add api

Signed-off-by: husharp <[email protected]>

pkg/mcs/discovery/discover.go

@@ -15,6 +15,16 @@
 package discovery
 
 import (
+	"path"
+	"strconv"
+
+	"github.com/pingcap/errors"
+	"github.com/pingcap/kvproto/pkg/pdpb"
+	"github.com/tikv/pd/pkg/election"
+	"github.com/tikv/pd/pkg/errs"
+	"github.com/tikv/pd/pkg/mcs/utils"
+	"github.com/tikv/pd/pkg/storage/endpoint"
+	"github.com/tikv/pd/pkg/storage/kv"
 	"github.com/tikv/pd/pkg/utils/etcdutil"
 	"go.etcd.io/etcd/clientv3"
 )
@@ -35,3 +45,99 @@ func Discover(cli *clientv3.Client, clusterID, serviceName string) ([]string, er
 	}
 	return values, nil
 }
+
+func GetMCSPrimary(name string, client *clientv3.Client) (*pdpb.Member, int64, error) {
+	switch name {
+	case utils.TSOServiceName, utils.APIServiceName, utils.ResourceManagerServiceName:
+		clusterID, err := etcdutil.GetClusterID(client, utils.ClusterIDPath)
+		if err != nil {
+			return nil, 0, err
+		}
+		primaryPath := path.Join(endpoint.SvcRootPath(clusterID, name), utils.PrimaryKey)
+		return election.GetLeader(client, primaryPath)
+	default:
+	}
+	return nil, 0, errors.Errorf("unknown service name %s", name)
+}
+
+func GetMembers(name string, client *clientv3.Client) (*clientv3.TxnResponse, error) {
+	switch name {
+	case utils.TSOServiceName, utils.APIServiceName, utils.ResourceManagerServiceName:
+		clusterID, err := etcdutil.GetClusterID(client, utils.ClusterIDPath)
+		if err != nil {
+			return nil, err
+		}
+		servicePath := ServicePath(strconv.FormatUint(clusterID, 10), name)
+		resps, err := kv.NewSlowLogTxn(client).Then(clientv3.OpGet(servicePath, clientv3.WithPrefix())).Commit()
+		if err != nil {
+			return nil, errs.ErrEtcdKVGet.Wrap(err).GenWithStackByCause()
+		}
+		if !resps.Succeeded {
+			return nil, errs.ErrEtcdTxnConflict.FastGenByArgs()
+		}
+		if len(resps.Responses) == 0 {
+			return nil, errors.Errorf("no member found for service %s", name)
+		}
+		return resps, nil
+	}
+	return nil, errors.Errorf("unknown service name %s", name)
+}
+
+func DeleteMemberByName(name string, client *clientv3.Client) error {
+	resps, err := GetMembers(name, client)
+	if err != nil {
+		return err
+	}
+	for _, resp := range resps.Responses {
+		for _, keyValue := range resp.GetResponseRange().GetKvs() {
+			if name == string(keyValue.Value) {
+				// delete member
+				_, err := kv.NewSlowLogTxn(client).Then(clientv3.OpDelete(string(keyValue.Key))).Commit()
+				if err != nil {
+					return errs.ErrEtcdKVDelete.Wrap(err).GenWithStackByCause()
+				}
+				break
+			}
+		}
+	}
+	return nil
+}
+
+func TransferPrimaryLeader(name, newLeader string, client *clientv3.Client) error {
+	switch name {
+	case utils.TSOServiceName, utils.APIServiceName, utils.ResourceManagerServiceName:
+		clusterID, err := etcdutil.GetClusterID(client, utils.ClusterIDPath)
+		if err != nil {
+			return err
+		}
+		// delete leader
+		primaryPath := path.Join(endpoint.SvcRootPath(clusterID, name), utils.PrimaryKey)
+		resp, err := kv.NewSlowLogTxn(client).Then(clientv3.OpDelete(primaryPath)).Commit()
+		if err != nil {
+			return errs.ErrEtcdKVDelete.Wrap(err).GenWithStackByCause()
+		}
+		if !resp.Succeeded {
+			return errs.ErrEtcdTxnConflict.FastGenByArgs()
+		}
+		// set new leader
+		resps, err := GetMembers(name, client)
+		if err != nil {
+			return err
+		}
+		for _, resp := range resps.Responses {
+			for _, keyValue := range resp.GetResponseRange().GetKvs() {
+				if newLeader == string(keyValue.Value) {
+					// set new leader
+					_, err := kv.NewSlowLogTxn(client).Then(clientv3.OpPut(primaryPath, string(keyValue.Value))).Commit()
+					if err != nil {
+						return errs.ErrEtcdKVDelete.Wrap(err).GenWithStackByCause()
+					}
+					return nil
+				}
+			}
+		}
+
+	default:
+	}
+	return errors.Errorf("unknown service name %s", name)
+}

