The number 2 is odd or even

Sample text of the article

How the pieces fit

A model change fires an event, the event broadcasts on a channel, and every subscribed client receives it instantly.

graph LR;
    A[Model updated] --> B[Broadcast event];
    B --> C[WebSocket server];
    C --> D[Browser client 1];
    C --> E[Browser client 2];

Broadcasting an event

Mark the event with ShouldBroadcast and Laravel queues it for delivery:

phpapp/Events/OrderShipped.php

<?php

namespace App\Events;

use Illuminate\Broadcasting\Channel;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

class OrderShipped implements ShouldBroadcast
{
    public function __construct(public int $orderId) {}

    public function broadcastOn(): Channel
    {
        return new Channel('orders');
    }
}

Listening on the client

Echo subscribes to the channel and runs a callback for each event:

tsresources/js/orders.ts

import Echo from 'laravel-echo';

window.Echo.channel('orders').listen('OrderShipped', (event) => {
    console.log(`Order ${event.orderId} shipped`);
});

Keep channels authorized

Private channels run through an auth callback, so only the right user receives sensitive updates. Public channels like the one above are fine for non-sensitive broadcasts.

Reference configuration

A full broadcasting config, including the queue connection, is worth keeping handy:

	class HelloWorld
	def initialize(name)
	@name = name.capitalize
	end
	def sayHi
	puts "Hello #{@name}!"
	end
	end

	hello = HelloWorld.new("World")
	hello.sayHi

view raw hello_world.rb hosted with ❤ by GitHub

Start with one channel and a single event, confirm the round trip works, then grow from there.