Introduction:

In this tutorial, we will learn and explore Laravel 8 events and listeners. We will develop a small demo application in which we will send an email whenever a user is created. In this scenario, we can say user creation is an event, and the listener will send an email on listening to the event.

Register Event and Listener:

The first step is to register the event and the respective listener. For that, Laravel provides an EventServiceProvider.php file where you can define events and listeners.

The $listen property contains an array for registering all the events and listeners as key-value pairs. Define events and listeners as shown below.

protected $listen = [
   Registered::class => [
     SendEmailVerificationNotification::class,
   ],
   'App\Event\UserCreated' => [
     'App\Listeners\SendEmail'
   ]
];

Once you register the event and listener, run the below command to create the files for the respective event and listener.

php artisan event:generate

The above command will generate two files, namely:

• UserCreated in app/Events
• SendEmail in app/Listeners

Once done with the Laravel 8 events and listeners setup, now it’s time to get our hands on the logic part.

Define Event Logic:

In this section, we will define the action (event) on which we want the set of logic to be performed by the listener; in our demo app, the action is creating a user.

Open App\Events\UserCreated.php and use the below code to pass the actual email address as $email to the __construct method of the UserCreated class.

// App\Events\UserCreated.php

public $email;
 public function __construct($email)
 {
   $this->email = $email;
 }

The entire file will look like this.

namespace App\Event;

use Illuminate\Broadcasting\Channel;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Broadcasting\PresenceChannel;
use Illuminate\Broadcasting\PrivateChannel;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Queue\SerializesModels;

class UserCreated implements ShouldQueue
{
    use Dispatchable, InteractsWithSockets, SerializesModels;7i

    public $email;
    /**
     * Create a new event instance.
     *
     * @return void
     */
    public function __construct($email)
    {
        $this->email = $email;
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return \Illuminate\Broadcasting\Channel|array
     */
    public function broadcastOn()
    {
        return new PrivateChannel('channel-name');
    }
}

Here we inherit the ShouldQueue interface using class UserCreated implements ShouldQueue.It will automatically place the logic in the queue.

Define Listener Logic: handle() method:

Here, we will write actual logic for sending an email whenever the user is created. In App\Listeners\SendEmail.php, pass the UserCreated $event parameter to handle() method so that we can have a value from the event. The logic within the handle() method will be executed whenever the event is called.

public function handle(UserCreated $event)
 {
  print_r($event->email);
  //We can send a mail from here
  echo ".. From Listeners";
  exit;
 }

Dispatch Event:

After creating the event and listener, now it’s time to dispatch the event. It’s pretty straightforward; you just need to pass the event class object to the event() method.

// UserController.php

event (new UserCreated(“abc@gmail.com”));