Merge pull request #66512 from jennybuckley/openapi-ignore-prefix

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Skip building openapi for ignored paths

alternative to #66286

/kind bug
Fixes #66285

```release-note
NONE
```

staging/src/k8s.io/apiserver/pkg/endpoints/BUILD

@@ -85,6 +85,8 @@ go_library(
         "//vendor/github.com/emicklei/go-restful:go_default_library",
         "//vendor/k8s.io/kube-openapi/pkg/builder:go_default_library",
         "//vendor/k8s.io/kube-openapi/pkg/common:go_default_library",
+        "//vendor/k8s.io/kube-openapi/pkg/util:go_default_library",
+        "//vendor/k8s.io/kube-openapi/pkg/util/proto:go_default_library",
     ],
 )
 

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

@@ -41,6 +41,8 @@ import (
 	genericfilters "k8s.io/apiserver/pkg/server/filters"
 	utilopenapi "k8s.io/apiserver/pkg/util/openapi"
 	openapibuilder "k8s.io/kube-openapi/pkg/builder"
+	openapiutil "k8s.io/kube-openapi/pkg/util"
+	openapiproto "k8s.io/kube-openapi/pkg/util/proto"
 )
 
 const (
@@ -498,16 +500,10 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 	if a.group.MetaGroupVersion != nil {
 		reqScope.MetaGroupVersion = *a.group.MetaGroupVersion
 	}
-	if a.group.OpenAPIConfig != nil {
+	reqScope.OpenAPISchema, err = a.getOpenAPISchema(ws.RootPath(), resource, fqKindToRegister, defaultVersionedObject)
-		openAPIDefinitions, err := openapibuilder.BuildOpenAPIDefinitionsForResource(defaultVersionedObject, a.group.OpenAPIConfig)
-		if err != nil {
-			return nil, fmt.Errorf("unable to build openapi definitions for %v: %v", fqKindToRegister, err)
-		}
-		reqScope.OpenAPISchema, err = utilopenapi.ToProtoSchema(openAPIDefinitions, fqKindToRegister)
 	if err != nil {
 		return nil, fmt.Errorf("unable to get openapi schema for %v: %v", fqKindToRegister, err)
 	}
-	}
 	for _, action := range actions {
 		producedObject := storageMeta.ProducesObject(action.Verb)
 		if producedObject == nil {
@@ -852,6 +848,24 @@ func (a *APIInstaller) registerResourceHandlers(path string, storage rest.Storag
 	return &apiResource, nil
 }
 
+// getOpenAPISchema builds the openapi schema for a single resource model to be given to each handler. It will
+// return nil if the apiserver doesn't have openapi enabled, or if the specific path should be ignored by openapi.
+func (a *APIInstaller) getOpenAPISchema(rootPath, resource string, kind schema.GroupVersionKind, sampleObject interface{}) (openapiproto.Schema, error) {
+	path := gpath.Join(rootPath, resource)
+	if a.group.OpenAPIConfig == nil {
+		return nil, nil
+	}
+	pathsToIgnore := openapiutil.NewTrie(a.group.OpenAPIConfig.IgnorePrefixes)
+	if pathsToIgnore.HasPrefix(path) {
+		return nil, nil
+	}
+	openAPIDefinitions, err := openapibuilder.BuildOpenAPIDefinitionsForResource(sampleObject, a.group.OpenAPIConfig)
+	if err != nil {
+		return nil, err
+	}
+	return utilopenapi.ToProtoSchema(openAPIDefinitions, kind)
+}
+
 // indirectArbitraryPointer returns *ptrToObject for an arbitrary pointer
 func indirectArbitraryPointer(ptrToObject interface{}) interface{} {
 	return reflect.Indirect(reflect.ValueOf(ptrToObject)).Interface()