Event service for Yii2

Yii2 events provide a simple observer pattern implementation, allowing you to subscribe and listen for various events that occur within your application.

Install

Install via composer

composer require laxity7/yii2-event-service

How to use

1. Create an event class

It will be an any class that contains event data. You can also use the default Yii2 event class yii\base\Event.

For example:

namespace App\Events;

use yii\base\Event;

final readonly class PaymentEvent
{
    public function __construct(
        public float $amount,
        public string $currency,
        public string $description,
    ) {
    }
}

2. Create a listener class

It will be a class that contains a method handle or __invoke that will be called when the event is dispatched. The method must accept an event object as an argument.

For example:

namespace App\Events\listeners;

use App\Events\PaymentEvent;

final class PaymentListener
{
    //public function __invoke(PaymentEvent $event): void
    public function handle(PaymentEvent $event): void
    {
        Yii::info('Event: ' . get_class($event) . ' Trigger: ' . __METHOD__, __METHOD__);
    }
}

Note: You can also use a closure as a listener. The closure must accept an event object as an argument.

3. Subscribe to the event

Add the following code to your configuration file:

'components' => [
    'eventDispatcher' => [
         'class' => \Laxity7\Yii2\Components\EventServiceProvider::class,
         'listen' => [
             \App\Events\PaymentEvent::class => [
                 \App\Events\listeners\PaymentListener::class, // listener class
                 function (\App\Events\PaymentEvent $event) { // closure
                    Yii::info('Event: ' . get_class($event) . ' Trigger: ' . __METHOD__, __METHOD__);
                 },
             ],
         ],
    ],
],

4. Dispatch the event

use App\Events\PaymentEvent;
use Laxity7\Yii2\Components\Event;

$event = new PaymentEvent(100, 'USD', 'Payment for goods');
\Yii::$app->eventDispatcher->dispatch($event);
// or use the helper
Event::dispatch($event);