Golang raft.RestartNode函数代码示例

// Start implements replication.LogReplicator
func (l *raftLog) Start(lo uint64) error {
	inited, err := l.config.Storage.(*raftStorage).IsInitialized()
	if err != nil {
		return err
	}
	if inited {
		l.config.Applied = lo
		l.node = raft.RestartNode(&l.config)
	} else {
		if lo != 0 {
			log.Panicf("storage uninitialized but state machine not fresh: lo = %d", lo)
		}
		// Add a dummy first entry
		hardState, confState, err := l.config.Storage.InitialState()
		if err != nil {
			return err
		}
		confNodes := make([]raft.Peer, 0, len(confState.Nodes))
		for _, id := range confState.Nodes {
			confNodes = append(confNodes, raft.Peer{ID: id})
		}
		l.config.Storage.(*raftStorage).save(hardState, make([]raftpb.Entry, 1))
		l.node = raft.StartNode(&l.config, confNodes)
	}

	l.leaderHintSet = make(chan bool, COMMITTED_BUFFER)
	l.waitCommitted = make(chan replication.LogEntry, COMMITTED_BUFFER)
	l.stop = make(chan struct{})
	l.stopped = make(chan struct{})
	l.grpcDropClient = make(chan uint64)
	l.grpcClientCache = make(map[uint64]proto.RaftClient)

	go l.run()
	return nil
}

// restart restarts the node. restart a started node
// blocks and might affect the future stop operation.
func (n *node) restart() {
	// wait for the shutdown
	<-n.stopc
	n.Node = raft.RestartNode(n.id, 10, 1, n.storage, 0)
	n.start()
	n.iface.connect()
}

func restartNode(cfg *ServerConfig, snapshot *raftpb.Snapshot) (types.ID, *cluster, raft.Node, *raftStorage, *wal.WAL) {
	var walsnap walpb.Snapshot
	if snapshot != nil {
		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
	}
	w, id, cid, st, ents := readWAL(cfg.WALDir(), walsnap)

	plog.Infof("restarting member %s in cluster %s at commit index %d", id, cid, st.Commit)
	cl := newCluster("")
	cl.SetID(cid)
	s := newRaftStorage()
	if snapshot != nil {
		s.ApplySnapshot(*snapshot)
	}
	s.SetHardState(st)
	s.Append(ents)
	c := &raft.Config{
		ID:              uint64(id),
		ElectionTick:    cfg.ElectionTicks,
		HeartbeatTick:   1,
		Storage:         s,
		MaxSizePerMsg:   maxSizePerMsg,
		MaxInflightMsgs: maxInflightMsgs,
	}
	n := raft.RestartNode(c)
	raftStatus = n.Status
	advanceTicksForElection(n, c.ElectionTick)
	return id, cl, n, s, w
}

// InitAndStartNode gets called after having at least one membership sync with the cluster.
func (n *node) InitAndStartNode(wal *raftwal.Wal) {
	restart, err := n.initFromWal(wal)
	x.Check(err)

	if restart {
		fmt.Printf("RESTARTING\n")
		n.raft = raft.RestartNode(n.cfg)

	} else {
		if groups().HasPeer(n.gid) {
			n.joinPeers()
			n.raft = raft.StartNode(n.cfg, nil)

		} else {
			peers := []raft.Peer{{ID: n.id}}
			n.raft = raft.StartNode(n.cfg, peers)
			// Trigger election, so this node can become the leader of this single-node cluster.
			n.canCampaign = true
		}
	}
	go n.processCommitCh()
	go n.Run()
	// TODO: Find a better way to snapshot, so we don't lose the membership
	// state information, which isn't persisted.
	// go n.snapshotPeriodically()
	go n.batchAndSendMessages()
}

func (rc *raftNode) startRaft() {
	if !fileutil.Exist(rc.snapdir) {
		if err := os.Mkdir(rc.snapdir, 0750); err != nil {
			log.Fatalf("raftexample: cannot create dir for snapshot (%v)", err)
		}
	}
	rc.snapshotter = snap.New(rc.snapdir)
	rc.snapshotterReady <- rc.snapshotter

	oldwal := wal.Exist(rc.waldir)
	rc.wal = rc.replayWAL()

	rpeers := make([]raft.Peer, len(rc.peers))
	for i := range rpeers {
		rpeers[i] = raft.Peer{ID: uint64(i + 1)}
	}
	c := &raft.Config{
		ID:              uint64(rc.id),
		ElectionTick:    10,
		HeartbeatTick:   1,
		Storage:         rc.raftStorage,
		MaxSizePerMsg:   1024 * 1024,
		MaxInflightMsgs: 256,
	}

