Add msgstream seek (#5483)

* Add msgstream seek
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

* fix error
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

* change test name
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

* fix error
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

* remove file
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

* resolve conversation
Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

internal/msgstream/mq_msgstream.go

@@ -12,6 +12,7 @@
 package msgstream
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
@@ -128,8 +129,6 @@ func (ms *mqMsgStream) AsConsumer(channels []string, subName string) {
 			ms.consumers[channel] = pc
 			ms.consumerChannels = append(ms.consumerChannels, channel)
 			ms.consumerLock.Unlock()
-			ms.wait.Add(1)
-			go ms.receiveMsg(pc)
 			return nil
 		}
 		err := Retry(20, time.Millisecond*200, fn)
@@ -145,6 +144,10 @@ func (ms *mqMsgStream) SetRepackFunc(repackFunc RepackFunc) {
 }
 
 func (ms *mqMsgStream) Start() {
+	for _, c := range ms.consumers {
+		ms.wait.Add(1)
+		go ms.receiveMsg(c)
+	}
 }
 
 func (ms *mqMsgStream) Close() {
@@ -351,7 +354,11 @@ func (ms *mqMsgStream) receiveMsg(consumer mqclient.Consumer) {
 				tsMsg.SetTraceCtx(opentracing.ContextWithSpan(context.Background(), sp))
 			}
 
-			msgPack := MsgPack{Msgs: []TsMsg{tsMsg}}
+			msgPack := MsgPack{
+				Msgs:           []TsMsg{tsMsg},
+				StartPositions: []*internalpb.MsgPosition{tsMsg.Position()},
+				EndPositions:   []*internalpb.MsgPosition{tsMsg.Position()},
+			}
 			ms.receiveBuf <- &msgPack
 
 			sp.Finish()
@@ -377,6 +384,18 @@ func (ms *mqMsgStream) Seek(msgPositions []*internalpb.MsgPosition) error {
 		if err != nil {
 			return err
 		}
+		msg, ok := <-consumer.Chan()
+		if !ok {
+			return errors.New("consumer closed")
+		}
+		consumer.Ack(msg)
+
+		if !bytes.Equal(msg.ID().Serialize(), messageID.Serialize()) {
+			err = fmt.Errorf("seek msg not correct")
+			log.Error("msMsgStream seek", zap.Error(err))
+		}
+
+		return nil
 	}
 	return nil
 }

internal/msgstream/mq_msgstream_test.go

@@ -881,6 +881,49 @@ func TestStream_PulsarTtMsgStream_2(t *testing.T) {
 	inputStream2.Close()
 }
 
+func TestStream_MqMsgStream_Seek(t *testing.T) {
+	pulsarAddress, _ := Params.Load("_PulsarAddress")
+	c := funcutil.RandomString(8)
+	producerChannels := []string{c}
+	consumerChannels := []string{c}
+	consumerSubName := funcutil.RandomString(8)
+
+	msgPack := &MsgPack{}
+	inputStream := getPulsarInputStream(pulsarAddress, producerChannels)
+	outputStream := getPulsarOutputStream(pulsarAddress, consumerChannels, consumerSubName)
+
+	for i := 0; i < 10; i++ {
+		insertMsg := getTsMsg(commonpb.MsgType_Insert, int64(i))
+		msgPack.Msgs = append(msgPack.Msgs, insertMsg)
+	}
+
+	err := inputStream.Produce(msgPack)
+	assert.Nil(t, err)
+	var seekPosition *internalpb.MsgPosition
+	for i := 0; i < 10; i++ {
+		result := outputStream.Consume()
+		assert.Equal(t, result.Msgs[0].ID(), int64(i))
+		if i == 5 {
+			seekPosition = result.EndPositions[0]
+		}
+	}
+	outputStream.Close()
+
+	factory := ProtoUDFactory{}
+	pulsarClient, _ := mqclient.NewPulsarClient(pulsar.ClientOptions{URL: pulsarAddress})
+	outputStream2, _ := NewMqMsgStream(context.Background(), 100, 100, pulsarClient, factory.NewUnmarshalDispatcher())
+	outputStream2.AsConsumer(consumerChannels, consumerSubName)
+	outputStream2.Seek([]*internalpb.MsgPosition{seekPosition})
+	outputStream2.Start()
+
+	for i := 6; i < 10; i++ {
+		result := outputStream2.Consume()
+		assert.Equal(t, result.Msgs[0].ID(), int64(i))
+	}
+	outputStream2.Close()
+
+}
+
 /****************************************Rmq test******************************************/
 
 func initRmq(name string) *etcdkv.EtcdKV {