Merge branch 'master' of https://github.com/bingoohuang/seaweedfs

16 files changed, 1385 insertions, 0 deletions

diff --git a/weed/messaging/broker/broker_append.go b/weed/messaging/broker/broker_append.go
new file mode 100644
index 000000000..8e5b56fd0
--- /dev/null
+++ b/weed/messaging/broker/broker_append.go
@@ -0,0 +1,113 @@
+package broker
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/operation"
+	"github.com/chrislusf/seaweedfs/weed/pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+	"github.com/chrislusf/seaweedfs/weed/security"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+func (broker *MessageBroker) appendToFile(targetFile string, topicConfig *messaging_pb.TopicConfiguration, data []byte) error {
+
+	assignResult, uploadResult, err2 := broker.assignAndUpload(topicConfig, data)
+	if err2 != nil {
+		return err2
+	}
+
+	dir, name := util.FullPath(targetFile).DirAndName()
+
+	// append the chunk
+	if err := broker.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+
+		request := &filer_pb.AppendToEntryRequest{
+			Directory: dir,
+			EntryName: name,
+			Chunks:    []*filer_pb.FileChunk{uploadResult.ToPbFileChunk(assignResult.Fid, 0)},
+		}
+
+		_, err := client.AppendToEntry(context.Background(), request)
+		if err != nil {
+			glog.V(0).Infof("append to file %v: %v", request, err)
+			return err
+		}
+
+		return nil
+	}); err != nil {
+		return fmt.Errorf("append to file %v: %v", targetFile, err)
+	}
+
+	return nil
+}
+
+func (broker *MessageBroker) assignAndUpload(topicConfig *messaging_pb.TopicConfiguration, data []byte) (*operation.AssignResult, *operation.UploadResult, error) {
+
+	var assignResult = &operation.AssignResult{}
+
+	// assign a volume location
+	if err := broker.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+
+		request := &filer_pb.AssignVolumeRequest{
+			Count:       1,
+			Replication: topicConfig.Replication,
+			Collection:  topicConfig.Collection,
+		}
+
+		resp, err := client.AssignVolume(context.Background(), request)
+		if err != nil {
+			glog.V(0).Infof("assign volume failure %v: %v", request, err)
+			return err
+		}
+		if resp.Error != "" {
+			return fmt.Errorf("assign volume failure %v: %v", request, resp.Error)
+		}
+
+		assignResult.Auth = security.EncodedJwt(resp.Auth)
+		assignResult.Fid = resp.FileId
+		assignResult.Url = resp.Url
+		assignResult.PublicUrl = resp.PublicUrl
+		assignResult.Count = uint64(resp.Count)
+
+		return nil
+	}); err != nil {
+		return nil, nil, err
+	}
+
+	// upload data
+	targetUrl := fmt.Sprintf("http://%s/%s", assignResult.Url, assignResult.Fid)
+	uploadResult, err := operation.UploadData(targetUrl, "", broker.option.Cipher, data, false, "", nil, assignResult.Auth)
+	if err != nil {
+		return nil, nil, fmt.Errorf("upload data %s: %v", targetUrl, err)
+	}
+	// println("uploaded to", targetUrl)
+	return assignResult, uploadResult, nil
+}
+
+var _ = filer_pb.FilerClient(&MessageBroker{})
+
+func (broker *MessageBroker) WithFilerClient(fn func(filer_pb.SeaweedFilerClient) error) (err error) {
+
+	for _, filer := range broker.option.Filers {
+		if err = pb.WithFilerClient(filer, broker.grpcDialOption, fn); err != nil {
+			if err == io.EOF {
+				return
+			}
+			glog.V(0).Infof("fail to connect to %s: %v", filer, err)
+		} else {
+			break
+		}
+	}
+
+	return
+
+}
+
+func (broker *MessageBroker) AdjustedUrl(location *filer_pb.Location) string {
+	return location.Url
+}
diff --git a/weed/messaging/broker/broker_grpc_server.go b/weed/messaging/broker/broker_grpc_server.go
new file mode 100644
index 000000000..ba141fdd0
--- /dev/null
+++ b/weed/messaging/broker/broker_grpc_server.go
@@ -0,0 +1,37 @@
+package broker
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+func (broker *MessageBroker) ConfigureTopic(c context.Context, request *messaging_pb.ConfigureTopicRequest) (*messaging_pb.ConfigureTopicResponse, error) {
+	panic("implement me")
+}
+
+func (broker *MessageBroker) DeleteTopic(c context.Context, request *messaging_pb.DeleteTopicRequest) (*messaging_pb.DeleteTopicResponse, error) {
+	resp := &messaging_pb.DeleteTopicResponse{}
+	dir, entry := genTopicDirEntry(request.Namespace, request.Topic)
+	if exists, err := filer_pb.Exists(broker, dir, entry, true); err != nil {
+		return nil, err
+	} else if exists {
+		err = filer_pb.Remove(broker, dir, entry, true, true, true, false, nil)
+	}
+	return resp, nil
+}
+
+func (broker *MessageBroker) GetTopicConfiguration(c context.Context, request *messaging_pb.GetTopicConfigurationRequest) (*messaging_pb.GetTopicConfigurationResponse, error) {
+	panic("implement me")
+}
+
+func genTopicDir(namespace, topic string) string {
+	return fmt.Sprintf("%s/%s/%s", filer.TopicsDir, namespace, topic)
+}
+
+func genTopicDirEntry(namespace, topic string) (dir, entry string) {
+	return fmt.Sprintf("%s/%s", filer.TopicsDir, namespace), topic
+}
diff --git a/weed/messaging/broker/broker_grpc_server_discovery.go b/weed/messaging/broker/broker_grpc_server_discovery.go
new file mode 100644
index 000000000..3c14f3220
--- /dev/null
+++ b/weed/messaging/broker/broker_grpc_server_discovery.go
@@ -0,0 +1,116 @@
+package broker
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+/*
+Topic discovery:
+
+When pub or sub connects, it ask for the whole broker list, and run consistent hashing to find the broker.
