drop crd api fields

staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation/validation.go

@@ -196,18 +196,8 @@ func ValidateCustomResourceDefinitionSpec(spec *apiextensions.CustomResourceDefi
 	}
 
 	allErrs = append(allErrs, ValidateCustomResourceDefinitionNames(&spec.Names, fldPath.Child("names"))...)
-
-	if utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceValidation) {
-		allErrs = append(allErrs, ValidateCustomResourceDefinitionValidation(spec.Validation, hasAnyStatusEnabled(spec), fldPath.Child("validation"))...)
-	} else if spec.Validation != nil {
-		allErrs = append(allErrs, field.Forbidden(fldPath.Child("validation"), "disabled by feature-gate CustomResourceValidation"))
-	}
-
-	if utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) {
-		allErrs = append(allErrs, ValidateCustomResourceDefinitionSubresources(spec.Subresources, fldPath.Child("subresources"))...)
-	} else if spec.Subresources != nil {
-		allErrs = append(allErrs, field.Forbidden(fldPath.Child("subresources"), "disabled by feature-gate CustomResourceSubresources"))
-	}
+	allErrs = append(allErrs, ValidateCustomResourceDefinitionValidation(spec.Validation, hasAnyStatusEnabled(spec), fldPath.Child("validation"))...)
+	allErrs = append(allErrs, ValidateCustomResourceDefinitionSubresources(spec.Subresources, fldPath.Child("subresources"))...)
 
 	for i := range spec.AdditionalPrinterColumns {
 		if errs := ValidateCustomResourceColumnDefinition(&spec.AdditionalPrinterColumns[i], fldPath.Child("additionalPrinterColumns").Index(i)); len(errs) > 0 {
@@ -481,7 +471,7 @@ func ValidateCustomResourceDefinitionValidation(customResourceValidation *apiext
 	if schema := customResourceValidation.OpenAPIV3Schema; schema != nil {
 		// if the status subresource is enabled, only certain fields are allowed inside the root schema.
 		// these fields are chosen such that, if status is extracted as properties["status"], it's validation is not lost.
-		if utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) && statusSubresourceEnabled {
+		if statusSubresourceEnabled {
 			v := reflect.ValueOf(schema).Elem()
 			for i := 0; i < v.NumField(); i++ {
 				// skip zero values

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresourcedefinition/BUILD

 package(default_visibility = ["//visibility:public"])
 
-load(
-    "@io_bazel_rules_go//go:def.bzl",
-    "go_library",
-)
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 
 go_library(
     name = "go_default_library",
@@ -47,3 +44,16 @@ filegroup(
     srcs = [":package-srcs"],
     tags = ["automanaged"],
 )
+
+go_test(
+    name = "go_default_test",
+    srcs = ["strategy_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions:go_default_library",
+        "//staging/src/k8s.io/apiextensions-apiserver/pkg/features:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/util/diff:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/util/feature/testing:go_default_library",
+    ],
+)

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresourcedefinition/strategy.go

@@ -54,32 +54,7 @@ func (strategy) PrepareForCreate(ctx context.Context, obj runtime.Object) {
 	crd.Status = apiextensions.CustomResourceDefinitionStatus{}
 	crd.Generation = 1
 
-	// if the feature gate is disabled, drop the feature.
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceValidation) {
-		crd.Spec.Validation = nil
-		for i := range crd.Spec.Versions {
-			crd.Spec.Versions[i].Schema = nil
-		}
-	}
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) {
-		crd.Spec.Subresources = nil
-		for i := range crd.Spec.Versions {
-			crd.Spec.Versions[i].Subresources = nil
-		}
-	}
-	// On CREATE, if the CustomResourceWebhookConversion feature gate is off, we auto-clear
-	// the per-version fields. This is to be consistent with the other built-in types, as the
-	// apiserver drops unknown fields.
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) {
-		for i := range crd.Spec.Versions {
-			crd.Spec.Versions[i].Schema = nil
-			crd.Spec.Versions[i].Subresources = nil
-			crd.Spec.Versions[i].AdditionalPrinterColumns = nil
-		}
-	}
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) && crd.Spec.Conversion != nil {
-		crd.Spec.Conversion.WebhookClientConfig = nil
-	}
+	dropDisabledFields(&crd.Spec, nil)
 
 	for _, v := range crd.Spec.Versions {
 		if v.Storage {
@@ -109,45 +84,7 @@ func (strategy) PrepareForUpdate(ctx context.Context, obj, old runtime.Object) {
 		newCRD.Generation = oldCRD.Generation + 1
 	}
 
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceValidation) {
-		newCRD.Spec.Validation = nil
-		oldCRD.Spec.Validation = nil
-		for i := range newCRD.Spec.Versions {
-			newCRD.Spec.Versions[i].Schema = nil
-		}
-		for i := range oldCRD.Spec.Versions {
-			oldCRD.Spec.Versions[i].Schema = nil
-		}
-	}
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) {
-		newCRD.Spec.Subresources = nil
-		oldCRD.Spec.Subresources = nil
-		for i := range newCRD.Spec.Versions {
-			newCRD.Spec.Versions[i].Subresources = nil
-		}
-		for i := range oldCRD.Spec.Versions {
-			oldCRD.Spec.Versions[i].Subresources = nil
-		}
-	}
-
-	// On UPDATE, if the CustomResourceWebhookConversion feature gate is off, we auto-clear
-	// the per-version fields if the old CRD doesn't use per-version fields already.
-	// This is to be consistent with the other built-in types, as the apiserver drops unknown
-	// fields. If the old CRD already uses per-version fields, the CRD is allowed to continue
-	// use per-version fields.
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) &&
-		!hasPerVersionField(oldCRD.Spec.Versions) {
-		for i := range newCRD.Spec.Versions {
-			newCRD.Spec.Versions[i].Schema = nil
-			newCRD.Spec.Versions[i].Subresources = nil
-			newCRD.Spec.Versions[i].AdditionalPrinterColumns = nil
-		}
-	}
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) && newCRD.Spec.Conversion != nil {
-		if oldCRD.Spec.Conversion == nil || newCRD.Spec.Conversion.WebhookClientConfig == nil {
-			newCRD.Spec.Conversion.WebhookClientConfig = nil
-		}
-	}
+	dropDisabledFields(&newCRD.Spec, &oldCRD.Spec)
 