pkg/mcs/utils/util.go

@@ -45,8 +45,8 @@ import (
 const (
 	// maxRetryTimes is the max retry times for initializing the cluster ID.
 	maxRetryTimes = 5
-	// clusterIDPath is the path to store cluster id
-	clusterIDPath = "/pd/cluster_id"
+	// ClusterIDPath is the path to store cluster id
+	ClusterIDPath = "/pd/cluster_id"
 	// retryInterval is the interval to retry.
 	retryInterval = time.Second
 )
@@ -56,7 +56,7 @@ func InitClusterID(ctx context.Context, client *clientv3.Client) (id uint64, err
 	ticker := time.NewTicker(retryInterval)
 	defer ticker.Stop()
 	for i := 0; i < maxRetryTimes; i++ {
-		if clusterID, err := etcdutil.GetClusterID(client, clusterIDPath); err == nil && clusterID != 0 {
+		if clusterID, err := etcdutil.GetClusterID(client, ClusterIDPath); err == nil && clusterID != 0 {
 			return clusterID, nil
 		}
 		select {

pkg/member/participant.go

@@ -215,8 +215,8 @@ func (m *Participant) PreCheckLeader() error {
 	return nil
 }
 
-// getPersistentLeader gets the corresponding leader from etcd by given leaderPath (as the key).
-func (m *Participant) getPersistentLeader() (participant, int64, error) {
+// GetPersistentLeader gets the corresponding leader from etcd by given leaderPath (as the key).
+func (m *Participant) GetPersistentLeader() (participant, int64, error) {
 	leader := NewParticipantByService(m.serviceName)
 	ok, rev, err := etcdutil.GetProtoMsgWithModRev(m.client, m.GetLeaderPath(), leader)
 	if err != nil {
@@ -238,7 +238,7 @@ func (m *Participant) CheckLeader() (ElectionLeader, bool) {
 		return nil, true
 	}
 
-	leader, revision, err := m.getPersistentLeader()
+	leader, revision, err := m.GetPersistentLeader()
 	if err != nil {
 		log.Error("getting the leader meets error", errs.ZapError(err))
 		time.Sleep(200 * time.Millisecond)

pkg/storage/endpoint/key_path.go

@@ -291,22 +291,22 @@ func GetCompiledKeyspaceGroupIDRegexp() *regexp.Regexp {
 // ResourceManagerSvcRootPath returns the root path of resource manager service.
 // Path: /ms/{cluster_id}/resource_manager
 func ResourceManagerSvcRootPath(clusterID uint64) string {
-	return svcRootPath(clusterID, utils.ResourceManagerServiceName)
+	return SvcRootPath(clusterID, utils.ResourceManagerServiceName)
 }
 
 // SchedulingSvcRootPath returns the root path of scheduling service.
 // Path: /ms/{cluster_id}/scheduling
 func SchedulingSvcRootPath(clusterID uint64) string {
-	return svcRootPath(clusterID, utils.SchedulingServiceName)
+	return SvcRootPath(clusterID, utils.SchedulingServiceName)
 }
 
 // TSOSvcRootPath returns the root path of tso service.
 // Path: /ms/{cluster_id}/tso
 func TSOSvcRootPath(clusterID uint64) string {
-	return svcRootPath(clusterID, utils.TSOServiceName)
+	return SvcRootPath(clusterID, utils.TSOServiceName)
 }
 
-func svcRootPath(clusterID uint64, svcName string) string {
+func SvcRootPath(clusterID uint64, svcName string) string {
 	c := strconv.FormatUint(clusterID, 10)
 	return path.Join(utils.MicroserviceRootPath, c, svcName)
 }

pkg/tso/allocator_manager.go

@@ -101,13 +101,13 @@ func (info *DCLocationInfo) clone() DCLocationInfo {
 type ElectionMember interface {
 	// ID returns the unique ID in the election group. For example, it can be unique
 	// server id of a cluster or the unique keyspace group replica id of the election
-	// group comprised of the replicas of a keyspace group.
+	// group composed of the replicas of a keyspace group.
 	ID() uint64
-	// ID returns the unique name in the election group.
+	// Name returns the unique name in the election group.
 	Name() string
 	// MemberValue returns the member value.
 	MemberValue() string
-	// GetMember() returns the current member
+	// GetMember returns the current member
 	GetMember() interface{}
 	// Client returns the etcd client.
 	Client() *clientv3.Client

server/api/member.go

@@ -17,6 +17,7 @@ package api
 import (
 	"context"
 	"fmt"
+	"github.com/tikv/pd/pkg/mcs/discovery"
 	"net/http"
 	"strconv"
 
