metrics: use legacyregister instead of new registry

Signed-off-by: Iceber Gu <[email protected]>

pkg/kube_state_metrics/server.go

@@ -13,6 +13,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/prometheus/exporter-toolkit/web"
+	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/klog/v2"
 
 	"github.com/clusterpedia-io/clusterpedia/pkg/metrics"
@@ -26,7 +27,7 @@ type ServerConfig struct {
 }
 
 func RunServer(config ServerConfig, getter ClusterMetricsWriterListGetter) {
-	durationVec := promauto.With(metrics.DefaultRegistry()).NewHistogramVec(
+	durationVec := promauto.With(legacyregistry.Registerer()).NewHistogramVec(
 		prometheus.HistogramOpts{
 			Name:        "http_request_duration_seconds",
 			Help:        "A histogram of requests for clusterpedia's kube-state-metrics metrics handler.",

pkg/metrics/metrics.go

@@ -1,16 +1,12 @@
 package metrics
 
 import (
-	"github.com/prometheus/client_golang/prometheus"
 	versionCollector "github.com/prometheus/client_golang/prometheus/collectors/version"
+	"k8s.io/component-base/metrics/legacyregistry"
 )
 
-var registry = prometheus.NewRegistry()
-
-func DefaultRegistry() prometheus.Registerer {
-	return registry
-}
-
 func init() {
-	registry.MustRegister(versionCollector.NewCollector("clusterpedia_kube_state_metrics"))
+	legacyregistry.RawMustRegister(
+		versionCollector.NewCollector("clusterpedia_kube_state_metrics"),
+	)
 }

pkg/metrics/server.go

@@ -4,8 +4,9 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/prometheus/exporter-toolkit/web"
+	"k8s.io/component-base/metrics"
+	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/klog/v2"
 
 	"github.com/clusterpedia-io/clusterpedia/pkg/pprof"
@@ -37,10 +38,13 @@ func RunServer(config Config) {
 
 func buildMetricsServer(config Config) *http.ServeMux {
 	mux := http.NewServeMux()
-	mux.Handle("/metrics", promhttp.HandlerFor(registry, promhttp.HandlerOpts{
-		ErrorLog:           Logger,
-		DisableCompression: config.DisableGZIPEncoding,
-	}))
+	mux.Handle("/metrics", metrics.HandlerWithReset(
+		legacyregistry.DefaultGatherer.(metrics.KubeRegistry),
+		metrics.HandlerOpts{
+			ErrorLog:           Logger,
+			DisableCompression: config.DisableGZIPEncoding,
+		}),
+	)
 	// add profiler
 	pprof.RegisterProfileHandler(mux)
 	// Add index