Ruby on Rails Q & A


How to use ActionCable in Rails?

ActionCable is a framework in Rails that seamlessly integrates WebSockets into your application, allowing for real-time features like chat, notifications, and live updates. By using WebSockets, Rails can push content to the connected users as it becomes available, ensuring a more interactive and dynamic user experience. Let’s walk through the basics of integrating ActionCable:


  1. Setup: If you generated your Rails application with Rails 5 or later, ActionCable should already be set up. If not, you’ll need to add `gem ‘actioncable’` to your Gemfile and run `bundle install`.


  1. Channels: In ActionCable, communication is organized around channels. A channel is like a controller, but for WebSocket communication. You can generate a new channel using:



   rails generate channel MyChannel



  1. Server-Side Logic: Inside your generated channel (e.g., `app/channels/my_channel.rb`), you’ll define methods that handle different WebSocket events:



   class MyChannel < ApplicationCable::Channel

     def subscribed

       stream_from "my_channel"


     def receive(data)

       # Handle data sent from the client-side





  1. Client-Side Logic: Corresponding JavaScript code will be generated in `app/javascript/channels/my_channel.js`. This is where you can define client-side behavior for when data is received from the server:



   consumer.subscriptions.create("MyChannel", {

     received(data) {

       // Handle data received from the server





  1. Broadcasting: To send data from the server to clients, you can use broadcasting. From anywhere in your Rails app, you can broadcast to a channel:



   ActionCable.server.broadcast('my_channel', message: 'Hello World!')



  1. Deployment Considerations: For deploying apps using ActionCable, you’d typically need a server setup that supports WebSocket, like Puma. Additionally, if you’re deploying on platforms like Heroku, you might need to use an add-on like Redis to manage the WebSocket connections.


ActionCable offers a built-in solution in Rails to leverage WebSockets, making real-time features more accessible for developers. By following the conventions and patterns set out by the framework, you can quickly add dynamic, real-time elements to enhance your application’s user experience. However, always ensure you understand the scalability and deployment implications when working with real-time features.

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Senior Software Engineer with a focus on remote work. Proficient in Ruby on Rails. Expertise spans y6ears in Ruby on Rails development, contributing to B2C financial solutions and data engineering.