Golang context.TODO函数代码示例

// TestBlockProposal ensures that node will block proposal when it does not
// know who is the current leader; node will accept proposal when it knows
// who is the current leader.
func TestBlockProposal(t *testing.T) {
	n := newNode()
	r := newTestRaft(1, []uint64{1}, 10, 1, NewMemoryStorage())
	go n.run(r)
	defer n.Stop()

	errc := make(chan error, 1)
	go func() {
		errc <- n.Propose(context.TODO(), []byte("somedata"))
	}()

	testutil.WaitSchedule()
	select {
	case err := <-errc:
		t.Errorf("err = %v, want blocking", err)
	default:
	}

	n.Campaign(context.TODO())
	testutil.WaitSchedule()
	select {
	case err := <-errc:
		if err != nil {
			t.Errorf("err = %v, want %v", err, nil)
		}
	default:
		t.Errorf("blocking proposal, want unblocking")
	}
}

// TestNodePropose ensures that node.Propose sends the given proposal to the underlying raft.
func TestNodePropose(t *testing.T) {
	msgs := []raftpb.Message{}
	appendStep := func(r *raft, m raftpb.Message) {
		msgs = append(msgs, m)
	}

	n := newNode()
	s := NewMemoryStorage()
	r := newTestRaft(1, []uint64{1}, 10, 1, s)
	go n.run(r)
	n.Campaign(context.TODO())
	for {
		rd := <-n.Ready()
		s.Append(rd.Entries)
		// change the step function to appendStep until this raft becomes leader
		if rd.SoftState.Lead == r.id {
			r.step = appendStep
			n.Advance()
			break
		}
		n.Advance()
	}
	n.Propose(context.TODO(), []byte("somedata"))
	n.Stop()

	if len(msgs) != 1 {
		t.Fatalf("len(msgs) = %d, want %d", len(msgs), 1)
	}
	if msgs[0].Type != raftpb.MsgProp {
		t.Errorf("msg type = %d, want %d", msgs[0].Type, raftpb.MsgProp)
	}
	if !reflect.DeepEqual(msgs[0].Entries[0].Data, []byte("somedata")) {
		t.Errorf("data = %v, want %v", msgs[0].Entries[0].Data, []byte("somedata"))
	}
}

// TestMultiNodeProposeConfig ensures that multiNode.ProposeConfChange
// sends the given configuration proposal to the underlying raft.
func TestMultiNodeProposeConfig(t *testing.T) {
	mn := newMultiNode(1)
	go mn.run()
	s := NewMemoryStorage()
	mn.CreateGroup(1, newTestConfig(1, nil, 10, 1, s), []Peer{{ID: 1}})
	mn.Campaign(context.TODO(), 1)
	proposed := false
	var lastIndex uint64
	var ccdata []byte
	for {
		rds := <-mn.Ready()
		rd := rds[1]
		s.Append(rd.Entries)
		// change the step function to appendStep until this raft becomes leader
		if !proposed && rd.SoftState.Lead == mn.id {
			cc := raftpb.ConfChange{Type: raftpb.ConfChangeAddNode, NodeID: 1}
			var err error
			ccdata, err = cc.Marshal()
			if err != nil {
				t.Fatal(err)
			}
			mn.ProposeConfChange(context.TODO(), 1, cc)
			proposed = true
		}
		mn.Advance(rds)

		var err error
		lastIndex, err = s.LastIndex()
		if err != nil {
			t.Fatal(err)
		}
		if lastIndex >= 3 {
			break
		}
	}
	mn.Stop()

	entries, err := s.Entries(lastIndex, lastIndex+1, noLimit)
	if err != nil {
		t.Fatal(err)
	}
	if len(entries) != 1 {
		t.Fatalf("len(entries) = %d, want %d", len(entries), 1)
	}
	if entries[0].Type != raftpb.EntryConfChange {
		t.Fatalf("type = %v, want %v", entries[0].Type, raftpb.EntryConfChange)
	}
	if !bytes.Equal(entries[0].Data, ccdata) {
		t.Errorf("data = %v, want %v", entries[0].Data, ccdata)
	}
}

