func NewRollWriter()

in log/rollwriter/roll_writer.go [71:105]

• 28 lines of code
• 5 McCabe index (conditional complexity)

func NewRollWriter(filePath string, opt ...Option) (*RollWriter, error) {
	opts := &Options{
		MaxSize:    0,     // default no rolling by file size
		MaxAge:     0,     // default no scavenging on expired logs
		MaxBackups: 0,     // default no scavenging on redundant logs
		Compress:   false, // default no compressing
	}

	// opt has the highest priority and should overwrite the original one.
	for _, o := range opt {
		o(opts)
	}

	if filePath == "" {
		return nil, errors.New("invalid file path")
	}

	pattern, err := strftime.New(filePath + opts.TimeFormat)
	if err != nil {
		return nil, errors.New("invalid time pattern")
	}

	w := &RollWriter{
		filePath: filePath,
		opts:     opts,
		pattern:  pattern,
		currDir:  filepath.Dir(filePath),
	}

	if err := os.MkdirAll(w.currDir, 0755); err != nil {
		return nil, err
	}

	return w, nil
}