log: support change the level of etcd for debugging

dm/master/config.go

@@ -439,17 +439,22 @@ func parseURLs(s string) ([]url.URL, error) {
 	return urls, nil
 }
 
-func genEmbedEtcdConfigWithLogger() *embed.Config {
+func genEmbedEtcdConfigWithLogger(logLevel string) *embed.Config {
 	cfg := embed.NewConfig()
 	cfg.EnableGRPCGateway = true // enable gRPC gateway for the internal etcd.
 
 	// use zap as the logger for embed etcd
 	// NOTE: `genEmbedEtcdConfig` can only be called after logger initialized.
 	// NOTE: if using zap logger for etcd, must build it before any concurrent gRPC calls,
 	// otherwise, DATA RACE occur in NewZapCoreLoggerBuilder and gRPC.
-	// NOTE: we can only increase the log level for the clone logger but not decrease.
-	logger := log.L().WithFields(zap.String("component", "embed etcd")).WithOptions(zap.IncreaseLevel(zap.ErrorLevel))
-	cfg.ZapLoggerBuilder = embed.NewZapCoreLoggerBuilder(logger, logger.Core(), log.Props().Syncer) // use global app props.
+	logger := log.L().WithFields(zap.String("component", "embed etcd"))
+	// if logLevel is info, set etcd log level to WARN to reduce log
+	if strings.ToLower(logLevel) == "info" {
+		log.L().Info("Set log level of etcd to `warn`, if you want to log more message about etcd, change log-level to `debug` in master configuration file")
+		logger.Logger = logger.WithOptions(zap.IncreaseLevel(zap.WarnLevel))
+	}
+
+	cfg.ZapLoggerBuilder = embed.NewZapCoreLoggerBuilder(logger.Logger, logger.Core(), log.Props().Syncer) // use global app props.
 	cfg.Logger = "zap"
 
 	// TODO: we run ZapLoggerBuilder to set SetLoggerV2 before we do some etcd operations

dm/master/etcd_test.go

@@ -55,7 +55,7 @@ func (t *testEtcdSuite) TestStartEtcdFail(c *check.C) {
 	c.Assert(cfgCluster.adjust(), check.IsNil)
 
 	// start an etcd cluster
-	cfgClusterEtcd := genEmbedEtcdConfigWithLogger()
+	cfgClusterEtcd := genEmbedEtcdConfigWithLogger("info")
 	cfgClusterEtcd, err := cfgCluster.genEmbedEtcdConfig(cfgClusterEtcd)
 	c.Assert(err, check.IsNil)
 	e, err := startEtcd(cfgClusterEtcd, nil, nil, 3*time.Second)
@@ -71,7 +71,7 @@ func (t *testEtcdSuite) TestPrepareJoinEtcd(c *check.C) {
 	cfgCluster.AdvertiseAddr = tempurl.Alloc()[len("http://"):]
 	cfgCluster.PeerUrls = tempurl.Alloc()
 	c.Assert(cfgCluster.adjust(), check.IsNil)
-	cfgClusterEtcd := genEmbedEtcdConfigWithLogger()
+	cfgClusterEtcd := genEmbedEtcdConfigWithLogger("info")
 	cfgClusterEtcd, err := cfgCluster.genEmbedEtcdConfig(cfgClusterEtcd)
 	c.Assert(err, check.IsNil)
 
@@ -178,7 +178,7 @@ func (t *testEtcdSuite) TestPrepareJoinEtcd(c *check.C) {
 	c.Assert(err, check.ErrorMatches, ".*fail to join embed etcd: there is a member that has not joined successfully, continue the join or remove it.*")
 
 	// start the joining etcd
-	cfgAfterEtcd := genEmbedEtcdConfigWithLogger()
+	cfgAfterEtcd := genEmbedEtcdConfigWithLogger("info")
 	cfgAfterEtcd, err = cfgAfter.genEmbedEtcdConfig(cfgAfterEtcd)
 	c.Assert(err, check.IsNil)
 	e2, err := startEtcd(cfgAfterEtcd, nil, nil, etcdStartTimeout)

dm/master/server.go

@@ -140,7 +140,7 @@ func NewServer(cfg *Config) *Server {
 
 // Start starts to serving
 func (s *Server) Start(ctx context.Context) (err error) {
-	etcdCfg := genEmbedEtcdConfigWithLogger()
+	etcdCfg := genEmbedEtcdConfigWithLogger(s.cfg.LogLevel)
 	// prepare config to join an existing cluster
 	err = prepareJoinEtcd(s.cfg)
 	if err != nil {