优化结构

internal/logging/daily.go

@@ -50,6 +50,9 @@ func (w *DailyWriter) Write(value []byte) (int, error) {
 	defer w.mu.Unlock()
 	date := time.Now().Format("2006-01-02")
 	if w.file == nil || w.date != date {
+		// Retention is enforced again when a long-lived writer rolls to a new day.
+		// Running this only on rotation avoids a directory scan for every write.
+		w.removeExpired()
 		if w.file != nil {
 			_ = w.file.Close()
 		}

internal/logging/daily_test.go

@@ -0,0 +1,26 @@
+package logging
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestDailyWriterCleansExpiredDirectoriesOnRotation(t *testing.T) {
+	root := t.TempDir()
+	writer := NewDailyWriter(root, "application.log", 1)
+	oldDate := time.Now().AddDate(0, 0, -3).Format("2006-01-02")
+	oldDir := filepath.Join(root, oldDate)
+	if err := os.MkdirAll(oldDir, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	writer.date = "2000-01-01"
+	if _, err := writer.Write([]byte("rotated\n")); err != nil {
+		t.Fatal(err)
+	}
+	_ = writer.Close()
+	if _, err := os.Stat(oldDir); !os.IsNotExist(err) {
+		t.Fatalf("expired directory still exists: err=%v", err)
+	}
+}

internal/logging/zap.go

@@ -460,7 +460,7 @@ func safeModuleName(value string) string {
 	}, value)
 }
 
-// NewZapLogger adapts a Zap core to the slog logger used by Kratos v3.
+// newZapHandler adapts a Zap core to the slog handler used by Kratos v3.
 // The file layout remains compatible with the administration log viewer.
 func newZapHandler(root, filename string, options Options, errorSink *errorSinkState) (slog.Handler, func()) {
 	file := NewDailyWriter(root, filename, options.RetentionDay)
@@ -538,8 +538,3 @@ func NewReloadableZapLogger(root, filename string, options Options, attrs ...any
 	logger := kratoslog.NewLogger(handler, kratoslog.WithExtractor(tracing.TraceAttrs)).With(attrs...)
 	return logger, control
 }
-
-func NewZapLogger(root, filename string, options Options, attrs ...any) (*slog.Logger, func()) {
-	logger, control := NewReloadableZapLogger(root, filename, options, attrs...)
-	return logger, control.Close
-}