Focused Controller - Aiming for "real OOP" in Rails controllers

While Rails controllers are Ruby classes and have some OOP support as a result, the lack of true encapsulation and awkward before_filter-based sharing of code between actions leave some OOP die hards disappointed. Jon Leighton’s Focused Controller is an early stage project that takes a different approach. Controllers are Ruby modules and actions are classes classes that inherit ultimately from ApplicationController:

module PostsController
  # Action is a common superclass for all the actions
  # inside `PostsController`.
  class Action < ApplicationController
    include FocusedController::Mixin
  end

  class Index < Action
    def run
      # Your code here.
    end

    # No instance variables are shared with the view. Instead,
    # public methods are defined.
    def posts
      @posts ||= Post.all
    end

    # To prevent yourself having to write `controller.posts`
    # in the view, you can declare the method as a helper
    # method which means that calling `posts` automatically
    # delegates to the controller.
    helper_method :posts
  end

  # Actions do not need to declare a `run` method - the default
  # implementation inherited from `FocusedController::Mixin` is an
  # empty method.
  class Show < Action
    def post
      @post ||= Post.find params[:id]
    end
    helper_method :post
  end
end

Since routes need to be modified to point to this new convention of Controller::Action#run, a helper is provided for your routes file that supports the usual syntax:

focused_controller_routes do
  resources :posts
end

Jon is looking for feedback so check out the README for advanced usage, especially on how to test this new style of controller.