Automated cherry pick of #58438: fix apiserver crash caused by nil pointer and ensure CRD #58914: fix GetCustomResourceListerCollectionDeleter comments

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

@@ -11,8 +11,8 @@ go_library(
     srcs = ["validation.go"],
     importpath = "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation",
     deps = [
-        "//vendor/github.com/go-openapi/spec:go_default_library",
         "//vendor/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions:go_default_library",
+        "//vendor/k8s.io/apiextensions-apiserver/pkg/apiserver/validation:go_default_library",
         "//vendor/k8s.io/apiextensions-apiserver/pkg/features:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/validation:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation:go_default_library",

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

@@ -20,14 +20,13 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/go-openapi/spec"
-
 	genericvalidation "k8s.io/apimachinery/pkg/api/validation"
 	validationutil "k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 
 	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions"
+	apiservervalidation "k8s.io/apiextensions-apiserver/pkg/apiserver/validation"
 	apiextensionsfeatures "k8s.io/apiextensions-apiserver/pkg/features"
 )
 
@@ -188,6 +187,12 @@ func ValidateCustomResourceDefinitionValidation(customResourceValidation *apiext
 		allErrs = append(allErrs, ValidateCustomResourceDefinitionOpenAPISchema(customResourceValidation.OpenAPIV3Schema, fldPath.Child("openAPIV3Schema"), openAPIV3Schema)...)
 	}
 
+	// if validation passed otherwise, make sure we can actually construct a schema validator from this custom resource validation.
+	if len(allErrs) == 0 {
+		if _, err := apiservervalidation.NewSchemaValidator(customResourceValidation); err != nil {
+			allErrs = append(allErrs, field.Invalid(fldPath, "", fmt.Sprintf("error building validator: %v", err)))
+		}
+	}
 	return allErrs
 }
 
@@ -213,17 +218,6 @@ func ValidateCustomResourceDefinitionOpenAPISchema(schema *apiextensions.JSONSch
 		allErrs = append(allErrs, ValidateCustomResourceDefinitionOpenAPISchema(schema.AdditionalProperties.Schema, fldPath.Child("additionalProperties"), ssv)...)
 	}
 
-	if schema.Ref != nil {
-		openapiRef, err := spec.NewRef(*schema.Ref)
-		if err != nil {
-			allErrs = append(allErrs, field.Invalid(fldPath.Child("ref"), *schema.Ref, err.Error()))
-		}
-
-		if !openapiRef.IsValidURI() {
-			allErrs = append(allErrs, field.Invalid(fldPath.Child("ref"), *schema.Ref, "ref does not point to a valid URI"))
-		}
-	}
-
 	if schema.AdditionalItems != nil {
 		allErrs = append(allErrs, ValidateCustomResourceDefinitionOpenAPISchema(schema.AdditionalItems.Schema, fldPath.Child("additionalItems"), ssv)...)
 	}
@@ -318,6 +312,10 @@ func (v *specStandardValidatorV3) validate(schema *apiextensions.JSONSchemaProps
 		allErrs = append(allErrs, field.Forbidden(fldPath.Child("dependencies"), "dependencies is not supported"))
 	}
 
+	if schema.Ref != nil {
+		allErrs = append(allErrs, field.Forbidden(fldPath.Child("$ref"), "$ref is not supported"))
+	}
+
 	if schema.Type == "null" {
 		allErrs = append(allErrs, field.Forbidden(fldPath.Child("type"), "type cannot be set to null"))
 	}

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

@@ -16,9 +16,6 @@ go_library(
     ],
     importpath = "k8s.io/apiextensions-apiserver/pkg/apiserver",
     deps = [
-        "//vendor/github.com/go-openapi/spec:go_default_library",
-        "//vendor/github.com/go-openapi/strfmt:go_default_library",
-        "//vendor/github.com/go-openapi/validate:go_default_library",
         "//vendor/github.com/golang/glog:go_default_library",
         "//vendor/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions:go_default_library",
         "//vendor/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/install:go_default_library",

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

@@ -25,9 +25,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	openapispec "github.com/go-openapi/spec"
-	"github.com/go-openapi/strfmt"
-	"github.com/go-openapi/validate"
 	"github.com/golang/glog"
 
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
@@ -275,14 +272,14 @@ func (r *crdHandler) removeDeadStorage() {
 	r.customStorage.Store(storageMap)
 }
 
-// GetCustomResourceListerCollectionDeleter returns the ListerCollectionDeleter for
-// the given uid, or nil if one does not exist.
-func (r *crdHandler) GetCustomResourceListerCollectionDeleter(crd *apiextensions.CustomResourceDefinition) finalizer.ListerCollectionDeleter {
+// GetCustomResourceListerCollectionDeleter returns the ListerCollectionDeleter of
+// the given crd.
+func (r *crdHandler) GetCustomResourceListerCollectionDeleter(crd *apiextensions.CustomResourceDefinition) (finalizer.ListerCollectionDeleter, error) {
 	info, err := r.getServingInfoFor(crd)
 	if err != nil {
-		utilruntime.HandleError(err)
+		return nil, err
 	}
-	return info.storage
+	return info.storage, nil
 }
 
 func (r *crdHandler) getServingInfoFor(crd *apiextensions.CustomResourceDefinition) (*crdInfo, error) {
@@ -318,15 +315,10 @@ func (r *crdHandler) getServingInfoFor(crd *apiextensions.CustomResourceDefiniti
 	}
 	creator := unstructuredCreator{}
 
