package wdclient import ( "context" "math/rand" "time" "github.com/chrislusf/seaweedfs/weed/util" "google.golang.org/grpc" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/pb" "github.com/chrislusf/seaweedfs/weed/pb/master_pb" ) type MasterClient struct { clientType string clientHost string grpcPort uint32 currentMaster string masters []string grpcDialOption grpc.DialOption vidMap } func NewMasterClient(grpcDialOption grpc.DialOption, clientType string, clientHost string, clientGrpcPort uint32, clientDataCenter string, masters []string) *MasterClient { return &MasterClient{ clientType: clientType, clientHost: clientHost, grpcPort: clientGrpcPort, masters: masters, grpcDialOption: grpcDialOption, vidMap: newVidMap(clientDataCenter), } } func (mc *MasterClient) GetMaster() string { mc.WaitUntilConnected() return mc.currentMaster } func (mc *MasterClient) WaitUntilConnected() { for mc.currentMaster == "" { time.Sleep(time.Duration(rand.Int31n(200)) * time.Millisecond) } } func (mc *MasterClient) KeepConnectedToMaster() { glog.V(1).Infof("%s masterClient bootstraps with masters %v", mc.clientType, mc.masters) for { mc.tryAllMasters() time.Sleep(time.Second) } } func (mc *MasterClient) FindLeaderFromOtherPeers(myMasterAddress string) (leader string) { for _, master := range mc.masters { if master == myMasterAddress { continue } if grpcErr := pb.WithMasterClient(master, mc.grpcDialOption, func(client master_pb.SeaweedClient) error { ctx, cancel := context.WithTimeout(context.Background(), 120*time.Millisecond) defer cancel() resp, err := client.GetMasterConfiguration(ctx, &master_pb.GetMasterConfigurationRequest{}) if err != nil { return err } leader = resp.Leader return nil }); grpcErr != nil { glog.V(0).Infof("connect to %s: %v", master, grpcErr) } if leader != "" { glog.V(0).Infof("existing leader is %s", leader) return } } glog.V(0).Infof("No existing leader found!") return } func (mc *MasterClient) tryAllMasters() { nextHintedLeader := "" for _, master := range mc.masters { nextHintedLeader = mc.tryConnectToMaster(master) for nextHintedLeader != "" { nextHintedLeader = mc.tryConnectToMaster(nextHintedLeader) } mc.currentMaster = "" mc.vidMap = newVidMap("") } } func (mc *MasterClient) tryConnectToMaster(master string) (nextHintedLeader string) { glog.V(1).Infof("%s masterClient Connecting to master %v", mc.clientType, master) gprcErr := pb.WithMasterClient(master, mc.grpcDialOption, func(client master_pb.SeaweedClient) error { ctx, cancel := context.WithCancel(context.Background()) defer cancel() stream, err := client.KeepConnected(ctx) if err != nil { glog.V(1).Infof("%s masterClient failed to keep connected to %s: %v", mc.clientType, master, err) return err } if err = stream.Send(&master_pb.KeepConnectedRequest{Name: mc.clientType, GrpcPort: mc.grpcPort}); err != nil { glog.V(0).Infof("%s masterClient failed to send to %s: %v", mc.clientType, master, err) return err } glog.V(1).Infof("%s masterClient Connected to %v", mc.clientType, master) mc.currentMaster = master for { volumeLocation, err := stream.Recv() if err != nil { glog.V(0).Infof("%s masterClient failed to receive from %s: %v", mc.clientType, master, err) return err } // maybe the leader is changed if volumeLocation.Leader != "" { glog.V(0).Infof("redirected to leader %v", volumeLocation.Leader) nextHintedLeader = volumeLocation.Leader return nil } // process new volume location loc := Location{ Url: volumeLocation.Url, PublicUrl: volumeLocation.PublicUrl, DataCenter: volumeLocation.DataCenter, } for _, newVid := range volumeLocation.NewVids { glog.V(1).Infof("%s: %s masterClient adds volume %d", mc.clientType, loc.Url, newVid) mc.addLocation(newVid, loc) } for _, deletedVid := range volumeLocation.DeletedVids { glog.V(1).Infof("%s: %s masterClient removes volume %d", mc.clientType, loc.Url, deletedVid) mc.deleteLocation(deletedVid, loc) } } }) if gprcErr != nil { glog.V(1).Infof("%s masterClient failed to connect with master %v: %v", mc.clientType, master, gprcErr) } return } func (mc *MasterClient) WithClient(fn func(client master_pb.SeaweedClient) error) error { return util.Retry("master grpc", func() error { for mc.currentMaster == "" { time.Sleep(3 * time.Second) } return pb.WithMasterClient(mc.currentMaster, mc.grpcDialOption, func(client master_pb.SeaweedClient) error { return fn(client) }) }) }