Do not log config when the config is not changed

lib/config/proxy.go

@@ -5,6 +5,7 @@ package config
 
 import (
 	"bytes"
+	"maps"
 	"net"
 	"os"
 	"path/filepath"
@@ -168,6 +169,7 @@ func NewConfig() *Config {
 
 func (cfg *Config) Clone() *Config {
 	newCfg := *cfg
+	newCfg.Labels = maps.Clone(cfg.Labels)
 	return &newCfg
 }
 

lib/config/proxy_test.go

@@ -170,3 +170,12 @@ func TestGetIPPort(t *testing.T) {
 		require.Equal(t, cas.port, statusPort)
 	}
 }
+
+func TestCloneConfig(t *testing.T) {
+	cfg := testProxyConfig
+	cfg.Labels = map[string]string{"a": "b"}
+	clone := cfg.Clone()
+	require.Equal(t, cfg, *clone)
+	cfg.Labels["c"] = "d"
+	require.NotContains(t, clone.Labels, "c")
+}

pkg/manager/config/config.go

@@ -34,12 +34,7 @@ func (e *ConfigManager) reloadConfigFile(file string) error {
 // that are specified by users.
 func (e *ConfigManager) SetTOMLConfig(data []byte) (err error) {
 	e.sts.Lock()
-	defer func() {
-		if err == nil {
-			e.logger.Info("current config", zap.Any("cfg", e.sts.current))
-		}
-		e.sts.Unlock()
-	}()
+	defer e.sts.Unlock()
 
 	base := e.sts.current
 	if base == nil {
@@ -62,16 +57,22 @@ func (e *ConfigManager) SetTOMLConfig(data []byte) (err error) {
 	}
 
 	e.sts.current = base
+	originalData := e.sts.data
 	var buf bytes.Buffer
 	if err = toml.NewEncoder(&buf).Encode(base); err != nil {
 		return errors.WithStack(err)
 	}
-	e.sts.checksum = crc32.ChecksumIEEE(buf.Bytes())
-
-	for _, list := range e.sts.listeners {
-		list <- base.Clone()
+	newData := buf.Bytes()
+
+	// TiDB-Operator may set the same labels by the HTTP API periodically, don't notify the listeners every time.
+	if originalData == nil || !bytes.Equal(originalData, newData) {
+		e.sts.checksum = crc32.ChecksumIEEE(newData)
+		e.sts.data = newData
+		e.logger.Info("current config", zap.Any("cfg", e.sts.current))
+		for _, list := range e.sts.listeners {
+			list <- base.Clone()
+		}
 	}
-
 	return
 }
 

pkg/manager/config/config_test.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
@@ -142,7 +143,7 @@ func TestConfigRemove(t *testing.T) {
 	require.NoError(t, os.WriteFile(tmpcfg, []byte(`proxy.addr = "gg"`), 0644))
 
 	// check that re-watch still works
-	require.Eventually(t, func() bool { return cfgmgr.GetConfig().Proxy.Addr == "gg" }, 3*time.Second, 100*time.Millisecond)
+	require.Eventually(t, func() bool { return cfgmgr.GetConfig() != nil && cfgmgr.GetConfig().Proxy.Addr == "gg" }, 3*time.Second, 100*time.Millisecond)
 
 	// remove again but with a long sleep
 	require.NoError(t, os.Remove(tmpcfg))
@@ -298,13 +299,19 @@ func TestFilePath(t *testing.T) {
 }
 
 func TestChecksum(t *testing.T) {
-	cfgmgr, _, _ := testConfigManager(t, "", "")
+	cfgmgr, text, _ := testConfigManager(t, "", "")
+	require.Equal(t, 1, strings.Count(text.String(), "current config"))
 	c1 := cfgmgr.GetConfigChecksum()
 	require.NoError(t, cfgmgr.SetTOMLConfig([]byte(`proxy.addr = "gg"`)))
+	require.Equal(t, 2, strings.Count(text.String(), "current config"))
+	// same config, shouldn't log it again
+	require.NoError(t, cfgmgr.SetTOMLConfig([]byte(`proxy.addr = "gg"`)))
+	require.Equal(t, 2, strings.Count(text.String(), "current config"))
 	c2 := cfgmgr.GetConfigChecksum()
 	require.NoError(t, cfgmgr.SetTOMLConfig([]byte(`proxy.addr = "vv"`)))
 	c3 := cfgmgr.GetConfigChecksum()
 	require.NoError(t, cfgmgr.SetTOMLConfig([]byte(`proxy.addr="gg"`)))
+	require.Equal(t, 4, strings.Count(text.String(), "current config"))
 	c4 := cfgmgr.GetConfigChecksum()
 	require.Equal(t, c2, c4)
 	require.NotEqual(t, c1, c2)

pkg/manager/config/manager.go

@@ -42,11 +42,12 @@ type ConfigManager struct {
 	kv *btree.BTreeG[KVValue]
 
 	checkFileInterval time.Duration
-	fileContent       []byte
+	fileContent       []byte // used to compare whether the config file has changed
 	sts               struct {
 		sync.Mutex
 		listeners []chan<- *config.Config
 		current   *config.Config
+		data      []byte // used to strictly compare whether the config has changed
 		checksum  uint32 // checksum of the unmarshalled toml
 	}
 }

pkg/server/api/server.go

@@ -174,10 +174,8 @@ func (h *Server) attachLogger(c *gin.Context) {
 	switch {
 	case len(c.Errors) > 0:
 		h.lg.Warn(path, fields...)
-	case strings.Contains(path, "/debug"), strings.Contains(path, "/metrics"):
-		h.lg.Debug(path, fields...)
 	default:
-		h.lg.Info(path, fields...)
+		h.lg.Debug(path, fields...)
 	}
 }