Enable placement rules automatically (#2328)

pkg/manager/member/pd_member_manager.go

@@ -741,17 +741,7 @@ func getPDConfigMap(tc *v1alpha1.TidbCluster) (*corev1.ConfigMap, error) {
 		config.Dashboard.TiDBCertPath = path.Join(tidbClientCertPath, corev1.TLSCertKey)
 		config.Dashboard.TiDBKeyPath = path.Join(tidbClientCertPath, corev1.TLSPrivateKeyKey)
 	}
-	// TiFlash requires PD to enable the `replication.enable-placement-rules`
-	// Check detail in https://pingcap.com/docs/stable/reference/tiflash/deploy/
-	if tc.Spec.TiFlash != nil {
-		if config.Replication == nil {
-			config.Replication = &v1alpha1.PDReplicationConfig{}
-		}
-		if config.Replication.EnablePlacementRules == nil {
-			enable := true
-			config.Replication.EnablePlacementRules = &enable
-		}
-	}
+
 	confText, err := MarshalTOML(config)
 	if err != nil {
 		return nil, err

pkg/manager/member/tiflash_member_manager.go

@@ -107,14 +107,36 @@ func (tfmm *tiflashMemberManager) Sync(tc *v1alpha1.TidbCluster) error {
 		return controller.RequeueErrorf("TidbCluster: [%s/%s], waiting for PD cluster running", ns, tcName)
 	}
 
+	err := tfmm.enablePlacementRules(tc)
+	if err != nil {
+		klog.Errorf("Enable placement rules failed, error: %v", err)
+		// No need to return err here, just continue to sync tiflash
+	}
 	// Sync TiFlash Headless Service
-	if err := tfmm.syncHeadlessService(tc); err != nil {
+	if err = tfmm.syncHeadlessService(tc); err != nil {
 		return err
 	}
 
 	return tfmm.syncStatefulSet(tc)
 }
 
+func (tfmm *tiflashMemberManager) enablePlacementRules(tc *v1alpha1.TidbCluster) error {
+	pdCli := controller.GetPDClient(tfmm.pdControl, tc)
+	config, err := pdCli.GetConfig()
+	if err != nil {
+		return err
+	}
+	if config.Replication.EnablePlacementRules != nil && (!*config.Replication.EnablePlacementRules) {
+		klog.Infof("Cluster %s/%s enable-placement-rules is %v, set it to true", tc.Namespace, tc.Name, *config.Replication.EnablePlacementRules)
+		enable := true
+		rep := pdapi.PDReplicationConfig{
+			EnablePlacementRules: &enable,
+		}
+		return pdCli.UpdateReplicationConfig(rep)
+	}
+	return nil
+}
+
 func (tfmm *tiflashMemberManager) syncHeadlessService(tc *v1alpha1.TidbCluster) error {
 	if tc.Spec.Paused {
 		klog.V(4).Infof("tiflash cluster %s/%s is paused, skip syncing for tiflash service", tc.GetNamespace(), tc.GetName())

pkg/pdapi/pdapi.go

@@ -154,6 +154,8 @@ type PDClient interface {
 	// storeLabelsEqualNodeLabels compares store labels with node labels
 	// for historic reasons, PD stores TiKV labels as []*StoreLabel which is a key-value pair slice
 	SetStoreLabels(storeID uint64, labels map[string]string) (bool, error)
+	// UpdateReplicationConfig updates the replication config
+	UpdateReplicationConfig(config PDReplicationConfig) error
 	// DeleteStore deletes a TiKV store from cluster
 	DeleteStore(storeID uint64) error
 	// SetStoreState sets store to specified state.
@@ -185,6 +187,7 @@ var (
 	schedulersPrefix       = "pd/api/v1/schedulers"
 	pdLeaderPrefix         = "pd/api/v1/leader"
 	pdLeaderTransferPrefix = "pd/api/v1/leader/transfer"
+	pdReplicationPrefix    = "pd/api/v1/config/replicate"
 )
 
 // pdClient is default implementation of PDClient
@@ -512,6 +515,24 @@ func (pc *pdClient) SetStoreLabels(storeID uint64, labels map[string]string) (bo
 	return false, fmt.Errorf("failed %v to set store labels: %v", res.StatusCode, err2)
 }
 
+func (pc *pdClient) UpdateReplicationConfig(config PDReplicationConfig) error {
+	apiURL := fmt.Sprintf("%s/%s", pc.url, pdReplicationPrefix)
+	data, err := json.Marshal(config)
+	if err != nil {
+		return err
+	}
+	res, err := pc.httpClient.Post(apiURL, "application/json", bytes.NewBuffer(data))
+	if err != nil {
+		return err
+	}
+	defer httputil.DeferClose(res.Body)
+	if res.StatusCode == http.StatusOK {
+		return nil
+	}
+	err = httputil.ReadErrorBody(res.Body)
+	return fmt.Errorf("failed %v to update replication: %v", res.StatusCode, err)
+}
+
 func (pc *pdClient) BeginEvictLeader(storeID uint64) error {
 	leaderEvictInfo := getLeaderEvictSchedulerInfo(storeID)
 	apiURL := fmt.Sprintf("%s/%s", pc.url, schedulersPrefix)
@@ -697,6 +718,7 @@ const (
 	DeleteMemberByIDActionType         ActionType = "DeleteMemberByID"
 	DeleteMemberActionType             ActionType = "DeleteMember "
 	SetStoreLabelsActionType           ActionType = "SetStoreLabels"
+	UpdateReplicationActionType        ActionType = "UpdateReplicationConfig"
 	BeginEvictLeaderActionType         ActionType = "BeginEvictLeader"
 	EndEvictLeaderActionType           ActionType = "EndEvictLeader"
 	GetEvictLeaderSchedulersActionType ActionType = "GetEvictLeaderSchedulers"
@@ -713,9 +735,10 @@ func (nfr *NotFoundReaction) Error() string {
 }
 
 type Action struct {
-	ID     uint64
-	Name   string
-	Labels map[string]string
+	ID          uint64
+	Name        string
+	Labels      map[string]string
+	Replication PDReplicationConfig
 }
 
 type Reaction func(action *Action) (interface{}, error)
@@ -855,6 +878,16 @@ func (pc *FakePDClient) SetStoreLabels(storeID uint64, labels map[string]string)
 	return true, nil
 }
 
+// UpdateReplicationConfig updates the replication config
+func (pc *FakePDClient) UpdateReplicationConfig(config PDReplicationConfig) error {
+	if reaction, ok := pc.reactions[UpdateReplicationActionType]; ok {
+		action := &Action{Replication: config}
+		_, err := reaction(action)
+		return err
+	}
+	return nil
+}
+
 func (pc *FakePDClient) BeginEvictLeader(storeID uint64) error {
 	if reaction, ok := pc.reactions[BeginEvictLeaderActionType]; ok {
 		action := &Action{ID: storeID}