fix logger and redeem admin review findings

backend/internal/pkg/logger/logger.go

@@ -48,6 +48,7 @@ var (
 	atomicLevel   zap.AtomicLevel
 	initOptions   InitOptions
 	currentSink   atomic.Value // sinkState
+	currentClose  func()
 	stdLogUndo    func()
 	bootstrapOnce sync.Once
 )
@@ -72,16 +73,18 @@ func Init(options InitOptions) error {
 
 func initLocked(options InitOptions) error {
 	normalized := options.normalized()
-	zl, al, err := buildLogger(normalized)
+	zl, al, closeFn, err := buildLogger(normalized)
 	if err != nil {
 		return err
 	}
 
 	prev := global.Load()
+	prevClose := currentClose
 	global.Store(zl)
 	sugar.Store(zl.Sugar())
 	atomicLevel = al
 	initOptions = normalized
+	currentClose = closeFn
 
 	bridgeSlogLocked()
 	bridgeStdLogLocked()
@@ -89,6 +92,9 @@ func initLocked(options InitOptions) error {
 	if prev != nil {
 		_ = prev.Sync()
 	}
+	if prevClose != nil {
+		prevClose()
+	}
 	return nil
 }
 
@@ -205,6 +211,27 @@ func Sync() {
 	}
 }
 
+func Shutdown() {
+	mu.Lock()
+	defer mu.Unlock()
+
+	if stdLogUndo != nil {
+		stdLogUndo()
+		stdLogUndo = nil
+	}
+
+	if l := global.Load(); l != nil {
+		_ = l.Sync()
+	}
+	if currentClose != nil {
+		currentClose()
+		currentClose = nil
+	}
+
+	global.Store(nil)
+	sugar.Store(nil)
+}
+
 func bridgeStdLogLocked() {
 	if stdLogUndo != nil {
 		stdLogUndo()
@@ -238,7 +265,7 @@ func bridgeSlogLocked() {
 	slog.SetDefault(slog.New(newSlogZapHandler(base.Named("slog"))))
 }
 
-func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, error) {
+func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, func(), error) {
 	level, _ := parseLevel(options.Level)
 	atomic := zap.NewAtomicLevelAt(level)
 
@@ -265,6 +292,7 @@ func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, error) {
 
 	sinkCore := newSinkCore()
 	cores := make([]zapcore.Core, 0, 3)
+	var closers []io.Closer
 
 	if options.Output.ToStdout {
 		infoPriority := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
@@ -273,12 +301,12 @@ func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, error) {
 		errPriority := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
 			return lvl >= atomic.Level() && lvl >= zapcore.WarnLevel
 		})
-		cores = append(cores, zapcore.NewCore(enc, zapcore.Lock(os.Stdout), infoPriority))
-		cores = append(cores, zapcore.NewCore(enc, zapcore.Lock(os.Stderr), errPriority))
+		cores = append(cores, zapcore.NewCore(enc, stdStreamWriteSyncer(os.Stdout), infoPriority))
+		cores = append(cores, zapcore.NewCore(enc, stdStreamWriteSyncer(os.Stderr), errPriority))
 	}
 
 	if options.Output.ToFile {
-		fileCore, filePath, fileErr := buildFileCore(enc, atomic, options)
+		fileCore, filePath, fileCloser, fileErr := buildFileCore(enc, atomic, options)
 		if fileErr != nil {
 			_, _ = fmt.Fprintf(os.Stderr, "time=%s level=WARN msg=\"日志文件输出初始化失败，降级为仅标准输出\" path=%s err=%v\n",
 				time.Now().Format(time.RFC3339Nano),
@@ -287,11 +315,12 @@ func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, error) {
 			)
 		} else {
 			cores = append(cores, fileCore)
+			closers = append(closers, fileCloser)
 		}
 	}
 
 	if len(cores) == 0 {
-		cores = append(cores, zapcore.NewCore(enc, zapcore.Lock(os.Stdout), atomic))
+		cores = append(cores, zapcore.NewCore(enc, stdStreamWriteSyncer(os.Stdout), atomic))
 	}
 
 	core := zapcore.NewTee(cores...)
@@ -313,10 +342,14 @@ func buildLogger(options InitOptions) (*zap.Logger, zap.AtomicLevel, error) {
 		zap.String("service", options.ServiceName),
 		zap.String("env", options.Environment),
 	)
-	return logger, atomic, nil
+	return logger, atomic, func() {
+		for _, closer := range closers {
+			_ = closer.Close()
+		}
+	}, nil
 }
 
