Live Updates in Ruby on Rails with ActionCable Feature

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@santiago-rodrigSantiago Andrés Rodríguez Márquez

Complete-stack Developer, chess newbie, languages geek.

There are occasions when one as a Ruby on Rails developer desires to enforce a real-time characteristic, like a talk application, and after digging a little you discover a framework’s characteristic named ActionCable, sounds new and frightening, proper? Worry no longer, I will take a look at to give an explanation for it so simple as imaginable in order that on the finish of this newsletter you’ll be able to really feel at ease with the topic.

On the core, ActionCable makes use of the WebSocket connection protocol. The WebSocket protocol permits full-duplex connections between the shopper and the server to broadcast adjustments that happen in the server to the shopper as quickly because it occurs.

As a result of we’re truly busy and our best passion is the right way to enforce the real-time options to our Ruby on Rails application I will proceed with the stairs required to arrange ActionCable. The next steps think that you’re acquainted with Ruby on Rails and you might be the use of a model of it more than 5.2.

1. To your Gemfile, upload the redis gem and run package deal set up.

2. To your routes, mount the course the place WebSocket requests are going to be delivered. You’ll be able to do that with

mount ActionCable.server, at: '/cable'

, you guessed it, ‘/cable’ is the default trail.

3. Insert

<%= action_cable_meta_tag %>

on the head of your primary structure template.

4. Create a channel that can circulate from a given WebSocket identifier, for example, under is a code snippet of a document generated after operating

rails g channel messages

on the terminal.

# app/channels/messages_channel.rb
elegance MessagesChannel < ApplicationCable::Channel def subscribed stream_from 'messages' finish
5. Broadcast to the channel, you’ll be able to do that from every other a part of your application, it normally occurs in a task or a controller. The ultimate argument to the


manner is a hash that will probably be serialized as JSON and gained together with the shopper.

# app/controllers/messages_controller.rb
elegance MessagesController < ApplicationController def create # ... if ActionCable.server.broadcast( 'messages', frame: message.frame, writer: message.writer ) #... finish # ... finish
6. Ruby on Rails makes use of Redis to retailer and care for synced the messages despatched over the channel streams, when you have Redis put in in the neighborhood you’ll be able to get started the server at some port and specify the port to pay attention in your ActionCable configuration document.
# config/cable.yml
 adapter: redis
 url: redis://localhost:6478/1
# ...
7. After we generated the channel, a document named


used to be created beneath the channels folder within the listing protecting the javascript information (it’s other between Rails 5 and Rails 6), this document is the client-side of the WebSocket connection and is there the place the knowledge will probably be gained.

// Rails 5
// app/property/javascripts/channels/messages.js
App.messages = App.cable.subscriptions.create( 'MessagesChannel', ,
); // Rails 6
// app/javascript/channels/messages_channel.js
import shopper from './shopper'; shopper.subscriptions.create( 'MessagesChannel', ,

And that is the reason it! It might get sophisticated temporarily, however those are the fundamentals. In abstract, that is what it’s a must to do, first generate the channel, then specify from the place to circulate in your channel document (the Ruby one), after that broadcast to the channel on the specified circulate any place else in your application (a controller or a task), and in the end obtain the knowledge together with the shopper and show it the use of JavaScript DOM manipulation.

I am a Complete-stack Ruby on Rails developer with many tasks in the pocket that put into apply what I write about, if you wish to achieve out to me right here you may have my e mail and my LinkedIn profile, simply in case this is my GitHub profile too.

Satisfied coding!


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