrics if client auth is enabled
+			// Only if client auth is enabled
+			// TODO(nabokihms): otelgrpc only provides tracing instrumentation
 			grpcOptions = append(grpcOptions,
-				grpc.StreamInterceptor(grpcMetrics.StreamServerInterceptor()),
-				grpc.UnaryInterceptor(grpcMetrics.UnaryServerInterceptor()),
+				grpc.StreamInterceptor(otelgrpc.StreamServerInterceptor()),
+				grpc.UnaryInterceptor(otelgrpc.UnaryServerInterceptor()),
 			)
 		}
-
 		grpcOptions = append(grpcOptions, grpc.Creds(credentials.NewTLS(&tlsConfig)))
 	}
 
@@ -270,7 +273,6 @@ func runServe(options serveOptions) error {
 		Web:                    c.Frontend,
 		Logger:                 logger,
 		Now:                    now,
-		PrometheusRegistry:     prometheusRegistry,
 		HealthChecker:          healthChecker,
 	}
 	if c.Expiry.SigningKeys != "" {
@@ -323,7 +325,7 @@ func runServe(options serveOptions) error {
 	}
 
 	telemetryRouter := http.NewServeMux()
-	telemetryRouter.Handle("/metrics", promhttp.HandlerFor(prometheusRegistry, promhttp.HandlerOpts{}))
+	telemetryRouter.Handle("/metrics", promExporter)
 
 	// Configure health checker
 	{
@@ -452,7 +454,6 @@ func runServe(options serveOptions) error {
 		grpcSrv := grpc.NewServer(grpcOptions...)
 		api.RegisterDexServer(grpcSrv, server.NewAPI(serverConfig.Storage, logger, version))
 
-		grpcMetrics.InitializeMetrics(grpcSrv)
 		if c.GRPC.Reflection {
 			logger.Info("enabling reflection in grpc service")
 			reflection.Register(grpcSrv)

go.mod

@@ -9,26 +9,30 @@ require (
 	github.com/beevik/etree v1.1.0
 	github.com/coreos/go-oidc/v3 v3.0.0
 	github.com/dexidp/dex/api/v2 v2.0.0
-	github.com/felixge/httpsnoop v1.0.2
 	github.com/ghodss/yaml v1.0.0
 	github.com/go-ldap/ldap/v3 v3.3.0
 	github.com/go-sql-driver/mysql v1.6.0
 	github.com/gorilla/handlers v1.5.1
 	github.com/gorilla/mux v1.8.0
-	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
 	github.com/kylelemons/godebug v1.1.0
 	github.com/lib/pq v1.10.2
 	github.com/mattermost/xml-roundtrip-validator v0.1.0
 	github.com/mattn/go-sqlite3 v1.14.7
 	github.com/oklog/run v1.1.0
 	github.com/pkg/errors v0.9.1
-	github.com/prometheus/client_golang v1.11.0
 	github.com/russellhaering/goxmldsig v1.1.0
 	github.com/sirupsen/logrus v1.8.1
 	github.com/spf13/cobra v1.1.3
 	github.com/stretchr/testify v1.7.0
 	go.etcd.io/etcd/client/pkg/v3 v3.5.0
 	go.etcd.io/etcd/client/v3 v3.5.0
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.21.0
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.21.0
+	go.opentelemetry.io/contrib/instrumentation/runtime v0.21.0
+	go.opentelemetry.io/otel v1.0.0-RC1
+	go.opentelemetry.io/otel/exporters/metric/prometheus v0.21.0
+	go.opentelemetry.io/otel/sdk v1.0.0-RC1
+	go.opentelemetry.io/otel/sdk/metric v0.21.0
 	golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2
 	golang.org/x/net v0.0.0-20210503060351-7fd8e65b6420
 	golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c

