xds/internal/client/client_watchers_listener_test.go - third_party/github.com/grpc/grpc-go - Git at Google

 /*
  *
  * Copyright 2020 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  */

 package client

 import (
 	"context"
 	"testing"

 	"google.golang.org/grpc/internal/testutils"
 )

 type ldsUpdateErr struct {
 	u   ListenerUpdate
 	err error
 }

 // TestLDSWatch covers the cases:
 // - an update is received after a watch()
 // - an update for another resource name
 // - an update is received after cancel()
 func (s) TestLDSWatch(t *testing.T) {
 	apiClientCh, cleanup := overrideNewAPIClient()
 	defer cleanup()

 	client, err := newWithConfig(clientOpts(testXDSServer, false))
 	if err != nil {
 		t.Fatalf("failed to create client: %v", err)
 	}
 	defer client.Close()

 	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
 	defer cancel()
 	c, err := apiClientCh.Receive(ctx)
 	if err != nil {
 		t.Fatalf("timeout when waiting for API client to be created: %v", err)
 	}
 	apiClient := c.(*testAPIClient)

 	ldsUpdateCh := testutils.NewChannel()
 	cancelWatch := client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
 		ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
 	})
 	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 		t.Fatalf("want new watch to start, got error %v", err)
 	}

 	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
 	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
 		t.Fatal(err)
 	}

 	// Another update, with an extra resource for a different resource name.
 	client.NewListeners(map[string]ListenerUpdate{
 		testLDSName:  wantUpdate,
 		"randomName": {},
 	})
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
 		t.Fatal(err)
 	}

 	// Cancel watch, and send update again.
 	cancelWatch()
 	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
 	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
 	defer sCancel()
 	if u, err := ldsUpdateCh.Receive(sCtx); err != context.DeadlineExceeded {
 		t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
 	}
 }

 // TestLDSTwoWatchSameResourceName covers the case where an update is received
 // after two watch() for the same resource name.
 func (s) TestLDSTwoWatchSameResourceName(t *testing.T) {
 	apiClientCh, cleanup := overrideNewAPIClient()
 	defer cleanup()

 	client, err := newWithConfig(clientOpts(testXDSServer, false))
 	if err != nil {
 		t.Fatalf("failed to create client: %v", err)
 	}
 	defer client.Close()

 	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
 	defer cancel()
 	c, err := apiClientCh.Receive(ctx)
 	if err != nil {
 		t.Fatalf("timeout when waiting for API client to be created: %v", err)
 	}
 	apiClient := c.(*testAPIClient)

 	const count = 2
 	var (
 		ldsUpdateChs    []*testutils.Channel
 		cancelLastWatch func()
 	)

 	for i := 0; i < count; i++ {
 		ldsUpdateCh := testutils.NewChannel()
 		ldsUpdateChs = append(ldsUpdateChs, ldsUpdateCh)
 		cancelLastWatch = client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
 			ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
 		})

 		if i == 0 {
 			// A new watch is registered on the underlying API client only for
 			// the first iteration because we are using the same resource name.
 			if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 				t.Fatalf("want new watch to start, got error %v", err)
 			}
 		}
 	}

 	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
 	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
 	for i := 0; i < count; i++ {
 		if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate); err != nil {
 			t.Fatal(err)
 		}
 	}

 	// Cancel the last watch, and send update again.
 	cancelLastWatch()
 	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
 	for i := 0; i < count-1; i++ {
 		if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate); err != nil {
 			t.Fatal(err)
 		}
 	}

 	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
 	defer sCancel()
 	if u, err := ldsUpdateChs[count-1].Receive(sCtx); err != context.DeadlineExceeded {
 		t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
 	}
 }

 // TestLDSThreeWatchDifferentResourceName covers the case where an update is
 // received after three watch() for different resource names.
 func (s) TestLDSThreeWatchDifferentResourceName(t *testing.T) {
 	apiClientCh, cleanup := overrideNewAPIClient()
 	defer cleanup()

 	client, err := newWithConfig(clientOpts(testXDSServer, false))
 	if err != nil {
 		t.Fatalf("failed to create client: %v", err)
 	}
 	defer client.Close()

