package wdclient import ( "context" "fmt" "math/rand" "time" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/pb/master_pb" "github.com/chrislusf/seaweedfs/weed/util" "google.golang.org/grpc" ) type MasterClient struct { ctx context.Context name string currentMaster string masters []string grpcDialOption grpc.DialOption vidMap } func NewMasterClient(ctx context.Context, grpcDialOption grpc.DialOption, clientName string, masters []string) *MasterClient { return &MasterClient{ ctx: ctx, name: clientName, masters: masters, grpcDialOption: grpcDialOption, vidMap: newVidMap(), } } func (mc *MasterClient) GetMaster() string { 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 bootstraps with masters %v", mc.name, mc.masters) for { mc.tryAllMasters() time.Sleep(time.Second) } } 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 Connecting to master %v", mc.name, master) gprcErr := withMasterClient(context.Background(), master, mc.grpcDialOption, func(ctx context.Context, client master_pb.SeaweedClient) error { stream, err := client.KeepConnected(ctx) if err != nil { glog.V(0).Infof("%s failed to keep connected to %s: %v", mc.name, master, err) return err } if err = stream.Send(&master_pb.KeepConnectedRequest{Name: mc.name}); err != nil { glog.V(0).Infof("%s failed to send to %s: %v", mc.name, master, err) return err } if mc.currentMaster == "" { glog.V(1).Infof("%s Connected to %v", mc.name, master) mc.currentMaster = master } for { volumeLocation, err := stream.Recv() if err != nil { glog.V(0).Infof("%s failed to receive from %s: %v", mc.name, master, err) return err } // maybe the leader is changed if volumeLocation.Leader != "" { glog.V(1).Infof("redirected to leader %v", volumeLocation.Leader) nextHintedLeader = volumeLocation.Leader return nil } // process new volume location loc := Location{ Url: volumeLocation.Url, PublicUrl: volumeLocation.PublicUrl, } for _, newVid := range volumeLocation.NewVids { glog.V(1).Infof("%s: %s adds volume %d", mc.name, loc.Url, newVid) mc.addLocation(newVid, loc) } for _, deletedVid := range volumeLocation.DeletedVids { glog.V(1).Infof("%s: %s removes volume %d", mc.name, loc.Url, deletedVid) mc.deleteLocation(deletedVid, loc) } } }) if gprcErr != nil { glog.V(0).Infof("%s failed to connect with master %v: %v", mc.name, master, gprcErr) } return } func withMasterClient(ctx context.Context, master string, grpcDialOption grpc.DialOption, fn func(ctx context.Context, client master_pb.SeaweedClient) error) error { masterGrpcAddress, parseErr := util.ParseServerToGrpcAddress(master) if parseErr != nil { return fmt.Errorf("failed to parse master grpc %v: %v", master, parseErr) } return util.WithCachedGrpcClient(ctx, func(grpcConnection *grpc.ClientConn) error { client := master_pb.NewSeaweedClient(grpcConnection) return fn(ctx, client) }, masterGrpcAddress, grpcDialOption) } func (mc *MasterClient) WithClient(ctx context.Context, fn func(client master_pb.SeaweedClient) error) error { return withMasterClient(ctx, mc.currentMaster, mc.grpcDialOption, func(ctx context.Context, client master_pb.SeaweedClient) error { return fn(client) }) }