	if oldwal {
		rc.node = raft.RestartNode(c)
	} else {
		startPeers := rpeers
		if rc.join {
			startPeers = nil
		}
		rc.node = raft.StartNode(c, startPeers)
	}

	ss := &stats.ServerStats{}
	ss.Initialize()

	rc.transport = &rafthttp.Transport{
		ID:          types.ID(rc.id),
		ClusterID:   0x1000,
		Raft:        rc,
		ServerStats: ss,
		LeaderStats: stats.NewLeaderStats(strconv.Itoa(rc.id)),
		ErrorC:      make(chan error),
	}

	rc.transport.Start()
	for i := range rc.peers {
		if i+1 != rc.id {
			rc.transport.AddPeer(types.ID(i+1), []string{rc.peers[i]})
		}
	}

	go rc.serveRaft()
	go rc.serveChannels()
}

func (n *Node) loadAndStart(ctx context.Context, forceNewCluster bool) error {
	walDir := n.walDir()
	snapDir := n.snapDir()

	if err := os.MkdirAll(snapDir, 0700); err != nil {
		return fmt.Errorf("create snapshot directory error: %v", err)
	}

	// Create a snapshotter
	n.snapshotter = snap.New(snapDir)

	if !wal.Exist(walDir) {
		raftNode := &api.RaftMember{
			RaftID: n.Config.ID,
			Addr:   n.Address,
		}
		metadata, err := raftNode.Marshal()
		if err != nil {
			return fmt.Errorf("error marshalling raft node: %v", err)
		}
		n.wal, err = wal.Create(walDir, metadata)
		if err != nil {
			return fmt.Errorf("create wal error: %v", err)
		}

		n.cluster.AddMember(&membership.Member{RaftMember: raftNode})
		n.startNodePeers = []raft.Peer{{ID: n.Config.ID, Context: metadata}}

		return nil
	}

	// Load snapshot data
	snapshot, err := n.snapshotter.Load()
	if err != nil && err != snap.ErrNoSnapshot {
		return err
	}

	if snapshot != nil {
		// Load the snapshot data into the store
		if err := n.restoreFromSnapshot(snapshot.Data, forceNewCluster); err != nil {
			return err
		}
	}

	// Read logs to fully catch up store
	if err := n.readWAL(ctx, snapshot, forceNewCluster); err != nil {
		return err
	}

	n.Node = raft.RestartNode(n.Config)
	return nil
}

func restartNode(cfg *ServerConfig, index uint64, snapshot *raftpb.Snapshot) (types.ID, raft.Node, *raft.MemoryStorage, *wal.WAL) {
	w, id, cid, st, ents := readWAL(cfg.WALDir(), index)
	cfg.Cluster.SetID(cid)

	log.Printf("etcdserver: restart member %s in cluster %s at commit index %d", id, cfg.Cluster.ID(), st.Commit)
	s := raft.NewMemoryStorage()
	if snapshot != nil {
		s.ApplySnapshot(*snapshot)
	}
	s.SetHardState(st)
	s.Append(ents)
	n := raft.RestartNode(uint64(id), 10, 1, s)
	return id, n, s, w
}

func restartAsStandaloneNode(cfg *ServerConfig, snapshot *raftpb.Snapshot) (types.ID, *cluster, raft.Node, *raftStorage, *wal.WAL) {
	var walsnap walpb.Snapshot
	if snapshot != nil {
		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
	}
	w, id, cid, st, ents := readWAL(cfg.WALDir(), walsnap)

	// discard the previously uncommitted entries
	for i, ent := range ents {
		if ent.Index > st.Commit {
			plog.Infof("discarding %d uncommitted WAL entries ", len(ents)-i)
			ents = ents[:i]
			break
		}
	}

	// force append the configuration change entries
	toAppEnts := createConfigChangeEnts(getIDs(snapshot, ents), uint64(id), st.Term, st.Commit)
	ents = append(ents, toAppEnts...)

	// force commit newly appended entries
	err := w.Save(raftpb.HardState{}, toAppEnts)
	if err != nil {
		plog.Fatalf("%v", err)
	}
	if len(ents) != 0 {
		st.Commit = ents[len(ents)-1].Index
	}

	plog.Printf("forcing restart of member %s in cluster %s at commit index %d", id, cid, st.Commit)
	cl := newCluster("")
	cl.SetID(cid)
	s := newRaftStorage()
	if snapshot != nil {
		s.ApplySnapshot(*snapshot)
	}
	s.SetHardState(st)
	s.Append(ents)
	c := &raft.Config{
		ID:              uint64(id),
		ElectionTick:    cfg.ElectionTicks,
		HeartbeatTick:   1,
		Storage:         s,
		MaxSizePerMsg:   maxSizePerMsg,
		MaxInflightMsgs: maxInflightMsgs,
	}
	n := raft.RestartNode(c)
	raftStatus = n.Status
	return id, cl, n, s, w
}

