streamer: add heartbeat for local streamer

pkg/streamer/reader_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/google/uuid"
 	. "github.com/pingcap/check"
 	"github.com/pingcap/errors"
+	"github.com/pingcap/failpoint"
 	"github.com/siddontang/go-mysql/mysql"
 	gmysql "github.com/siddontang/go-mysql/mysql"
 	"github.com/siddontang/go-mysql/replication"
@@ -62,6 +63,11 @@ func (t *testReaderSuite) SetUpSuite(c *C) {
 	t.lastPos = 0
 	t.lastGTID, err = gtid.ParserGTID(mysql.MySQLFlavor, "ba8f633f-1f15-11eb-b1c7-0242ac110002:0")
 	c.Assert(err, IsNil)
+	c.Assert(failpoint.Enable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval", "return(10000)"), IsNil)
+}
+
+func (t *testReaderSuite) TearDownSuite(c *C) {
+	c.Assert(failpoint.Disable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval"), IsNil)
 }
 
 func (t *testReaderSuite) TestParseFileBase(c *C) {

pkg/streamer/streamer.go

@@ -15,7 +15,9 @@ package streamer
 
 import (
 	"context"
+	"time"
 
+	"github.com/pingcap/dm/pkg/binlog/event"
 	"github.com/pingcap/dm/pkg/log"
 	"github.com/pingcap/dm/pkg/terror"
 
@@ -51,7 +53,21 @@ func (s *LocalStreamer) GetEvent(ctx context.Context) (*replication.BinlogEvent,
 		failpoint.Return(nil, terror.ErrSyncClosed.Generate())
 	})
 
+	// MySQL will send heartbeat event 30s by default
+	heartbeatTicker := time.NewTicker(30 * time.Second)
+	heartbeatHeader := &replication.EventHeader{}
+	defer heartbeatTicker.Stop()
+
+	failpoint.Inject("SetHeartbeatInterval", func(v failpoint.Value) {
+		i := v.(int)
+		log.L().Info("will change heartbeat interval", zap.Int("new", i))
+		heartbeatTicker.Stop()
+		heartbeatTicker = time.NewTicker(time.Duration(i) * time.Second)
+	})
+
 	select {
+	case <-heartbeatTicker.C:
+		return event.GenHeartbeatEvent(heartbeatHeader), nil
 	case c := <-s.ch:
 		return c, nil
 	case s.err = <-s.ech:

pkg/streamer/streamer_test.go

@@ -19,6 +19,7 @@ import (
 
 	. "github.com/pingcap/check"
 	"github.com/pingcap/errors"
+	"github.com/pingcap/failpoint"
 	"github.com/siddontang/go-mysql/replication"
 
 	"github.com/pingcap/dm/pkg/binlog/event"
@@ -31,6 +32,9 @@ type testStreamerSuite struct {
 }
 
 func (t *testStreamerSuite) TestStreamer(c *C) {
+	c.Assert(failpoint.Enable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval", "return(10000)"), IsNil)
+	defer c.Assert(failpoint.Disable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval"), IsNil)
+
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 	defer cancel()
 
@@ -98,3 +102,15 @@ func (t *testStreamerSuite) TestStreamer(c *C) {
 	c.Assert(terror.ErrNeedSyncAgain.Equal(err), IsTrue)
 	c.Assert(ev2, IsNil)
 }
+
+func (t *testStreamerSuite) TestHeartbeat(c *C) {
+	c.Assert(failpoint.Enable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval", "return(1)"), IsNil)
+	defer c.Assert(failpoint.Disable("github.com/pingcap/dm/pkg/streamer/SetHeartbeatInterval"), IsNil)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+	s := newLocalStreamer() // with buffer
+	ev, err := s.GetEvent(ctx)
+	c.Assert(err, IsNil)
+	c.Assert(ev.Header.EventType, Equals, replication.HEARTBEAT_EVENT)
+}