messaging can compile now

weed/command/msg_broker.go

@@ -9,7 +9,7 @@ import (
 	"google.golang.org/grpc/reflection"
 
 	"github.com/chrislusf/seaweedfs/weed/glog"
-	"github.com/chrislusf/seaweedfs/weed/messaging"
+	"github.com/chrislusf/seaweedfs/weed/messaging/broker"
 	"github.com/chrislusf/seaweedfs/weed/pb"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
@@ -80,7 +80,7 @@ func (msgBrokerOpt *QueueOptions) startQueueServer() bool {
 		}
 	}
 
-	qs, err := messaging.NewMessageBroker(&messaging.MessageBrokerOption{
+	qs, err := broker.NewMessageBroker(&broker.MessageBrokerOption{
 		Filers:             []string{*msgBrokerOpt.filer},
 		DefaultReplication: "",
 		MaxMB:              0,

weed/messaging/broker/broker_append.go

@@ -1,4 +1,4 @@
-package messaging
+package broker
 
 import (
 	"context"

weed/messaging/broker/broker_grpc_server.go

@@ -1,4 +1,4 @@
-package messaging
+package broker
 
 import (
 	"context"

weed/messaging/broker/broker_grpc_server_publish.go

@@ -1,4 +1,4 @@
-package messaging
+package broker
 
 import (
 	"fmt"
@@ -10,7 +10,6 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
-	"github.com/chrislusf/seaweedfs/weed/util/log_buffer"
 )
 
 func (broker *MessageBroker) Publish(stream messaging_pb.SeaweedMessaging_PublishServer) error {
@@ -23,15 +22,36 @@ func (broker *MessageBroker) Publish(stream messaging_pb.SeaweedMessaging_Publis
 	if err != nil {
 		return err
 	}
-	namespace, topic, partition := in.Init.Namespace, in.Init.Topic, in.Init.Partition
-
-	updatesChan := make(chan int32)
 
 	// TODO look it up
 	topicConfig := &messaging_pb.TopicConfiguration{
 
 	}
 
+	// get lock
+	tp := TopicPartition{
+		Namespace: in.Init.Namespace,
+		Topic:     in.Init.Topic,
+		Partition: in.Init.Partition,
+	}
+	logBuffer := broker.topicLocks.RequestPublisherLock(tp, func(startTime, stopTime time.Time, buf []byte) {
+
+		targetFile := fmt.Sprintf(
+			"%s/%s/%s/%04d-%02d-%02d/%02d-%02d.part%02d",
+			filer2.TopicsDir, tp.Namespace, tp.Topic,
+			startTime.Year(), startTime.Month(), startTime.Day(), startTime.Hour(), startTime.Minute(),
+			tp.Partition,
+		)
+
+		if err := broker.appendToFile(targetFile, topicConfig, buf); err != nil {
+			glog.V(0).Infof("log write failed %s: %v", targetFile, err)
+		}
+
+	})
+	defer broker.topicLocks.ReleaseLock(tp, true)
+
+	updatesChan := make(chan int32)
+
 	go func() {
 		for update := range updatesChan {
 			if err := stream.Send(&messaging_pb.PublishResponse{
@@ -45,23 +65,8 @@ func (broker *MessageBroker) Publish(stream messaging_pb.SeaweedMessaging_Publis
 		}
 	}()
 
-	logBuffer := log_buffer.NewLogBuffer(time.Minute, func(startTime, stopTime time.Time, buf []byte) {
-
-		targetFile := fmt.Sprintf(
-			"%s/%s/%s/%04d-%02d-%02d/%02d-%02d.part%02d",
-			filer2.TopicsDir, namespace, topic,
-			startTime.Year(), startTime.Month(), startTime.Day(), startTime.Hour(), startTime.Minute(),
-			partition,
-		)
-
-		if err := broker.appendToFile(targetFile, topicConfig, buf); err != nil {
-			glog.V(0).Infof("log write failed %s: %v", targetFile, err)
-		}
-
-	}, func() {
-		// notify subscribers
-	})
 
+	// process each message
 	for {
 		in, err := stream.Recv()
 		if err == io.EOF {
@@ -71,6 +76,10 @@ func (broker *MessageBroker) Publish(stream messaging_pb.SeaweedMessaging_Publis
 			return err
 		}
 