// restart restarts the node. restart a started node
// blocks and might affect the future stop operation.
func (n *node) restart() {
	// wait for the shutdown
	<-n.stopc
	c := &raft.Config{
		ID:              n.id,
		ElectionTick:    10,
		HeartbeatTick:   1,
		Storage:         n.storage,
		MaxSizePerMsg:   1024 * 1024,
		MaxInflightMsgs: 256,
	}
	n.Node = raft.RestartNode(c)
	n.start()
	n.iface.connect()
}

func (rc *raftNode) startRaft() {
	oldwal := wal.Exist(rc.waldir)
	rc.wal = rc.replayWAL()

	rpeers := make([]raft.Peer, len(rc.peers))
	for i := range rpeers {
		rpeers[i] = raft.Peer{ID: uint64(i + 1)}
	}
	c := &raft.Config{
		ID:              uint64(rc.id),
		ElectionTick:    10,
		HeartbeatTick:   1,
		Storage:         rc.raftStorage,
		MaxSizePerMsg:   1024 * 1024,
		MaxInflightMsgs: 256,
	}

	if oldwal {
		rc.node = raft.RestartNode(c)
	} else {
		rc.node = raft.StartNode(c, rpeers)
	}

	ss := &stats.ServerStats{}
	ss.Initialize()

	rc.transport = &rafthttp.Transport{
		ID:          types.ID(rc.id),
		ClusterID:   0x1000,
		Raft:        rc,
		ServerStats: ss,
		LeaderStats: stats.NewLeaderStats(strconv.Itoa(rc.id)),
		ErrorC:      make(chan error),
	}

	rc.transport.Start()
	for i := range rc.peers {
		if i+1 != rc.id {
			rc.transport.AddPeer(types.ID(i+1), []string{rc.peers[i]})
		}
	}

	go rc.serveRaft()
	go rc.serveChannels()
}

func restartNode(cfg *ServerConfig, snapshot *raftpb.Snapshot) (types.ID, raft.Node, *raft.MemoryStorage, *wal.WAL) {
	var walsnap walpb.Snapshot
	if snapshot != nil {
		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
	}
	w, id, cid, st, ents := readWAL(cfg.WALDir(), walsnap)
	cfg.Cluster.SetID(cid)

	log.Printf("etcdserver: restart member %s in cluster %s at commit index %d", id, cfg.Cluster.ID(), st.Commit)
	s := raft.NewMemoryStorage()
	if snapshot != nil {
		s.ApplySnapshot(*snapshot)
	}
	s.SetHardState(st)
	s.Append(ents)
	n := raft.RestartNode(uint64(id), cfg.ElectionTicks, 1, s, 0)
	return id, n, s, w
}

func restartNode(cfg *ServerConfig, index uint64, snapshot *raftpb.Snapshot) (id uint64, n raft.Node, w *wal.WAL) {
	var err error
	// restart a node from previous wal
	if w, err = wal.OpenAtIndex(cfg.WALDir(), index); err != nil {
		log.Fatal(err)
	}
	wmetadata, st, ents, err := w.ReadAll()
	if err != nil {
		log.Fatal(err)
	}

	var metadata pb.Metadata
	pbutil.MustUnmarshal(&metadata, wmetadata)
	id = metadata.NodeID
	cfg.Cluster.SetID(metadata.ClusterID)
	log.Printf("etcdserver: restart member %x in cluster %x at commit index %d", id, cfg.Cluster.ID(), st.Commit)
	n = raft.RestartNode(id, 10, 1, snapshot, st, ents)
	return
}

func restartAsStandaloneNode(cfg *ServerConfig, snapshot *raftpb.Snapshot) (types.ID, raft.Node, *raft.MemoryStorage, *wal.WAL) {
	var walsnap walpb.Snapshot
	if snapshot != nil {
		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
	}
	w, id, cid, st, ents := readWAL(cfg.WALDir(), walsnap)
	cfg.Cluster.SetID(cid)

	// discard the previously uncommitted entries
	for i, ent := range ents {
		if ent.Index > st.Commit {
			log.Printf("etcdserver: discarding %d uncommitted WAL entries ", len(ents)-i)
			ents = ents[:i]
			break
		}
	}

	// force append the configuration change entries
	toAppEnts := createConfigChangeEnts(getIDs(snapshot, ents), uint64(id), st.Term, st.Commit)
	ents = append(ents, toAppEnts...)

