Merge pull request #37505 from k82cn/use_controller_inf

Automatic merge from submit-queue (batch tested with PRs 39807, 37505, 39844, 39525, 39109)

Made cache.Controller to be interface.

**What this PR does / why we need it**:

#37504

federation/pkg/federation-controller/cluster/clustercontroller.go

@@ -49,7 +49,7 @@ type ClusterController struct {
 	clusterKubeClientMap map[string]ClusterClient
 
 	// cluster framework and store
-	clusterController *cache.Controller
+	clusterController cache.Controller
 	clusterStore      clustercache.StoreToClusterLister
 }
 

federation/pkg/federation-controller/configmap/configmap_controller.go

@@ -58,7 +58,7 @@ type ConfigMapController struct {
 	// Definitions of configmaps that should be federated.
 	configmapInformerStore cache.Store
 	// Informer controller for configmaps that should be federated.
-	configmapInformerController cache.ControllerInterface
+	configmapInformerController cache.Controller
 
 	// Client to federated api server.
 	federatedApiClient federationclientset.Interface
@@ -112,7 +112,7 @@ func NewConfigMapController(client federationclientset.Interface) *ConfigMapCont
 	// Federated informer on configmaps in members of federation.
 	configmapcontroller.configmapFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			return cache.NewInformer(
 				&cache.ListWatch{
 					ListFunc: func(options apiv1.ListOptions) (pkgruntime.Object, error) {

federation/pkg/federation-controller/daemonset/daemonset_controller.go

@@ -63,7 +63,7 @@ type DaemonSetController struct {
 	// Definitions of daemonsets that should be federated.
 	daemonsetInformerStore cache.Store
 	// Informer controller for daemonsets that should be federated.
-	daemonsetInformerController cache.ControllerInterface
+	daemonsetInformerController cache.Controller
 
 	// Client to federated api server.
 	federatedApiClient federationclientset.Interface
@@ -119,7 +119,7 @@ func NewDaemonSetController(client federationclientset.Interface) *DaemonSetCont
 	// Federated informer on daemonsets in members of federation.
 	daemonsetcontroller.daemonsetFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			return cache.NewInformer(
 				&cache.ListWatch{
 					ListFunc: func(options apiv1.ListOptions) (pkgruntime.Object, error) {

federation/pkg/federation-controller/deployment/deploymentcontroller.go

@@ -80,7 +80,7 @@ func parseFederationDeploymentPreference(fd *extensionsv1.Deployment) (*fed.Fede
 type DeploymentController struct {
 	fedClient fedclientset.Interface
 
-	deploymentController *cache.Controller
+	deploymentController cache.Controller
 	deploymentStore      cache.Store
 
 	fedDeploymentInformer fedutil.FederatedInformer
@@ -119,7 +119,7 @@ func NewDeploymentController(federationClient fedclientset.Interface) *Deploymen
 		eventRecorder: recorder,
 	}
 
-	deploymentFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	deploymentFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {
@@ -146,7 +146,7 @@ func NewDeploymentController(federationClient fedclientset.Interface) *Deploymen
 	}
 	fdc.fedDeploymentInformer = fedutil.NewFederatedInformer(federationClient, deploymentFedInformerFactory, &clusterLifecycle)
 
-	podFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	podFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {

federation/pkg/federation-controller/ingress/ingress_controller.go

@@ -91,7 +91,7 @@ type IngressController struct {
 	// Definitions of ingresses that should be federated.
 	ingressInformerStore cache.Store
 	// Informer controller for ingresses that should be federated.
-	ingressInformerController cache.ControllerInterface
+	ingressInformerController cache.Controller
 
 	// Client to federated api server.
 	federatedApiClient federationclientset.Interface
@@ -157,7 +157,7 @@ func NewIngressController(client federationclientset.Interface) *IngressControll
 	// Federated informer on ingresses in members of federation.
 	ic.ingressFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			return cache.NewInformer(
 				&cache.ListWatch{
 					ListFunc: func(options v1.ListOptions) (pkgruntime.Object, error) {
@@ -189,7 +189,7 @@ func NewIngressController(client federationclientset.Interface) *IngressControll
 	// Federated informer on configmaps for ingress controllers in members of the federation.
 	ic.configMapFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			glog.V(4).Infof("Returning new informer for cluster %q", cluster.Name)
 			return cache.NewInformer(
 				&cache.ListWatch{

federation/pkg/federation-controller/namespace/namespace_controller.go

@@ -60,7 +60,7 @@ type NamespaceController struct {
 	// Definitions of namespaces that should be federated.
 	namespaceInformerStore cache.Store
 	// Informer controller for namespaces that should be federated.
-	namespaceInformerController cache.ControllerInterface
+	namespaceInformerController cache.Controller
 
