Merge pull request #135746 from richabanker/move-flagz

Move apiserver's flagz installation to genericapiserver alongside statusz

pkg/controlplane/apiserver/server.go

@@ -32,12 +32,10 @@ import (
 	genericregistry "k8s.io/apiserver/pkg/registry/generic"
 	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/dynamiccertificates"
-	"k8s.io/apiserver/pkg/server/flagz"
 	serverstorage "k8s.io/apiserver/pkg/server/storage"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	clientgoinformers "k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes"
-	zpagesfeatures "k8s.io/component-base/zpages/features"
 	"k8s.io/component-helpers/apimachinery/lease"
 	"k8s.io/klog/v2"
 	"k8s.io/utils/clock"
@@ -154,12 +152,6 @@ func (c completedConfig) New(name string, delegationTarget genericapiserver.Dele
 		return nil, fmt.Errorf("failed to get listener address: %w", err)
 	}
 
-	if utilfeature.DefaultFeatureGate.Enabled(zpagesfeatures.ComponentFlagz) {
-		if c.Generic.Flagz != nil {
-			flagz.Install(s.GenericAPIServer.Handler.NonGoRestfulMux, name, c.Generic.Flagz)
-		}
-	}
-
 	if utilfeature.DefaultFeatureGate.Enabled(apiserverfeatures.CoordinatedLeaderElection) {
 		leaseInformer := s.VersionedInformers.Coordination().V1().Leases()
 		lcInformer := s.VersionedInformers.Coordination().V1beta1().LeaseCandidates()

staging/src/k8s.io/apiserver/pkg/server/config.go

@@ -830,6 +830,7 @@ func (c completedConfig) New(name string, delegationTarget DelegationTarget) (*G
 		UnprotectedDebugSocket:         debugSocket,
 
 		listedPathProvider: apiServerHandler,
+		Flagz:              c.Flagz,
 
 		minRequestTimeout:                   time.Duration(c.MinRequestTimeout) * time.Second,
 		ShutdownTimeout:                     c.RequestTimeout,

staging/src/k8s.io/apiserver/pkg/server/genericapiserver.go

@@ -49,6 +49,7 @@ import (
 	discoveryendpoint "k8s.io/apiserver/pkg/endpoints/discovery/aggregated"
 	"k8s.io/apiserver/pkg/features"
 	"k8s.io/apiserver/pkg/registry/rest"
+	"k8s.io/apiserver/pkg/server/flagz"
 	"k8s.io/apiserver/pkg/server/healthz"
 	"k8s.io/apiserver/pkg/server/routes"
 	"k8s.io/apiserver/pkg/server/statusz"
@@ -113,6 +114,9 @@ type GenericAPIServer struct {
 	// LoopbackClientConfig is a config for a privileged loopback connection to the API server
 	LoopbackClientConfig *restclient.Config
 
+	// Flagz is used to set up flagz endpoint.
+	Flagz flagz.Reader
+
 	// minRequestTimeout is how short the request timeout can be.  This is used to build the RESTHandler
 	minRequestTimeout time.Duration
 
@@ -463,8 +467,15 @@ func (s *GenericAPIServer) PrepareRun() preparedGenericAPIServer {
 	}
 	s.installReadyz()
 
+	componentName := "apiserver"
 	if utilfeature.DefaultFeatureGate.Enabled(zpagesfeatures.ComponentStatusz) {
-		statusz.Install(s.Handler.NonGoRestfulMux, "apiserver", statusz.NewRegistry(s.EffectiveVersion, statusz.WithListedPaths(s.ListedPaths())))
+		statusz.Install(s.Handler.NonGoRestfulMux, componentName, statusz.NewRegistry(s.EffectiveVersion, statusz.WithListedPaths(s.ListedPaths())))
+	}
+
+	if utilfeature.DefaultFeatureGate.Enabled(zpagesfeatures.ComponentFlagz) {
+		if s.Flagz != nil {
+			flagz.Install(s.Handler.NonGoRestfulMux, componentName, s.Flagz)
+		}
 	}
 
 	return preparedGenericAPIServer{s}

test/integration/controlplane/kube_apiserver_test.go

@@ -149,14 +149,14 @@ func TestFlagz(t *testing.T) {
 		t.Fatalf("Unexpected error: %v", err)
 	}
 
-	wantBodyStr := "kube-apiserver flagz\nWarning: This endpoint is not meant to be machine parseable"
+	wantBodyStr := "apiserver flagz\nWarning: This endpoint is not meant to be machine parseable"
 	wantBodyJSON := &flagzv1alpha1.Flagz{
 		TypeMeta: metav1.TypeMeta{
 			Kind:       "Flagz",
 			APIVersion: "config.k8s.io/v1alpha1",
 		},
 		ObjectMeta: metav1.ObjectMeta{
-			Name: "kube-apiserver",
+			Name: "apiserver",
 		},
 	}