Moving to an API based architecture

As of now the Rails view is building the list of "Tasks" and the server is responding with the HTML.

Now we will switch to the API style where the server will primarily send data as JSON API and the client will build the HTML. This is different from the "pure API" style that we discussed in the last chapter. Here the frontend code and the backend code are in the same repository.

Deleting Rails views

As we will be sending JSON responses from controllers we don't need this tasks/index.html.erb file. We can remove this file like so:

1rm app/views/tasks/index.html.erb
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Sending JSON response from the controllers

Let's open app/controllers/tasks_controller.rb and let's change the index action.

Since tasks in no longer required in its corresponding view file, we can remove the @ sign as it needn't be an instance variable:

1class TasksController < ApplicationController
2  def index
3    tasks = Task.all
4    render status: :ok, json: { tasks: }
5  end
6end
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In Ruby 3.1.2, we can omit the values in hash literals and keyword arguments.

For example, { x: , y: } is a syntax sugar of { x: x, y: y }. Similarly foo( x:, y: ) is a syntax sugar of foo( x: x, y: y ).

So, the json response in the above mentioned index action is equivalent to { tasks: tasks }.

For more details please refer to this issue from the Ruby org.

If we open new task page by going to the URL http://localhost:3000/tasks we will be getting the response in the JSON format.

Configuring React for API based architecture

Let's create a new controller called Home:

1bundle exec rails generate controller Home
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It will generate the following files:

1Running via Spring preloader in process 8810
2      create  app/controllers/home_controller.rb
3      invoke  erb
4      create    app/views/home
5      invoke  test_unit
6      create    test/controllers/home_controller_test.rb
7      invoke  helper
8      create    app/helpers/home_helper.rb
9      invoke    test_unit
10      invoke  assets
11      invoke    scss
12      create      app/assets/stylesheets/home.scss
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Now let's create an index action:

1class HomeController < ApplicationController
2  def index
3    render
4  end
5end
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We have already created our entry point App.jsx, in the chapter for setting up react environment.

App.jsx will act as the single entry point to the React client and react-router will be used for routing in the React side.

We will be serving App.jsx when the home#index action is called.

So now, we need to create a view file for home#index, if it doesn't exist already:

1touch app/views/home/index.html.erb
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Add the following line in to app/views/home/index.html.erb:

1<%= react_component 'App' %>
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Updating Rails routes

Open config/routes.rb and add following lines:

1Rails.application.routes.draw do
2  resources :tasks, only: :index
3
4  root "home#index"
5  get '*path', to: 'home#index', via: :all
6end
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Now visit http://localhost:3000/ and this time we should get message Home.

Now let's commit these changes:

1git add -A
2git commit -m "Added API based architecture"
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