 	// Client to federated api server.
 	federatedApiClient federationclientset.Interface
@@ -116,7 +116,7 @@ func NewNamespaceController(client federationclientset.Interface) *NamespaceCont
 	// Federated informer on namespaces in members of federation.
 	nc.namespaceFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			return cache.NewInformer(
 				&cache.ListWatch{
 					ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {

federation/pkg/federation-controller/replicaset/replicasetcontroller.go

@@ -80,7 +80,7 @@ func parseFederationReplicaSetReference(frs *extensionsv1.ReplicaSet) (*fed.Fede
 type ReplicaSetController struct {
 	fedClient fedclientset.Interface
 
-	replicaSetController *cache.Controller
+	replicaSetController cache.Controller
 	replicaSetStore      cache.StoreToReplicaSetLister
 
 	fedReplicaSetInformer fedutil.FederatedInformer
@@ -121,7 +121,7 @@ func NewReplicaSetController(federationClient fedclientset.Interface) *ReplicaSe
 		eventRecorder: recorder,
 	}
 
-	replicaSetFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	replicaSetFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {
@@ -148,7 +148,7 @@ func NewReplicaSetController(federationClient fedclientset.Interface) *ReplicaSe
 	}
 	frsc.fedReplicaSetInformer = fedutil.NewFederatedInformer(federationClient, replicaSetFedInformerFactory, &clusterLifecycle)
 
-	podFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	podFedInformerFactory := func(cluster *fedv1.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {

federation/pkg/federation-controller/secret/secret_controller.go

@@ -61,7 +61,7 @@ type SecretController struct {
 	// Definitions of secrets that should be federated.
 	secretInformerStore cache.Store
 	// Informer controller for secrets that should be federated.
-	secretInformerController cache.ControllerInterface
+	secretInformerController cache.Controller
 
 	// Client to federated api server.
 	federatedApiClient federationclientset.Interface
@@ -117,7 +117,7 @@ func NewSecretController(client federationclientset.Interface) *SecretController
 	// Federated informer on secrets in members of federation.
 	secretcontroller.secretFederatedInformer = util.NewFederatedInformer(
 		client,
-		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+		func(cluster *federationapi.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 			return cache.NewInformer(
 				&cache.ListWatch{
 					ListFunc: func(options apiv1.ListOptions) (pkgruntime.Object, error) {

federation/pkg/federation-controller/service/cluster_helper.go

@@ -41,11 +41,11 @@ type clusterCache struct {
 	// A store of services, populated by the serviceController
 	serviceStore cache.StoreToServiceLister
 	// Watches changes to all services
-	serviceController *cache.Controller
+	serviceController cache.Controller
 	// A store of endpoint, populated by the serviceController
 	endpointStore cache.StoreToEndpointsLister
 	// Watches changes to all endpoints
-	endpointController *cache.Controller
+	endpointController cache.Controller
 	// services that need to be synced
 	serviceQueue *workqueue.Type
 	// endpoints that need to be synced

federation/pkg/federation-controller/service/servicecontroller.go

@@ -121,12 +121,12 @@ type ServiceController struct {
 	// A store of services, populated by the serviceController
 	serviceStore cache.StoreToServiceLister
 	// Watches changes to all services
-	serviceController *cache.Controller
+	serviceController cache.Controller
 	federatedInformer fedutil.FederatedInformer
 	// A store of services, populated by the serviceController
 	clusterStore federationcache.StoreToClusterLister
 	// Watches changes to all services
-	clusterController *cache.Controller
+	clusterController cache.Controller
 	eventBroadcaster  record.EventBroadcaster
 	eventRecorder     record.EventRecorder
 	// services that need to be synced
@@ -245,7 +245,7 @@ func New(federationClient fedclientset.Interface, dns dnsprovider.Interface,
 			s.clusterDeliverer.DeliverAfter(allClustersKey, nil, clusterAvailableDelay)
 		},
 	}
-	fedInformerFactory := func(cluster *v1beta1.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	fedInformerFactory := func(cluster *v1beta1.Cluster, targetClient kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options v1.ListOptions) (pkgruntime.Object, error) {

