1 files changed, 177 insertions, 0 deletions
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)
+
+}