 	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
 	defer cancel()
 	c, err := apiClientCh.Receive(ctx)
 	if err != nil {
 		t.Fatalf("timeout when waiting for API client to be created: %v", err)
 	}
 	apiClient := c.(*testAPIClient)

 	var ldsUpdateChs []*testutils.Channel
 	const count = 2

 	// Two watches for the same name.
 	for i := 0; i < count; i++ {
 		ldsUpdateCh := testutils.NewChannel()
 		ldsUpdateChs = append(ldsUpdateChs, ldsUpdateCh)
 		client.WatchListener(testLDSName+"1", func(update ListenerUpdate, err error) {
 			ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
 		})

 		if i == 0 {
 			// A new watch is registered on the underlying API client only for
 			// the first iteration because we are using the same resource name.
 			if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 				t.Fatalf("want new watch to start, got error %v", err)
 			}
 		}
 	}

 	// Third watch for a different name.
 	ldsUpdateCh2 := testutils.NewChannel()
 	client.WatchListener(testLDSName+"2", func(update ListenerUpdate, err error) {
 		ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
 	})
 	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 		t.Fatalf("want new watch to start, got error %v", err)
 	}

 	wantUpdate1 := ListenerUpdate{RouteConfigName: testRDSName + "1"}
 	wantUpdate2 := ListenerUpdate{RouteConfigName: testRDSName + "2"}
 	client.NewListeners(map[string]ListenerUpdate{
 		testLDSName + "1": wantUpdate1,
 		testLDSName + "2": wantUpdate2,
 	})

 	for i := 0; i < count; i++ {
 		if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate1); err != nil {
 			t.Fatal(err)
 		}
 	}
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
 		t.Fatal(err)
 	}
 }

 // TestLDSWatchAfterCache covers the case where watch is called after the update
 // is in cache.
 func (s) TestLDSWatchAfterCache(t *testing.T) {
 	apiClientCh, cleanup := overrideNewAPIClient()
 	defer cleanup()

 	client, err := newWithConfig(clientOpts(testXDSServer, false))
 	if err != nil {
 		t.Fatalf("failed to create client: %v", err)
 	}
 	defer client.Close()

 	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
 	defer cancel()
 	c, err := apiClientCh.Receive(ctx)
 	if err != nil {
 		t.Fatalf("timeout when waiting for API client to be created: %v", err)
 	}
 	apiClient := c.(*testAPIClient)

 	ldsUpdateCh := testutils.NewChannel()
 	client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
 		ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
 	})
 	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 		t.Fatalf("want new watch to start, got error %v", err)
 	}

 	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
 	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
 		t.Fatal(err)
 	}

 	// Another watch for the resource in cache.
 	ldsUpdateCh2 := testutils.NewChannel()
 	client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
 		ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
 	})
 	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
 	defer sCancel()
 	if n, err := apiClient.addWatches[ListenerResource].Receive(sCtx); err != context.DeadlineExceeded {
 		t.Fatalf("want no new watch to start (recv timeout), got resource name: %v error %v", n, err)
 	}

 	// New watch should receive the update.
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate); err != nil {
 		t.Fatal(err)
 	}

 	// Old watch should see nothing.
 	sCtx, sCancel = context.WithTimeout(ctx, defaultTestShortTimeout)
 	defer sCancel()
 	if u, err := ldsUpdateCh.Receive(sCtx); err != context.DeadlineExceeded {
 		t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
 	}
 }

 // TestLDSResourceRemoved covers the cases:
 // - an update is received after a watch()
 // - another update is received, with one resource removed
 //   - this should trigger callback with resource removed error
 // - one more update without the removed resource
 //   - the callback (above) shouldn't receive any update
 func (s) TestLDSResourceRemoved(t *testing.T) {
 	apiClientCh, cleanup := overrideNewAPIClient()
 	defer cleanup()

 	client, err := newWithConfig(clientOpts(testXDSServer, false))
 	if err != nil {
 		t.Fatalf("failed to create client: %v", err)
 	}
 	defer client.Close()

