VStream API: allow keyspace-level heartbeats to be streamed (vitessio#16593)

Signed-off-by: Rohit Nayak <rohit@planetscale.com>

Author: rohit-nayak-ps

go/test/endtoend/vreplication/cluster_test.go

@@ -87,6 +87,9 @@ type ClusterConfig struct {
 	vtorcPort            int
 
 	vreplicationCompressGTID bool
+	// Set overrideHeartbeatOptions to true to override the default heartbeat options:
+	// which are set to only on demand (5s) and 250ms interval.
+	overrideHeartbeatOptions bool
 }
 
 // enableGTIDCompression enables GTID compression for the cluster and returns a function
@@ -519,12 +522,15 @@ func (vc *VitessCluster) AddKeyspace(t *testing.T, cells []*Cell, ksName string,
 // AddTablet creates new tablet with specified attributes
 func (vc *VitessCluster) AddTablet(t testing.TB, cell *Cell, keyspace *Keyspace, shard *Shard, tabletType string, tabletID int) (*Tablet, *exec.Cmd, error) {
 	tablet := &Tablet{}
-
-	options := []string{
-		"--queryserver-config-schema-reload-time", "5s",
+	var options []string
+	defaultHeartbeatOptions := []string{
 		"--heartbeat_on_demand_duration", "5s",
 		"--heartbeat_interval", "250ms",
-	} // FIXME: for multi-cell initial schema doesn't seem to load without "--queryserver-config-schema-reload-time"
+	}
+	if !mainClusterConfig.overrideHeartbeatOptions {
+		options = append(options, defaultHeartbeatOptions...)
+	}
+
 	options = append(options, extraVTTabletArgs...)
 
 	if mainClusterConfig.vreplicationCompressGTID {

go/test/endtoend/vreplication/vstream_test.go

@@ -555,3 +555,139 @@ func TestVStreamCopyMultiKeyspaceReshard(t *testing.T) {
 	require.NotZero(t, ne.numDash40Events)
 	require.NotZero(t, ne.num40DashEvents)
 }
+
+const (
+	vstreamHeartbeatsTestContextTimeout = 20 * time.Second
+	// Expect a reasonable number of heartbeats to be received in the test duration, should ideally be ~ timeout
+	// since the heartbeat interval is set to 1s. But we set it to 10 to be conservative to avoid CI flakiness.
+	numExpectedHeartbeats = 10
+)
+
+func doVStream(t *testing.T, vc *VitessCluster, flags *vtgatepb.VStreamFlags) (numRowEvents map[string]int, numFieldEvents map[string]int) {
+	// Stream for a while to ensure heartbeats are sent.
+	ctx, cancel := context.WithTimeout(context.Background(), vstreamHeartbeatsTestContextTimeout)
+	defer cancel()
+
+	numRowEvents = make(map[string]int)
+	numFieldEvents = make(map[string]int)
+	vstreamConn, err := vtgateconn.Dial(ctx, fmt.Sprintf("%s:%d", vc.ClusterConfig.hostname, vc.ClusterConfig.vtgateGrpcPort))
+	require.NoError(t, err)
+	defer vstreamConn.Close()
+
+	done := false
+	vgtid := &binlogdatapb.VGtid{
+		ShardGtids: []*binlogdatapb.ShardGtid{{
+			Keyspace: "product",
+			Shard:    "0",
+			Gtid:     "",
+		}}}
+
+	filter := &binlogdatapb.Filter{
+		Rules: []*binlogdatapb.Rule{{
+			Match:  "customer",
+			Filter: "select * from customer",
+		}},
+	}
+	// Stream events from the VStream API.
+	reader, err := vstreamConn.VStream(ctx, topodatapb.TabletType_PRIMARY, vgtid, filter, flags)
+	require.NoError(t, err)
+	for !done {
+		evs, err := reader.Recv()
+		switch err {
+		case nil:
+			for _, ev := range evs {
+				switch ev.Type {
+				case binlogdatapb.VEventType_ROW:
+					rowEvent := ev.RowEvent
+					arr := strings.Split(rowEvent.TableName, ".")
+					require.Equal(t, len(arr), 2)
+					tableName := arr[1]
+					require.Equal(t, "product", rowEvent.Keyspace)
+					require.Equal(t, "0", rowEvent.Shard)
+					numRowEvents[tableName]++
+
+				case binlogdatapb.VEventType_FIELD:
+					fieldEvent := ev.FieldEvent
+					arr := strings.Split(fieldEvent.TableName, ".")
+					require.Equal(t, len(arr), 2)
+					tableName := arr[1]
+					require.Equal(t, "product", fieldEvent.Keyspace)
+					require.Equal(t, "0", fieldEvent.Shard)
+					numFieldEvents[tableName]++
+				default:
+				}
+			}
+		case io.EOF:
+			log.Infof("Stream Ended")
+			done = true
+		default:
+			log.Errorf("remote error: %v", err)
+			done = true
+		}
+	}
+	return numRowEvents, numFieldEvents
+}
+
+// TestVStreamHeartbeats enables streaming of the internal Vitess heartbeat tables in the VStream API and
+// ensures that the heartbeat events are received as expected by the client.
+func TestVStreamHeartbeats(t *testing.T) {
+	// Enable continuous heartbeats.
+	extraVTTabletArgs = append(extraVTTabletArgs,
+		"--heartbeat_enable",
+		"--heartbeat_interval", "1s",
+		"--heartbeat_on_demand_duration", "0",
+	)
+	setSidecarDBName("_vt")
+	config := *mainClusterConfig
+	config.overrideHeartbeatOptions = true
+	vc = NewVitessCluster(t, &clusterOptions{
+		clusterConfig: &config,
+	})
+	defer vc.TearDown()
+
+	require.NotNil(t, vc)
+	defaultReplicas = 0
+	defaultRdonly = 0
+
+	defaultCell := vc.Cells[vc.CellNames[0]]
+	vc.AddKeyspace(t, []*Cell{defaultCell}, "product", "0", initialProductVSchema, initialProductSchema,
+		defaultReplicas, defaultRdonly, 100, nil)
+	verifyClusterHealth(t, vc)
+	insertInitialData(t)
+
+	expectedNumRowEvents := make(map[string]int)
+	expectedNumRowEvents["customer"] = 3 // 3 rows inserted in the customer table in insertInitialData()
+
+	type testCase struct {
+		name               string
+		flags              *vtgatepb.VStreamFlags
+		expectedHeartbeats int
+	}
+	testCases := []testCase{
+		{
+			name: "With Keyspace Heartbeats On",
+			flags: &vtgatepb.VStreamFlags{
+				StreamKeyspaceHeartbeats: true,
+			},
+			expectedHeartbeats: numExpectedHeartbeats,
+		},
+		{
+			name:               "With Keyspace Heartbeats Off",
+			flags:              nil,
+			expectedHeartbeats: 0,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			gotNumRowEvents, gotNumFieldEvents := doVStream(t, vc, tc.flags)
+			for k := range expectedNumRowEvents {
+				require.Equalf(t, 1, gotNumFieldEvents[k], "incorrect number of field events for table %s, got %d", k, gotNumFieldEvents[k])
+			}
+			require.GreaterOrEqual(t, gotNumRowEvents["heartbeat"], tc.expectedHeartbeats, "incorrect number of heartbeat events received")
+			log.Infof("Total number of heartbeat events received: %v", gotNumRowEvents["heartbeat"])
+			delete(gotNumRowEvents, "heartbeat")
+			require.Equal(t, expectedNumRowEvents, gotNumRowEvents)
+		})
+	}
+}