+
+The broker will check peers whether it is already hosted by some other broker, if that broker is alive and acknowledged alive, redirect to it.
+Otherwise, just host the topic.
+
+So, if the pub or sub connects around the same time, they would connect to the same broker. Everyone is happy.
+If one of the pub or sub connects very late, and the system topo changed quite a bit with new servers added or old servers died, checking peers will help.
+
+*/
+
+func (broker *MessageBroker) FindBroker(c context.Context, request *messaging_pb.FindBrokerRequest) (*messaging_pb.FindBrokerResponse, error) {
+
+	t := &messaging_pb.FindBrokerResponse{}
+	var peers []string
+
+	targetTopicPartition := fmt.Sprintf(TopicPartitionFmt, request.Namespace, request.Topic, request.Parition)
+
+	for _, filer := range broker.option.Filers {
+		err := broker.withFilerClient(filer, func(client filer_pb.SeaweedFilerClient) error {
+			resp, err := client.LocateBroker(context.Background(), &filer_pb.LocateBrokerRequest{
+				Resource: targetTopicPartition,
+			})
+			if err != nil {
+				return err
+			}
+			if resp.Found && len(resp.Resources) > 0 {
+				t.Broker = resp.Resources[0].GrpcAddresses
+				return nil
+			}
+			for _, b := range resp.Resources {
+				peers = append(peers, b.GrpcAddresses)
+			}
+			return nil
+		})
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	t.Broker = PickMember(peers, []byte(targetTopicPartition))
+
+	return t, nil
+
+}
+
+func (broker *MessageBroker) checkFilers() {
+
+	// contact a filer about masters
+	var masters []string
+	found := false
+	for !found {
+		for _, filer := range broker.option.Filers {
+			err := broker.withFilerClient(filer, func(client filer_pb.SeaweedFilerClient) error {
+				resp, err := client.GetFilerConfiguration(context.Background(), &filer_pb.GetFilerConfigurationRequest{})
+				if err != nil {
+					return err
+				}
+				masters = append(masters, resp.Masters...)
+				return nil
+			})
+			if err == nil {
+				found = true
+				break
+			}
+			glog.V(0).Infof("failed to read masters from %+v: %v", broker.option.Filers, err)
+			time.Sleep(time.Second)
+		}
+	}
+	glog.V(0).Infof("received master list: %s", masters)
+
+	// contact each masters for filers
+	var filers []string
+	found = false
+	for !found {
+		for _, master := range masters {
+			err := broker.withMasterClient(master, func(client master_pb.SeaweedClient) error {
+				resp, err := client.ListMasterClients(context.Background(), &master_pb.ListMasterClientsRequest{
+					ClientType: "filer",
+				})
+				if err != nil {
+					return err
+				}
+
+				filers = append(filers, resp.GrpcAddresses...)
+
+				return nil
+			})
+			if err == nil {
+				found = true
+				break
+			}
+			glog.V(0).Infof("failed to list filers: %v", err)
+			time.Sleep(time.Second)
+		}
+	}
+	glog.V(0).Infof("received filer list: %s", filers)
+
+	broker.option.Filers = filers
+
+}
diff --git a/weed/messaging/broker/broker_grpc_server_publish.go b/weed/messaging/broker/broker_grpc_server_publish.go
new file mode 100644
index 000000000..6e6b723d1
--- /dev/null
+++ b/weed/messaging/broker/broker_grpc_server_publish.go
@@ -0,0 +1,112 @@
+package broker
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+func (broker *MessageBroker) Publish(stream messaging_pb.SeaweedMessaging_PublishServer) error {
+
+	// process initial request
+	in, err := stream.Recv()
+	if err == io.EOF {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+
+	// TODO look it up
+	topicConfig := &messaging_pb.TopicConfiguration{
+		// IsTransient: true,
+	}
+
+	// send init response
+	initResponse := &messaging_pb.PublishResponse{
+		Config:   nil,
+		Redirect: nil,
+	}
+	err = stream.Send(initResponse)
+	if err != nil {
+		return err
+	}
+	if initResponse.Redirect != nil {
+		return nil
+	}
+
+	// get lock
+	tp := TopicPartition{
+		Namespace: in.Init.Namespace,
+		Topic:     in.Init.Topic,
+		Partition: in.Init.Partition,
+	}
+
+	tpDir := fmt.Sprintf("%s/%s/%s", filer.TopicsDir, tp.Namespace, tp.Topic)
+	md5File := fmt.Sprintf("p%02d.md5", tp.Partition)
+	// println("chan data stored under", tpDir, "as", md5File)
+
+	if exists, err := filer_pb.Exists(broker, tpDir, md5File, false); err == nil && exists {
+		return fmt.Errorf("channel is already closed")
+	}
+
+	tl := broker.topicManager.RequestLock(tp, topicConfig, true)
+	defer broker.topicManager.ReleaseLock(tp, true)
+
+	md5hash := md5.New()
+	// process each message
+	for {
+		// println("recv")
+		in, err := stream.Recv()
+		// glog.V(0).Infof("recieved %v err: %v", in, err)
+		if err == io.EOF {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+
+		if in.Data == nil {
+			continue
+		}
+
+		// fmt.Printf("received: %d : %s\n", len(in.Data.Value), string(in.Data.Value))
