Add CBOR feature gates.

For alpha, there is one apiserver feature gate and two client-go feature gates controlling
CBOR. They were initially wired to separate test-only feature gate instances in order to prevent
them from being configurable at runtime via command-line flags or environment variables (for
client-go feature gates outside of Kubernetes components). All of the integration tests required by
the KEP as alpha criteria have been implemented. This adds the feature gates to the usual feature
gate instances and removes the temporary code to support separate test-only feature gate instances.

Author: benluddy

pkg/features/client_adapter.go

@@ -67,3 +67,10 @@ func (a *clientAdapter) Add(in map[clientfeatures.Feature]clientfeatures.Feature
 	}
 	return a.mfg.Add(out)
 }
+
+// Set implements the unexported interface that client-go feature gate testing expects for
+// ek8s.io/client-go/features/testing.SetFeatureDuringTest. This is necessary for integration tests
+// to set test overrides for client-go feature gates.
+func (a *clientAdapter) Set(name clientfeatures.Feature, enabled bool) error {
+	return a.mfg.SetFromMap(map[string]bool{string(name): enabled})
+}

pkg/features/versioned_kube_features.go

@@ -245,6 +245,10 @@ var defaultVersionedKubernetesFeatureGates = map[featuregate.Feature]featuregate
 		{Version: version.MustParse("1.32"), Default: true, PreRelease: featuregate.Beta},
 	},
 
+	genericfeatures.CBORServingAndStorage: {
+		{Version: version.MustParse("1.32"), Default: false, PreRelease: featuregate.Alpha},
+	},
+
 	genericfeatures.ConcurrentWatchObjectDecode: {
 		{Version: version.MustParse("1.31"), Default: false, PreRelease: featuregate.Beta},
 	},

staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go

@@ -327,7 +327,7 @@ func (r *crdHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		string(types.MergePatchType),
 		string(types.ApplyYAMLPatchType),
 	}
-	if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 		supportedTypes = append(supportedTypes, string(types.ApplyCBORPatchType))
 	}
 
@@ -913,7 +913,7 @@ func (r *crdHandler) getOrCreateServingInfoFor(uid types.UID, name string) (*crd
 			},
 		}
 
-		if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+		if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 			negotiatedSerializer.supportedMediaTypes = append(negotiatedSerializer.supportedMediaTypes, newCBORSerializerInfo(creator, typer))
 		}
 
@@ -981,7 +981,7 @@ func (r *crdHandler) getOrCreateServingInfoFor(uid types.UID, name string) (*crd
 		scaleConverter := scale.NewScaleConverter()
 		scaleScope.Subresource = "scale"
 		var opts []serializer.CodecFactoryOptionsMutator
-		if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+		if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 			opts = append(opts, serializer.WithSerializer(newCBORSerializerInfo))
 		}
 		scaleScope.Serializer = serializer.NewCodecFactory(scaleConverter.Scheme(), opts...)

staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/options/options.go

@@ -139,7 +139,7 @@ func NewCRDRESTOptionsGetter(etcdOptions genericoptions.EtcdOptions, resourceTra
 	ucbor := cbor.NewSerializer(unstructuredscheme.NewUnstructuredCreator(), unstructuredscheme.NewUnstructuredObjectTyper())
 
 	encoder := unstructured.UnstructuredJSONScheme
-	if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 		encoder = ucbor
 	}
 

staging/src/k8s.io/apiextensions-apiserver/test/integration/cbor_test.go

@@ -69,7 +69,7 @@ func TestCBORStorageEnablement(t *testing.T) {
 
 	func() {
 		t.Log("starting server with feature gate disabled")
-		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.TestOnlyFeatureGate, features.TestOnlyCBORServingAndStorage, false)
+		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.CBORServingAndStorage, false)
 		tearDown, apiExtensionsClientset, dynamicClient, etcdClient, _, err := fixtures.StartDefaultServerWithClientsAndEtcd(t, "--etcd-prefix", etcdPrefix)
 		if err != nil {
 			t.Fatal(err)
@@ -109,7 +109,7 @@ func TestCBORStorageEnablement(t *testing.T) {
 
