增加日志系统

backend/internal/logging/daily_writer.go

@@ -0,0 +1,71 @@
+package logging
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+)
+
+type dailyWriter struct {
+	mu       sync.Mutex
+	dir      string
+	prefix   string
+	location *time.Location
+	day      string
+	file     *os.File
+}
+
+func newDailyWriter(dir string, prefix string, location *time.Location) *dailyWriter {
+	return &dailyWriter{
+		dir:      dir,
+		prefix:   prefix,
+		location: location,
+	}
+}
+
+func (w *dailyWriter) Write(p []byte) (int, error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if err := w.rotateIfNeeded(time.Now().In(w.location)); err != nil {
+		return 0, err
+	}
+	return w.file.Write(p)
+}
+
+func (w *dailyWriter) Sync() error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if w.file == nil {
+		return nil
+	}
+	return w.file.Sync()
+}
+
+func (w *dailyWriter) rotateIfNeeded(now time.Time) error {
+	day := now.Format("2006-01-02")
+	if w.file != nil && w.day == day {
+		return nil
+	}
+
+	if err := os.MkdirAll(w.dir, 0o755); err != nil {
+		return err
+	}
+
+	if w.file != nil {
+		_ = w.file.Close()
+		w.file = nil
+	}
+
+	path := filepath.Join(w.dir, fmt.Sprintf("%s-%s.log", w.prefix, day))
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
+	if err != nil {
+		return err
+	}
+	w.file = file
+	w.day = day
+	return nil
+}