Golang context.Background函数代码示例

func (h *keysHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if !allowMethod(w, r.Method, "HEAD", "GET", "PUT", "POST", "DELETE") {
		return
	}
	w.Header().Set("X-Etcd-Cluster-ID", h.clusterInfo.ID().String())

	ctx, cancel := context.WithTimeout(context.Background(), h.timeout)
	defer cancel()

	rr, err := parseKeyRequest(r, clockwork.NewRealClock())
	if err != nil {
		writeError(w, err)
		return
	}

	resp, err := h.server.Do(ctx, rr)
	if err != nil {
		err = trimErrorPrefix(err, etcdserver.StoreKeysPrefix)
		writeError(w, err)
		return
	}
	switch {
	case resp.Event != nil:
		if err := writeKeyEvent(w, resp.Event, h.timer); err != nil {
			// Should never be reached
			log.Printf("error writing event: %v", err)
		}
	case resp.Watcher != nil:
		ctx, cancel := context.WithTimeout(context.Background(), defaultWatchTimeout)
		defer cancel()
		handleKeyWatch(ctx, w, resp.Watcher, rr.Stream, h.timer)
	default:
		writeError(w, errors.New("received response with no Event/Watcher!"))
	}
}

func TestClientWithMisbehavedServer(t *testing.T) {
	server, ct := setUp(t, 0, math.MaxUint32, misbehaved)
	callHdr := &CallHdr{
		Host:   "localhost",
		Method: "foo",
	}
	conn, ok := ct.(*http2Client)
	if !ok {
		t.Fatalf("Failed to convert %v to *http2Client", ct)
	}
	// Test the logic for the violation of stream flow control window size restriction.
	s, err := ct.NewStream(context.Background(), callHdr)
	if err != nil {
		t.Fatalf("Failed to open stream: %v", err)
	}
	if err := ct.Write(s, expectedRequest, &Options{Last: true, Delay: false}); err != nil {
		t.Fatalf("Failed to write: %v", err)
	}
	// Read without window update.
	for {
		p := make([]byte, http2MaxFrameLen)
		if _, err = s.dec.Read(p); err != nil {
			break
		}
	}
	if s.fc.pendingData != initialWindowSize || s.fc.pendingUpdate != 0 || conn.fc.pendingData != initialWindowSize || conn.fc.pendingUpdate != 0 {
		t.Fatalf("Client mistakenly updates inbound flow control params: got %d, %d, %d, %d; want %d, %d, %d, %d", s.fc.pendingData, s.fc.pendingUpdate, conn.fc.pendingData, conn.fc.pendingUpdate, initialWindowSize, 0, initialWindowSize, 0)
	}
	if err != io.EOF || s.statusCode != codes.Internal {
		t.Fatalf("Got err %v and the status code %d, want <EOF> and the code %d", err, s.statusCode, codes.Internal)
	}
	conn.CloseStream(s, err)
	if s.fc.pendingData != 0 || s.fc.pendingUpdate != 0 || conn.fc.pendingData != 0 || conn.fc.pendingUpdate != initialWindowSize {
		t.Fatalf("Client mistakenly resets inbound flow control params: got %d, %d, %d, %d; want 0, 0, 0, %d", s.fc.pendingData, s.fc.pendingUpdate, conn.fc.pendingData, conn.fc.pendingUpdate, initialWindowSize)
	}
	// Test the logic for the violation of the connection flow control window size restriction.
	//
	// Generate enough streams to drain the connection window.
	callHdr = &CallHdr{
		Host:   "localhost",
		Method: "foo.MaxFrame",
	}
	for i := 0; i < int(initialConnWindowSize/initialWindowSize+10); i++ {
		s, err := ct.NewStream(context.Background(), callHdr)
		if err != nil {
			break
		}
		if err := ct.Write(s, expectedRequest, &Options{Last: true, Delay: false}); err != nil {
			break
		}
	}
	// http2Client.errChan is closed due to connection flow control window size violation.
	<-conn.Error()
	ct.Close()
	server.stop()
}