federation/pkg/federation-controller/util/federated_informer.go

@@ -116,7 +116,7 @@ type FederatedInformerForTestOnly interface {
 
 // A function that should be used to create an informer on the target object. Store should use
 // cache.DeletionHandlingMetaNamespaceKeyFunc as a keying function.
-type TargetInformerFactory func(*federationapi.Cluster, kubeclientset.Interface) (cache.Store, cache.ControllerInterface)
+type TargetInformerFactory func(*federationapi.Cluster, kubeclientset.Interface) (cache.Store, cache.Controller)
 
 // A structure with cluster lifecycle handler functions. Cluster is available (and ClusterAvailable is fired)
 // when it is created in federated etcd and ready. Cluster becomes unavailable (and ClusterUnavailable is fired)
@@ -242,7 +242,7 @@ func isClusterReady(cluster *federationapi.Cluster) bool {
 }
 
 type informer struct {
-	controller cache.ControllerInterface
+	controller cache.Controller
 	store      cache.Store
 	stopChan   chan struct{}
 }

federation/pkg/federation-controller/util/federated_informer_test.go

@@ -77,7 +77,7 @@ func TestFederatedInformer(t *testing.T) {
 		return true, watch.NewFake(), nil
 	})
 
-	targetInformerFactory := func(cluster *federationapi.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.ControllerInterface) {
+	targetInformerFactory := func(cluster *federationapi.Cluster, clientset kubeclientset.Interface) (cache.Store, cache.Controller) {
 		return cache.NewInformer(
 			&cache.ListWatch{
 				ListFunc: func(options apiv1.ListOptions) (runtime.Object, error) {

pkg/client/cache/controller.go

@@ -61,21 +61,21 @@ type Config struct {
 type ProcessFunc func(obj interface{}) error
 
 // Controller is a generic controller framework.
-type Controller struct {
+type controller struct {
 	config         Config
 	reflector      *Reflector
 	reflectorMutex sync.RWMutex
 }
 
-// TODO make the "Controller" private, and convert all references to use ControllerInterface instead
+type Controller interface {
-type ControllerInterface interface {
 	Run(stopCh <-chan struct{})
 	HasSynced() bool
+	LastSyncResourceVersion() string
 }
 
 // New makes a new Controller from the given Config.
-func New(c *Config) *Controller {
+func New(c *Config) Controller {
-	ctlr := &Controller{
+	ctlr := &controller{
 		config: *c,
 	}
 	return ctlr
@@ -84,7 +84,7 @@ func New(c *Config) *Controller {
 // Run begins processing items, and will continue until a value is sent down stopCh.
 // It's an error to call Run more than once.
 // Run blocks; call via go.
-func (c *Controller) Run(stopCh <-chan struct{}) {
+func (c *controller) Run(stopCh <-chan struct{}) {
 	defer utilruntime.HandleCrash()
 	r := NewReflector(
 		c.config.ListerWatcher,
@@ -103,18 +103,15 @@ func (c *Controller) Run(stopCh <-chan struct{}) {
 }
 
 // Returns true once this controller has completed an initial resource listing
-func (c *Controller) HasSynced() bool {
+func (c *controller) HasSynced() bool {
 	return c.config.Queue.HasSynced()
 }
 
-// Requeue adds the provided object back into the queue if it does not already exist.
+func (c *controller) LastSyncResourceVersion() string {
-func (c *Controller) Requeue(obj interface{}) error {
+	if c.reflector == nil {
-	return c.config.Queue.AddIfNotPresent(Deltas{
+		return ""
-		Delta{
+	}
-			Type:   Sync,
+	return c.reflector.LastSyncResourceVersion()
-			Object: obj,
-		},
-	})
 }
 
