Creating the Rails API

Setting up the JSON api

If we want to persist our changes, the first thing we'll need to do is have the index page display what's in the database rather than using our hard coded array.

Let's make sure that our index action is set up to return JSON. We need to add the appropriate routes back into Rails, but we don't want to trample on Backbone for non-json requests. Unfortunately, there's no good way to tell Rails to only use a route for JSON requests (we can come close with constraints, but they ignore the Accept header). One option would be to prefix all of our API routes with /api, but for now let's rely on the fact that we only need index, update, and create, none of which conflict with Backbone.

• In the routes file add a call to resources

  resources :notes, only: [:index, :create, :update, :destroy]
  

• In order to keep Rails and Backbone from conflicting we also want to route any request to our notes#index action

  get '*any' => 'notes#index'
  

• Next we want to build out our Notes Rails controller to connect with our Backbone application

  class NotesController < ApplicationController
    helper_method :notes, :note
    respond_to :json, only: [:index, :create, :update, :destroy]
    respond_to :html, only: [:index]
  
    def index
      respond_with notes
    end
  
    def create
      note = Note.create(note_params)
      respond_with note
    end
  
    def update
      note.update_attributes(note_params)
      respond_with note
    end
  
    def destroy
      respond_with note.destroy
    end
  
    private
  
    def note_params
      params.permit(:title, :content)
    end
  
    def notes
      @_notes ||= Note.all
    end
  
    def note
      @_note ||= notes.find(params[:id])
    end
  end
  

• Commit!