+
+		data, err := proto.Marshal(in.Data)
+		if err != nil {
+			glog.Errorf("marshall error: %v\n", err)
+			continue
+		}
+
+		tl.logBuffer.AddToBuffer(in.Data.Key, data, in.Data.EventTimeNs)
+
+		if in.Data.IsClose {
+			// println("server received closing")
+			break
+		}
+
+		md5hash.Write(in.Data.Value)
+
+	}
+
+	if err := broker.appendToFile(tpDir+"/"+md5File, topicConfig, md5hash.Sum(nil)); err != nil {
+		glog.V(0).Infof("err writing %s: %v", md5File, err)
+	}
+
+	// fmt.Printf("received md5 %X\n", md5hash.Sum(nil))
+
+	// send the close ack
+	// println("server send ack closing")
+	if err := stream.Send(&messaging_pb.PublishResponse{IsClosed: true}); err != nil {
+		glog.V(0).Infof("err sending close response: %v", err)
+	}
+	return nil
+
+}
diff --git a/weed/messaging/broker/broker_grpc_server_subscribe.go b/weed/messaging/broker/broker_grpc_server_subscribe.go
new file mode 100644
index 000000000..3021473e5
--- /dev/null
+++ b/weed/messaging/broker/broker_grpc_server_subscribe.go
@@ -0,0 +1,177 @@
+package broker
+
+import (
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/util/log_buffer"
+	"io"
+	"strings"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+func (broker *MessageBroker) Subscribe(stream messaging_pb.SeaweedMessaging_SubscribeServer) error {
+
+	// process initial request
+	in, err := stream.Recv()
+	if err == io.EOF {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+
+	var processedTsNs int64
+	var messageCount int64
+	subscriberId := in.Init.SubscriberId
+
+	// TODO look it up
+	topicConfig := &messaging_pb.TopicConfiguration{
+		// IsTransient: true,
+	}
+
+	// get lock
+	tp := TopicPartition{
+		Namespace: in.Init.Namespace,
+		Topic:     in.Init.Topic,
+		Partition: in.Init.Partition,
+	}
+	fmt.Printf("+ subscriber %s for %s\n", subscriberId, tp.String())
+	defer func() {
+		fmt.Printf("- subscriber %s for %s %d messages last %v\n", subscriberId, tp.String(), messageCount, time.Unix(0, processedTsNs))
+	}()
+
+	lock := broker.topicManager.RequestLock(tp, topicConfig, false)
+	defer broker.topicManager.ReleaseLock(tp, false)
+
+	isConnected := true
+	go func() {
+		for isConnected {
+			if _, err := stream.Recv(); err != nil {
+				// println("disconnecting connection to", subscriberId, tp.String())
+				isConnected = false
+				lock.cond.Signal()
+			}
+		}
+	}()
+
+	lastReadTime := time.Now()
+	switch in.Init.StartPosition {
+	case messaging_pb.SubscriberMessage_InitMessage_TIMESTAMP:
+		lastReadTime = time.Unix(0, in.Init.TimestampNs)
+	case messaging_pb.SubscriberMessage_InitMessage_LATEST:
+	case messaging_pb.SubscriberMessage_InitMessage_EARLIEST:
+		lastReadTime = time.Unix(0, 0)
+	}
+
+	// how to process each message
+	// an error returned will end the subscription
+	eachMessageFn := func(m *messaging_pb.Message) error {
+		err := stream.Send(&messaging_pb.BrokerMessage{
+			Data: m,
+		})
+		if err != nil {
+			glog.V(0).Infof("=> subscriber %v: %+v", subscriberId, err)
+		}
+		return err
+	}
+
+	eachLogEntryFn := func(logEntry *filer_pb.LogEntry) error {
+		m := &messaging_pb.Message{}
+		if err = proto.Unmarshal(logEntry.Data, m); err != nil {
+			glog.Errorf("unexpected unmarshal messaging_pb.Message: %v", err)
+			return err
+		}
+		// fmt.Printf("sending : %d bytes ts %d\n", len(m.Value), logEntry.TsNs)
+		if err = eachMessageFn(m); err != nil {
+			glog.Errorf("sending %d bytes to %s: %s", len(m.Value), subscriberId, err)
+			return err
+		}
+		if m.IsClose {
+			// println("processed EOF")
+			return io.EOF
+		}
+		processedTsNs = logEntry.TsNs
+		messageCount++
+		return nil
+	}
+
+	// fmt.Printf("subscriber %s read %d on disk log %v\n", subscriberId, messageCount, lastReadTime)
+
+	for {
+
+		if err = broker.readPersistedLogBuffer(&tp, lastReadTime, eachLogEntryFn); err != nil {
+			if err != io.EOF {
+				// println("stopping from persisted logs", err.Error())
+				return err
+			}
+		}
+
+		if processedTsNs != 0 {
+			lastReadTime = time.Unix(0, processedTsNs)
+		}
+
+		lastReadTime, err = lock.logBuffer.LoopProcessLogData(lastReadTime, func() bool {
+			lock.Mutex.Lock()
+			lock.cond.Wait()
+			lock.Mutex.Unlock()
+			return isConnected
+		}, eachLogEntryFn)
+		if err != nil {
+			if err == log_buffer.ResumeFromDiskError {
+				continue
+			}
+			glog.Errorf("processed to %v: %v", lastReadTime, err)
+			time.Sleep(3127 * time.Millisecond)
+			if err != log_buffer.ResumeError {
+				break
+			}
+		}
+	}
+
+	return err
+
+}
+
+func (broker *MessageBroker) readPersistedLogBuffer(tp *TopicPartition, startTime time.Time, eachLogEntryFn func(logEntry *filer_pb.LogEntry) error) (err error) {
+	startTime = startTime.UTC()