 // processLoop drains the work queue.
@@ -126,7 +123,7 @@ func (c *Controller) Requeue(obj interface{}) error {
 // actually exit when the controller is stopped. Or just give up on this stuff
 // ever being stoppable. Converting this whole package to use Context would
 // also be helpful.
-func (c *Controller) processLoop() {
+func (c *controller) processLoop() {
 	for {
 		obj, err := c.config.Queue.Pop(PopProcessFunc(c.config.Process))
 		if err != nil {
@@ -218,7 +215,7 @@ func NewInformer(
 	objType runtime.Object,
 	resyncPeriod time.Duration,
 	h ResourceEventHandler,
-) (Store, *Controller) {
+) (Store, Controller) {
 	// This will hold the client state, as we know it.
 	clientState := NewStore(DeletionHandlingMetaNamespaceKeyFunc)
 
@@ -284,7 +281,7 @@ func NewIndexerInformer(
 	resyncPeriod time.Duration,
 	h ResourceEventHandler,
 	indexers Indexers,
-) (Indexer, *Controller) {
+) (Indexer, Controller) {
 	// This will hold the client state, as we know it.
 	clientState := NewIndexer(DeletionHandlingMetaNamespaceKeyFunc, indexers)
 

pkg/client/cache/shared_informer.go

@@ -43,7 +43,7 @@ type SharedInformer interface {
 	AddEventHandler(handler ResourceEventHandler) error
 	GetStore() Store
 	// GetController gives back a synthetic interface that "votes" to start the informer
-	GetController() ControllerInterface
+	GetController() Controller
 	Run(stopCh <-chan struct{})
 	HasSynced() bool
 	LastSyncResourceVersion() string
@@ -108,7 +108,7 @@ func WaitForCacheSync(stopCh <-chan struct{}, cacheSyncs ...InformerSynced) bool
 
 type sharedIndexInformer struct {
 	indexer    Indexer
-	controller *Controller
+	controller Controller
 
 	processor             *sharedProcessor
 	cacheMutationDetector CacheMutationDetector
@@ -145,6 +145,10 @@ func (v *dummyController) HasSynced() bool {
 	return v.informer.HasSynced()
 }
 
+func (c *dummyController) LastSyncResourceVersion() string {
+	return ""
+}
+
 type updateNotification struct {
 	oldObj interface{}
 	newObj interface{}
@@ -207,10 +211,10 @@ func (s *sharedIndexInformer) LastSyncResourceVersion() string {
 	s.startedLock.Lock()
 	defer s.startedLock.Unlock()
 
-	if s.controller == nil || s.controller.reflector == nil {
+	if s.controller == nil {
 		return ""
 	}
-	return s.controller.reflector.LastSyncResourceVersion()
+	return s.controller.LastSyncResourceVersion()
 }
 
 func (s *sharedIndexInformer) GetStore() Store {
@@ -232,7 +236,7 @@ func (s *sharedIndexInformer) AddIndexers(indexers Indexers) error {
 	return s.indexer.AddIndexers(indexers)
 }
 
-func (s *sharedIndexInformer) GetController() ControllerInterface {
+func (s *sharedIndexInformer) GetController() Controller {
 	return &dummyController{informer: s}
 }
 

pkg/controller/certificates/certificate_controller.go

@@ -48,7 +48,7 @@ type CertificateController struct {
 	kubeClient clientset.Interface
 
 	// CSR framework and store
-	csrController *cache.Controller
+	csrController cache.Controller
 	csrStore      cache.StoreToCertificateRequestLister
 
 	syncHandler func(csrKey string) error

pkg/controller/disruption/disruption.go

@@ -63,26 +63,26 @@ type DisruptionController struct {
 	kubeClient clientset.Interface
 
 	pdbStore      cache.Store
-	pdbController *cache.Controller
+	pdbController cache.Controller
 	pdbLister     cache.StoreToPodDisruptionBudgetLister
 
-	podController cache.ControllerInterface
+	podController cache.Controller
 	podLister     cache.StoreToPodLister
 
 	rcIndexer    cache.Indexer
-	rcController *cache.Controller
+	rcController cache.Controller
 	rcLister     cache.StoreToReplicationControllerLister
 
 	rsStore      cache.Store
-	rsController *cache.Controller
+	rsController cache.Controller
 	rsLister     cache.StoreToReplicaSetLister
 
 	dIndexer    cache.Indexer
-	dController *cache.Controller
+	dController cache.Controller
 	dLister     cache.StoreToDeploymentLister
 
 	ssStore      cache.Store
-	ssController *cache.Controller
+	ssController cache.Controller
 	ssLister     cache.StoreToStatefulSetLister
 