 	for _, v := range newCRD.Spec.Versions {
 		if v.Storage {
@@ -159,16 +96,6 @@ func (strategy) PrepareForUpdate(ctx context.Context, obj, old runtime.Object) {
 	}
 }
 
-// hasPerVersionField returns true if a CRD uses per-version schema/subresources/columns fields.
-func hasPerVersionField(versions []apiextensions.CustomResourceDefinitionVersion) bool {
-	for _, v := range versions {
-		if v.Schema != nil || v.Subresources != nil || len(v.AdditionalPrinterColumns) > 0 {
-			return true
-		}
-	}
-	return false
-}
-
 // Validate validates a new CustomResourceDefinition.
 func (strategy) Validate(ctx context.Context, obj runtime.Object) field.ErrorList {
 	return validation.ValidateCustomResourceDefinition(obj.(*apiextensions.CustomResourceDefinition))
@@ -259,3 +186,102 @@ func MatchCustomResourceDefinition(label labels.Selector, field fields.Selector)
 func CustomResourceDefinitionToSelectableFields(obj *apiextensions.CustomResourceDefinition) fields.Set {
 	return generic.ObjectMetaFieldsSet(&obj.ObjectMeta, true)
 }
+
+func dropDisabledFields(crdSpec, oldCrdSpec *apiextensions.CustomResourceDefinitionSpec) {
+	// if the feature gate is disabled, drop the feature.
+	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceValidation) &&
+		!validationInUse(oldCrdSpec) {
+		crdSpec.Validation = nil
+		for i := range crdSpec.Versions {
+			crdSpec.Versions[i].Schema = nil
+		}
+	}
+	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) &&
+		!subresourceInUse(oldCrdSpec) {
+		crdSpec.Subresources = nil
+		for i := range crdSpec.Versions {
+			crdSpec.Versions[i].Subresources = nil
+		}
+	}
+
+	// 1. On CREATE (in which case the old CRD spec is nil), if the CustomResourceWebhookConversion feature gate is off, we auto-clear
+	// the per-version fields. This is to be consistent with the other built-in types, as the
+	// apiserver drops unknown fields.
+	// 2. On UPDATE, if the CustomResourceWebhookConversion feature gate is off, we auto-clear
+	// the per-version fields if the old CRD doesn't use per-version fields already.
+	// This is to be consistent with the other built-in types, as the apiserver drops unknown
+	// fields. If the old CRD already uses per-version fields, the CRD is allowed to continue
+	// use per-version fields.
+	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) &&
+		!hasPerVersionField(oldCrdSpec) {
+		for i := range crdSpec.Versions {
+			crdSpec.Versions[i].Schema = nil
+			crdSpec.Versions[i].Subresources = nil
+			crdSpec.Versions[i].AdditionalPrinterColumns = nil
+		}
+	}
+
+	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceWebhookConversion) &&
+		!conversionWebhookInUse(oldCrdSpec) {
+		if crdSpec.Conversion != nil {
+			crdSpec.Conversion.WebhookClientConfig = nil
+		}
+	}
+
+}
+
+func validationInUse(crdSpec *apiextensions.CustomResourceDefinitionSpec) bool {
+	if crdSpec == nil {
+		return false
+	}
+	if crdSpec.Validation != nil {
+		return true
+	}
+
+	for i := range crdSpec.Versions {
+		if crdSpec.Versions[i].Schema != nil {
+			return true
+		}
+	}
+	return false
+}
+
+func subresourceInUse(crdSpec *apiextensions.CustomResourceDefinitionSpec) bool {
+	if crdSpec == nil {
+		return false
+	}
+	if crdSpec.Subresources != nil {
+		return true
+	}
+
+	for i := range crdSpec.Versions {
+		if crdSpec.Versions[i].Subresources != nil {
+			return true
+		}
+	}
+	return false
+}
+
+// hasPerVersionField returns true if a CRD uses per-version schema/subresources/columns fields.
+//func hasPerVersionField(versions []apiextensions.CustomResourceDefinitionVersion) bool {
+func hasPerVersionField(crdSpec *apiextensions.CustomResourceDefinitionSpec) bool {
+	if crdSpec == nil {
+		return false
+	}
+	for _, v := range crdSpec.Versions {
+		if v.Schema != nil || v.Subresources != nil || len(v.AdditionalPrinterColumns) > 0 {
+			return true
+		}
+	}
+	return false
+}
+
+func conversionWebhookInUse(crdSpec *apiextensions.CustomResourceDefinitionSpec) bool {
+	if crdSpec == nil {
+		return false
+	}
+	if crdSpec.Conversion == nil {
+		return false
+	}
+	return crdSpec.Conversion.WebhookClientConfig != nil
+}