go.sum

@@ -67,6 +67,8 @@ github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmV
 github.com/armon/go-radix v0.0.0-20180808171621-7fddfc383310/go.mod h1:ufUuZ+zHj4x4TnLV4JWEpy2hxWSpsRywHrMgIH9cCH8=
 github.com/beevik/etree v1.1.0 h1:T0xke/WvNtMoCqgzPhkX2r4rjY3GDZFi+FjpRZY2Jbs=
 github.com/beevik/etree v1.1.0/go.mod h1:r8Aw8JqVegEf0w2fDnATrX9VpkMcyFeM0FhwO62wh+A=
+github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
+github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -223,7 +225,6 @@ github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
 github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/grpc-ecosystem/go-grpc-middleware v1.0.0/go.mod h1:FiyG127CGDf3tlThmgyCl78X/SZQqEOJBCDaAfeWzPs=
-github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0 h1:Ovs26xHkKqVztRpIrF/92BcuyuQ/YW4NSIpoGtfXNho=
 github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0/go.mod h1:8NvIoxWQoOIhqOTXgfV/d3M/q6VIi02HzZEHgUlZvzk=
 github.com/grpc-ecosystem/grpc-gateway v1.9.0/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
 github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
@@ -418,9 +419,37 @@ go.opencensus.io v0.22.4/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.opencensus.io v0.23.0 h1:gqCw0LfLxScz8irSi8exQc7fyQ0fKQU/qnC/X8+V/1M=
 go.opencensus.io v0.23.0/go.mod h1:XItmlyltB5F7CS4xOC1DcqMoFqwtC6OG2xF7mCv7P7E=
+go.opentelemetry.io/contrib v0.21.0 h1:RMJ6GlUVzLYp/zmItxTTdAmr1gnpO/HHMFmvjAhvJQM=
+go.opentelemetry.io/contrib v0.21.0/go.mod h1:EH4yDYeNoaTqn/8yCWQmfNB78VHfGX2Jt2bvnvzBlGM=
+go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.21.0 h1:68WZYF6CrnsXIVDYc51cR9VmTX2IM7y0svo7s4lu5kQ=
+go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.21.0/go.mod h1:Vm5u/mtkj1OMhtao0v+BGo2LUoLCgHYXvRmj0jWITlE=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.21.0 h1:G1vNyNfKknFvrKVC8ga8EYIECy0s5D/QPW4QPRSMhwc=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.21.0/go.mod h1:JQAtechjxLEL81EjmbRwxBq/XEzGaHcsPuDHAx54hg4=
+go.opentelemetry.io/contrib/instrumentation/runtime v0.21.0 h1:fMIgVGQgIuXQFEhE5FiwNS2f1cBccIjgoGZtZDrvRFQ=
+go.opentelemetry.io/contrib/instrumentation/runtime v0.21.0/go.mod h1:O/u1pXAUgsNtVk7WLljP+qE0iJNNyHYKynZJHtOoKKI=
+go.opentelemetry.io/otel v1.0.0-RC1 h1:4CeoX93DNTWt8awGK9JmNXzF9j7TyOu9upscEdtcdXc=
+go.opentelemetry.io/otel v1.0.0-RC1/go.mod h1:x9tRa9HK4hSSq7jf2TKbqFbtt58/TGk0f9XiEYISI1I=
+go.opentelemetry.io/otel/exporters/metric/prometheus v0.21.0 h1:XvcDyI/229CHoZ3USFyChVwBYHroGTOgEcJ2Pvc8XNk=
+go.opentelemetry.io/otel/exporters/metric/prometheus v0.21.0/go.mod h1:hBPZqhLN4cgY/bgEbCOL2WDc7kR/g5DArE/kbEVib7U=
+go.opentelemetry.io/otel/internal/metric v0.21.0 h1:gZlIBo5O51hZOOZz8vEcuRx/l5dnADadKfpT70AELoo=
+go.opentelemetry.io/otel/internal/metric v0.21.0/go.mod h1:iOfAaY2YycsXfYD4kaRSbLx2LKmfpKObWBEv9QK5zFo=
+go.opentelemetry.io/otel/metric v0.21.0 h1:ZtcJlHqVE4l8Su0WOLOd9fEPheJuYEiQ0wr9wv2p25I=
+go.opentelemetry.io/otel/metric v0.21.0/go.mod h1:JWCt1bjivC4iCrz/aCrM1GSw+ZcvY44KCbaeeRhzHnc=
+go.opentelemetry.io/otel/oteltest v1.0.0-RC1 h1:G685iP3XiskCwk/z0eIabL55XUl2gk0cljhGk9sB0Yk=