 	// PodDisruptionBudget keys that need to be synced.

pkg/controller/endpoint/endpoints_controller.go

@@ -147,8 +147,8 @@ type EndpointController struct {
 
 	// Since we join two objects, we'll watch both of them with
 	// controllers.
-	serviceController *cache.Controller
+	serviceController cache.Controller
-	podController     cache.ControllerInterface
+	podController     cache.Controller
 	// podStoreSynced returns true if the pod store has been synced at least once.
 	// Added as a member to the struct to allow injection for testing.
 	podStoreSynced func() bool

pkg/controller/garbagecollector/garbagecollector.go

@@ -48,7 +48,7 @@ const ResourceResyncTime time.Duration = 0
 
 type monitor struct {
 	store      cache.Store
-	controller *cache.Controller
+	controller cache.Controller
 }
 
 type objectReference struct {

pkg/controller/namespace/namespace_controller.go

@@ -56,7 +56,7 @@ type NamespaceController struct {
 	// store that holds the namespaces
 	store cache.Store
 	// controller that observes the namespaces
-	controller *cache.Controller
+	controller cache.Controller
 	// namespaces that have been queued up for processing by workers
 	queue workqueue.RateLimitingInterface
 	// function to list of preferred resources for namespace deletion

pkg/controller/petset/pet_set.go

@@ -64,12 +64,12 @@ type StatefulSetController struct {
 	// podStoreSynced returns true if the pod store has synced at least once.
 	podStoreSynced func() bool
 	// Watches changes to all pods.
-	podController cache.ControllerInterface
+	podController cache.Controller
 
 	// A store of StatefulSets, populated by the psController.
 	psStore cache.StoreToStatefulSetLister
 	// Watches changes to all StatefulSets.
-	psController *cache.Controller
+	psController cache.Controller
 
 	// A store of the 1 unhealthy pet blocking progress for a given ps
 	blockingPetStore *unhealthyPetTracker

pkg/controller/podautoscaler/horizontal.go

@@ -66,13 +66,13 @@ type HorizontalController struct {
 	// A store of HPA objects, populated by the controller.
 	store cache.Store
 	// Watches changes to all HPA objects.
-	controller *cache.Controller
+	controller cache.Controller
 }
 
 var downscaleForbiddenWindow = 5 * time.Minute
 var upscaleForbiddenWindow = 3 * time.Minute
 
-func newInformer(controller *HorizontalController, resyncPeriod time.Duration) (cache.Store, *cache.Controller) {
+func newInformer(controller *HorizontalController, resyncPeriod time.Duration) (cache.Store, cache.Controller) {
 	return cache.NewInformer(
 		&cache.ListWatch{
 			ListFunc: func(options v1.ListOptions) (runtime.Object, error) {

pkg/controller/podgc/gc_controller.go

@@ -50,7 +50,7 @@ type PodGCController struct {
 	internalPodInformer cache.SharedIndexInformer
 
 	podStore      cache.StoreToPodLister
-	podController cache.ControllerInterface
+	podController cache.Controller
 
 	deletePod              func(namespace, name string) error
 	terminatedPodThreshold int

pkg/controller/podgc/gc_controller_test.go

@@ -37,6 +37,10 @@ func (*FakeController) HasSynced() bool {
 	return true
 }
 
+func (*FakeController) LastSyncResourceVersion() string {
+	return ""
+}
+
 func TestGCTerminated(t *testing.T) {
 	type nameToPhase struct {
 		name  string

pkg/controller/replication/replication_controller.go

@@ -86,7 +86,7 @@ type ReplicationManager struct {
 	// A store of pods, populated by the podController
 	podLister cache.StoreToPodLister
 	// Watches changes to all pods
-	podController cache.ControllerInterface
+	podController cache.Controller
 	// podListerSynced returns true if the pod store has been synced at least once.
 	// Added as a member to the struct to allow injection for testing.
 	podListerSynced func() bool

pkg/controller/resourcequota/replenishment_controller.go

@@ -90,7 +90,7 @@ func ObjectReplenishmentDeleteFunc(options *ReplenishmentControllerOptions) func
 type ReplenishmentControllerFactory interface {
 	// NewController returns a controller configured with the specified options.
 	// This method is NOT thread-safe.
-	NewController(options *ReplenishmentControllerOptions) (cache.ControllerInterface, error)
+	NewController(options *ReplenishmentControllerOptions) (cache.Controller, error)
 }
 
