php 44 lines · 6 steps

How event subscribers group listeners in Laravel

A single subscriber class handles multiple order events by mapping each event to a handler method.

Explained by highlit
Laravel Intermediate event-driven subscribers queues notifications decoupling
1<?php
2 
3namespace App\Listeners;
4 
5use App\Events\OrderPlaced;
6use App\Events\OrderRefunded;
7use App\Jobs\GenerateInvoice;
8use App\Notifications\OrderConfirmation;
9use Illuminate\Events\Dispatcher;
10use Illuminate\Support\Facades\Log;
11 
12class OrderEventSubscriber
13{
14 public function handleOrderPlaced(OrderPlaced $event): void
15 {
16 $order = $event->order;
17 
18 $order->customer->notify(new OrderConfirmation($order));
19 GenerateInvoice::dispatch($order)->onQueue('billing');
20 
21 $order->warehouse->reserveStock($order->lineItems);
22 }
23 
24 public function handleOrderRefunded(OrderRefunded $event): void
25 {
26 $order = $event->order;
27 
28 $order->payment->issueRefund($event->amount);
29 $order->warehouse->releaseStock($order->lineItems);
30 
31 Log::channel('finance')->info('Order refunded', [
32 'order_id' => $order->id,
33 'amount' => $event->amount->format(),
34 ]);
35 }
36 
37 public function subscribe(Dispatcher $events): array
38 {
39 return [
40 OrderPlaced::class => 'handleOrderPlaced',
41 OrderRefunded::class => 'handleOrderRefunded',
42 ];
43 }
44}
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1A subscriber class consolidates related event handlers so one bounded context lives in one place.
  2. 2Dispatching jobs to a named queue keeps slow side effects off the request path.
  3. 3The subscribe method's array is the contract that wires events to methods, keeping registration declarative.

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