package weed_server import ( "encoding/json" "io/ioutil" "os" "path" "reflect" "sort" "time" "google.golang.org/grpc" "github.com/chrislusf/seaweedfs/weed/pb" "github.com/chrislusf/raft" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/topology" ) type RaftServer struct { peers []string // initial peers to join with raftServer raft.Server dataDir string serverAddr string topo *topology.Topology *raft.GrpcServer } func NewRaftServer(grpcDialOption grpc.DialOption, peers []string, serverAddr, dataDir string, topo *topology.Topology, pulseSeconds int) *RaftServer { s := &RaftServer{ peers: peers, serverAddr: serverAddr, dataDir: dataDir, topo: topo, } if glog.V(4) { raft.SetLogLevel(2) } raft.RegisterCommand(&topology.MaxVolumeIdCommand{}) var err error transporter := raft.NewGrpcTransporter(grpcDialOption) glog.V(0).Infof("Starting RaftServer with %v", serverAddr) // Clear old cluster configurations if peers are changed if oldPeers, changed := isPeersChanged(s.dataDir, serverAddr, s.peers); changed { glog.V(0).Infof("Peers Change: %v => %v", oldPeers, s.peers) os.RemoveAll(path.Join(s.dataDir, "conf")) os.RemoveAll(path.Join(s.dataDir, "log")) os.RemoveAll(path.Join(s.dataDir, "snapshot")) } s.raftServer, err = raft.NewServer(s.serverAddr, s.dataDir, transporter, nil, topo, "") if err != nil { glog.V(0).Infoln(err) return nil } s.raftServer.SetHeartbeatInterval(500 * time.Millisecond) s.raftServer.SetElectionTimeout(time.Duration(pulseSeconds) * 500 * time.Millisecond) s.raftServer.Start() for _, peer := range s.peers { s.raftServer.AddPeer(peer, pb.ServerToGrpcAddress(peer)) } s.GrpcServer = raft.NewGrpcServer(s.raftServer) if s.raftServer.IsLogEmpty() && isTheFirstOne(serverAddr, s.peers) { // Initialize the server by joining itself. glog.V(0).Infoln("Initializing new cluster") _, err := s.raftServer.Do(&raft.DefaultJoinCommand{ Name: s.raftServer.Name(), ConnectionString: pb.ServerToGrpcAddress(s.serverAddr), }) if err != nil { glog.V(0).Infoln(err) return nil } } glog.V(0).Infof("current cluster leader: %v", s.raftServer.Leader()) return s } func (s *RaftServer) Peers() (members []string) { peers := s.raftServer.Peers() for _, p := range peers { members = append(members, p.Name) } return } func isPeersChanged(dir string, self string, peers []string) (oldPeers []string, changed bool) { confPath := path.Join(dir, "conf") // open conf file b, err := ioutil.ReadFile(confPath) if err != nil { return oldPeers, true } conf := &raft.Config{} if err = json.Unmarshal(b, conf); err != nil { return oldPeers, true } for _, p := range conf.Peers { oldPeers = append(oldPeers, p.Name) } oldPeers = append(oldPeers, self) if len(peers) == 0 && len(oldPeers) <= 1 { return oldPeers, false } sort.Strings(peers) sort.Strings(oldPeers) return oldPeers, !reflect.DeepEqual(peers, oldPeers) } func isTheFirstOne(self string, peers []string) bool { sort.Strings(peers) if len(peers) <= 0 { return true } return self == peers[0] }