seaweedfs/weed/wdclient/masterclient.go
2019-12-11 21:40:33 -08:00

140 lines
3.8 KiB
Go

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
}
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(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,
}
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)
})
}