refactor: move accesslog to logging/accesslog

internal/logging/accesslog/multi_writer.go

@@ -0,0 +1,46 @@
+package accesslog
+
+import "strings"
+
+type MultiWriter struct {
+	writers []AccessLogIO
+}
+
+func NewMultiWriter(writers ...AccessLogIO) AccessLogIO {
+	if len(writers) == 0 {
+		return nil
+	}
+	if len(writers) == 1 {
+		return writers[0]
+	}
+	return &MultiWriter{
+		writers: writers,
+	}
+}
+
+func (w *MultiWriter) Write(p []byte) (n int, err error) {
+	for _, writer := range w.writers {
+		writer.Write(p)
+	}
+	return len(p), nil
+}
+
+func (w *MultiWriter) Lock() {
+	for _, writer := range w.writers {
+		writer.Lock()
+	}
+}
+
+func (w *MultiWriter) Unlock() {
+	for _, writer := range w.writers {
+		writer.Unlock()
+	}
+}
+
+func (w *MultiWriter) Name() string {
+	names := make([]string, len(w.writers))
+	for i, writer := range w.writers {
+		names[i] = writer.Name()
+	}
+	return strings.Join(names, ", ")
+}