-	// convert CRD schema to openapi schema
-	openapiSchema := &openapispec.Schema{}
-	if err := apiservervalidation.ConvertToOpenAPITypes(crd, openapiSchema); err != nil {
-		return nil, err
-	}
-	if err := openapispec.ExpandSchema(openapiSchema, nil, nil); err != nil {
+	validator, err := apiservervalidation.NewSchemaValidator(crd.Spec.Validation)
+	if err != nil {
 		return nil, err
 	}
-	validator := validate.NewSchemaValidator(openapiSchema, nil, "", strfmt.Default)
 
 	storage := customresource.NewREST(
 		schema.GroupResource{Group: crd.Spec.Group, Resource: crd.Status.AcceptedNames.Plural},

staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/validation/BUILD

@@ -12,6 +12,7 @@ go_library(
     importpath = "k8s.io/apiextensions-apiserver/pkg/apiserver/validation",
     deps = [
         "//vendor/github.com/go-openapi/spec:go_default_library",
+        "//vendor/github.com/go-openapi/strfmt:go_default_library",
         "//vendor/github.com/go-openapi/validate:go_default_library",
         "//vendor/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions:go_default_library",
     ],

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

@@ -18,11 +18,24 @@ package validation
 
 import (
 	"github.com/go-openapi/spec"
+	"github.com/go-openapi/strfmt"
 	"github.com/go-openapi/validate"
 
 	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions"
 )
 
+// NewSchemaValidator creates an openapi schema validator for the given CRD validation.
+func NewSchemaValidator(customResourceValidation *apiextensions.CustomResourceValidation) (*validate.SchemaValidator, error) {
+	// Convert CRD schema to openapi schema
+	openapiSchema := &spec.Schema{}
+	if customResourceValidation != nil {
+		if err := convertJSONSchemaProps(customResourceValidation.OpenAPIV3Schema, openapiSchema); err != nil {
+			return nil, err
+		}
+	}
+	return validate.NewSchemaValidator(openapiSchema, nil, "", strfmt.Default), nil
+}
+
 // ValidateCustomResource validates the Custom Resource against the schema in the CustomResourceDefinition.
 // CustomResource is a JSON data structure.
 func ValidateCustomResource(customResource interface{}, validator *validate.SchemaValidator) error {
@@ -33,16 +46,6 @@ func ValidateCustomResource(customResource interface{}, validator *validate.Sche
 	return nil
 }
 
-// ConvertToOpenAPITypes is used to convert internal types to go-openapi types.
-func ConvertToOpenAPITypes(in *apiextensions.CustomResourceDefinition, out *spec.Schema) error {
-	if in.Spec.Validation != nil {
-		if err := convertJSONSchemaProps(in.Spec.Validation.OpenAPIV3Schema, out); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
 func convertJSONSchemaProps(in *apiextensions.JSONSchemaProps, out *spec.Schema) error {
 	if in == nil {
 		return nil

staging/src/k8s.io/apiextensions-apiserver/pkg/controller/finalizer/crd_finalizer.go

@@ -65,7 +65,7 @@ type ListerCollectionDeleter interface {
 type CRClientGetter interface {
 	// GetCustomResourceListerCollectionDeleter gets the ListerCollectionDeleter for the given CRD
 	// UID.
-	GetCustomResourceListerCollectionDeleter(crd *apiextensions.CustomResourceDefinition) ListerCollectionDeleter
+	GetCustomResourceListerCollectionDeleter(crd *apiextensions.CustomResourceDefinition) (ListerCollectionDeleter, error)
 }
 
 // NewCRDFinalizer creates a new CRDFinalizer.
@@ -155,9 +155,9 @@ func (c *CRDFinalizer) deleteInstances(crd *apiextensions.CustomResourceDefiniti
 	// Now we can start deleting items. While it would be ideal to use a REST API client, doing so
 	// could incorrectly delete a ThirdPartyResource with the same URL as the CustomResource, so we go
 	// directly to the storage instead. Since we control the storage, we know that delete collection works.
-	crClient := c.crClientGetter.GetCustomResourceListerCollectionDeleter(crd)
-	if crClient == nil {
-		err := fmt.Errorf("unable to find a custom resource client for %s.%s", crd.Status.AcceptedNames.Plural, crd.Spec.Group)
+	crClient, err := c.crClientGetter.GetCustomResourceListerCollectionDeleter(crd)
+	if err != nil {
+		err = fmt.Errorf("unable to find a custom resource client for %s.%s: %v", crd.Status.AcceptedNames.Plural, crd.Spec.Group, err)
 		return apiextensions.CustomResourceDefinitionCondition{
 			Type:    apiextensions.Terminating,
 			Status:  apiextensions.ConditionTrue,

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

@@ -403,16 +403,23 @@ func TestForbiddenFieldsInSchema(t *testing.T) {
 		t.Fatalf("unexpected non-error: uniqueItems cannot be set to true")
 	}
 
+	noxuDefinition.Spec.Validation.OpenAPIV3Schema.Ref = strPtr("#/definition/zeta")
 	noxuDefinition.Spec.Validation.OpenAPIV3Schema.Properties["zeta"] = apiextensionsv1beta1.JSONSchemaProps{
 		Type:        "array",
 		UniqueItems: false,
 	}
 
+	_, err = testserver.CreateNewCustomResourceDefinition(noxuDefinition, apiExtensionClient, clientPool)
+	if err == nil {
+		t.Fatal("unexpected non-error: $ref cannot be non-empty string")
+	}
+
+	noxuDefinition.Spec.Validation.OpenAPIV3Schema.Ref = nil
+
 	_, err = testserver.CreateNewCustomResourceDefinition(noxuDefinition, apiExtensionClient, clientPool)
 	if err != nil {
 		t.Fatal(err)
 	}
-
 }
 
 func float64Ptr(f float64) *float64 {
@@ -422,3 +429,7 @@ func float64Ptr(f float64) *float64 {
 func int64Ptr(f int64) *int64 {
 	return &f
 }
+
+func strPtr(str string) *string {
+	return &str
+}