+	startDate := fmt.Sprintf("%04d-%02d-%02d", startTime.Year(), startTime.Month(), startTime.Day())
+	startHourMinute := fmt.Sprintf("%02d-%02d.segment", startTime.Hour(), startTime.Minute())
+
+	sizeBuf := make([]byte, 4)
+	startTsNs := startTime.UnixNano()
+
+	topicDir := genTopicDir(tp.Namespace, tp.Topic)
+	partitionSuffix := fmt.Sprintf(".part%02d", tp.Partition)
+
+	return filer_pb.List(broker, topicDir, "", func(dayEntry *filer_pb.Entry, isLast bool) error {
+		dayDir := fmt.Sprintf("%s/%s", topicDir, dayEntry.Name)
+		return filer_pb.List(broker, dayDir, "", func(hourMinuteEntry *filer_pb.Entry, isLast bool) error {
+			if dayEntry.Name == startDate {
+				if strings.Compare(hourMinuteEntry.Name, startHourMinute) < 0 {
+					return nil
+				}
+			}
+			if !strings.HasSuffix(hourMinuteEntry.Name, partitionSuffix) {
+				return nil
+			}
+			// println("partition", tp.Partition, "processing", dayDir, "/", hourMinuteEntry.Name)
+			chunkedFileReader := filer.NewChunkStreamReader(broker, hourMinuteEntry.Chunks)
+			defer chunkedFileReader.Close()
+			if _, err := filer.ReadEachLogEntry(chunkedFileReader, sizeBuf, startTsNs, eachLogEntryFn); err != nil {
+				chunkedFileReader.Close()
+				if err == io.EOF {
+					return err
+				}
+				return fmt.Errorf("reading %s/%s: %v", dayDir, hourMinuteEntry.Name, err)
+			}
+			return nil
+		}, "", false, 24*60)
+	}, startDate, true, 366)
+
+}
diff --git a/weed/messaging/broker/broker_server.go b/weed/messaging/broker/broker_server.go
new file mode 100644
index 000000000..06162471c
--- /dev/null
+++ b/weed/messaging/broker/broker_server.go
@@ -0,0 +1,114 @@
+package broker
+
+import (
+	"context"
+	"time"
+
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
+)
+
+type MessageBrokerOption struct {
+	Filers             []string
+	DefaultReplication string
+	MaxMB              int
+	Ip                 string
+	Port               int
+	Cipher             bool
+}
+
+type MessageBroker struct {
+	option         *MessageBrokerOption
+	grpcDialOption grpc.DialOption
+	topicManager   *TopicManager
+}
+
+func NewMessageBroker(option *MessageBrokerOption, grpcDialOption grpc.DialOption) (messageBroker *MessageBroker, err error) {
+
+	messageBroker = &MessageBroker{
+		option:         option,
+		grpcDialOption: grpcDialOption,
+	}
+
+	messageBroker.topicManager = NewTopicManager(messageBroker)
+
+	messageBroker.checkFilers()
+
+	go messageBroker.keepConnectedToOneFiler()
+
+	return messageBroker, nil
+}
+
+func (broker *MessageBroker) keepConnectedToOneFiler() {
+
+	for {
+		for _, filer := range broker.option.Filers {
+			broker.withFilerClient(filer, func(client filer_pb.SeaweedFilerClient) error {
+				ctx, cancel := context.WithCancel(context.Background())
+				defer cancel()
+				stream, err := client.KeepConnected(ctx)
+				if err != nil {
+					glog.V(0).Infof("%s:%d failed to keep connected to %s: %v", broker.option.Ip, broker.option.Port, filer, err)
+					return err
+				}
+
+				initRequest := &filer_pb.KeepConnectedRequest{
+					Name:     broker.option.Ip,
+					GrpcPort: uint32(broker.option.Port),
+				}
+				for _, tp := range broker.topicManager.ListTopicPartitions() {
+					initRequest.Resources = append(initRequest.Resources, tp.String())
+				}
+				if err := stream.Send(&filer_pb.KeepConnectedRequest{
+					Name:     broker.option.Ip,
+					GrpcPort: uint32(broker.option.Port),
+				}); err != nil {
+					glog.V(0).Infof("broker %s:%d failed to init at %s: %v", broker.option.Ip, broker.option.Port, filer, err)
+					return err
+				}
+
+				// TODO send events of adding/removing topics
+
+				glog.V(0).Infof("conntected with filer: %v", filer)
+				for {
+					if err := stream.Send(&filer_pb.KeepConnectedRequest{
+						Name:     broker.option.Ip,
+						GrpcPort: uint32(broker.option.Port),
+					}); err != nil {
+						glog.V(0).Infof("%s:%d failed to sendto %s: %v", broker.option.Ip, broker.option.Port, filer, err)
+						return err
+					}
+					// println("send heartbeat")
+					if _, err := stream.Recv(); err != nil {
+						glog.V(0).Infof("%s:%d failed to receive from %s: %v", broker.option.Ip, broker.option.Port, filer, err)
+						return err
+					}
+					// println("received reply")
+					time.Sleep(11 * time.Second)
+					// println("woke up")
+				}
+				return nil
+			})
+			time.Sleep(3 * time.Second)
+		}
+	}
+
+}
+
+func (broker *MessageBroker) withFilerClient(filer string, fn func(filer_pb.SeaweedFilerClient) error) error {
+
+	return pb.WithFilerClient(filer, broker.grpcDialOption, fn)
+
+}
+
+func (broker *MessageBroker) withMasterClient(master string, fn func(client master_pb.SeaweedClient) error) error {
+
+	return pb.WithMasterClient(master, broker.grpcDialOption, func(client master_pb.SeaweedClient) error {