func (d *discovery) checkCluster() ([]*client.Node, int, uint64, error) {
	configKey := path.Join("/", d.cluster, "_config")
	ctx, cancel := context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
	// find cluster size
	resp, err := d.c.Get(ctx, path.Join(configKey, "size"), nil)
	cancel()
	if err != nil {
		if eerr, ok := err.(*client.Error); ok && eerr.Code == client.ErrorCodeKeyNotFound {
			return nil, 0, 0, ErrSizeNotFound
		}
		if err == client.ErrInvalidJSON {
			return nil, 0, 0, ErrBadDiscoveryEndpoint
		}
		if ce, ok := err.(*client.ClusterError); ok {
			plog.Error(ce.Detail())
			return d.checkClusterRetry()
		}
		return nil, 0, 0, err
	}
	size, err := strconv.Atoi(resp.Node.Value)
	if err != nil {
		return nil, 0, 0, ErrBadSizeKey
	}

	ctx, cancel = context.WithTimeout(context.Background(), client.DefaultRequestTimeout)
	resp, err = d.c.Get(ctx, d.cluster, nil)
	cancel()
	if err != nil {
		if ce, ok := err.(*client.ClusterError); ok {
			plog.Error(ce.Detail())
			return d.checkClusterRetry()
		}
		return nil, 0, 0, err
	}
	nodes := make([]*client.Node, 0)
	// append non-config keys to nodes
	for _, n := range resp.Node.Nodes {
		if !(path.Base(n.Key) == path.Base(configKey)) {
			nodes = append(nodes, n)
		}
	}

	snodes := sortableNodes{nodes}
	sort.Sort(snodes)

	// find self position
	for i := range nodes {
		if path.Base(nodes[i].Key) == path.Base(d.selfKey()) {
			break
		}
		if i >= size-1 {
			return nodes[:size], size, resp.Index, ErrFullCluster
		}
	}
	return nodes, size, resp.Index, nil
}

func runStream(b *testing.B, maxConcurrentCalls int) {
	s := stats.AddStats(b, 38)
	b.StopTimer()
	target, stopper := StartServer("localhost:0")
	defer stopper()
	conn := NewClientConn(target)
	tc := testpb.NewTestServiceClient(conn)

	// Warm up connection.
	stream, err := tc.StreamingCall(context.Background())
	if err != nil {
		grpclog.Fatalf("%v.StreamingCall(_) = _, %v", tc, err)
	}
	for i := 0; i < 10; i++ {
		streamCaller(tc, stream)
	}

	ch := make(chan int, maxConcurrentCalls*4)
	var (
		mu sync.Mutex
		wg sync.WaitGroup
	)
	wg.Add(maxConcurrentCalls)

	// Distribute the b.N calls over maxConcurrentCalls workers.
	for i := 0; i < maxConcurrentCalls; i++ {
		go func() {
			stream, err := tc.StreamingCall(context.Background())
			if err != nil {
				grpclog.Fatalf("%v.StreamingCall(_) = _, %v", tc, err)
			}
			for _ = range ch {
				start := time.Now()
				streamCaller(tc, stream)
				elapse := time.Since(start)
				mu.Lock()
				s.Add(elapse)
				mu.Unlock()
			}
			wg.Done()
		}()
	}
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		ch <- i
	}
	b.StopTimer()
	close(ch)
	wg.Wait()
	conn.Close()
}

func TestHTTPKeysAPIGetResponse(t *testing.T) {
	client := &staticHTTPClient{
		resp: http.Response{
			StatusCode: http.StatusOK,
			Header:     http.Header{"X-Etcd-Index": []string{"42"}},
		},
		body: []byte(`{"action":"get","node":{"key":"/pants/foo/bar","modifiedIndex":25,"createdIndex":19,"nodes":[{"key":"/pants/foo/bar/baz","value":"snarf","createdIndex":21,"modifiedIndex":25}]}}`),
	}

