Add resourceVersion=0 paginated list integration test for disabled and enabled watch cache

staging/src/k8s.io/apiserver/pkg/storage/cacher/cacher.go

@@ -247,6 +247,8 @@ func NewCacherFromConfig(config Config) *Cacher {
 
 	stopCh := make(chan struct{})
 	reflector := cache.NewNamedReflector(reflectorName, listerWatcher, obj, watchCache, 0)
+	// Configure reflector's pager to for an appropriate pagination chunk size for fetching data from
+	// storage. The pager falls back to full list if paginated list calls fail due to an "Expired" error.
 	reflector.WatchListPageSize = storageWatchListPageSize
 	cacher := &Cacher{
 		ready:       newReady(),

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

@@ -192,6 +192,7 @@ func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
 			if r.WatchListPageSize != 0 {
 				pager.PageSize = r.WatchListPageSize
 			}
+			// Pager falls back to full list if paginated list calls fail due to an "Expired" error.
 			list, err = pager.List(context.Background(), options)
 			close(listCh)
 		}()

test/integration/apiserver/apiserver_test.go

@@ -65,8 +65,16 @@ func setup(t *testing.T, groupVersions ...schema.GroupVersion) (*httptest.Server
 	return setupWithResources(t, groupVersions, nil)
 }
 
+func setupWithOptions(t *testing.T, opts *framework.MasterConfigOptions, groupVersions ...schema.GroupVersion) (*httptest.Server, clientset.Interface, framework.CloseFunc) {
+	return setupWithResourcesWithOptions(t, opts, groupVersions, nil)
+}
+
 func setupWithResources(t *testing.T, groupVersions []schema.GroupVersion, resources []schema.GroupVersionResource) (*httptest.Server, clientset.Interface, framework.CloseFunc) {
-	masterConfig := framework.NewIntegrationTestMasterConfig()
+	return setupWithResourcesWithOptions(t, &framework.MasterConfigOptions{}, groupVersions, resources)
+}
+
+func setupWithResourcesWithOptions(t *testing.T, opts *framework.MasterConfigOptions, groupVersions []schema.GroupVersion, resources []schema.GroupVersionResource) (*httptest.Server, clientset.Interface, framework.CloseFunc) {
+	masterConfig := framework.NewIntegrationTestMasterConfigWithOptions(opts)
 	if len(groupVersions) > 0 || len(resources) > 0 {
 		resourceConfig := master.DefaultAPIResourceConfigSource()
 		resourceConfig.EnableVersions(groupVersions...)
@@ -189,6 +197,62 @@ func Test202StatusCode(t *testing.T) {
 	verifyStatusCode(t, "DELETE", s.URL+path.Join("/apis/apps/v1/namespaces", ns.Name, "replicasets", rs.Name), cascDel, 202)
 }
 
+func TestListResourceVersion0(t *testing.T) {
+	var testcases = []struct {
+		name              string
+		watchCacheEnabled bool
+	}{
+		{
+			name:              "watchCacheOn",
+			watchCacheEnabled: true,
+		},
+		{
+			name:              "watchCacheOff",
+			watchCacheEnabled: false,
+		},
+	}
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.APIListChunking, true)()
+			etcdOptions := framework.DefaultEtcdOptions()
+			etcdOptions.EnableWatchCache = tc.watchCacheEnabled
+			s, clientSet, closeFn := setupWithOptions(t, &framework.MasterConfigOptions{EtcdOptions: etcdOptions})
+			defer closeFn()
+
+			ns := framework.CreateTestingNamespace("list-paging", s, t)
+			defer framework.DeleteTestingNamespace(ns, s, t)
+
+			rsClient := clientSet.AppsV1().ReplicaSets(ns.Name)
+
+			for i := 0; i < 10; i++ {
+				rs := newRS(ns.Name)
+				rs.Name = fmt.Sprintf("test-%d", i)
+				if _, err := rsClient.Create(rs); err != nil {
+					t.Fatal(err)
+				}
+			}
+
+			pagerFn := func(opts metav1.ListOptions) (runtime.Object, error) {
+				return rsClient.List(opts)
+			}
+
+			p := pager.New(pager.SimplePageFunc(pagerFn))
+			p.PageSize = 3
+			listObj, err := p.List(context.Background(), metav1.ListOptions{ResourceVersion: "0"})
+			if err != nil {
+				t.Fatalf("Unexpected list error: %v", err)
+			}
+			items, err := meta.ExtractList(listObj)
+			if err != nil {
+				t.Fatalf("Failed to extract list from %v", listObj)
+			}
+			if len(items) != 10 {
+				t.Errorf("Expected list size of 10 but got %d", len(items))
+			}
+		})
+	}
+}
+
 func TestAPIListChunking(t *testing.T) {
 	defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.APIListChunking, true)()
 	s, clientSet, closeFn := setup(t)

test/integration/framework/master_utils.go

@@ -242,7 +242,13 @@ func startMasterOrDie(masterConfig *master.Config, incomingServer *httptest.Serv
 
 // NewIntegrationTestMasterConfig returns the master config appropriate for most integration tests.
 func NewIntegrationTestMasterConfig() *master.Config {
-	masterConfig := NewMasterConfig()
+	return NewIntegrationTestMasterConfigWithOptions(&MasterConfigOptions{})
+}
+
+// NewIntegrationTestMasterConfigWithOptions returns the master config appropriate for most integration tests
+// configured with the provided options.
+func NewIntegrationTestMasterConfigWithOptions(opts *MasterConfigOptions) *master.Config {
+	masterConfig := NewMasterConfigWithOptions(opts)
 	masterConfig.GenericConfig.PublicAddress = net.ParseIP("192.168.10.4")
 	masterConfig.ExtraConfig.APIResourceConfigSource = master.DefaultAPIResourceConfigSource()
 
@@ -252,13 +258,32 @@ func NewIntegrationTestMasterConfig() *master.Config {
 	return masterConfig
 }
 
-// NewMasterConfig returns a basic master config.
+// MasterConfigOptions are the configurable options for a new integration test master config.
-func NewMasterConfig() *master.Config {
+type MasterConfigOptions struct {
+	EtcdOptions *options.EtcdOptions
+}
+
+// DefaultEtcdOptions are the default EtcdOptions for use with integration tests.
+func DefaultEtcdOptions() *options.EtcdOptions {
 	// This causes the integration tests to exercise the etcd
 	// prefix code, so please don't change without ensuring
 	// sufficient coverage in other ways.
 	etcdOptions := options.NewEtcdOptions(storagebackend.NewDefaultConfig(uuid.New(), nil))
 	etcdOptions.StorageConfig.Transport.ServerList = []string{GetEtcdURL()}
+	return etcdOptions
+}
+
+// NewMasterConfig returns a basic master config.
+func NewMasterConfig() *master.Config {
+	return NewMasterConfigWithOptions(&MasterConfigOptions{})
+}
+
+// NewMasterConfigWithOptions returns a basic master config configured with the provided options.
+func NewMasterConfigWithOptions(opts *MasterConfigOptions) *master.Config {
+	etcdOptions := DefaultEtcdOptions()
+	if opts.EtcdOptions != nil {
+		etcdOptions = opts.EtcdOptions
+	}
 
 	info, _ := runtime.SerializerInfoForMediaType(legacyscheme.Codecs.SupportedMediaTypes(), runtime.ContentTypeJSON)
 	ns := NewSingleContentTypeSerializer(legacyscheme.Scheme, info)