	// force commit newly appended entries
	for _, e := range toAppEnts {
		err := w.SaveEntry(&e)
		if err != nil {
			log.Fatalf("etcdserver: %v", err)
		}
	}
	if len(ents) != 0 {
		st.Commit = ents[len(ents)-1].Index
	}

	log.Printf("etcdserver: forcing restart of member %s in cluster %s at commit index %d", id, cfg.Cluster.ID(), st.Commit)
	s := raft.NewMemoryStorage()
	if snapshot != nil {
		s.ApplySnapshot(*snapshot)
	}
	s.SetHardState(st)
	s.Append(ents)
	n := raft.RestartNode(uint64(id), 10, 1, s)
	return id, n, s, w
}

func (n *Node) loadAndStart(ctx context.Context, forceNewCluster bool) error {
	walDir := n.walDir()
	snapDir := n.snapDir()

	if err := os.MkdirAll(snapDir, 0700); err != nil {
		return fmt.Errorf("create snapshot directory error: %v", err)
	}

	// Create a snapshotter
	n.snapshotter = snap.New(snapDir)

	if !wal.Exist(walDir) {
		return errNoWAL
	}

	// Load snapshot data
	snapshot, err := n.snapshotter.Load()
	if err != nil && err != snap.ErrNoSnapshot {
		return err
	}

	if snapshot != nil {
		// Load the snapshot data into the store
		if err := n.restoreFromSnapshot(snapshot.Data, forceNewCluster); err != nil {
			return err
		}
	}

	// Read logs to fully catch up store
	if err := n.readWAL(ctx, snapshot, forceNewCluster); err != nil {
		return err
	}

	n.Node = raft.RestartNode(n.Config)
	return nil
}

//.........这里部分代码省略.........
	raftID, err := identity.ParseNodeID(opts.ID)
	if err != nil {
		return nil, err
	}

	raftStore := raft.NewMemoryStorage()

	ctx, cancel := context.WithCancel(ctx)

	n := &Node{
		Ctx:            ctx,
		cancel:         cancel,
		cluster:        membership.NewCluster(),
		tlsCredentials: opts.TLSCredentials,
		raftStore:      raftStore,
		Address:        opts.Addr,
		Config: &raft.Config{
			ElectionTick:    cfg.ElectionTick,
			HeartbeatTick:   cfg.HeartbeatTick,
			Storage:         raftStore,
			MaxSizePerMsg:   cfg.MaxSizePerMsg,
			MaxInflightMsgs: cfg.MaxInflightMsgs,
			Logger:          cfg.Logger,
			ID:              raftID,
		},
		forceNewCluster:     opts.ForceNewCluster,
		stopCh:              make(chan struct{}),
		doneCh:              make(chan struct{}),
		StateDir:            opts.StateDir,
		joinAddr:            opts.JoinAddr,
		sendTimeout:         2 * time.Second,
		leadershipBroadcast: events.NewBroadcaster(),
	}
	n.memoryStore = store.NewMemoryStore(n)

	if opts.ClockSource == nil {
		n.ticker = clock.NewClock().NewTicker(opts.TickInterval)
	} else {
		n.ticker = opts.ClockSource.NewTicker(opts.TickInterval)
	}
	if opts.SendTimeout != 0 {
		n.sendTimeout = opts.SendTimeout
	}

	if err := n.loadAndStart(ctx, opts.ForceNewCluster); err != nil {
		n.ticker.Stop()
		return nil, err
	}

	snapshot, err := raftStore.Snapshot()
	// Snapshot never returns an error
	if err != nil {
		panic("could not get snapshot of raft store")
	}

	n.confState = snapshot.Metadata.ConfState
	n.appliedIndex = snapshot.Metadata.Index
	n.snapshotIndex = snapshot.Metadata.Index
	n.reqIDGen = idutil.NewGenerator(uint16(n.Config.ID), time.Now())
	n.wait = newWait()

	if n.startNodePeers != nil {
		if n.joinAddr != "" {
			c, err := n.ConnectToMember(n.joinAddr, 10*time.Second)
			if err != nil {
				return nil, err
			}
			defer func() {
				_ = c.Conn.Close()
			}()

			ctx, cancel := context.WithTimeout(n.Ctx, 10*time.Second)
			defer cancel()
			resp, err := c.Join(ctx, &api.JoinRequest{
				Addr: n.Address,
			})
			if err != nil {
				return nil, err
			}

			n.Node = raft.StartNode(n.Config, []raft.Peer{})

			if err := n.registerNodes(resp.Members); err != nil {
				return nil, err
			}
		} else {
			n.Node = raft.StartNode(n.Config, n.startNodePeers)
			if err := n.Campaign(n.Ctx); err != nil {
				return nil, err
			}
		}
		return n, nil
	}

	if n.joinAddr != "" {
		n.Config.Logger.Warning("ignoring request to join cluster, because raft state already exists")
	}
	n.Node = raft.RestartNode(n.Config)
	return n, nil
}