 // replenishmentControllerFactory implements ReplenishmentControllerFactory
@@ -118,7 +118,8 @@ func NewReplenishmentControllerFactoryFromClient(kubeClient clientset.Interface)
 func controllerFor(
 	groupResource schema.GroupResource,
 	f informers.SharedInformerFactory,
-	handlerFuncs cache.ResourceEventHandlerFuncs) (cache.ControllerInterface, error) {
+	handlerFuncs cache.ResourceEventHandlerFuncs,
+) (cache.Controller, error) {
 	genericInformer, err := f.ForResource(groupResource)
 	if err != nil {
 		return nil, err
@@ -128,7 +129,7 @@ func controllerFor(
 	return informer.GetController(), nil
 }
 
-func (r *replenishmentControllerFactory) NewController(options *ReplenishmentControllerOptions) (result cache.ControllerInterface, err error) {
+func (r *replenishmentControllerFactory) NewController(options *ReplenishmentControllerOptions) (result cache.Controller, err error) {
 	if r.kubeClient != nil && r.kubeClient.Core().RESTClient().GetRateLimiter() != nil {
 		metrics.RegisterMetricAndTrackRateLimiterUsage("replenishment_controller", r.kubeClient.Core().RESTClient().GetRateLimiter())
 	}
@@ -276,7 +277,7 @@ func IsUnhandledGroupKindError(err error) bool {
 // returning the first success or failure it hits.  If there are no hits either way, it return an UnhandledGroupKind error
 type UnionReplenishmentControllerFactory []ReplenishmentControllerFactory
 
-func (f UnionReplenishmentControllerFactory) NewController(options *ReplenishmentControllerOptions) (cache.ControllerInterface, error) {
+func (f UnionReplenishmentControllerFactory) NewController(options *ReplenishmentControllerOptions) (cache.Controller, error) {
 	for _, factory := range f {
 		controller, err := factory.NewController(options)
 		if !IsUnhandledGroupKindError(err) {

pkg/controller/resourcequota/resource_quota_controller.go

@@ -60,7 +60,7 @@ type ResourceQuotaController struct {
 	// An index of resource quota objects by namespace
 	rqIndexer cache.Indexer
 	// Watches changes to all resource quota
-	rqController *cache.Controller
+	rqController cache.Controller
 	// ResourceQuota objects that need to be synchronized
 	queue workqueue.RateLimitingInterface
 	// missingUsageQueue holds objects that are missing the initial usage informatino
@@ -72,7 +72,7 @@ type ResourceQuotaController struct {
 	// knows how to calculate usage
 	registry quota.Registry
 	// controllers monitoring to notify for replenishment
-	replenishmentControllers []cache.ControllerInterface
+	replenishmentControllers []cache.Controller
 }
 
 func NewResourceQuotaController(options *ResourceQuotaControllerOptions) *ResourceQuotaController {
@@ -83,7 +83,7 @@ func NewResourceQuotaController(options *ResourceQuotaControllerOptions) *Resour
 		missingUsageQueue:        workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "resourcequota_priority"),
 		resyncPeriod:             options.ResyncPeriod,
 		registry:                 options.Registry,
-		replenishmentControllers: []cache.ControllerInterface{},
+		replenishmentControllers: []cache.Controller{},
 	}
 	if options.KubeClient != nil && options.KubeClient.Core().RESTClient().GetRateLimiter() != nil {
 		metrics.RegisterMetricAndTrackRateLimiterUsage("resource_quota_controller", options.KubeClient.Core().RESTClient().GetRateLimiter())

pkg/controller/route/routecontroller.go

@@ -54,7 +54,7 @@ type RouteController struct {
 	clusterName string
 	clusterCIDR *net.IPNet
 	// Node framework and store
-	nodeController *cache.Controller
+	nodeController cache.Controller
 	nodeStore      cache.StoreToNodeLister
 }
 

pkg/controller/service/servicecontroller.go

@@ -87,7 +87,7 @@ type ServiceController struct {
 	// A store of services, populated by the serviceController
 	serviceStore cache.StoreToServiceLister
 	// Watches changes to all services
-	serviceController *cache.Controller
+	serviceController cache.Controller
 	eventBroadcaster  record.EventBroadcaster
 	eventRecorder     record.EventRecorder
 	nodeLister        cache.StoreToNodeLister

pkg/controller/serviceaccount/tokens_controller.go

@@ -145,8 +145,8 @@ type TokensController struct {
 	secrets         cache.Indexer
 