@@ -52,6 +53,28 @@ func newMemberHandler(svr *server.Server, rd *render.Render) *memberHandler {
 // @Failure  500  {string}  string  "PD server failed to proceed the request."
 // @Router   /members [get]
 func (h *memberHandler) GetMembers(w http.ResponseWriter, r *http.Request) {
+	if service := r.URL.Query().Get("service"); len(service) > 0 {
+		log.Info("get leader", zap.String("service", service))
+		resps, err := discovery.GetMembers(service, h.svr.GetClient())
+		if err != nil {
+			h.rd.JSON(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+		if resps == nil {
+			h.rd.JSON(w, http.StatusNotFound, fmt.Sprintf("no members for %s", service))
+			return
+		}
+
+		var apis []string
+		for _, resp := range resps.Responses {
+			for _, keyValue := range resp.GetResponseRange().GetKvs() {
+				apis = append(apis, string(keyValue.Value))
+			}
+		}
+		h.rd.JSON(w, http.StatusOK, apis)
+		return
+	}
+
 	members, err := getMembers(h.svr)
 	if err != nil {
 		h.rd.JSON(w, http.StatusInternalServerError, err.Error())
@@ -128,6 +151,16 @@ func (h *memberHandler) DeleteMemberByName(w http.ResponseWriter, r *http.Reques
 	// Get etcd ID by name.
 	var id uint64
 	name := mux.Vars(r)["name"]
+	if service := r.URL.Query().Get("service"); len(service) > 0 {
+		err := discovery.DeleteMemberByName(service, client)
+		if err != nil {
+			h.rd.JSON(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+		h.rd.JSON(w, http.StatusOK, fmt.Sprintf("removed, pd: %s", service))
+		return
+	}
+
 	listResp, err := etcdutil.ListEtcdMembers(client)
 	if err != nil {
 		h.rd.JSON(w, http.StatusInternalServerError, err.Error())
@@ -277,6 +310,20 @@ func newLeaderHandler(svr *server.Server, rd *render.Render) *leaderHandler {
 // @Success  200  {object}  pdpb.Member
 // @Router   /leader [get]
 func (h *leaderHandler) GetLeader(w http.ResponseWriter, r *http.Request) {
+	if service := r.URL.Query().Get("service"); len(service) > 0 {
+		log.Info("get leader", zap.String("service", service))
+		leader, _, err := discovery.GetMCSPrimary(service, h.svr.GetClient())
+		if err != nil {
+			h.rd.JSON(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+		if leader == nil {
+			h.rd.JSON(w, http.StatusNotFound, fmt.Sprintf("no leader for %s", service))
+			return
+		}
+		h.rd.JSON(w, http.StatusOK, leader)
+		return
+	}
 	h.rd.JSON(w, http.StatusOK, h.svr.GetLeader())
 }
 
@@ -304,7 +351,19 @@ func (h *leaderHandler) ResignLeader(w http.ResponseWriter, r *http.Request) {
 // @Failure  500  {string}  string  "PD server failed to proceed the request."
 // @Router   /leader/transfer/{nextLeader} [post]
 func (h *leaderHandler) TransferLeader(w http.ResponseWriter, r *http.Request) {
-	err := h.svr.GetMember().ResignEtcdLeader(h.svr.Context(), h.svr.Name(), mux.Vars(r)["next_leader"])
+	newLeader := mux.Vars(r)["next_leader"]
+	if service := r.URL.Query().Get("service"); len(service) > 0 {
+		log.Info("transfer leader", zap.String("service", service), zap.String("nextLeader", newLeader))
+		err := discovery.TransferPrimaryLeader(service, newLeader, h.svr.GetClient())
+		if err != nil {
+			h.rd.JSON(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+		h.rd.JSON(w, http.StatusOK, fmt.Sprintf("The transfer command is submitted. %s", newLeader))
+		return
+	}
+
+	err := h.svr.GetMember().ResignEtcdLeader(h.svr.Context(), h.svr.Name(), newLeader)
 	if err != nil {
 		h.rd.JSON(w, http.StatusInternalServerError, err.Error())
 		return