	wantResponse := &Response{
		Action: "get",
		Node: &Node{
			Key: "/pants/foo/bar",
			Nodes: []*Node{
				&Node{Key: "/pants/foo/bar/baz", Value: "snarf", CreatedIndex: 21, ModifiedIndex: 25},
			},
			CreatedIndex:  uint64(19),
			ModifiedIndex: uint64(25),
		},
		Index: uint64(42),
	}

	kAPI := &httpKeysAPI{client: client, prefix: "/pants"}
	resp, err := kAPI.Get(context.Background(), "/foo/bar", &GetOptions{Recursive: true})
	if err != nil {
		t.Errorf("non-nil error: %#v", err)
	}
	if !reflect.DeepEqual(wantResponse, resp) {
		t.Errorf("incorrect Response: want=%#v got=%#v", wantResponse, resp)
	}
}

func TestNodeAdvance(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	storage := NewMemoryStorage()
	c := &Config{
		ID:              1,
		ElectionTick:    10,
		HeartbeatTick:   1,
		Storage:         storage,
		MaxSizePerMsg:   noLimit,
		MaxInflightMsgs: 256,
	}
	n := StartNode(c, []Peer{{ID: 1}})
	n.Campaign(ctx)
	<-n.Ready()
	n.Propose(ctx, []byte("foo"))
	var rd Ready
	select {
	case rd = <-n.Ready():
		t.Fatalf("unexpected Ready before Advance: %+v", rd)
	case <-time.After(time.Millisecond):
	}
	storage.Append(rd.Entries)
	n.Advance()
	select {
	case <-n.Ready():
	case <-time.After(time.Millisecond):
		t.Errorf("expect Ready after Advance, but there is no Ready available")
	}
}

func TestLargeMessage(t *testing.T) {
	server, ct := setUp(t, 0, math.MaxUint32, normal)
	callHdr := &CallHdr{
		Host:   "localhost",
		Method: "foo.Large",
	}
	var wg sync.WaitGroup
	for i := 0; i < 2; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()
			s, err := ct.NewStream(context.Background(), callHdr)
			if err != nil {
				t.Errorf("failed to open stream: %v", err)
			}
			if err := ct.Write(s, expectedRequestLarge, &Options{Last: true, Delay: false}); err != nil {
				t.Errorf("failed to send data: %v", err)
			}
			p := make([]byte, len(expectedResponseLarge))
			_, recvErr := io.ReadFull(s, p)
			if recvErr != nil || !bytes.Equal(p, expectedResponseLarge) {
				t.Errorf("Error: %v, want <nil>; Result len: %d, want len %d", recvErr, len(p), len(expectedResponseLarge))
			}
			_, recvErr = io.ReadFull(s, p)
			if recvErr != io.EOF {
				t.Errorf("Error: %v; want <EOF>", recvErr)
			}
		}()
	}
	wg.Wait()
	ct.Close()
	server.stop()
}

func (d *discovery) waitNodes(nodes []*client.Node, size int, index uint64) ([]*client.Node, error) {
	if len(nodes) > size {
		nodes = nodes[:size]
	}
	// watch from the next index
	w := d.c.Watcher(d.cluster, &client.WatcherOptions{AfterIndex: index, Recursive: true})
	all := make([]*client.Node, len(nodes))
	copy(all, nodes)
	for _, n := range all {
		if path.Base(n.Key) == path.Base(d.selfKey()) {
			plog.Noticef("found self %s in the cluster", path.Base(d.selfKey()))
		} else {
			plog.Noticef("found peer %s in the cluster", path.Base(n.Key))
		}
	}

	// wait for others
	for len(all) < size {
		plog.Noticef("found %d peer(s), waiting for %d more", len(all), size-len(all))
		resp, err := w.Next(context.Background())
		if err != nil {
			if ce, ok := err.(*client.ClusterError); ok {
				plog.Error(ce.Detail())
				return d.waitNodesRetry()
			}
			return nil, err
		}
		plog.Noticef("found peer %s in the cluster", path.Base(resp.Node.Key))
		all = append(all, resp.Node)
	}
	plog.Noticef("found %d needed peer(s)", len(all))
	return all, nil
}