 	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
 	defer cancel()
 	c, err := apiClientCh.Receive(ctx)
 	if err != nil {
 		t.Fatalf("timeout when waiting for API client to be created: %v", err)
 	}
 	apiClient := c.(*testAPIClient)

 	ldsUpdateCh1 := testutils.NewChannel()
 	client.WatchListener(testLDSName+"1", func(update ListenerUpdate, err error) {
 		ldsUpdateCh1.Send(ldsUpdateErr{u: update, err: err})
 	})
 	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 		t.Fatalf("want new watch to start, got error %v", err)
 	}
 	// Another watch for a different name.
 	ldsUpdateCh2 := testutils.NewChannel()
 	client.WatchListener(testLDSName+"2", func(update ListenerUpdate, err error) {
 		ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
 	})
 	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
 		t.Fatalf("want new watch to start, got error %v", err)
 	}

 	wantUpdate1 := ListenerUpdate{RouteConfigName: testEDSName + "1"}
 	wantUpdate2 := ListenerUpdate{RouteConfigName: testEDSName + "2"}
 	client.NewListeners(map[string]ListenerUpdate{
 		testLDSName + "1": wantUpdate1,
 		testLDSName + "2": wantUpdate2,
 	})
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh1, wantUpdate1); err != nil {
 		t.Fatal(err)
 	}
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
 		t.Fatal(err)
 	}

 	// Send another update to remove resource 1.
 	client.NewListeners(map[string]ListenerUpdate{testLDSName + "2": wantUpdate2})

 	// Watcher 1 should get an error.
 	if u, err := ldsUpdateCh1.Receive(ctx); err != nil || ErrType(u.(ldsUpdateErr).err) != ErrorTypeResourceNotFound {
 		t.Errorf("unexpected ListenerUpdate: %v, error receiving from channel: %v, want update with error resource not found", u, err)
 	}

 	// Watcher 2 should get the same update again.
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
 		t.Fatal(err)
 	}

 	// Send one more update without resource 1.
 	client.NewListeners(map[string]ListenerUpdate{testLDSName + "2": wantUpdate2})

 	// Watcher 1 should not see an update.
 	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
 	defer sCancel()
 	if u, err := ldsUpdateCh1.Receive(sCtx); err != context.DeadlineExceeded {
 		t.Errorf("unexpected ListenerUpdate: %v, want receiving from channel timeout", u)
 	}

 	// Watcher 2 should get the same update again.
 	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
 		t.Fatal(err)
 	}
 }
	/*
	*
	* Copyright 2020 gRPC authors.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	*/

	package client

	import (
	"context"
	"testing"

	"google.golang.org/grpc/internal/testutils"
	)

	type ldsUpdateErr struct {
	u ListenerUpdate
	err error
	}

	// TestLDSWatch covers the cases:
	// - an update is received after a watch()
	// - an update for another resource name
	// - an update is received after cancel()
	func (s) TestLDSWatch(t *testing.T) {
	apiClientCh, cleanup := overrideNewAPIClient()
	defer cleanup()

	client, err := newWithConfig(clientOpts(testXDSServer, false))
	if err != nil {
	t.Fatalf("failed to create client: %v", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	c, err := apiClientCh.Receive(ctx)
	if err != nil {
	t.Fatalf("timeout when waiting for API client to be created: %v", err)
	}
	apiClient := c.(*testAPIClient)

	ldsUpdateCh := testutils.NewChannel()
	cancelWatch := client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
	ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
	})
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}

	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
	t.Fatal(err)
	}

	// Another update, with an extra resource for a different resource name.
	client.NewListeners(map[string]ListenerUpdate{
	testLDSName: wantUpdate,
	"randomName": {},
	})
	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
	t.Fatal(err)
	}

	// Cancel watch, and send update again.
	cancelWatch()
	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
	defer sCancel()
	if u, err := ldsUpdateCh.Receive(sCtx); err != context.DeadlineExceeded {
	t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
	}
	}

