Merge pull request #1587 from 2uasimojo/issues/1423/optional

⚠️ Disable the `rest_client_request_latency_seconds` metric by default

Author: k8s-ci-robot

pkg/metrics/client_go_adapter.go

@@ -52,7 +52,24 @@ const (
 
 var (
 	// client metrics.
-	requestLatency = prometheus.NewHistogramVec(prometheus.HistogramOpts{
+
+	// RequestLatency reports the request latency in seconds per verb/URL.
+	// Deprecated: This metric is deprecated for removal in a future release: using the URL as a
+	// dimension results in cardinality explosion for some consumers. It was deprecated upstream
+	// in k8s v1.14 and hidden in v1.17 via https://github.com/kubernetes/kubernetes/pull/83836.
+	// It is not registered by default. To register:
+	//	import (
+	//		clientmetrics "k8s.io/client-go/tools/metrics"
+	//		clmetrics "sigs.k8s.io/controller-runtime/metrics"
+	//	)
+	//
+	//	func init() {
+	//		clmetrics.Registry.MustRegister(clmetrics.RequestLatency)
+	//		clientmetrics.Register(clientmetrics.RegisterOpts{
+	//			RequestLatency: clmetrics.LatencyAdapter
+	//		})
+	//	}
+	RequestLatency = prometheus.NewHistogramVec(prometheus.HistogramOpts{
 		Subsystem: RestClientSubsystem,
 		Name:      LatencyKey,
 		Help:      "Request latency in seconds. Broken down by verb and URL.",
@@ -127,13 +144,11 @@ func init() {
 // registerClientMetrics sets up the client latency metrics from client-go.
 func registerClientMetrics() {
 	// register the metrics with our registry
-	Registry.MustRegister(requestLatency)
 	Registry.MustRegister(requestResult)
 
 	// register the metrics with client-go
 	clientmetrics.Register(clientmetrics.RegisterOpts{
-		RequestLatency: &latencyAdapter{metric: requestLatency},
-		RequestResult:  &resultAdapter{metric: requestResult},
+		RequestResult: &resultAdapter{metric: requestResult},
 	})
 }
 
@@ -159,11 +174,13 @@ func registerReflectorMetrics() {
 // copied (more-or-less directly) from k8s.io/kubernetes setup code
 // (which isn't anywhere in an easily-importable place).
 
-type latencyAdapter struct {
+// LatencyAdapter implements LatencyMetric.
+type LatencyAdapter struct {
 	metric *prometheus.HistogramVec
 }
 
-func (l *latencyAdapter) Observe(_ context.Context, verb string, u url.URL, latency time.Duration) {
+// Observe increments the request latency metric for the given verb/URL.
+func (l *LatencyAdapter) Observe(_ context.Context, verb string, u url.URL, latency time.Duration) {
 	l.metric.WithLabelValues(verb, u.String()).Observe(latency.Seconds())
 }