7 files changed, 522 insertions, 0 deletions
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]()
+		}
+	}
+}