+		return fn(client)
+	})
+
+}
diff --git a/weed/messaging/broker/consistent_distribution.go b/weed/messaging/broker/consistent_distribution.go
new file mode 100644
index 000000000..465a2a8f2
--- /dev/null
+++ b/weed/messaging/broker/consistent_distribution.go
@@ -0,0 +1,38 @@
+package broker
+
+import (
+	"github.com/buraksezer/consistent"
+	"github.com/cespare/xxhash"
+)
+
+type Member string
+
+func (m Member) String() string {
+	return string(m)
+}
+
+type hasher struct{}
+
+func (h hasher) Sum64(data []byte) uint64 {
+	return xxhash.Sum64(data)
+}
+
+func PickMember(members []string, key []byte) string {
+	cfg := consistent.Config{
+		PartitionCount:    9791,
+		ReplicationFactor: 2,
+		Load:              1.25,
+		Hasher:            hasher{},
+	}
+
+	cmembers := []consistent.Member{}
+	for _, m := range members {
+		cmembers = append(cmembers, Member(m))
+	}
+
+	c := consistent.New(cmembers, cfg)
+
+	m := c.LocateKey(key)
+
+	return m.String()
+}
diff --git a/weed/messaging/broker/consistent_distribution_test.go b/weed/messaging/broker/consistent_distribution_test.go
new file mode 100644
index 000000000..f58fe4e0e
--- /dev/null
+++ b/weed/messaging/broker/consistent_distribution_test.go
@@ -0,0 +1,32 @@
+package broker
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestPickMember(t *testing.T) {
+
+	servers := []string{
+		"s1:port",
+		"s2:port",
+		"s3:port",
+		"s5:port",
+		"s4:port",
+	}
+
+	total := 1000
+
+	distribution := make(map[string]int)
+	for i := 0; i < total; i++ {
+		tp := fmt.Sprintf("tp:%2d", i)
+		m := PickMember(servers, []byte(tp))
+		// println(tp, "=>", m)
+		distribution[m]++
+	}
+
+	for member, count := range distribution {
+		fmt.Printf("member: %s, key count: %d load=%.2f\n", member, count, float64(count*100)/float64(total/len(servers)))
+	}
+
+}
diff --git a/weed/messaging/broker/topic_manager.go b/weed/messaging/broker/topic_manager.go
new file mode 100644
index 000000000..edddca813
--- /dev/null
+++ b/weed/messaging/broker/topic_manager.go
@@ -0,0 +1,124 @@
+package broker
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+	"github.com/chrislusf/seaweedfs/weed/util/log_buffer"
+)
+
+type TopicPartition struct {
+	Namespace string
+	Topic     string
+	Partition int32
+}
+
+const (
+	TopicPartitionFmt = "%s/%s_%02d"
+)
+
+func (tp *TopicPartition) String() string {
+	return fmt.Sprintf(TopicPartitionFmt, tp.Namespace, tp.Topic, tp.Partition)
+}
+
+type TopicControl struct {
+	sync.Mutex
+	cond            *sync.Cond
+	subscriberCount int
+	publisherCount  int
+	logBuffer       *log_buffer.LogBuffer
+}
+
+type TopicManager struct {
+	sync.Mutex
+	topicControls map[TopicPartition]*TopicControl
+	broker        *MessageBroker
+}
+
+func NewTopicManager(messageBroker *MessageBroker) *TopicManager {
+	return &TopicManager{
+		topicControls: make(map[TopicPartition]*TopicControl),
+		broker:        messageBroker,
+	}
+}
+
+func (tm *TopicManager) buildLogBuffer(tl *TopicControl, tp TopicPartition, topicConfig *messaging_pb.TopicConfiguration) *log_buffer.LogBuffer {
+
+	flushFn := func(startTime, stopTime time.Time, buf []byte) {
+
+		if topicConfig.IsTransient {
+			// return
+		}
+
+		// fmt.Printf("flushing with topic config %+v\n", topicConfig)
+
+		startTime, stopTime = startTime.UTC(), stopTime.UTC()
+		targetFile := fmt.Sprintf(
+			"%s/%s/%s/%04d-%02d-%02d/%02d-%02d.part%02d",
+			filer.TopicsDir, tp.Namespace, tp.Topic,
+			startTime.Year(), startTime.Month(), startTime.Day(), startTime.Hour(), startTime.Minute(),
+			tp.Partition,
+		)
+
+		if err := tm.broker.appendToFile(targetFile, topicConfig, buf); err != nil {
+			glog.V(0).Infof("log write failed %s: %v", targetFile, err)
+		}
+	}
+	logBuffer := log_buffer.NewLogBuffer(time.Minute, flushFn, func() {
+		tl.cond.Broadcast()
+	})
+
+	return logBuffer
+}
+
+func (tm *TopicManager) RequestLock(partition TopicPartition, topicConfig *messaging_pb.TopicConfiguration, isPublisher bool) *TopicControl {
+	tm.Lock()
+	defer tm.Unlock()
+
+	tc, found := tm.topicControls[partition]
+	if !found {
+		tc = &TopicControl{}
+		tc.cond = sync.NewCond(&tc.Mutex)
+		tm.topicControls[partition] = tc
+		tc.logBuffer = tm.buildLogBuffer(tc, partition, topicConfig)
+	}
+	if isPublisher {
+		tc.publisherCount++
+	} else {
+		tc.subscriberCount++
+	}
+	return tc
+}
+
+func (tm *TopicManager) ReleaseLock(partition TopicPartition, isPublisher bool) {
+	tm.Lock()
+	defer tm.Unlock()
+
+	lock, found := tm.topicControls[partition]
+	if !found {
+		return
+	}
+	if isPublisher {
+		lock.publisherCount--
+	} else {
+		lock.subscriberCount--
+	}
+	if lock.subscriberCount <= 0 && lock.publisherCount <= 0 {
+		delete(tm.topicControls, partition)
+		lock.logBuffer.Shutdown()