 	// Since we join two objects, we'll watch both of them with controllers.
-	serviceAccountController *cache.Controller
+	serviceAccountController cache.Controller
-	secretController         *cache.Controller
+	secretController         cache.Controller
 
 	// syncServiceAccountQueue handles service account events:
 	//   * ensures a referenced token exists for service accounts which still exist

pkg/controller/volume/persistentvolume/pv_controller.go

@@ -146,10 +146,10 @@ const createProvisionedPVInterval = 10 * time.Second
 // cache.Controllers that watch PersistentVolume and PersistentVolumeClaim
 // changes.
 type PersistentVolumeController struct {
-	volumeController          *cache.Controller
+	volumeController          cache.Controller
 	volumeInformer            cache.Indexer
 	volumeSource              cache.ListerWatcher
-	claimController           *cache.Controller
+	claimController           cache.Controller
 	claimInformer             cache.Store
 	claimSource               cache.ListerWatcher
 	classReflector            *cache.Reflector

plugin/pkg/scheduler/factory/factory.go

@@ -80,12 +80,12 @@ type ConfigFactory struct {
 	StopEverything chan struct{}
 
 	informerFactory       informers.SharedInformerFactory
-	scheduledPodPopulator cache.ControllerInterface
+	scheduledPodPopulator cache.Controller
-	nodePopulator         cache.ControllerInterface
+	nodePopulator         cache.Controller
-	pvPopulator           cache.ControllerInterface
+	pvPopulator           cache.Controller
-	pvcPopulator          cache.ControllerInterface
+	pvcPopulator          cache.Controller
-	servicePopulator      cache.ControllerInterface
+	servicePopulator      cache.Controller
-	controllerPopulator   cache.ControllerInterface
+	controllerPopulator   cache.Controller
 
 	schedulerCache schedulercache.Cache
 

staging/src/k8s.io/client-go/tools/cache/controller.go

@@ -61,21 +61,20 @@ type Config struct {
 type ProcessFunc func(obj interface{}) error
 
 // Controller is a generic controller framework.
-type Controller struct {
+type controller struct {
 	config         Config
 	reflector      *Reflector
 	reflectorMutex sync.RWMutex
 }
 
-// TODO make the "Controller" private, and convert all references to use ControllerInterface instead
+type Controller interface {
-type ControllerInterface interface {
 	Run(stopCh <-chan struct{})
 	HasSynced() bool
 }
 
 // New makes a new Controller from the given Config.
-func New(c *Config) *Controller {
+func New(c *Config) Controller {
-	ctlr := &Controller{
+	ctlr := &controller{
 		config: *c,
 	}
 	return ctlr
@@ -84,7 +83,7 @@ func New(c *Config) *Controller {
 // Run begins processing items, and will continue until a value is sent down stopCh.
 // It's an error to call Run more than once.
 // Run blocks; call via go.
-func (c *Controller) Run(stopCh <-chan struct{}) {
+func (c *controller) Run(stopCh <-chan struct{}) {
 	defer utilruntime.HandleCrash()
 	r := NewReflector(
 		c.config.ListerWatcher,
@@ -103,18 +102,15 @@ func (c *Controller) Run(stopCh <-chan struct{}) {
 }
 
 // Returns true once this controller has completed an initial resource listing
-func (c *Controller) HasSynced() bool {
+func (c *controller) HasSynced() bool {
 	return c.config.Queue.HasSynced()
 }
 
-// Requeue adds the provided object back into the queue if it does not already exist.
+func (c *controller) LastSyncResourceVersion() string {
-func (c *Controller) Requeue(obj interface{}) error {
+	if c.reflector == nil {
-	return c.config.Queue.AddIfNotPresent(Deltas{
+		return ""
-		Delta{
+	}
-			Type:   Sync,
+	return c.reflector.LastSyncResourceVersion()
-			Object: obj,
-		},
-	})
 }
 
