fix

pkg/logging/daily.go

@@ -11,15 +11,38 @@ import (
 // file handle open for the active day and rotates on the first write after
 // midnight, matching the directory layout consumed by the log viewer.
 type DailyWriter struct {
-	mu   sync.Mutex
-	root string
-	name string
-	date string
-	file *os.File
+	mu           sync.Mutex
+	root         string
+	name         string
+	date         string
+	file         *os.File
+	retentionDay int
 }
 
-func NewDailyWriter(root, name string) *DailyWriter {
-	return &DailyWriter{root: root, name: name}
+func NewDailyWriter(root, name string, retentionDay int) *DailyWriter {
+	w := &DailyWriter{root: root, name: name, retentionDay: retentionDay}
+	w.removeExpired()
+	return w
+}
+
+func (w *DailyWriter) removeExpired() {
+	if w.retentionDay <= 0 {
+		return
+	}
+	entries, err := os.ReadDir(w.root)
+	if err != nil {
+		return
+	}
+	cutoff := time.Now().AddDate(0, 0, -w.retentionDay)
+	for _, entry := range entries {
+		if !entry.IsDir() {
+			continue
+		}
+		date, err := time.Parse("2006-01-02", entry.Name())
+		if err == nil && date.Before(cutoff) {
+			_ = os.RemoveAll(filepath.Join(w.root, entry.Name()))
+		}
+	}
 }
 
 func (w *DailyWriter) Write(value []byte) (int, error) {