func BenchmarkProposal3Nodes(b *testing.B) {
	peers := []raft.Peer{{1, nil}, {2, nil}, {3, nil}}
	nt := newRaftNetwork(1, 2, 3)

	nodes := make([]*node, 0)

	for i := 1; i <= 3; i++ {
		n := startNode(uint64(i), peers, nt.nodeNetwork(uint64(i)))
		nodes = append(nodes, n)
	}
	// get ready and warm up
	time.Sleep(50 * time.Millisecond)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}

	for _, n := range nodes {
		if n.state.Commit != uint64(b.N+4) {
			continue
		}
	}
	b.StopTimer()

	for _, n := range nodes {
		n.stop()
	}
}

func (b *bee) createGroup() error {
	c := b.colony()
	if c.IsNil() || c.ID == Nil {
		return fmt.Errorf("%v is in no colony", b)
	}
	cfg := raft.GroupConfig{
		ID:             c.ID,
		Name:           b.String(),
		StateMachine:   b,
		Peers:          b.peers(),
		DataDir:        b.statePath(),
		SnapCount:      1024,
		FsyncTick:      b.hive.config.RaftFsyncTick,
		ElectionTicks:  b.hive.config.RaftElectTicks,
		HeartbeatTicks: b.hive.config.RaftHBTicks,
		MaxInFlights:   b.hive.config.RaftInFlights,
		MaxMsgSize:     b.hive.config.RaftMaxMsgSize,
	}
	if err := b.hive.node.CreateGroup(context.TODO(), cfg); err != nil {
		return err
	}

	if err := b.raftBarrier(); err != nil {
		return err
	}

	b.enableEmit()
	glog.V(2).Infof("%v started its raft node", b)
	return nil
}

func TestBasicProgress(t *testing.T) {
	peers := []raft.Peer{{1, nil}, {2, nil}, {3, nil}, {4, nil}, {5, nil}}
	nt := newRaftNetwork(1, 2, 3, 4, 5)

	nodes := make([]*node, 0)

	for i := 1; i <= 5; i++ {
		n := startNode(uint64(i), peers, nt.nodeNetwork(uint64(i)))
		nodes = append(nodes, n)
	}

	time.Sleep(10 * time.Millisecond)

	for i := 0; i < 10000; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}

	time.Sleep(500 * time.Millisecond)
	for _, n := range nodes {
		n.stop()
		if n.state.Commit != 10006 {
			t.Errorf("commit = %d, want = 10006", n.state.Commit)
		}
	}
}

// TestNodeStep ensures that node.Step sends msgProp to propc chan
// and other kinds of messages to recvc chan.
func TestNodeStep(t *testing.T) {
	for i, msgn := range raftpb.MessageType_name {
		n := &node{
			propc: make(chan raftpb.Message, 1),
			recvc: make(chan raftpb.Message, 1),
		}
		msgt := raftpb.MessageType(i)
		n.Step(context.TODO(), raftpb.Message{Type: msgt})
		// Proposal goes to proc chan. Others go to recvc chan.
		if msgt == raftpb.MsgProp {
			select {
			case <-n.propc:
			default:
				t.Errorf("%d: cannot receive %s on propc chan", msgt, msgn)
			}
		} else {
			if msgt == raftpb.MsgBeat || msgt == raftpb.MsgHup || msgt == raftpb.MsgUnreachable || msgt == raftpb.MsgSnapStatus {
				select {
				case <-n.recvc:
					t.Errorf("%d: step should ignore %s", msgt, msgn)
				default:
				}
			} else {
				select {
				case <-n.recvc:
				default:
					t.Errorf("%d: cannot receive %s on recvc chan", msgt, msgn)
				}
			}
		}
	}
}

func (n *node) start() {
	n.stopc = make(chan struct{})
	ticker := time.Tick(5 * time.Millisecond)