 // processLoop drains the work queue.
@@ -126,7 +122,7 @@ func (c *Controller) Requeue(obj interface{}) error {
 // actually exit when the controller is stopped. Or just give up on this stuff
 // ever being stoppable. Converting this whole package to use Context would
 // also be helpful.
-func (c *Controller) processLoop() {
+func (c *controller) processLoop() {
 	for {
 		obj, err := c.config.Queue.Pop(PopProcessFunc(c.config.Process))
 		if err != nil {
@@ -218,7 +214,7 @@ func NewInformer(
 	objType runtime.Object,
 	resyncPeriod time.Duration,
 	h ResourceEventHandler,
-) (Store, *Controller) {
+) (Store, Controller) {
 	// This will hold the client state, as we know it.
 	clientState := NewStore(DeletionHandlingMetaNamespaceKeyFunc)
 
@@ -284,7 +280,7 @@ func NewIndexerInformer(
 	resyncPeriod time.Duration,
 	h ResourceEventHandler,
 	indexers Indexers,
-) (Indexer, *Controller) {
+) (Indexer, Controller) {
 	// This will hold the client state, as we know it.
 	clientState := NewIndexer(DeletionHandlingMetaNamespaceKeyFunc, indexers)
 

staging/src/k8s.io/client-go/tools/cache/shared_informer.go

@@ -43,7 +43,7 @@ type SharedInformer interface {
 	AddEventHandler(handler ResourceEventHandler) error
 	GetStore() Store
 	// GetController gives back a synthetic interface that "votes" to start the informer
-	GetController() ControllerInterface
+	GetController() Controller
 	Run(stopCh <-chan struct{})
 	HasSynced() bool
 	LastSyncResourceVersion() string
@@ -108,7 +108,7 @@ func WaitForCacheSync(stopCh <-chan struct{}, cacheSyncs ...InformerSynced) bool
 
 type sharedIndexInformer struct {
 	indexer    Indexer
-	controller *Controller
+	controller Controller
 
 	processor             *sharedProcessor
 	cacheMutationDetector CacheMutationDetector
@@ -145,6 +145,10 @@ func (v *dummyController) HasSynced() bool {
 	return v.informer.HasSynced()
 }
 
+func (c *dummyController) LastSyncResourceVersion() string {
+	return ""
+}
+
 type updateNotification struct {
 	oldObj interface{}
 	newObj interface{}
@@ -232,7 +236,7 @@ func (s *sharedIndexInformer) AddIndexers(indexers Indexers) error {
 	return s.indexer.AddIndexers(indexers)
 }
 
-func (s *sharedIndexInformer) GetController() ControllerInterface {
+func (s *sharedIndexInformer) GetController() Controller {
 	return &dummyController{informer: s}
 }
 

test/e2e/daemon_restart.go

@@ -192,7 +192,7 @@ var _ = framework.KubeDescribe("DaemonRestart [Disruptive]", func() {
 	existingPods := cache.NewStore(cache.MetaNamespaceKeyFunc)
 	var ns string
 	var config testutils.RCConfig
-	var controller *cache.Controller
+	var controller cache.Controller
 	var newPods cache.Store
 	var stopCh chan struct{}
 	var tracker *podTracker

test/e2e/network_partition.go

@@ -188,7 +188,7 @@ var _ = framework.KubeDescribe("Network Partition [Disruptive] [Slow]", func() {
 				nodeSelector := fields.OneTermEqualSelector("metadata.name", node.Name)
 				stopCh := make(chan struct{})
 				newNode := make(chan *v1.Node)
-				var controller *cache.Controller
+				var controller cache.Controller
 				_, controller = cache.NewInformer(
 					&cache.ListWatch{
 						ListFunc: func(options v1.ListOptions) (runtime.Object, error) {

test/e2e_node/density_test.go

@@ -476,8 +476,7 @@ func verifyPodStartupLatency(expect, actual framework.LatencyMetric) error {
 }
 
 // newInformerWatchPod creates an informer to check whether all pods are running.
-func newInformerWatchPod(f *framework.Framework, mutex *sync.Mutex, watchTimes map[string]metav1.Time,
+func newInformerWatchPod(f *framework.Framework, mutex *sync.Mutex, watchTimes map[string]metav1.Time, podType string) cache.Controller {
-	podType string) *cache.Controller {
 	ns := f.Namespace.Name
 	checkPodRunning := func(p *v1.Pod) {
 		mutex.Lock()