+		if in.Data == nil {
+			continue
+		}
+
 		m := &messaging_pb.Message{
 			Timestamp: time.Now().UnixNano(),
 			Key:       in.Data.Key,

weed/messaging/broker/broker_grpc_server_subscribe.go

@@ -0,0 +1,88 @@
+package broker
+
+import (
+	"io"
+	"sync"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+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
+	}
+
+	subscriberId := in.Init.SubscriberId
+
+	// get lock
+	tp := TopicPartition{
+		Namespace: in.Init.Namespace,
+		Topic:     in.Init.Topic,
+		Partition: in.Init.Partition,
+	}
+	lock := broker.topicLocks.RequestSubscriberLock(tp)
+	defer broker.topicLocks.ReleaseLock(tp, false)
+	cond := sync.NewCond(&lock.Mutex)
+
+	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:
+	}
+
+	// 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
+	}
+
+	// loop through all messages
+	for {
+
+		_, buf := lock.logBuffer.ReadFromBuffer(lastReadTime)
+
+		for pos := 0; pos+4 < len(buf); {
+
+			size := util.BytesToUint32(buf[pos : pos+4])
+			entryData := buf[pos+4 : pos+4+int(size)]
+
+			m := &messaging_pb.Message{}
+			if err = proto.Unmarshal(entryData, m); err != nil {
+				glog.Errorf("unexpected unmarshal messaging_pb.Message: %v", err)
+				pos += 4 + int(size)
+				continue
+			}
+
+			if err = eachMessageFn(m); err != nil {
+				return err
+			}
+
+			lastReadTime = time.Unix(0, m.Timestamp)
+			pos += 4 + int(size)
+		}
+
+		lock.Mutex.Lock()
+		cond.Wait()
+		lock.Mutex.Unlock()
+	}
+
+}

weed/messaging/broker/broker_server.go

@@ -1,4 +1,4 @@
-package messaging
+package broker
 
 import (
 	"context"
@@ -23,6 +23,7 @@ type MessageBrokerOption struct {
 type MessageBroker struct {
 	option         *MessageBrokerOption
 	grpcDialOption grpc.DialOption
+	topicLocks     *TopicLocks
 }
 
 func NewMessageBroker(option *MessageBrokerOption, grpcDialOption grpc.DialOption) (messageBroker *MessageBroker, err error) {
@@ -30,6 +31,7 @@ func NewMessageBroker(option *MessageBrokerOption, grpcDialOption grpc.DialOptio
 	messageBroker = &MessageBroker{
 		option:         option,
 		grpcDialOption: grpcDialOption,
+		topicLocks:     NewTopicLocks(),
 	}
 
 	go messageBroker.loopForEver()

weed/messaging/broker/topic_lock.go

@@ -0,0 +1,80 @@
+package broker
+
+import (
+	"sync"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/util/log_buffer"
+)
+
+type TopicPartition struct {
+	Namespace string
+	Topic     string
+	Partition int32
+}
+type TopicLock struct {
+	sync.Mutex
+	subscriberCount int
+	publisherCount  int
+	logBuffer       *log_buffer.LogBuffer
+}
+
+type TopicLocks struct {
+	sync.Mutex
+	locks map[TopicPartition]*TopicLock
+}
+
+func NewTopicLocks() *TopicLocks {
+	return &TopicLocks{
+		locks: make(map[TopicPartition]*TopicLock),
+	}
+}
+
+func (tl *TopicLocks) RequestSubscriberLock(partition TopicPartition) *TopicLock {
+	tl.Lock()
+	defer tl.Unlock()
+
+	lock, found := tl.locks[partition]
+	if !found {
+		lock = &TopicLock{}
+		tl.locks[partition] = lock
+	}
+	lock.subscriberCount++
+
+	return lock
+}
+
+func (tl *TopicLocks) RequestPublisherLock(partition TopicPartition, flushFn func(startTime, stopTime time.Time, buf []byte)) *log_buffer.LogBuffer {
+	tl.Lock()
+	defer tl.Unlock()
+
+	lock, found := tl.locks[partition]
+	if !found {
+		lock = &TopicLock{}
+		tl.locks[partition] = lock
+	}
+	lock.publisherCount++
+	cond := sync.NewCond(&lock.Mutex)
+	lock.logBuffer = log_buffer.NewLogBuffer(time.Minute, flushFn, func() {
+		cond.Broadcast()
+	})
+	return lock.logBuffer
+}
+
+func (tl *TopicLocks) ReleaseLock(partition TopicPartition, isPublisher bool) {
+	tl.Lock()
+	defer tl.Unlock()
+
+	lock, found := tl.locks[partition]
+	if !found {
+		return
+	}
+	if isPublisher {
+		lock.publisherCount--
+	} else {
+		lock.subscriberCount--
+	}
+	if lock.subscriberCount <= 0 && lock.publisherCount <= 0 {
+		delete(tl.locks, partition)
+	}
+}

weed/messaging/broker_grpc_server_subscribe.go

@@ -1,9 +0,0 @@
-package messaging
-
-import (
-	"github.com/chrislusf/seaweedfs/weed/pb/messaging_pb"
-)
-
-func (broker *MessageBroker) Subscribe(server messaging_pb.SeaweedMessaging_SubscribeServer) error {
-	panic("implement me")
-}