From 96fd5bda1b8814af6c2a82789be80aecc8353bd1 Mon Sep 17 00:00:00 2001
From: lhy1024 <admin@liudos.us>
Date: Wed, 23 Aug 2023 14:52:38 +0800
Subject: [PATCH] add more test

Signed-off-by: lhy1024 <admin@liudos.us>
---
 pkg/election/leadership.go      |  6 +++--
 pkg/election/leadership_test.go | 41 +++++++++++++++++++++++++++++++++
 pkg/utils/etcdutil/etcdutil.go  |  6 +++--
 3 files changed, 49 insertions(+), 4 deletions(-)

diff --git a/pkg/election/leadership.go b/pkg/election/leadership.go
index 90719678a64..255037fe26d 100644
--- a/pkg/election/leadership.go
+++ b/pkg/election/leadership.go
@@ -265,11 +265,13 @@ func (ls *Leadership) Watch(serverCtx context.Context, revision int64) {
 				continue
 			}
 			// We need to request progress to etcd to prevent etcd hold the watchChan,
-			// note: we must use the same ctx with watcher.
-			if err := watcher.RequestProgress(watcherCtx); err != nil {
+			// note: the ctx must be from watcherCtx, otherwise, the RequestProgress request cannot be sent properly.
+			ctx, cancel := context.WithTimeout(watcherCtx, etcdutil.DefaultDialTimeout)
+			if err := watcher.RequestProgress(ctx); err != nil {
 				log.Warn("failed to request progress in leader watch loop",
 					zap.String("leader-key", ls.leaderKey), zap.String("purpose", ls.purpose), zap.Error(err))
 			}
+			cancel()
 			// If no message comes from an etcd watchChan for WatchChTimeoutDuration,
 			// create a new one and need not to reset lastReceivedResponseTime.
 			if time.Since(lastReceivedResponseTime) >= etcdutil.WatchChTimeoutDuration {
diff --git a/pkg/election/leadership_test.go b/pkg/election/leadership_test.go
index d481cc79326..fd35c334f74 100644
--- a/pkg/election/leadership_test.go
+++ b/pkg/election/leadership_test.go
@@ -190,6 +190,47 @@ func TestExitWatch(t *testing.T) {
 			etcd2.Close()
 		}
 	})
+	// Case7: loss the quorum when the watch loop is running
+	checkExitWatch(t, leaderKey, func(server *embed.Etcd, client *clientv3.Client) func() {
+		tempStdoutFile, _ := os.CreateTemp("/tmp", "pd_tests")
+		defer os.Remove(tempStdoutFile.Name())
+		logCfg := &log.Config{}
+		logCfg.File.Filename = tempStdoutFile.Name()
+		logCfg.Level = "info"
+		lg, p, _ := log.InitLogger(logCfg)
+		log.ReplaceGlobals(lg, p)
+
+		cfg1 := server.Config()
+		cfg2 := etcdutil.NewTestSingleConfig(t)
+		cfg2.InitialCluster = cfg1.InitialCluster + fmt.Sprintf(",%s=%s", cfg2.Name, &cfg2.LPUrls[0])
+		cfg2.ClusterState = embed.ClusterStateFlagExisting
+		peerURL := cfg2.LPUrls[0].String()
+		addResp, err := etcdutil.AddEtcdMember(client, []string{peerURL})
+		re.NoError(err)
+		etcd2, err := embed.StartEtcd(cfg2)
+		re.NoError(err)
+		re.Equal(uint64(etcd2.Server.ID()), addResp.Member.ID)
+		<-etcd2.Server.ReadyNotify()
+
+		cfg3 := etcdutil.NewTestSingleConfig(t)
+		cfg3.InitialCluster = cfg2.InitialCluster + fmt.Sprintf(",%s=%s", cfg3.Name, &cfg3.LPUrls[0])
+		cfg3.ClusterState = embed.ClusterStateFlagExisting
+		peerURL = cfg3.LPUrls[0].String()
+		addResp, err = etcdutil.AddEtcdMember(client, []string{peerURL})
+		re.NoError(err)
+		etcd3, err := embed.StartEtcd(cfg3)
+		re.NoError(err)
+		re.Equal(uint64(etcd3.Server.ID()), addResp.Member.ID)
+		<-etcd3.Server.ReadyNotify()
+
+		resp2, err := client.MemberList(context.Background())
+		re.NoError(err)
+		re.Equal(3, len(resp2.Members))
+
+		etcd2.Server.HardStop()
+		etcd3.Server.HardStop()
+		return func() {}
+	})
 	re.NoError(failpoint.Disable("github.com/tikv/pd/pkg/election/fastTick"))
 	re.NoError(failpoint.Disable("github.com/tikv/pd/pkg/utils/etcdutil/fastTick"))
 }
diff --git a/pkg/utils/etcdutil/etcdutil.go b/pkg/utils/etcdutil/etcdutil.go
index e8c0b902316..fcfd2d459ff 100644
--- a/pkg/utils/etcdutil/etcdutil.go
+++ b/pkg/utils/etcdutil/etcdutil.go
@@ -726,11 +726,13 @@ func (lw *LoopWatcher) watch(ctx context.Context, revision int64) (nextRevision
 			continue
 		case <-ticker.C:
 			// We need to request progress to etcd to prevent etcd hold the watchChan,
-			// note: we need to use the same ctx with watcher.
-			if err := watcher.RequestProgress(watcherCtx); err != nil {
+			// note: the ctx must be from watcherCtx, otherwise, the RequestProgress request cannot be sent properly.
+			ctx, cancel := context.WithTimeout(watcherCtx, DefaultDialTimeout)
+			if err := watcher.RequestProgress(ctx); err != nil {
 				log.Warn("failed to request progress in leader watch loop",
 					zap.String("name", lw.name), zap.String("key", lw.key), zap.Error(err))
 			}
+			cancel()
 			// If no message comes from an etcd watchChan for WatchChTimeoutDuration,
 			// create a new one and need not to reset lastReceivedResponseTime.
 			if time.Since(lastReceivedResponseTime) >= WatchChTimeoutDuration {