Introduce storagebackend.ConfigForResource

This is a Config specialized for a GroupResource.
It will support generating new resource-specific metrics.

Kubernetes-commit: 85bcd243aa3c8769a5904a1aea44ce704f5e7174

pkg/registry/generic/options.go

@@ -26,9 +26,9 @@ import (
 	"k8s.io/client-go/tools/cache"
 )
 
-// RESTOptions is set of configuration options to generic registries.
+// RESTOptions is set of resource-specific configuration options to generic registries.
 type RESTOptions struct {
-	StorageConfig *storagebackend.Config
+	StorageConfig *storagebackend.ConfigForResource
 	Decorator     StorageDecorator
 
 	EnableGarbageCollection   bool

pkg/registry/generic/registry/dryrun_test.go

@@ -27,6 +27,7 @@ import (
 	"k8s.io/apimachinery/pkg/api/apitesting"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
 	examplev1 "k8s.io/apiserver/pkg/apis/example/v1"
 	"k8s.io/apiserver/pkg/registry/rest"
@@ -38,7 +39,7 @@ import (
 func NewDryRunnableTestStorage(t *testing.T) (DryRunnableStorage, func()) {
 	server, sc := etcd3testing.NewUnsecuredEtcd3TestClientServer(t)
 	sc.Codec = apitesting.TestStorageCodec(codecs, examplev1.SchemeGroupVersion)
-	s, destroy, err := factory.Create(*sc, nil)
+	s, destroy, err := factory.Create(*sc.ForResource(schema.GroupResource{Resource: "pods"}), nil)
 	if err != nil {
 		t.Fatalf("Error creating storage: %v", err)
 	}

pkg/registry/generic/registry/storage_factory.go

@@ -36,7 +36,7 @@ import (
 // Creates a cacher based given storageConfig.
 func StorageWithCacher() generic.StorageDecorator {
 	return func(
-		storageConfig *storagebackend.Config,
+		storageConfig *storagebackend.ConfigForResource,
 		resourcePrefix string,
 		keyFunc func(obj runtime.Object) (string, error),
 		newFunc func() runtime.Object,

pkg/registry/generic/registry/store_test.go

@@ -2230,7 +2230,7 @@ func newTestGenericStoreRegistry(t *testing.T, scheme *runtime.Scheme, hasCacheE
 	newListFunc := func() runtime.Object { return &example.PodList{} }
 
 	sc.Codec = apitesting.TestStorageCodec(codecs, examplev1.SchemeGroupVersion)
-	s, dFunc, err := factory.Create(*sc, newFunc)
+	s, dFunc, err := factory.Create(*sc.ForResource(schema.GroupResource{Resource: "pods"}), newFunc)
 	if err != nil {
 		t.Fatalf("Error creating storage: %v", err)
 	}

pkg/registry/generic/storage_decorator.go

@@ -27,7 +27,7 @@ import (
 // StorageDecorator is a function signature for producing a storage.Interface
 // and an associated DestroyFunc from given parameters.
 type StorageDecorator func(
-	config *storagebackend.Config,
+	config *storagebackend.ConfigForResource,
 	resourcePrefix string,
 	keyFunc func(obj runtime.Object) (string, error),
 	newFunc func() runtime.Object,
@@ -39,7 +39,7 @@ type StorageDecorator func(
 // UndecoratedStorage returns the given a new storage from the given config
 // without any decoration.
 func UndecoratedStorage(
-	config *storagebackend.Config,
+	config *storagebackend.ConfigForResource,
 	resourcePrefix string,
 	keyFunc func(obj runtime.Object) (string, error),
 	newFunc func() runtime.Object,
@@ -53,6 +53,6 @@ func UndecoratedStorage(
 // NewRawStorage creates the low level kv storage. This is a work-around for current
 // two layer of same storage interface.
 // TODO: Once cacher is enabled on all registries (event registry is special), we will remove this method.
-func NewRawStorage(config *storagebackend.Config, newFunc func() runtime.Object) (storage.Interface, factory.DestroyFunc, error) {
+func NewRawStorage(config *storagebackend.ConfigForResource, newFunc func() runtime.Object) (storage.Interface, factory.DestroyFunc, error) {
 	return factory.Create(*config, newFunc)
 }

pkg/server/options/etcd.go

@@ -255,7 +255,7 @@ type SimpleRestOptionsFactory struct {
 
 func (f *SimpleRestOptionsFactory) GetRESTOptions(resource schema.GroupResource) (generic.RESTOptions, error) {
 	ret := generic.RESTOptions{
-		StorageConfig:             &f.Options.StorageConfig,
+		StorageConfig:             f.Options.StorageConfig.ForResource(resource),
 		Decorator:                 generic.UndecoratedStorage,
 		EnableGarbageCollection:   f.Options.EnableGarbageCollection,
 		DeleteCollectionWorkers:   f.Options.DeleteCollectionWorkers,

pkg/server/storage/storage_factory.go

@@ -46,7 +46,7 @@ type Backend struct {
 type StorageFactory interface {
 	// New finds the storage destination for the given group and resource. It will
 	// return an error if the group has no storage destination configured.
-	NewConfig(groupResource schema.GroupResource) (*storagebackend.Config, error)
+	NewConfig(groupResource schema.GroupResource) (*storagebackend.ConfigForResource, error)
 