func testExceedMaxStreamsLimit(t *testing.T, e env) {
	// Only allows 1 live stream per server transport.
	s, cc := setUp(nil, 1, "", e)
	tc := testpb.NewTestServiceClient(cc)
	defer tearDown(s, cc)
	done := make(chan struct{})
	ch := make(chan int)
	go func() {
		for {
			select {
			case <-time.After(5 * time.Millisecond):
				ch <- 0
			case <-time.After(5 * time.Second):
				close(done)
				return
			}
		}
	}()
	// Loop until a stream creation hangs due to the new max stream setting.
	for {
		select {
		case <-ch:
			ctx, _ := context.WithTimeout(context.Background(), time.Second)
			if _, err := tc.StreamingInputCall(ctx); err != nil {
				if grpc.Code(err) == codes.DeadlineExceeded {
					return
				}
				t.Fatalf("%v.StreamingInputCall(_) = %v, want <nil>", tc, err)
			}
		case <-done:
			t.Fatalf("Client has not received the max stream setting in 5 seconds.")
		}
	}
}

func testClientStreaming(t *testing.T, e env) {
	s, cc := setUp(nil, math.MaxUint32, "", e)
	tc := testpb.NewTestServiceClient(cc)
	defer tearDown(s, cc)
	stream, err := tc.StreamingInputCall(context.Background())
	if err != nil {
		t.Fatalf("%v.StreamingInputCall(_) = _, %v, want <nil>", tc, err)
	}
	var sum int
	for _, s := range reqSizes {
		pl := newPayload(testpb.PayloadType_COMPRESSABLE, int32(s))
		req := &testpb.StreamingInputCallRequest{
			Payload: pl,
		}
		if err := stream.Send(req); err != nil {
			t.Fatalf("%v.Send(%v) = %v, want <nil>", stream, req, err)
		}
		sum += s
	}
	reply, err := stream.CloseAndRecv()
	if err != nil {
		t.Fatalf("%v.CloseAndRecv() got error %v, want %v", stream, err, nil)
	}
	if reply.GetAggregatedPayloadSize() != int32(sum) {
		t.Fatalf("%v.CloseAndRecv().GetAggregatePayloadSize() = %v; want %v", stream, reply.GetAggregatedPayloadSize(), sum)
	}
}

func testEmptyUnaryWithUserAgent(t *testing.T, e env) {
	s, cc := setUp(nil, math.MaxUint32, testAppUA, e)
	// Wait until cc is connected.
	if ok := cc.WaitForStateChange(time.Second, grpc.Idle); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Idle, ok)
	}
	if ok := cc.WaitForStateChange(10*time.Second, grpc.Connecting); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Connecting, ok)
	}
	if cc.State() != grpc.Ready {
		t.Fatalf("cc.State() = %s, want %s", cc.State(), grpc.Ready)
	}
	if ok := cc.WaitForStateChange(time.Second, grpc.Ready); ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want false", grpc.Ready, ok)
	}
	tc := testpb.NewTestServiceClient(cc)
	var header metadata.MD
	reply, err := tc.EmptyCall(context.Background(), &testpb.Empty{}, grpc.Header(&header))
	if err != nil || !proto.Equal(&testpb.Empty{}, reply) {
		t.Fatalf("TestService/EmptyCall(_, _) = %v, %v, want %v, <nil>", reply, err, &testpb.Empty{})
	}
	if v, ok := header["ua"]; !ok || v[0] != testAppUA {
		t.Fatalf("header[\"ua\"] = %q, %t, want %q, true", v, ok, testAppUA)
	}
	tearDown(s, cc)
	if ok := cc.WaitForStateChange(5*time.Second, grpc.Ready); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Ready, ok)
	}
	if cc.State() != grpc.Shutdown {
		t.Fatalf("cc.State() = %s, want %s", cc.State(), grpc.Shutdown)
	}
}

