blog_app/app/Providers/EventServiceProvider.php

<?php

namespace App\Providers;

use App\Events\PostPublished;
use App\Events\PostScheduled;
use App\Events\CommentCreated;
use App\Events\CommentApproved;
use App\Listeners\SendPostPublishedNotification;
use App\Listeners\LogPostScheduled;
use App\Listeners\NotifyAdminAboutComment;
use App\Listeners\NotifyCommentAuthor;
use Illuminate\Foundation\Support\Providers\EventServiceProvider as ServiceProvider;

class EventServiceProvider extends ServiceProvider
{
    protected $listen = [
        PostPublished::class => [
            SendPostPublishedNotification::class,
        ],
        PostScheduled::class => [
            LogPostScheduled::class,
        ],
        CommentCreated::class => [
            NotifyAdminAboutComment::class,
        ],
        CommentApproved::class => [
            NotifyCommentAuthor::class,
        ],
    ];
}