	// TestLDSTwoWatchSameResourceName covers the case where an update is received
	// after two watch() for the same resource name.
	func (s) TestLDSTwoWatchSameResourceName(t *testing.T) {
	apiClientCh, cleanup := overrideNewAPIClient()
	defer cleanup()

	client, err := newWithConfig(clientOpts(testXDSServer, false))
	if err != nil {
	t.Fatalf("failed to create client: %v", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	c, err := apiClientCh.Receive(ctx)
	if err != nil {
	t.Fatalf("timeout when waiting for API client to be created: %v", err)
	}
	apiClient := c.(*testAPIClient)

	const count = 2
	var (
	ldsUpdateChs []*testutils.Channel
	cancelLastWatch func()
	)

	for i := 0; i < count; i++ {
	ldsUpdateCh := testutils.NewChannel()
	ldsUpdateChs = append(ldsUpdateChs, ldsUpdateCh)
	cancelLastWatch = client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
	ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
	})

	if i == 0 {
	// A new watch is registered on the underlying API client only for
	// the first iteration because we are using the same resource name.
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}
	}
	}

	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
	for i := 0; i < count; i++ {
	if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate); err != nil {
	t.Fatal(err)
	}
	}

	// Cancel the last watch, and send update again.
	cancelLastWatch()
	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
	for i := 0; i < count-1; i++ {
	if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate); err != nil {
	t.Fatal(err)
	}
	}

	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
	defer sCancel()
	if u, err := ldsUpdateChs[count-1].Receive(sCtx); err != context.DeadlineExceeded {
	t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
	}
	}

	// TestLDSThreeWatchDifferentResourceName covers the case where an update is
	// received after three watch() for different resource names.
	func (s) TestLDSThreeWatchDifferentResourceName(t *testing.T) {
	apiClientCh, cleanup := overrideNewAPIClient()
	defer cleanup()

	client, err := newWithConfig(clientOpts(testXDSServer, false))
	if err != nil {
	t.Fatalf("failed to create client: %v", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	c, err := apiClientCh.Receive(ctx)
	if err != nil {
	t.Fatalf("timeout when waiting for API client to be created: %v", err)
	}
	apiClient := c.(*testAPIClient)

	var ldsUpdateChs []*testutils.Channel
	const count = 2

	// Two watches for the same name.
	for i := 0; i < count; i++ {
	ldsUpdateCh := testutils.NewChannel()
	ldsUpdateChs = append(ldsUpdateChs, ldsUpdateCh)
	client.WatchListener(testLDSName+"1", func(update ListenerUpdate, err error) {
	ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
	})

	if i == 0 {
	// A new watch is registered on the underlying API client only for
	// the first iteration because we are using the same resource name.
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}
	}
	}

	// Third watch for a different name.
	ldsUpdateCh2 := testutils.NewChannel()
	client.WatchListener(testLDSName+"2", func(update ListenerUpdate, err error) {
	ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
	})
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}

	wantUpdate1 := ListenerUpdate{RouteConfigName: testRDSName + "1"}
	wantUpdate2 := ListenerUpdate{RouteConfigName: testRDSName + "2"}
	client.NewListeners(map[string]ListenerUpdate{
	testLDSName + "1": wantUpdate1,
	testLDSName + "2": wantUpdate2,
	})

	for i := 0; i < count; i++ {
	if err := verifyListenerUpdate(ctx, ldsUpdateChs[i], wantUpdate1); err != nil {
	t.Fatal(err)
	}
	}
	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
	t.Fatal(err)
	}
	}

	// TestLDSWatchAfterCache covers the case where watch is called after the update
	// is in cache.
	func (s) TestLDSWatchAfterCache(t *testing.T) {
	apiClientCh, cleanup := overrideNewAPIClient()
	defer cleanup()

	client, err := newWithConfig(clientOpts(testXDSServer, false))
	if err != nil {
	t.Fatalf("failed to create client: %v", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	c, err := apiClientCh.Receive(ctx)
	if err != nil {
	t.Fatalf("timeout when waiting for API client to be created: %v", err)
	}
	apiClient := c.(*testAPIClient)

	ldsUpdateCh := testutils.NewChannel()
	client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
	ldsUpdateCh.Send(ldsUpdateErr{u: update, err: err})
	})
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}

	wantUpdate := ListenerUpdate{RouteConfigName: testRDSName}
	client.NewListeners(map[string]ListenerUpdate{testLDSName: wantUpdate})
	if err := verifyListenerUpdate(ctx, ldsUpdateCh, wantUpdate); err != nil {
	t.Fatal(err)
	}