	go func() {
		for {
			select {
			case <-ticker:
				n.Tick()
			case rd := <-n.Ready():
				if !raft.IsEmptyHardState(rd.HardState) {
					n.state = rd.HardState
					n.storage.SetHardState(n.state)
				}
				n.storage.Append(rd.Entries)
				time.Sleep(time.Millisecond)
				// TODO: make send async, more like real world...
				for _, m := range rd.Messages {
					n.iface.send(m)
				}
				n.Advance()
			case m := <-n.iface.recv():
				n.Step(context.TODO(), m)
			case <-n.stopc:
				n.Stop()
				log.Printf("raft.%d: stop", n.id)
				n.Node = nil
				close(n.stopc)
				return
			case p := <-n.pausec:
				recvms := make([]raftpb.Message, 0)
				for p {
					select {
					case m := <-n.iface.recv():
						recvms = append(recvms, m)
					case p = <-n.pausec:
					}
				}
				// step all pending messages
				for _, m := range recvms {
					n.Step(context.TODO(), m)
				}
			}
		}
	}()
}

// TestMultiNodePropose ensures that node.Propose sends the given proposal to the underlying raft.
func TestMultiNodePropose(t *testing.T) {
	mn := newMultiNode(1)
	go mn.run()
	s := NewMemoryStorage()
	mn.CreateGroup(1, newTestConfig(1, nil, 10, 1, s), []Peer{{ID: 1}})
	mn.Campaign(context.TODO(), 1)
	proposed := false
	for {
		rds := <-mn.Ready()
		rd := rds[1]
		s.Append(rd.Entries)
		// Once we are the leader, propose a command.
		if !proposed && rd.SoftState.Lead == mn.id {
			mn.Propose(context.TODO(), 1, []byte("somedata"))
			proposed = true
		}
		mn.Advance(rds)

		// Exit when we have three entries: one ConfChange, one no-op for the election,
		// and our proposed command.
		lastIndex, err := s.LastIndex()
		if err != nil {
			t.Fatal(err)
		}
		if lastIndex >= 3 {
			break
		}
	}
	mn.Stop()

	lastIndex, err := s.LastIndex()
	if err != nil {
		t.Fatal(err)
	}
	entries, err := s.Entries(lastIndex, lastIndex+1, noLimit)
	if err != nil {
		t.Fatal(err)
	}
	if len(entries) != 1 {
		t.Fatalf("len(entries) = %d, want %d", len(entries), 1)
	}
	if !bytes.Equal(entries[0].Data, []byte("somedata")) {
		t.Errorf("entries[0].Data = %v, want %v", entries[0].Data, []byte("somedata"))
	}
}

// TestProposeUnknownGroup ensures that we gracefully handle proposals
// for groups we don't know about (which can happen on a former leader
// that has been removed from the group).
//
// It is analogous to TestBlockProposal from node_test.go but in
// MultiNode we cannot block proposals based on individual group
// leader status.
func TestProposeUnknownGroup(t *testing.T) {
	mn := newMultiNode(1)
	go mn.run()
	defer mn.Stop()

	// A nil error from Propose() doesn't mean much. In this case the
	// proposal will be dropped on the floor because we don't know
	// anything about group 42. This is a very crude test that mainly
	// guarantees that we don't panic in this case.
	if err := mn.Propose(context.TODO(), 42, []byte("somedata")); err != nil {
		t.Errorf("err = %v, want nil", err)
	}
}

func TestPause(t *testing.T) {
	peers := []raft.Peer{{1, nil}, {2, nil}, {3, nil}, {4, nil}, {5, nil}}
	nt := newRaftNetwork(1, 2, 3, 4, 5)

	nodes := make([]*node, 0)

	for i := 1; i <= 5; i++ {
		n := startNode(uint64(i), peers, nt.nodeNetwork(uint64(i)))
		nodes = append(nodes, n)
	}

	time.Sleep(50 * time.Millisecond)
	for i := 0; i < 300; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}
	nodes[1].pause()
	for i := 0; i < 300; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}
	nodes[2].pause()
	for i := 0; i < 300; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}
	nodes[2].resume()
	for i := 0; i < 300; i++ {
		nodes[0].Propose(context.TODO(), []byte("somedata"))
	}
	nodes[1].resume()

