Add statusz endpoint for kube-proxy

Author: Henrywu573

cmd/kube-proxy/app/server.go

@@ -60,7 +60,9 @@ import (
 	"k8s.io/component-base/metrics/prometheus/slis"
 	"k8s.io/component-base/version"
 	"k8s.io/component-base/version/verflag"
+	zpagesfeatures "k8s.io/component-base/zpages/features"
 	"k8s.io/component-base/zpages/flagz"
+	"k8s.io/component-base/zpages/statusz"
 	nodeutil "k8s.io/component-helpers/node/util"
 	"k8s.io/klog/v2"
 	api "k8s.io/kubernetes/pkg/apis/core"
@@ -78,6 +80,11 @@ import (
 	netutils "k8s.io/utils/net"
 )
 
+const (
+	// kubeProxy defines variable used internally when referring to kube-proxy component
+	kubeProxy = "kube-proxy"
+)
+
 func init() {
 	utilruntime.Must(metricsfeatures.AddFeatureGates(utilfeature.DefaultMutableFeatureGate))
 	utilruntime.Must(logsapi.AddFeatureGates(utilfeature.DefaultMutableFeatureGate))
@@ -93,7 +100,7 @@ func NewProxyCommand() *cobra.Command {
 	opts := NewOptions()
 
 	cmd := &cobra.Command{
-		Use: "kube-proxy",
+		Use: kubeProxy,
 		Long: `The Kubernetes network proxy runs on each node. This
 reflects services as defined in the Kubernetes API on each node and can do simple
 TCP, UDP, and SCTP stream forwarding or round robin TCP, UDP, and SCTP forwarding across a set of backends.
@@ -214,7 +221,7 @@ func newProxyServer(ctx context.Context, config *kubeproxyconfig.KubeProxyConfig
 	}
 
 	s.Broadcaster = events.NewBroadcaster(&events.EventSinkImpl{Interface: s.Client.EventsV1()})
-	s.Recorder = s.Broadcaster.NewRecorder(proxyconfigscheme.Scheme, "kube-proxy")
+	s.Recorder = s.Broadcaster.NewRecorder(proxyconfigscheme.Scheme, kubeProxy)
 
 	s.NodeRef = &v1.ObjectReference{
 		Kind:      "Node",
@@ -443,7 +450,7 @@ func serveMetrics(ctx context.Context, bindAddress string, proxyMode kubeproxyco
 		return
 	}
 
-	proxyMux := mux.NewPathRecorderMux("kube-proxy")
+	proxyMux := mux.NewPathRecorderMux(kubeProxy)
 	healthz.InstallHandler(proxyMux)
 	slis.SLIMetricsWithReset{}.Install(proxyMux)
 
@@ -466,6 +473,10 @@ func serveMetrics(ctx context.Context, bindAddress string, proxyMode kubeproxyco
 		flagz.Install(proxyMux, "kube-proxy", flagzReader)
 	}
 
+	if utilfeature.DefaultFeatureGate.Enabled(zpagesfeatures.ComponentStatusz) {
+		statusz.Install(proxyMux, kubeProxy, statusz.NewRegistry())
+	}
+
 	fn := func() {
 		var err error
 		defer func() {