# File lib/lumberjack/device/date_rolling_log_file.rb, line 28
      def archive_file_suffix
        case @roll_period
        when :weekly
          "#{@file_date.strftime('week-of-%Y-%m-%d')}"
        when :monthly
          "#{@file_date.strftime('%Y-%m')}"
        else
          "#{@file_date.strftime('%Y-%m-%d')}"
        end
      end