Add feature gate for FieldValidation

pkg/features/kube_features.go

@@ -904,6 +904,7 @@ var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureS
 	genericfeatures.WarningHeaders:                      {Default: true, PreRelease: featuregate.GA, LockToDefault: true}, // remove in 1.24
 	genericfeatures.OpenAPIEnums:                        {Default: false, PreRelease: featuregate.Alpha},
 	genericfeatures.CustomResourceValidationExpressions: {Default: false, PreRelease: featuregate.Alpha},
+	genericfeatures.FieldValidation:                     {Default: false, PreRelease: featuregate.Alpha},
 	// features that enable backwards compatibility but are scheduled to be removed
 	// ...
 	HPAScaleToZero: {Default: false, PreRelease: featuregate.Alpha},

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

@@ -463,6 +463,10 @@ func isDryRun(url *url.URL) bool {
 // media type, because the list of media types that support field validation are a subset of
 // all supported media types (protobuf does not support field validation).
 func fieldValidation(req *http.Request) (runtime.FieldValidationDirective, error) {
+	if !utilfeature.DefaultFeatureGate.Enabled(features.FieldValidation) {
+		return runtime.IgnoreFieldValidation, nil
+	}
+
 	supportedContentTypes := []string{runtime.ContentTypeJSON, runtime.ContentTypeJSONMergePatch, runtime.ContentTypeJSONStrategicMergePatch, runtime.ContentTypeYAML}
 	contentType := req.Header.Get("Content-Type")
 	// TODO: not sure if it is okay to assume empty content type is a valid one

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

@@ -185,6 +185,13 @@ const (
 	//
 	// Enables expression validation for Custom Resource
 	CustomResourceValidationExpressions featuregate.Feature = "CustomResourceValidationExpressions"
+
+	// owner: @kevindelgado
+	// kep: http://kep.k8s.io/2885
+	// alpha: v1.23
+	//
+	// Enables server-side field validation.
+	FieldValidation featuregate.Feature = "FieldValidation"
 )
 
 func init() {
@@ -215,4 +222,5 @@ var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureS
 	APIServerTracing:                    {Default: false, PreRelease: featuregate.Alpha},
 	OpenAPIEnums:                        {Default: false, PreRelease: featuregate.Alpha},
 	CustomResourceValidationExpressions: {Default: false, PreRelease: featuregate.Alpha},
+	FieldValidation:                     {Default: false, PreRelease: featuregate.Alpha},
 }

test/integration/apiserver/field_validation_test.go

@@ -45,7 +45,7 @@ import (
 // TestFieldValidationPost tests POST requests containing unknown fields with
 // strict and non-strict field validation.
 func TestFieldValidationPost(t *testing.T) {
-	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.ServerSideApply, true)()
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
 
 	_, client, closeFn := setup(t)
 	defer closeFn()
@@ -120,7 +120,7 @@ func TestFieldValidationPost(t *testing.T) {
 // TestFieldValidationPut tests PUT requests containing unknown fields with
 // strict and non-strict field validation.
 func TestFieldValidationPut(t *testing.T) {
-	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.ServerSideApply, true)()
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
 
 	_, client, closeFn := setup(t)
 	defer closeFn()
@@ -210,6 +210,8 @@ func TestFieldValidationPut(t *testing.T) {
 
 // Benchmark field validation for strict vs non-strict
 func BenchmarkFieldValidationPostPut(b *testing.B) {
+	defer featuregatetesting.SetFeatureGateDuringTest(b, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
+
 	_, client, closeFn := setup(b)
 	defer closeFn()
 
@@ -384,6 +386,7 @@ type smpTestCase struct {
 // but succeeds when fieldValidation is ignored.
 func TestFieldValidationSMP(t *testing.T) {
 	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.ServerSideApply, true)()
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
 
 	_, client, closeFn := setup(t)
 	defer closeFn()
@@ -420,6 +423,7 @@ func TestFieldValidationSMP(t *testing.T) {
 // Benchmark strategic-merge-patch field validation for strict vs non-strict
 func BenchmarkFieldValidationSMP(b *testing.B) {
 	defer featuregatetesting.SetFeatureGateDuringTest(b, utilfeature.DefaultFeatureGate, features.ServerSideApply, true)()
+	defer featuregatetesting.SetFeatureGateDuringTest(b, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
 
 	_, client, closeFn := setup(b)
 	defer closeFn()
@@ -513,6 +517,8 @@ func patchCRDTestSetup(t testing.TB, server kubeapiservertesting.TestServer, nam
 // TestFieldValidationPatchCRD tests that server-side schema validation
 // works for jsonpatch and mergepatch requests.
 func TestFieldValidationPatchCRD(t *testing.T) {
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
+
 	var testcases = []struct {
 		name         string
 		patchType    types.PatchType
@@ -600,6 +606,8 @@ func TestFieldValidationPatchCRD(t *testing.T) {
 
 // Benchmark patch CRD for strict vs non-strict
 func BenchmarkFieldValidationPatchCRD(b *testing.B) {
+	defer featuregatetesting.SetFeatureGateDuringTest(b, utilfeature.DefaultFeatureGate, features.FieldValidation, true)()
+
 	benchmarks := []struct {
 		name        string
 		patchType   types.PatchType