-func buildFileCore(enc zapcore.Encoder, atomic zap.AtomicLevel, options InitOptions) (zapcore.Core, string, error) {
+func buildFileCore(enc zapcore.Encoder, atomic zap.AtomicLevel, options InitOptions) (zapcore.Core, string, io.Closer, error) {
 	filePath := options.Output.FilePath
 	if strings.TrimSpace(filePath) == "" {
 		filePath = resolveLogFilePath("")
@@ -324,7 +357,7 @@ func buildFileCore(enc zapcore.Encoder, atomic zap.AtomicLevel, options InitOpti
 
 	dir := filepath.Dir(filePath)
 	if err := os.MkdirAll(dir, 0o755); err != nil {
-		return nil, filePath, err
+		return nil, filePath, nil, err
 	}
 	lj := &lumberjack.Logger{
 		Filename:   filePath,
@@ -334,7 +367,25 @@ func buildFileCore(enc zapcore.Encoder, atomic zap.AtomicLevel, options InitOpti
 		Compress:   options.Rotation.Compress,
 		LocalTime:  options.Rotation.LocalTime,
 	}
-	return zapcore.NewCore(enc, zapcore.AddSync(lj), atomic), filePath, nil
+	return zapcore.NewCore(enc, zapcore.AddSync(lj), atomic), filePath, lj, nil
+}
+
+type stdStreamSyncer struct {
+	file *os.File
+}
+
+func stdStreamWriteSyncer(file *os.File) zapcore.WriteSyncer {
+	return zapcore.Lock(&stdStreamSyncer{file: file})
+}
+
+func (s *stdStreamSyncer) Write(p []byte) (int, error) {
+	return s.file.Write(p)
+}
+
+func (s *stdStreamSyncer) Sync() error {
+	// Standard streams do not need fsync semantics, and on Windows a pipe-backed
+	// stdout/stderr can block indefinitely in FlushFileBuffers.
+	return nil
 }
 
 type sinkCore struct {

backend/internal/pkg/logger/logger_test.go

@@ -33,6 +33,7 @@ func TestInit_DualOutput(t *testing.T) {
 		_ = stdoutW.Close()
 		_ = stderrW.Close()
 	})
+	t.Cleanup(Shutdown)
 
 	err = Init(InitOptions{
 		Level:       "debug",
@@ -103,6 +104,7 @@ func TestInit_FileOutputFailureDowngrade(t *testing.T) {
 		_ = stderrR.Close()
 		_ = stderrW.Close()
 	})
+	t.Cleanup(Shutdown)
 
 	err = Init(InitOptions{
 		Level:  "info",
@@ -149,6 +151,7 @@ func TestInit_CallerShouldPointToCallsite(t *testing.T) {
 		_ = stdoutW.Close()
 		_ = stderrW.Close()
 	})
+	t.Cleanup(Shutdown)
 
 	if err := Init(InitOptions{
 		Level:       "info",

backend/internal/pkg/logger/options_test.go

@@ -95,7 +95,7 @@ func TestBuildFileCore_InvalidPathFallback(t *testing.T) {
 		EncodeLevel: zapcore.CapitalLevelEncoder,
 	}
 	encoder := zapcore.NewJSONEncoder(encoderCfg)
-	_, _, err := buildFileCore(encoder, zap.NewAtomicLevel(), opts)
+	_, _, _, err := buildFileCore(encoder, zap.NewAtomicLevel(), opts)
 	if err == nil {
 		t.Fatalf("buildFileCore() expected error for invalid path")
 	}

backend/internal/pkg/logger/stdlog_bridge_test.go

@@ -59,6 +59,7 @@ func TestStdLogBridgeRoutesLevels(t *testing.T) {
 		_ = stderrR.Close()
 		_ = stderrW.Close()
 	})
+	t.Cleanup(Shutdown)
 
 	if err := Init(InitOptions{
 		Level:       "debug",
@@ -121,6 +122,7 @@ func TestLegacyPrintfRoutesLevels(t *testing.T) {
 		_ = stderrR.Close()
 		_ = stderrW.Close()
 	})
+	t.Cleanup(Shutdown)
 
 	if err := Init(InitOptions{
 		Level:       "debug",