class Ougai::Formatters::Customizable

def default_msg_format(color_config)
  proc do |severity, datetime, _progname, data|
    msg = data.delete(:msg)
    severity  = color_config.color(:severity, severity, severity)
    datetime  = color_config.color(:datetime, datetime, severity)
    msg       = color_config.color(:msg, msg, severity)
    "[#{datetime}] #{severity}: #{msg}"
  end
end