Copy grpc xDS client from grpc-go

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/traffic/xds/client_test.go

@@ -0,0 +1,292 @@
+/*
+ *
+ * Copyright 2019 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 xds
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/coredns/coredns/plugin/traffic/xds/bootstrap"
+
+	corepb "github.com/envoyproxy/go-control-plane/envoy/api/v2/core"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/xds/internal/testutils"
+	"google.golang.org/grpc/xds/internal/testutils/fakeserver"
+)
+
+func clientOpts(balancerName string) Options {
+	return Options{
+		Config: bootstrap.Config{
+			BalancerName: balancerName,
+			Creds:        grpc.WithInsecure(),
+			NodeProto:    &corepb.Node{},
+		},
+		// WithTimeout is deprecated. But we are OK to call it here from the
+		// test, so we clearly know that the dial failed.
+		DialOpts: []grpc.DialOption{grpc.WithTimeout(5 * time.Second), grpc.WithBlock()},
+	}
+}
+
+func TestNew(t *testing.T) {
+	fakeServer, cleanup, err := fakeserver.StartServer()
+	if err != nil {
+		t.Fatalf("Failed to start fake xDS server: %v", err)
+	}
+	defer cleanup()
+
+	tests := []struct {
+		name    string
+		opts    Options
+		wantErr bool
+	}{
+		{name: "empty-opts", opts: Options{}, wantErr: true},
+		{
+			name: "empty-balancer-name",
+			opts: Options{
+				Config: bootstrap.Config{
+					Creds:     grpc.WithInsecure(),
+					NodeProto: &corepb.Node{},
+				},
+			},
+			wantErr: true,
+		},
+		{
+			name: "empty-dial-creds",
+			opts: Options{
+				Config: bootstrap.Config{
+					BalancerName: "dummy",
+					NodeProto:    &corepb.Node{},
+				},
+			},
+			wantErr: true,
+		},
+		{
+			name: "empty-node-proto",
+			opts: Options{
+				Config: bootstrap.Config{
+					BalancerName: "dummy",
+					Creds:        grpc.WithInsecure(),
+				},
+			},
+			wantErr: true,
+		},
+		{
+			name:    "happy-case",
+			opts:    clientOpts(fakeServer.Address),
+			wantErr: false,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			c, err := New(test.opts)
+			if err == nil {
+				defer c.Close()
+			}
+			if (err != nil) != test.wantErr {
+				t.Fatalf("New(%+v) = %v, wantErr: %v", test.opts, err, test.wantErr)
+			}
+		})
+	}
+}
+
+// TestWatchService tests the happy case of registering a watcher for
+// service updates and receiving a good update.
+func TestWatchService(t *testing.T) {
+	fakeServer, cleanup, err := fakeserver.StartServer()
+	if err != nil {
+		t.Fatalf("Failed to start fake xDS server: %v", err)
+	}
+	defer cleanup()
+
+	xdsClient, err := New(clientOpts(fakeServer.Address))
+	if err != nil {
+		t.Fatalf("New returned error: %v", err)
+	}
+	defer xdsClient.Close()
+	t.Log("Created an xdsClient...")
+
+	callbackCh := testutils.NewChannel()
+	cancelWatch := xdsClient.WatchService(goodLDSTarget1, func(su ServiceUpdate, err error) {
+		if err != nil {
+			callbackCh.Send(fmt.Errorf("xdsClient.WatchService returned error: %v", err))
+			return
+		}
+		if su.Cluster != goodClusterName1 {
+			callbackCh.Send(fmt.Errorf("got clusterName: %+v, want clusterName: %+v", su.Cluster, goodClusterName1))
+			return
+		}
+		callbackCh.Send(nil)
+	})
+	defer cancelWatch()
+	t.Log("Registered a watcher for service updates...")
+
+	// Make the fakeServer send LDS response.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an LDS request")
+	}
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: goodLDSResponse1}
+
+	// Make the fakeServer send RDS response.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an RDS request")
+	}
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: goodRDSResponse1}
+	waitForNilErr(t, callbackCh)
+}
+
+// TestWatchServiceWithNoResponseFromServer tests the case where the
+// xDS server does not respond to the requests being sent out as part of
+// registering a service update watcher. The underlying v2Client will timeout
+// and will send us an error.
+func TestWatchServiceWithNoResponseFromServer(t *testing.T) {
+	fakeServer, cleanup, err := fakeserver.StartServer()
+	if err != nil {
+		t.Fatalf("Failed to start fake xDS server: %v", err)
+	}
+	defer cleanup()
+
+	xdsClient, err := New(clientOpts(fakeServer.Address))
+	if err != nil {
+		t.Fatalf("New returned error: %v", err)
+	}
+	defer xdsClient.Close()
+	t.Log("Created an xdsClient...")