 	func() {
 		t.Log("starting server with feature gate enabled")
-		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.TestOnlyFeatureGate, features.TestOnlyCBORServingAndStorage, true)
+		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.CBORServingAndStorage, true)
 		tearDown, _, dynamicClient, etcdClient, _, err := fixtures.StartDefaultServerWithClientsAndEtcd(t, "--etcd-prefix", etcdPrefix)
 		if err != nil {
 			t.Fatal(err)
@@ -159,7 +159,7 @@ func TestCBORStorageEnablement(t *testing.T) {
 
 	func() {
 		t.Log("starting server with feature gate disabled")
-		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.TestOnlyFeatureGate, features.TestOnlyCBORServingAndStorage, false)
+		featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.CBORServingAndStorage, false)
 		tearDown, _, dynamicClient, _, _, err := fixtures.StartDefaultServerWithClientsAndEtcd(t, "--etcd-prefix", etcdPrefix)
 		if err != nil {
 			t.Fatal(err)
@@ -185,7 +185,7 @@ func TestCBORServingEnablement(t *testing.T) {
 		{name: "disabled", enabled: false},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
-			featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.TestOnlyFeatureGate, features.TestOnlyCBORServingAndStorage, tc.enabled)
+			featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.CBORServingAndStorage, tc.enabled)
 
 			tearDown, config, _, err := fixtures.StartDefaultServer(t)
 			if err != nil {

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/patch.go

@@ -138,7 +138,7 @@ func PatchResource(r rest.Patcher, scope *RequestScope, admit admission.Interfac
 		case types.ApplyYAMLPatchType:
 			baseContentType = runtime.ContentTypeYAML
 		case types.ApplyCBORPatchType:
-			if !utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+			if !utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 				// This request should have already been rejected by the
 				// Content-Type allowlist check. Return 500 because assumptions are
 				// already broken and the feature is not GA.
@@ -673,7 +673,7 @@ func (p *patcher) patchResource(ctx context.Context, scope *RequestScope) (runti
 		p.mechanism = newApplyPatcher(p, scope.FieldManager, yaml.Unmarshal, yaml.UnmarshalStrict)
 		p.forceAllowCreate = true
 	case types.ApplyCBORPatchType:
-		if !utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+		if !utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 			utilruntime.HandleErrorWithContext(context.TODO(), nil, "CBOR apply requests should be rejected before reaching this point unless the feature gate is enabled.")
 			return nil, false, fmt.Errorf("%v: unimplemented patch type", p.patchType)
 		}

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/responsewriters/writers.go

@@ -286,7 +286,7 @@ func WriteObjectNegotiated(s runtime.NegotiatedSerializer, restrictions negotiat
 	audit.LogResponseObject(req.Context(), object, gv, s)
 
 	var encoder runtime.Encoder
-	if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 		encoder = s.EncoderForVersion(runtime.UseNondeterministicEncoding(serializer.Serializer), gv)
 	} else {
 		encoder = s.EncoderForVersion(serializer.Serializer, gv)

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/watch.go

@@ -77,7 +77,7 @@ func serveWatchHandler(watcher watch.Interface, scope *RequestScope, mediaTypeOp
 	}
 	framer := serializer.StreamSerializer.Framer
 	var encoder runtime.Encoder
-	if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 		encoder = scope.Serializer.EncoderForVersion(runtime.UseNondeterministicEncoding(serializer.StreamSerializer.Serializer), scope.Kind.GroupVersion())
 	} else {
 		encoder = scope.Serializer.EncoderForVersion(serializer.StreamSerializer.Serializer, scope.Kind.GroupVersion())
@@ -102,13 +102,13 @@ func serveWatchHandler(watcher watch.Interface, scope *RequestScope, mediaTypeOp
 		if !ok {
 			return nil, fmt.Errorf("no encoder for %q exists in the requested target %#v", serializer.MediaType, contentSerializer)
 		}
-		if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+		if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 			negotiatedEncoder = contentSerializer.EncoderForVersion(runtime.UseNondeterministicEncoding(info.Serializer), contentKind.GroupVersion())
 		} else {
 			negotiatedEncoder = contentSerializer.EncoderForVersion(info.Serializer, contentKind.GroupVersion())
 		}
 	} else {
-		if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+		if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 			negotiatedEncoder = scope.Serializer.EncoderForVersion(runtime.UseNondeterministicEncoding(serializer.Serializer), contentKind.GroupVersion())
 		} else {
 			negotiatedEncoder = scope.Serializer.EncoderForVersion(serializer.Serializer, contentKind.GroupVersion())