+go.opentelemetry.io/otel/oteltest v1.0.0-RC1/go.mod h1:+eoIG0gdEOaPNftuy1YScLr1Gb4mL/9lpDkZ0JjMRq4=
+go.opentelemetry.io/otel/sdk v1.0.0-RC1 h1:Sy2VLOOg24bipyC29PhuMXYNJrLsxkie8hyI7kUlG9Q=
+go.opentelemetry.io/otel/sdk v1.0.0-RC1/go.mod h1:kj6yPn7Pgt5ByRuwesbaWcRLA+V7BSDg3Hf8xRvsvf8=
+go.opentelemetry.io/otel/sdk/export/metric v0.21.0 h1:4tSMVkDbvrowOeP/6rOfGABEWv5n+0gCfhI/TWleUvc=
+go.opentelemetry.io/otel/sdk/export/metric v0.21.0/go.mod h1:gTaOMSQmL4zfsTL47desIPbPla5MyMG29lN3PzcibVg=
+go.opentelemetry.io/otel/sdk/metric v0.21.0 h1:LNLUj35NNdEpyJQwj/htiEsfnY6GeTIwYHweCJNV+nc=
+go.opentelemetry.io/otel/sdk/metric v0.21.0/go.mod h1:OHOcF8ZjE/L8oL/QXpUFWklPwtaukrfHgoAiPek53rQ=
+go.opentelemetry.io/otel/trace v1.0.0-RC1 h1:jrjqKJZEibFrDz+umEASeU3LvdVyWKlnTh7XEfwrT58=
+go.opentelemetry.io/otel/trace v1.0.0-RC1/go.mod h1:86UHmyHWFEtWjfWPSbu0+d0Pf9Q6e1U+3ViBOc+NXAg=
 go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.7.0 h1:ADUqmZGgLDDfbSL9ZmPxKTybcoEYHgpYfELNoN+7hsw=
 go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
+go.uber.org/goleak v1.1.10 h1:z+mqJhf6ss6BSfSM671tgKyZBFPTTJM+HLxnhPC3wu0=
+go.uber.org/goleak v1.1.10/go.mod h1:8a7PlsEVH3e/a/GLqe5IIrQx6GzcnRmZEufDUTk4A7A=
 go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/0=
 go.uber.org/multierr v1.6.0 h1:y6IPFStTAIT5Ytl7/XYmHvzXQ7S3g/IeZW9hyZ5thw4=
 go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=
@@ -461,6 +490,7 @@ golang.org/x/lint v0.0.0-20191125180803-fdd1cda4f05f/go.mod h1:5qLYkcX4OjUUV8bRu
 golang.org/x/lint v0.0.0-20200130185559-910be7a94367/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
+golang.org/x/lint v0.0.0-20210508222113-6edffad5e616 h1:VLliZ0d+/avPrXXH+OakdXhpJuEoBZuwh1m2j7U6Iug=
 golang.org/x/lint v0.0.0-20210508222113-6edffad5e616/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/mobile v0.0.0-20190312151609-d3739f865fa6/go.mod h1:z+o9i4GpDbdi3rU15maQ/Ox0txvL9dWGYEHz965HBQE=
 golang.org/x/mobile v0.0.0-20190719004257-d2bd2a29d028/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
@@ -624,6 +654,7 @@ golang.org/x/tools v0.0.0-20190628153133-6cdbf07be9d0/go.mod h1:/rFqwRUd4F7ZHNgw
 golang.org/x/tools v0.0.0-20190816200558-6889da9d5479/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20190911174233-4f2ddba30aff/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191012152004-8de300cfc20a/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20191108193012-7d206e10da11/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191112195655-aa38f8e97acc/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191113191852-77e3bb0ad9e7/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191115202509-3a792d9c32b2/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
@@ -659,6 +690,7 @@ golang.org/x/tools v0.0.0-20210105154028-b0ab187a4818/go.mod h1:emZCQorbCU4vsT4f
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
 golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.2 h1:kRBLX7v7Af8W7Gdbbc908OJcdgtK8bOz9Uaj8/F1ACA=
 golang.org/x/tools v0.1.2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