+
+	oldWatchExpiryTimeout := defaultWatchExpiryTimeout
+	defaultWatchExpiryTimeout = 500 * time.Millisecond
+	defer func() {
+		defaultWatchExpiryTimeout = oldWatchExpiryTimeout
+	}()
+
+	callbackCh := testutils.NewChannel()
+	cancelWatch := xdsClient.WatchService(goodLDSTarget1, func(su ServiceUpdate, err error) {
+		if su.Cluster != "" {
+			callbackCh.Send(fmt.Errorf("got clusterName: %+v, want empty clusterName", su.Cluster))
+			return
+		}
+		if err == nil {
+			callbackCh.Send(errors.New("xdsClient.WatchService returned error non-nil error"))
+			return
+		}
+		callbackCh.Send(nil)
+	})
+	defer cancelWatch()
+	t.Log("Registered a watcher for service updates...")
+
+	// Wait for one request from the client, but send no reponses.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an LDS request")
+	}
+	waitForNilErr(t, callbackCh)
+}
+
+// TestWatchServiceEmptyRDS tests the case where the underlying
+// v2Client receives an empty RDS response.
+func TestWatchServiceEmptyRDS(t *testing.T) {
+	fakeServer, cleanup, err := fakeserver.StartServer()
+	if err != nil {
+		t.Fatalf("Failed to start fake xDS server: %v", err)
+	}
+	defer cleanup()
+
+	xdsClient, err := New(clientOpts(fakeServer.Address))
+	if err != nil {
+		t.Fatalf("New returned error: %v", err)
+	}
+	defer xdsClient.Close()
+	t.Log("Created an xdsClient...")
+
+	oldWatchExpiryTimeout := defaultWatchExpiryTimeout
+	defaultWatchExpiryTimeout = 500 * time.Millisecond
+	defer func() {
+		defaultWatchExpiryTimeout = oldWatchExpiryTimeout
+	}()
+
+	callbackCh := testutils.NewChannel()
+	cancelWatch := xdsClient.WatchService(goodLDSTarget1, func(su ServiceUpdate, err error) {
+		if su.Cluster != "" {
+			callbackCh.Send(fmt.Errorf("got clusterName: %+v, want empty clusterName", su.Cluster))
+			return
+		}
+		if err == nil {
+			callbackCh.Send(errors.New("xdsClient.WatchService returned error non-nil error"))
+			return
+		}
+		callbackCh.Send(nil)
+	})
+	defer cancelWatch()
+	t.Log("Registered a watcher for service updates...")
+
+	// Make the fakeServer send LDS response.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an LDS request")
+	}
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: goodLDSResponse1}
+
+	// Make the fakeServer send an empty RDS response.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an RDS request")
+	}
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: noVirtualHostsInRDSResponse}
+	waitForNilErr(t, callbackCh)
+}
+
+// TestWatchServiceWithClientClose tests the case where xDS responses are
+// received after the client is closed, and we make sure that the registered
+// watcher callback is not invoked.
+func TestWatchServiceWithClientClose(t *testing.T) {
+	fakeServer, cleanup, err := fakeserver.StartServer()
+	if err != nil {
+		t.Fatalf("Failed to start fake xDS server: %v", err)
+	}
+	defer cleanup()
+
+	xdsClient, err := New(clientOpts(fakeServer.Address))
+	if err != nil {
+		t.Fatalf("New returned error: %v", err)
+	}
+	defer xdsClient.Close()
+	t.Log("Created an xdsClient...")
+
+	callbackCh := testutils.NewChannel()
+	cancelWatch := xdsClient.WatchService(goodLDSTarget1, func(su ServiceUpdate, err error) {
+		callbackCh.Send(errors.New("watcher callback invoked after client close"))
+	})
+	defer cancelWatch()
+	t.Log("Registered a watcher for service updates...")
+
+	// Make the fakeServer send LDS response.
+	if _, err := fakeServer.XDSRequestChan.Receive(); err != nil {
+		t.Fatalf("Timeout expired when expecting an LDS request")
+	}
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: goodLDSResponse1}
+
+	xdsClient.Close()
+	t.Log("Closing the xdsClient...")
+
+	// Push an RDS response from the fakeserver
+	fakeServer.XDSResponseChan <- &fakeserver.Response{Resp: goodRDSResponse1}
+	if cbErr, err := callbackCh.Receive(); err != testutils.ErrRecvTimeout {
+		t.Fatal(cbErr)
+	}
+
+}