	// Another watch for the resource in cache.
	ldsUpdateCh2 := testutils.NewChannel()
	client.WatchListener(testLDSName, func(update ListenerUpdate, err error) {
	ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
	})
	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
	defer sCancel()
	if n, err := apiClient.addWatches[ListenerResource].Receive(sCtx); err != context.DeadlineExceeded {
	t.Fatalf("want no new watch to start (recv timeout), got resource name: %v error %v", n, err)
	}

	// New watch should receive the update.
	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate); err != nil {
	t.Fatal(err)
	}

	// Old watch should see nothing.
	sCtx, sCancel = context.WithTimeout(ctx, defaultTestShortTimeout)
	defer sCancel()
	if u, err := ldsUpdateCh.Receive(sCtx); err != context.DeadlineExceeded {
	t.Errorf("unexpected ListenerUpdate: %v, %v, want channel recv timeout", u, err)
	}
	}

	// TestLDSResourceRemoved covers the cases:
	// - an update is received after a watch()
	// - another update is received, with one resource removed
	// - this should trigger callback with resource removed error
	// - one more update without the removed resource
	// - the callback (above) shouldn't receive any update
	func (s) TestLDSResourceRemoved(t *testing.T) {
	apiClientCh, cleanup := overrideNewAPIClient()
	defer cleanup()

	client, err := newWithConfig(clientOpts(testXDSServer, false))
	if err != nil {
	t.Fatalf("failed to create client: %v", err)
	}
	defer client.Close()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	c, err := apiClientCh.Receive(ctx)
	if err != nil {
	t.Fatalf("timeout when waiting for API client to be created: %v", err)
	}
	apiClient := c.(*testAPIClient)

	ldsUpdateCh1 := testutils.NewChannel()
	client.WatchListener(testLDSName+"1", func(update ListenerUpdate, err error) {
	ldsUpdateCh1.Send(ldsUpdateErr{u: update, err: err})
	})
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}
	// Another watch for a different name.
	ldsUpdateCh2 := testutils.NewChannel()
	client.WatchListener(testLDSName+"2", func(update ListenerUpdate, err error) {
	ldsUpdateCh2.Send(ldsUpdateErr{u: update, err: err})
	})
	if _, err := apiClient.addWatches[ListenerResource].Receive(ctx); err != nil {
	t.Fatalf("want new watch to start, got error %v", err)
	}

	wantUpdate1 := ListenerUpdate{RouteConfigName: testEDSName + "1"}
	wantUpdate2 := ListenerUpdate{RouteConfigName: testEDSName + "2"}
	client.NewListeners(map[string]ListenerUpdate{
	testLDSName + "1": wantUpdate1,
	testLDSName + "2": wantUpdate2,
	})
	if err := verifyListenerUpdate(ctx, ldsUpdateCh1, wantUpdate1); err != nil {
	t.Fatal(err)
	}
	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
	t.Fatal(err)
	}

	// Send another update to remove resource 1.
	client.NewListeners(map[string]ListenerUpdate{testLDSName + "2": wantUpdate2})

	// Watcher 1 should get an error.
	if u, err := ldsUpdateCh1.Receive(ctx); err != nil \|\| ErrType(u.(ldsUpdateErr).err) != ErrorTypeResourceNotFound {
	t.Errorf("unexpected ListenerUpdate: %v, error receiving from channel: %v, want update with error resource not found", u, err)
	}

	// Watcher 2 should get the same update again.
	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
	t.Fatal(err)
	}

	// Send one more update without resource 1.
	client.NewListeners(map[string]ListenerUpdate{testLDSName + "2": wantUpdate2})

	// Watcher 1 should not see an update.
	sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
	defer sCancel()
	if u, err := ldsUpdateCh1.Receive(sCtx); err != context.DeadlineExceeded {
	t.Errorf("unexpected ListenerUpdate: %v, want receiving from channel timeout", u)
	}

	// Watcher 2 should get the same update again.
	if err := verifyListenerUpdate(ctx, ldsUpdateCh2, wantUpdate2); err != nil {
	t.Fatal(err)
	}
	}