mirror of
https://github.com/seaweedfs/seaweedfs.git
synced 2024-01-19 02:48:24 +00:00
97 lines
2.3 KiB
Go
97 lines
2.3 KiB
Go
package broker
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
"time"
|
|
|
|
"github.com/golang/protobuf/proto"
|
|
|
|
"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 messageCount int64
|
|
subscriberId := in.Init.SubscriberId
|
|
fmt.Printf("+ subscriber %s\n", subscriberId)
|
|
defer func() {
|
|
fmt.Printf("- subscriber %s: %d messages\n", subscriberId, messageCount)
|
|
}()
|
|
|
|
// TODO look it up
|
|
topicConfig := &messaging_pb.TopicConfiguration{
|
|
IsTransient: true,
|
|
}
|
|
|
|
if err = stream.Send(&messaging_pb.BrokerMessage{
|
|
Redirect: nil,
|
|
}); err != nil {
|
|
return err
|
|
}
|
|
|
|
// get lock
|
|
tp := TopicPartition{
|
|
Namespace: in.Init.Namespace,
|
|
Topic: in.Init.Topic,
|
|
Partition: in.Init.Partition,
|
|
}
|
|
lock := broker.topicLocks.RequestLock(tp, topicConfig, false)
|
|
defer broker.topicLocks.ReleaseLock(tp, false)
|
|
|
|
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
|
|
}
|
|
|
|
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\n", len(m.Value))
|
|
if err = eachMessageFn(m); err != nil {
|
|
glog.Errorf("sending %d bytes to %s: %s", len(m.Value), subscriberId, err)
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
messageCount, err = lock.logBuffer.LoopProcessLogData(lastReadTime, func() bool {
|
|
lock.Mutex.Lock()
|
|
lock.cond.Wait()
|
|
lock.Mutex.Unlock()
|
|
return true
|
|
}, eachLogEntryFn)
|
|
|
|
return err
|
|
|
|
}
|