internal/log/RotatingFileOptions.go: adding implementation for the functional option pattern.

internal/log/RotatingFileOptions.go

@@ -0,0 +1,17 @@
+package log
+
+import "time"
+
+type RotatingFileOption func(*RotatingFile)
+
+func WithMaxSize(value int64) RotatingFileOption {
+	return func(f *RotatingFile) {
+		f.maxSize = value
+	}
+}
+
+func WithMaxAge(value time.Duration) RotatingFileOption {
+	return func(f *RotatingFile) {
+		f.maxAge = value
+	}
+}