	// give some time for nodes to catch up with the raft leader
	time.Sleep(300 * time.Millisecond)
	for _, n := range nodes {
		n.stop()
		if n.state.Commit != 1206 {
			t.Errorf("commit = %d, want = 1206", n.state.Commit)
		}
	}
}

func (h *HelloHTTPHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	name, ok := vars["name"]
	if !ok {
		http.Error(w, "no name", http.StatusBadRequest)
		return
	}

	res, err := beehive.Sync(context.TODO(), HelloHTTP{Name: name})
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	fmt.Fprintf(w, "hello %s (%d)\n", name, res.(int))
}

func (h *hive) handleCmd(cc cmdAndChannel) {
	glog.V(2).Infof("%v handles cmd %+v", h, cc.cmd)
	switch d := cc.cmd.Data.(type) {
	case cmdStop:
		// TODO(soheil): This has a race with Stop(). Use atomics here.
		h.status = hiveStopped
		h.stopListener()
		h.stopQees()
		h.node.Stop()
		cc.ch <- cmdResult{}

	case cmdPing:
		cc.ch <- cmdResult{}

	case cmdSync:
		err := h.raftBarrier()
		cc.ch <- cmdResult{Err: err}

	case cmdNewHiveID:
		r, err := h.node.ProposeRetry(hiveGroup, newHiveID{},
			h.config.RaftElectTimeout(), 10)
		cc.ch <- cmdResult{
			Data: r,
			Err:  err,
		}

	case cmdAddHive:
		err := h.node.AddNodeToGroup(context.TODO(), d.Hive.ID, hiveGroup,
			d.Hive.Addr)
		cc.ch <- cmdResult{
			Err: err,
		}

	case cmdLiveHives:
		cc.ch <- cmdResult{
			Data: h.registry.hives(),
		}

	default:
		cc.ch <- cmdResult{
			Err: ErrInvalidCmd,
		}
	}
}

func defaultHTTPHandler(w http.ResponseWriter, r *http.Request, h bh.Hive) {
	w.Header().Set("Server", "Beehive-netctrl-HTTP-Server")

	vars := mux.Vars(r)

	submodule, ok := vars["submodule"]
	if !ok {
		/* This should not happened :) */
		http.Error(w, "Invalid request", http.StatusBadRequest)
		return
	}

	verb, ok := vars["verb"]
	if !ok {
		/* This should not happened :) */
		http.Error(w, "Invalid request", http.StatusBadRequest)
		return
	}

	creq := HTTPRequest{
		AppName: submodule,
		Verb:    verb,
	}

	// Read content data if available :)
	if r.ContentLength > 0 {
		data, err := ioutil.ReadAll(r.Body)
		if err == nil {
			creq.Data = data
		}
	}

	cres, err := h.Sync(context.TODO(), creq)
	if err == nil && cres != nil {
		w.Write(cres.(HTTPResponse).Data)
		w.WriteHeader(http.StatusOK)
		return
	} else {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		fmt.Errorf("defaultTTPHandler: %v\n", err)
		return
	}

}

// Cancel and Stop should unblock Step()
func TestNodeStepUnblock(t *testing.T) {
	// a node without buffer to block step
	n := &node{
		propc: make(chan raftpb.Message),
		done:  make(chan struct{}),
	}

	ctx, cancel := context.WithCancel(context.Background())
	stopFunc := func() { close(n.done) }

	tests := []struct {
		unblock func()
		werr    error
	}{
		{stopFunc, ErrStopped},
		{cancel, context.Canceled},
	}

	for i, tt := range tests {
		errc := make(chan error, 1)
		go func() {
			err := n.Step(ctx, raftpb.Message{Type: raftpb.MsgProp})
			errc <- err
		}()
		tt.unblock()
		select {
		case err := <-errc:
			if err != tt.werr {
				t.Errorf("#%d: err = %v, want %v", i, err, tt.werr)
			}
			//clean up side-effect
			if ctx.Err() != nil {
				ctx = context.TODO()
			}
			select {
			case <-n.done:
				n.done = make(chan struct{})
			default:
			}
		case <-time.After(time.Millisecond * 100):
			t.Errorf("#%d: failed to unblock step", i)
		}
	}
}