+	}
+}
+
+func (tm *TopicManager) ListTopicPartitions() (tps []TopicPartition) {
+	tm.Lock()
+	defer tm.Unlock()
+
+	for k := range tm.topicControls {
+		tps = append(tps, k)
+	}
+	return
+}
diff --git a/weed/messaging/msgclient/chan_config.go b/weed/messaging/msgclient/chan_config.go
new file mode 100644
index 000000000..a75678815
--- /dev/null
+++ b/weed/messaging/msgclient/chan_config.go
@@ -0,0 +1,5 @@
+package msgclient
+
+func (mc *MessagingClient) DeleteChannel(chanName string) error {
+	return mc.DeleteTopic("chan", chanName)
+}
diff --git a/weed/messaging/msgclient/chan_pub.go b/weed/messaging/msgclient/chan_pub.go
new file mode 100644
index 000000000..9bc88f7c0
--- /dev/null
+++ b/weed/messaging/msgclient/chan_pub.go
@@ -0,0 +1,76 @@
+package msgclient
+
+import (
+	"crypto/md5"
+	"hash"
+	"io"
+	"log"
+
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+type PubChannel struct {
+	client         messaging_pb.SeaweedMessaging_PublishClient
+	grpcConnection *grpc.ClientConn
+	md5hash        hash.Hash
+}
+
+func (mc *MessagingClient) NewPubChannel(chanName string) (*PubChannel, error) {
+	tp := broker.TopicPartition{
+		Namespace: "chan",
+		Topic:     chanName,
+		Partition: 0,
+	}
+	grpcConnection, err := mc.findBroker(tp)
+	if err != nil {
+		return nil, err
+	}
+	pc, err := setupPublisherClient(grpcConnection, tp)
+	if err != nil {
+		return nil, err
+	}
+	return &PubChannel{
+		client:         pc,
+		grpcConnection: grpcConnection,
+		md5hash:        md5.New(),
+	}, nil
+}
+
+func (pc *PubChannel) Publish(m []byte) error {
+	err := pc.client.Send(&messaging_pb.PublishRequest{
+		Data: &messaging_pb.Message{
+			Value: m,
+		},
+	})
+	if err == nil {
+		pc.md5hash.Write(m)
+	}
+	return err
+}
+func (pc *PubChannel) Close() error {
+
+	// println("send closing")
+	if err := pc.client.Send(&messaging_pb.PublishRequest{
+		Data: &messaging_pb.Message{
+			IsClose: true,
+		},
+	}); err != nil {
+		log.Printf("err send close: %v", err)
+	}
+	// println("receive closing")
+	if _, err := pc.client.Recv(); err != nil && err != io.EOF {
+		log.Printf("err receive close: %v", err)
+	}
+	// println("close connection")
+	if err := pc.grpcConnection.Close(); err != nil {
+		log.Printf("err connection close: %v", err)
+	}
+	return nil
+}
+
+func (pc *PubChannel) Md5() []byte {
+	return pc.md5hash.Sum(nil)
+}
diff --git a/weed/messaging/msgclient/chan_sub.go b/weed/messaging/msgclient/chan_sub.go
new file mode 100644
index 000000000..213ff4666
--- /dev/null
+++ b/weed/messaging/msgclient/chan_sub.go
@@ -0,0 +1,85 @@
+package msgclient
+
+import (
+	"context"
+	"crypto/md5"
+	"hash"
+	"io"
+	"log"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+type SubChannel struct {
+	ch      chan []byte
+	stream  messaging_pb.SeaweedMessaging_SubscribeClient
+	md5hash hash.Hash
+	cancel  context.CancelFunc
+}
+
+func (mc *MessagingClient) NewSubChannel(subscriberId, chanName string) (*SubChannel, error) {
+	tp := broker.TopicPartition{
+		Namespace: "chan",
+		Topic:     chanName,
+		Partition: 0,
+	}
+	grpcConnection, err := mc.findBroker(tp)
+	if err != nil {
+		return nil, err
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	sc, err := setupSubscriberClient(ctx, grpcConnection, tp, subscriberId, time.Unix(0, 0))
+	if err != nil {
+		return nil, err
+	}
+
+	t := &SubChannel{
+		ch:      make(chan []byte),
+		stream:  sc,
+		md5hash: md5.New(),
+		cancel:  cancel,
+	}
+
+	go func() {
+		for {
+			resp, subErr := t.stream.Recv()
+			if subErr == io.EOF {
+				return
+			}
+			if subErr != nil {
+				log.Printf("fail to receive from netchan %s: %v", chanName, subErr)
+				return
+			}
+			if resp.Data == nil {
+				// this could be heartbeat from broker
+				continue
+			}
+			if resp.Data.IsClose {
+				t.stream.Send(&messaging_pb.SubscriberMessage{
+					IsClose: true,
+				})
+				close(t.ch)
+				cancel()
+				return
+			}
+			t.ch <- resp.Data.Value
+			t.md5hash.Write(resp.Data.Value)
+		}
+	}()
+
+	return t, nil
+}
+
+func (sc *SubChannel) Channel() chan []byte {
+	return sc.ch
+}
+
+func (sc *SubChannel) Md5() []byte {
+	return sc.md5hash.Sum(nil)
+}
+
+func (sc *SubChannel) Cancel() {
+	sc.cancel()
+}
diff --git a/weed/messaging/msgclient/client.go b/weed/messaging/msgclient/client.go
new file mode 100644
index 000000000..4d7ef2b8e
--- /dev/null
+++ b/weed/messaging/msgclient/client.go
@@ -0,0 +1,55 @@
+package msgclient
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+	"github.com/chrislusf/seaweedfs/weed/security"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+type MessagingClient struct {
+	bootstrapBrokers []string
+	grpcConnections  map[broker.TopicPartition]*grpc.ClientConn
+	grpcDialOption   grpc.DialOption
+}
+
