Automatic mapping of event to controller actions

00-register_interest_controller.rb

class RegisterInterestController < ApplicationController
  skip_before_filter :ensure_logged_in

  def create
    @interest_form = RegisterInterest::InterestForm.new(form_params)
    register_interest = RegisterInterest.new
    register_interest.subscribe(EventResponser.new(self))
    register_interest.with_form(@interest_form)
  end

  private

  def form_params
    params[:interest_form]
  end
end

event_responser.rb

# maps events to controller actions, for example if the publisher (RegisterInterest) broadcast an 
# "register_interest_successful" event then the "success" action would be rendered.

class EventResponser
    def initialize(controller)
      @controller = controller
    end

    def respond_to?(method_name)
      %w(success failed).any? { |word| method_name.to_s.include?(word) } || super
    end

    def method_missing(method_name, *args, &block)
      if method_name.to_s.downcase.include?('success')
        @controller.render(:action => :success)
      elsif method_name.to_s.downcase.include?('failed')
        @controller.render(:action => :failed)
      else
        super
      end
    end
  end