Presenters in Rails

presenters_in_rails.md

Presenters in Rails

Without presenter

View

<h1>@post.title</h1>
<span>@post.publication_status</span>

Controller

class PostsController < ApplicationController
  def show
    @post = Post.find(params[:id])
  end
end

Model

class Post < ActiveRecord::Base
  def publication_status
    published_at || 'Draft'
  end
end

With presenter

View

<h1>@post.title</h1>
<span>@post.publication_status</span>

Controller

class PostsController < ApplicationController
  def show
    post = Post.find(params[:id])
    @post = PostPresenter.new(post)
  end
end

Models

class Post < ActiveRecord::Base
end

class PostPresenter
  def initialze(post)
    @post = post
  end
  def publication_status
    @post.published_at || 'Draft'
  end
end

With helper presenter

View

<% present(@post) do |post| %>
  <h1>post.title</h1>
  <span>post.publication_status</span>
<% end %>

Controller

class PostsController < ApplicationController
  def show
    @post = Post.find(params[:id])
  end
end

Models

class Post < ActiveRecord::Base
end

class PostPresenter
  def initialze(post)
    @post = post
  end
  def publication_status
    @post.published_at || 'Draft'
  end
end

Helper

module ApplicationHelper
  def present(model)
    klass = "#{model.class}Presenter".constantize
    presenter = klass.new(model)
    yield(presenter) if block_given?
  end
end

Source : http://nithinbekal.com/posts/rails-presenters/