+func NewMessagingClient(bootstrapBrokers ...string) *MessagingClient {
+	return &MessagingClient{
+		bootstrapBrokers: bootstrapBrokers,
+		grpcConnections:  make(map[broker.TopicPartition]*grpc.ClientConn),
+		grpcDialOption:   security.LoadClientTLS(util.GetViper(), "grpc.msg_client"),
+	}
+}
+
+func (mc *MessagingClient) findBroker(tp broker.TopicPartition) (*grpc.ClientConn, error) {
+
+	for _, broker := range mc.bootstrapBrokers {
+		grpcConnection, err := pb.GrpcDial(context.Background(), broker, mc.grpcDialOption)
+		if err != nil {
+			log.Printf("dial broker %s: %v", broker, err)
+			continue
+		}
+		defer grpcConnection.Close()
+
+		resp, err := messaging_pb.NewSeaweedMessagingClient(grpcConnection).FindBroker(context.Background(),
+			&messaging_pb.FindBrokerRequest{
+				Namespace: tp.Namespace,
+				Topic:     tp.Topic,
+				Parition:  tp.Partition,
+			})
+		if err != nil {
+			return nil, err
+		}
+
+		targetBroker := resp.Broker
+		return pb.GrpcDial(context.Background(), targetBroker, mc.grpcDialOption)
+	}
+	return nil, fmt.Errorf("no broker found for %+v", tp)
+}
diff --git a/weed/messaging/msgclient/config.go b/weed/messaging/msgclient/config.go
new file mode 100644
index 000000000..2b9eba1a8
--- /dev/null
+++ b/weed/messaging/msgclient/config.go
@@ -0,0 +1,63 @@
+package msgclient
+
+import (
+	"context"
+	"log"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+func (mc *MessagingClient) configureTopic(tp broker.TopicPartition) error {
+
+	return mc.withAnyBroker(func(client messaging_pb.SeaweedMessagingClient) error {
+		_, err := client.ConfigureTopic(context.Background(),
+			&messaging_pb.ConfigureTopicRequest{
+				Namespace: tp.Namespace,
+				Topic:     tp.Topic,
+				Configuration: &messaging_pb.TopicConfiguration{
+					PartitionCount: 0,
+					Collection:     "",
+					Replication:    "",
+					IsTransient:    false,
+					Partitoning:    0,
+				},
+			})
+		return err
+	})
+
+}
+
+func (mc *MessagingClient) DeleteTopic(namespace, topic string) error {
+
+	return mc.withAnyBroker(func(client messaging_pb.SeaweedMessagingClient) error {
+		_, err := client.DeleteTopic(context.Background(),
+			&messaging_pb.DeleteTopicRequest{
+				Namespace: namespace,
+				Topic:     topic,
+			})
+		return err
+	})
+}
+
+func (mc *MessagingClient) withAnyBroker(fn func(client messaging_pb.SeaweedMessagingClient) error) error {
+
+	var lastErr error
+	for _, broker := range mc.bootstrapBrokers {
+		grpcConnection, err := pb.GrpcDial(context.Background(), broker, mc.grpcDialOption)
+		if err != nil {
+			log.Printf("dial broker %s: %v", broker, err)
+			continue
+		}
+		defer grpcConnection.Close()
+
+		err = fn(messaging_pb.NewSeaweedMessagingClient(grpcConnection))
+		if err == nil {
+			return nil
+		}
+		lastErr = err
+	}
+
+	return lastErr
+}
diff --git a/weed/messaging/msgclient/publisher.go b/weed/messaging/msgclient/publisher.go
new file mode 100644
index 000000000..1aa483ff8
--- /dev/null
+++ b/weed/messaging/msgclient/publisher.go
@@ -0,0 +1,118 @@
+package msgclient
+
+import (
+	"context"
+
+	"github.com/OneOfOne/xxhash"
+	"google.golang.org/grpc"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+)
+
+type Publisher struct {
+	publishClients     []messaging_pb.SeaweedMessaging_PublishClient
+	topicConfiguration *messaging_pb.TopicConfiguration
+	messageCount       uint64
+	publisherId        string
+}
+
+func (mc *MessagingClient) NewPublisher(publisherId, namespace, topic string) (*Publisher, error) {
+	// read topic configuration
+	topicConfiguration := &messaging_pb.TopicConfiguration{
+		PartitionCount: 4,
+	}
+	publishClients := make([]messaging_pb.SeaweedMessaging_PublishClient, topicConfiguration.PartitionCount)
+	for i := 0; i < int(topicConfiguration.PartitionCount); i++ {
+		tp := broker.TopicPartition{
+			Namespace: namespace,
+			Topic:     topic,
+			Partition: int32(i),
+		}
+		grpcClientConn, err := mc.findBroker(tp)
+		if err != nil {
+			return nil, err
+		}
+		client, err := setupPublisherClient(grpcClientConn, tp)
+		if err != nil {
+			return nil, err
+		}
+		publishClients[i] = client
+	}
+	return &Publisher{
+		publishClients:     publishClients,
+		topicConfiguration: topicConfiguration,
+	}, nil
+}
+
+func setupPublisherClient(grpcConnection *grpc.ClientConn, tp broker.TopicPartition) (messaging_pb.SeaweedMessaging_PublishClient, error) {
+
+	stream, err := messaging_pb.NewSeaweedMessagingClient(grpcConnection).Publish(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	// send init message
+	err = stream.Send(&messaging_pb.PublishRequest{
+		Init: &messaging_pb.PublishRequest_InitMessage{
+			Namespace: tp.Namespace,
+			Topic:     tp.Topic,
+			Partition: tp.Partition,
+		},