server/metrics.go

@@ -0,0 +1,28 @@
+package server
+
+import (
+	"net/http"
+
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
+)
+
+var _ http.Handler = (*metricsHandler)(nil)
+
+type metricsHandler struct {
+	route   string
+	handler http.Handler
+}
+
+func (m *metricsHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	l, _ := otelhttp.LabelerFromContext(r.Context())
+	l.Add(semconv.HTTPMethodKey.String(r.Method))
+	l.Add(semconv.HTTPRouteKey.String(r.URL.EscapedPath()))
+
+	m.handler.ServeHTTP(w, r)
+}
+
+func wrapWithMetrics(path string, handler http.Handler) http.Handler {
+	h := metricsHandler{route: path, handler: handler}
+	return otelhttp.NewHandler(&h, "dex")
+}

server/server.go

@@ -11,17 +11,14 @@ import (
 	"net/url"
 	"os"
 	"path"
-	"strconv"
 	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
 
 	gosundheit "github.com/AppsFlyer/go-sundheit"
-	"github.com/felixge/httpsnoop"
 	"github.com/gorilla/handlers"
 	"github.com/gorilla/mux"
-	"github.com/prometheus/client_golang/prometheus"
 	"golang.org/x/crypto/bcrypt"
 
 	"github.com/dexidp/dex/connector"
@@ -100,8 +97,6 @@ type Config struct {
 
 	Logger log.Logger
 
-	PrometheusRegistry *prometheus.Registry
-
 	HealthChecker gosundheit.Health
 }
 
@@ -279,32 +274,9 @@ func newServer(ctx context.Context, c Config, rotationStrategy rotationStrategy)
 		}
 	}
 
-	instrumentHandlerCounter := func(_ string, handler http.Handler) http.HandlerFunc {
-		return handler.ServeHTTP
-	}
-
-	if c.PrometheusRegistry != nil {
-		requestCounter := prometheus.NewCounterVec(prometheus.CounterOpts{
-			Name: "http_requests_total",
-			Help: "Count of all HTTP requests.",
-		}, []string{"handler", "code", "method"})
-
-		err = c.PrometheusRegistry.Register(requestCounter)
-		if err != nil {
-			return nil, fmt.Errorf("server: Failed to register Prometheus HTTP metrics: %v", err)
-		}
-
-		instrumentHandlerCounter = func(handlerName string, handler http.Handler) http.HandlerFunc {
-			return func(w http.ResponseWriter, r *http.Request) {
-				m := httpsnoop.CaptureMetrics(handler, w, r)
-				requestCounter.With(prometheus.Labels{"handler": handlerName, "code": strconv.Itoa(m.Code), "method": r.Method}).Inc()
-			}
-		}
-	}
-
 	r := mux.NewRouter()
 	handle := func(p string, h http.Handler) {
-		r.Handle(path.Join(issuerURL.Path, p), instrumentHandlerCounter(p, h))
+		r.Handle(path.Join(issuerURL.Path, p), wrapWithMetrics(p, h))
 	}
 	handleFunc := func(p string, h http.HandlerFunc) {
 		handle(p, h)
@@ -325,7 +297,7 @@ func newServer(ctx context.Context, c Config, rotationStrategy rotationStrategy)
 			)
 			handler = cors(handler)
 		}
-		r.Handle(path.Join(issuerURL.Path, p), instrumentHandlerCounter(p, handler))
+		r.Handle(path.Join(issuerURL.Path, p), wrapWithMetrics(p, handler))
 	}
 	r.NotFoundHandler = http.NotFoundHandler()
 

server/server_test.go

@@ -24,7 +24,6 @@ import (
 	gosundheit "github.com/AppsFlyer/go-sundheit"
 	"github.com/coreos/go-oidc/v3/oidc"
 	"github.com/kylelemons/godebug/pretty"
-	"github.com/prometheus/client_golang/prometheus"
 	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/crypto/bcrypt"
@@ -95,9 +94,8 @@ func newTestServer(ctx context.Context, t *testing.T, updateConfig func(c *Confi
 		Web: WebConfig{
 			Dir: "../web",
 		},
-		Logger:             logger,
-		PrometheusRegistry: prometheus.NewRegistry(),
-		HealthChecker:      gosundheit.New(),
+		Logger:        logger,
+		HealthChecker: gosundheit.New(),
 	}
 	if updateConfig != nil {
 		updateConfig(&config)
@@ -144,8 +142,7 @@ func newTestServerMultipleConnectors(ctx context.Context, t *testing.T, updateCo
 		Web: WebConfig{
 			Dir: "../web",
 		},
-		Logger:             logger,
-		PrometheusRegistry: prometheus.NewRegistry(),
+		Logger: logger,
 	}
 	if updateConfig != nil {
 		updateConfig(&config)