tp: add info provider (pingcap#5844)

Signed-off-by: Neil Shen <overvenus@gmail.com>

cdc/scheduler/internal/info_provider.go

@@ -24,13 +24,22 @@ type InfoProvider interface {
 	GetTaskStatuses() (map[model.CaptureID]*model.TaskStatus, error)
 
 	// GetTaskPositions returns the task positions.
+	//
+	// TODO: Remove the API, as capture no longer has local checkpoint ts and
+	//       local resolved ts in tpscheduler.
 	GetTaskPositions() (map[model.CaptureID]*model.TaskPosition, error)
 
 	// GetTotalTableCounts returns the number of tables associated
 	// with each capture.
+	//
+	// TODO: Remove the API, as the only usage is metrics which
+	//       has already exported in the scheduler package.
 	GetTotalTableCounts() map[model.CaptureID]int
 
 	// GetPendingTableCounts returns the number of tables in a non-ready
 	// status (Adding & Removing) associated with each capture.
+	//
+	// TODO: Remove the API, as the only usage is metrics which
+	//       has already exported in the scheduler package.
 	GetPendingTableCounts() map[model.CaptureID]int
 }

cdc/scheduler/internal/tp/coordinator.go

@@ -15,6 +15,7 @@ package tp
 
 import (
 	"context"
+	"sync"
 	"sync/atomic"
 	"time"
 
@@ -37,6 +38,10 @@ const (
 var _ internal.Scheduler = (*coordinator)(nil)
 
 type coordinator struct {
+	// A mutex for concurrent access of coordinator in
+	// internal.Scheduler and internal.InfoProvider API.
+	mu sync.Mutex
+
 	version      string
 	revision     schedulepb.OwnerRevision
 	captureID    model.CaptureID
@@ -105,10 +110,16 @@ func (c *coordinator) Tick(
 	// All captures that are alive according to the latest Etcd states.
 	aliveCaptures map[model.CaptureID]*model.CaptureInfo,
 ) (newCheckpointTs, newResolvedTs model.Ts, err error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
 	return c.poll(ctx, checkpointTs, currentTables, aliveCaptures)
 }
 
 func (c *coordinator) MoveTable(tableID model.TableID, target model.CaptureID) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
 	if !c.captureM.CheckAllCaptureInitialized() {
 		log.Info("tpscheduler: manual move table task ignored, "+
 			"since not all captures initialized",
@@ -133,6 +144,9 @@ func (c *coordinator) MoveTable(tableID model.TableID, target model.CaptureID) {
 }
 
 func (c *coordinator) Rebalance() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
 	if !c.captureM.CheckAllCaptureInitialized() {
 		log.Info("tpscheduler: manual rebalance task ignored, " +
 			"since not all captures initialized")
@@ -150,6 +164,9 @@ func (c *coordinator) Rebalance() {
 }
 
 func (c *coordinator) Close(ctx context.Context) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
 	_ = c.trans.Close()
 }
 

cdc/scheduler/internal/tp/info_provider.go

@@ -0,0 +1,73 @@
+// Copyright 2022 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tp
+
+import (
+	"github.com/pingcap/tiflow/cdc/model"
+	"github.com/pingcap/tiflow/cdc/scheduler/internal"
+)
+
+var _ internal.InfoProvider = (*coordinator)(nil)
+
+// GetTaskStatuses returns the task statuses.
+func (c *coordinator) GetTaskStatuses() (map[model.CaptureID]*model.TaskStatus, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	tasks := make(map[model.CaptureID]*model.TaskStatus, len(c.captureM.Captures))
+	for captureID, status := range c.captureM.Captures {
+		taskStatus := &model.TaskStatus{
+			Tables: make(map[model.TableID]*model.TableReplicaInfo),
+		}
+		for _, s := range status.Tables {
+			taskStatus.Tables[s.TableID] = &model.TableReplicaInfo{
+				StartTs: s.Checkpoint.CheckpointTs,
+			}
+		}
+		tasks[captureID] = taskStatus
+	}
+	return tasks, nil
+}
+
+// GetTaskPositions returns the task positions.
+func (c *coordinator) GetTaskPositions() (map[model.CaptureID]*model.TaskPosition, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	p := &model.TaskPosition{}
+	pos := make(map[model.CaptureID]*model.TaskPosition, len(c.captureM.Captures))
+	for captureID := range c.captureM.Captures {
+		pos[captureID] = p
+	}
+	return pos, nil
+}
+
+// GetTotalTableCounts returns the number of tables associated
+// with each capture.
+func (c *coordinator) GetTotalTableCounts() map[model.CaptureID]int {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	tables := make(map[model.CaptureID]int, len(c.captureM.Captures))
+	for captureID, status := range c.captureM.Captures {
+		tables[captureID] = len(status.Tables)
+	}
+	return tables
+}
+
+// GetPendingTableCounts returns the number of tables in a non-ready
+// status (Adding & Removing) associated with each capture.
+func (c *coordinator) GetPendingTableCounts() map[model.CaptureID]int {
+	return make(map[model.CaptureID]int)
+}

cdc/scheduler/internal/tp/info_provider_test.go

@@ -0,0 +1,61 @@
+// Copyright 2022 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tp
+
+import (
+	"math"
+	"testing"
+
+	"github.com/pingcap/tiflow/cdc/model"
+	"github.com/pingcap/tiflow/cdc/scheduler/internal"
+	"github.com/pingcap/tiflow/cdc/scheduler/internal/tp/schedulepb"
+	"github.com/pingcap/tiflow/pkg/config"
+	"github.com/stretchr/testify/require"
+)
+
+func TestInfoProvider(t *testing.T) {
+	t.Parallel()
+
+	coord := newCoordinator("a", model.ChangeFeedID{}, 1, &config.SchedulerConfig{
+		HeartbeatTick:      math.MaxInt,
+		MaxTaskConcurrency: 1,
+	})
+	coord.captureM.Captures = map[model.CaptureID]*CaptureStatus{
+		"a": {Tables: []schedulepb.TableStatus{{
+			TableID:    1,
+			Checkpoint: schedulepb.Checkpoint{CheckpointTs: 1},
+		}, {
+			TableID:    2,
+			Checkpoint: schedulepb.Checkpoint{CheckpointTs: 1},
+		}}},
+		"b": {},
+	}
+
+	// Smoke testing
+	var ip internal.InfoProvider = coord
+	tasks, err := ip.GetTaskStatuses()
+	require.Nil(t, err)
+	require.EqualValues(t, map[model.CaptureID]*model.TaskStatus{
+		"a": {Tables: map[model.TableID]*model.TableReplicaInfo{
+			1: {StartTs: 1},
+			2: {StartTs: 1},
+		}},
+		"b": {Tables: map[model.TableID]*model.TableReplicaInfo{}},
+	}, tasks)
+	pos, err := ip.GetTaskPositions()
+	require.Nil(t, err)
+	require.Len(t, pos, 2)
+	require.Len(t, ip.GetTotalTableCounts(), 2)
+	require.Empty(t, ip.GetPendingTableCounts())
+}