staging/src/k8s.io/apiserver/pkg/endpoints/installer.go

@@ -895,7 +895,7 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 				string(types.StrategicMergePatchType),
 				string(types.ApplyYAMLPatchType),
 			}
-			if utilfeature.TestOnlyFeatureGate.Enabled(features.TestOnlyCBORServingAndStorage) {
+			if utilfeature.DefaultFeatureGate.Enabled(features.CBORServingAndStorage) {
 				supportedTypes = append(supportedTypes, string(types.ApplyCBORPatchType))
 			}
 			handler := metrics.InstrumentRouteFunc(action.Verb, group, version, resource, subresource, requestScope, metrics.APIServerComponent, deprecated, removedRelease, restfulPatchResource(patcher, reqScope, admit, supportedTypes))

staging/src/k8s.io/apiserver/pkg/features/kube_features.go

@@ -92,9 +92,7 @@ const (
 	//
 	// Enables CBOR as a supported encoding for requests and responses, and as the
 	// preferred storage encoding for custom resources.
-	//
-	// This feature is currently PRE-ALPHA and MUST NOT be enabled outside of integration tests.
-	TestOnlyCBORServingAndStorage featuregate.Feature = "TestOnlyCBORServingAndStorage"
+	CBORServingAndStorage featuregate.Feature = "CBORServingAndStorage"
 
 	// owner: @serathius
 	//
@@ -245,7 +243,6 @@ const (
 func init() {
 	runtime.Must(utilfeature.DefaultMutableFeatureGate.Add(defaultKubernetesFeatureGates))
 	runtime.Must(utilfeature.DefaultMutableFeatureGate.AddVersioned(defaultVersionedKubernetesFeatureGates))
-	runtime.Must(utilfeature.TestOnlyMutableFeatureGate.AddVersioned(testOnlyVersionedKubernetesFeatureGates))
 }
 
 // defaultVersionedKubernetesFeatureGates consists of all known Kubernetes-specific feature keys with VersionedSpecs.
@@ -306,6 +303,10 @@ var defaultVersionedKubernetesFeatureGates = map[featuregate.Feature]featuregate
 		{Version: version.MustParse("1.32"), Default: true, PreRelease: featuregate.Beta},
 	},
 
+	CBORServingAndStorage: {
+		{Version: version.MustParse("1.32"), Default: false, PreRelease: featuregate.Alpha},
+	},
+
 	ConcurrentWatchObjectDecode: {
 		{Version: version.MustParse("1.31"), Default: false, PreRelease: featuregate.Beta},
 	},
@@ -417,12 +418,3 @@ var defaultVersionedKubernetesFeatureGates = map[featuregate.Feature]featuregate
 // defaultKubernetesFeatureGates consists of legacy unversioned Kubernetes-specific feature keys.
 // Please do not add to this struct and use defaultVersionedKubernetesFeatureGates instead.
 var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureSpec{}
-
-// testOnlyVersionedKubernetesFeatureGates consists of features that require programmatic enablement
-// for integration testing, but have not yet graduated to alpha in a release and must not be enabled
-// by a runtime option.
-var testOnlyVersionedKubernetesFeatureGates = map[featuregate.Feature]featuregate.VersionedSpecs{
-	TestOnlyCBORServingAndStorage: {
-		{Version: version.MustParse("1.32"), Default: false, PreRelease: featuregate.Alpha},
-	},
-}