func testTimeoutOnDeadServer(t *testing.T, e env) {
	s, cc := setUp(nil, math.MaxUint32, "", e)
	tc := testpb.NewTestServiceClient(cc)
	if ok := cc.WaitForStateChange(time.Second, grpc.Idle); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Idle, ok)
	}
	if ok := cc.WaitForStateChange(time.Second, grpc.Connecting); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Connecting, ok)
	}
	if cc.State() != grpc.Ready {
		t.Fatalf("cc.State() = %s, want %s", cc.State(), grpc.Ready)
	}
	if ok := cc.WaitForStateChange(time.Millisecond, grpc.Ready); ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want false", grpc.Ready, ok)
	}
	s.Stop()
	// Set -1 as the timeout to make sure if transportMonitor gets error
	// notification in time the failure path of the 1st invoke of
	// ClientConn.wait hits the deadline exceeded error.
	ctx, _ := context.WithTimeout(context.Background(), -1)
	if _, err := tc.EmptyCall(ctx, &testpb.Empty{}); grpc.Code(err) != codes.DeadlineExceeded {
		t.Fatalf("TestService/EmptyCall(%v, _) = _, error %v, want _, error code: %d", ctx, err, codes.DeadlineExceeded)
	}
	if ok := cc.WaitForStateChange(time.Second, grpc.Ready); !ok {
		t.Fatalf("cc.WaitForStateChange(_, %s) = %t, want true", grpc.Ready, ok)
	}
	state := cc.State()
	if state != grpc.Connecting && state != grpc.TransientFailure {
		t.Fatalf("cc.State() = %s, want %s or %s", state, grpc.Connecting, grpc.TransientFailure)
	}
	cc.Close()
}

func TestHTTPMembersAPIListError(t *testing.T) {
	tests := []httpClient{
		// generic httpClient failure
		&staticHTTPClient{err: errors.New("fail!")},

		// unrecognized HTTP status code
		&staticHTTPClient{
			resp: http.Response{StatusCode: http.StatusTeapot},
		},

		// fail to unmarshal body on StatusOK
		&staticHTTPClient{
			resp: http.Response{
				StatusCode: http.StatusOK,
			},
			body: []byte(`[{"id":"XX`),
		},
	}

	for i, tt := range tests {
		mAPI := &httpMembersAPI{client: tt}
		ms, err := mAPI.List(context.Background())
		if err == nil {
			t.Errorf("#%d: got nil err", i)
		}
		if ms != nil {
			t.Errorf("#%d: got non-nil Member slice", i)
		}
	}
}

func TestHTTPMembersAPIListSuccess(t *testing.T) {
	wantAction := &membersAPIActionList{}
	mAPI := &httpMembersAPI{
		client: &actionAssertingHTTPClient{
			t:   t,
			act: wantAction,
			resp: http.Response{
				StatusCode: http.StatusOK,
			},
			body: []byte(`{"members":[{"id":"94088180e21eb87b","name":"node2","peerURLs":["http://127.0.0.1:7002"],"clientURLs":["http://127.0.0.1:4002"]}]}`),
		},
	}

	wantResponseMembers := []Member{
		Member{
			ID:         "94088180e21eb87b",
			Name:       "node2",
			PeerURLs:   []string{"http://127.0.0.1:7002"},
			ClientURLs: []string{"http://127.0.0.1:4002"},
		},
	}

	m, err := mAPI.List(context.Background())
	if err != nil {
		t.Errorf("got non-nil err: %#v", err)
	}
	if !reflect.DeepEqual(wantResponseMembers, m) {
		t.Errorf("incorrect Members: want=%#v got=%#v", wantResponseMembers, m)
	}
}

func BenchmarkOneNode(b *testing.B) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	n := newNode()
	s := NewMemoryStorage()
	r := newTestRaft(1, []uint64{1}, 10, 1, s)
	go n.run(r)

	defer n.Stop()

	n.Campaign(ctx)
	go func() {
		for i := 0; i < b.N; i++ {
			n.Propose(ctx, []byte("foo"))
		}
	}()

	for {
		rd := <-n.Ready()
		s.Append(rd.Entries)
		// a reasonable disk sync latency
		time.Sleep(1 * time.Millisecond)
		n.Advance()
		if rd.HardState.Commit == uint64(b.N+1) {
			return
		}
	}
}