 	// ResourcePrefix returns the overridden resource prefix for the GroupResource
 	// This allows for cohabitation of resources with different native types and provides
@@ -250,7 +250,7 @@ func (s *DefaultStorageFactory) getStorageGroupResource(groupResource schema.Gro
 
 // New finds the storage destination for the given group and resource. It will
 // return an error if the group has no storage destination configured.
-func (s *DefaultStorageFactory) NewConfig(groupResource schema.GroupResource) (*storagebackend.Config, error) {
+func (s *DefaultStorageFactory) NewConfig(groupResource schema.GroupResource) (*storagebackend.ConfigForResource, error) {
 	chosenStorageResource := s.getStorageGroupResource(groupResource)
 
 	// operate on copy
@@ -284,7 +284,7 @@ func (s *DefaultStorageFactory) NewConfig(groupResource schema.GroupResource) (*
 	}
 	klog.V(3).Infof("storing %v in %v, reading as %v from %#v", groupResource, codecConfig.StorageVersion, codecConfig.MemoryVersion, codecConfig.Config)
 
-	return &storageConfig, nil
+	return storageConfig.ForResource(groupResource), nil
 }
 
 // Backends returns all backends for all registered storage destinations.

pkg/storage/storagebackend/config.go

@@ -21,6 +21,7 @@ import (
 
 	"go.opentelemetry.io/otel/trace"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/server/egressselector"
 	"k8s.io/apiserver/pkg/storage/etcd3"
 	"k8s.io/apiserver/pkg/storage/value"
@@ -91,6 +92,23 @@ type Config struct {
 	StorageObjectCountTracker flowcontrolrequest.StorageObjectCountTracker
 }
 
+// ConfigForResource is a Config specialized to a particular `schema.GroupResource`
+type ConfigForResource struct {
+	// Config is the resource-independent configuration
+	Config
+
+	// GroupResource is the relevant one
+	GroupResource schema.GroupResource
+}
+
+// ForResource specializes to the given resource
+func (config *Config) ForResource(resource schema.GroupResource) *ConfigForResource {
+	return &ConfigForResource{
+		Config:        *config,
+		GroupResource: resource,
+	}
+}
+
 func NewDefaultConfig(prefix string, codec runtime.Codec) *Config {
 	return &Config{
 		Paging:               true,

pkg/storage/storagebackend/factory/etcd3.go

@@ -244,7 +244,7 @@ func startCompactorOnce(c storagebackend.TransportConfig, interval time.Duration
 	}, nil
 }
 
-func newETCD3Storage(c storagebackend.Config, newFunc func() runtime.Object) (storage.Interface, DestroyFunc, error) {
+func newETCD3Storage(c storagebackend.ConfigForResource, newFunc func() runtime.Object) (storage.Interface, DestroyFunc, error) {
 	stopCompactor, err := startCompactorOnce(c.Transport, c.CompactionInterval)
 	if err != nil {
 		return nil, nil, err

pkg/storage/storagebackend/factory/factory.go

@@ -28,7 +28,7 @@ import (
 type DestroyFunc func()
 
 // Create creates a storage backend based on given config.
-func Create(c storagebackend.Config, newFunc func() runtime.Object) (storage.Interface, DestroyFunc, error) {
+func Create(c storagebackend.ConfigForResource, newFunc func() runtime.Object) (storage.Interface, DestroyFunc, error) {
 	switch c.Type {
 	case storagebackend.StorageTypeETCD2:
 		return nil, nil, fmt.Errorf("%s is no longer a supported storage backend", c.Type)

pkg/storage/storagebackend/factory/tls_test.go

@@ -29,6 +29,7 @@ import (
 	apitesting "k8s.io/apimachinery/pkg/api/apitesting"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apiserver/pkg/apis/example"
@@ -78,7 +79,7 @@ func TestTLSConnection(t *testing.T) {
 		},
 		Codec: codec,
 	}
-	storage, destroyFunc, err := newETCD3Storage(cfg, nil)
+	storage, destroyFunc, err := newETCD3Storage(*cfg.ForResource(schema.GroupResource{Resource: "pods"}), nil)
 	defer destroyFunc()
 	if err != nil {
 		t.Fatal(err)