Have you ever wanted to refactor something into the model ( skinny controller, fat model ) but didn’t know how to deal with your flash notifications?

Here’s a solution that I cooked up:

module FlashExceptions
  class FlashException < StandardError; end
  class FlashError < FlashException; end
  class FlashNotice < FlashException; end
  class FlashSuccess < FlashException; end
end

###########################################

class Model < ActiveRecord::Base
  include FlashExceptions

  def self.do_something! opts = {}
    raise FlashError, opts[:error] if opts[:error]
    raise FlashNotice, opts[:notice] if opts[:notice]
    raise FlashSuccess, opts[:success] if opts[:success]
  end

end

###########################################

class Controller < ApplicationController

  def action
    Model.do_something! :error => 'oops!', :notice => 'ahem.', :success => 'yay!'
  rescue FlashException => e
    flash[ e.class.underscore.split('_').last ] = e.message
  end

end