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	// process init response
+	initResponse, err := stream.Recv()
+	if err != nil {
+		return nil, err
+	}
+	if initResponse.Redirect != nil {
+		// TODO follow redirection
+	}
+	if initResponse.Config != nil {
+	}
+
+	// setup looks for control messages
+	doneChan := make(chan error, 1)
+	go func() {
+		for {
+			in, err := stream.Recv()
+			if err != nil {
+				doneChan <- err
+				return
+			}
+			if in.Redirect != nil {
+			}
+			if in.Config != nil {
+			}
+		}
+	}()
+
+	return stream, nil
+
+}
+
+func (p *Publisher) Publish(m *messaging_pb.Message) error {
+	hashValue := p.messageCount
+	p.messageCount++
+	if p.topicConfiguration.Partitoning == messaging_pb.TopicConfiguration_NonNullKeyHash {
+		if m.Key != nil {
+			hashValue = xxhash.Checksum64(m.Key)
+		}
+	} else if p.topicConfiguration.Partitoning == messaging_pb.TopicConfiguration_KeyHash {
+		hashValue = xxhash.Checksum64(m.Key)
+	} else {
+		// round robin
+	}
+
+	idx := int(hashValue) % len(p.publishClients)
+	if idx < 0 {
+		idx += len(p.publishClients)
+	}
+	return p.publishClients[idx].Send(&messaging_pb.PublishRequest{
+		Data: m,
+	})
+}
diff --git a/weed/messaging/msgclient/subscriber.go b/weed/messaging/msgclient/subscriber.go
new file mode 100644
index 000000000..6c7dc1ab7
--- /dev/null
+++ b/weed/messaging/msgclient/subscriber.go
@@ -0,0 +1,120 @@
+package msgclient
+
+import (
+	"context"
+	"io"
+	"sync"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+	"google.golang.org/grpc"
+)
+
+type Subscriber struct {
+	subscriberClients []messaging_pb.SeaweedMessaging_SubscribeClient
+	subscriberCancels []context.CancelFunc
+	subscriberId      string
+}
+
+func (mc *MessagingClient) NewSubscriber(subscriberId, namespace, topic string, partitionId int, startTime time.Time) (*Subscriber, error) {
+	// read topic configuration
+	topicConfiguration := &messaging_pb.TopicConfiguration{
+		PartitionCount: 4,
+	}
+	subscriberClients := make([]messaging_pb.SeaweedMessaging_SubscribeClient, topicConfiguration.PartitionCount)
+	subscriberCancels := make([]context.CancelFunc, topicConfiguration.PartitionCount)
+
+	for i := 0; i < int(topicConfiguration.PartitionCount); i++ {
+		if partitionId >= 0 && i != partitionId {
+			continue
+		}
+		tp := broker.TopicPartition{
+			Namespace: namespace,
+			Topic:     topic,
+			Partition: int32(i),
+		}
+		grpcClientConn, err := mc.findBroker(tp)
+		if err != nil {
+			return nil, err
+		}
+		ctx, cancel := context.WithCancel(context.Background())
+		client, err := setupSubscriberClient(ctx, grpcClientConn, tp, subscriberId, startTime)
+		if err != nil {
+			return nil, err
+		}
+		subscriberClients[i] = client
+		subscriberCancels[i] = cancel
+	}
+
+	return &Subscriber{
+		subscriberClients: subscriberClients,
+		subscriberCancels: subscriberCancels,
+		subscriberId:      subscriberId,
+	}, nil
+}
+
+func setupSubscriberClient(ctx context.Context, grpcConnection *grpc.ClientConn, tp broker.TopicPartition, subscriberId string, startTime time.Time) (stream messaging_pb.SeaweedMessaging_SubscribeClient, err error) {
+	stream, err = messaging_pb.NewSeaweedMessagingClient(grpcConnection).Subscribe(ctx)
+	if err != nil {
+		return
+	}
+
+	// send init message
+	err = stream.Send(&messaging_pb.SubscriberMessage{
+		Init: &messaging_pb.SubscriberMessage_InitMessage{
+			Namespace:     tp.Namespace,
+			Topic:         tp.Topic,
+			Partition:     tp.Partition,
+			StartPosition: messaging_pb.SubscriberMessage_InitMessage_TIMESTAMP,
+			TimestampNs:   startTime.UnixNano(),
+			SubscriberId:  subscriberId,
+		},
+	})
+	if err != nil {
+		return
+	}
+
+	return stream, nil
+}
+
+func doSubscribe(subscriberClient messaging_pb.SeaweedMessaging_SubscribeClient, processFn func(m *messaging_pb.Message)) error {
+	for {
+		resp, listenErr := subscriberClient.Recv()
+		if listenErr == io.EOF {
+			return nil
+		}
+		if listenErr != nil {
+			println(listenErr.Error())
+			return listenErr
+		}
+		if resp.Data == nil {
+			// this could be heartbeat from broker
+			continue
+		}
+		processFn(resp.Data)
+	}
+}
+
+// Subscribe starts goroutines to process the messages
+func (s *Subscriber) Subscribe(processFn func(m *messaging_pb.Message)) {
+	var wg sync.WaitGroup
+	for i := 0; i < len(s.subscriberClients); i++ {
+		if s.subscriberClients[i] != nil {
+			wg.Add(1)
+			go func(subscriberClient messaging_pb.SeaweedMessaging_SubscribeClient) {
+				defer wg.Done()
+				doSubscribe(subscriberClient, processFn)
+			}(s.subscriberClients[i])
+		}
+	}
+	wg.Wait()
+}
+
+func (s *Subscriber) Shutdown() {
+	for i := 0; i < len(s.subscriberClients); i++ {
+		if s.subscriberCancels[i] != nil {
+			s.subscriberCancels[i]()
+		}
+	}
+}