Events, listeners and notifications

Domain events decoupling a workflow, model observers, queued listeners, and notifications across mail, database and broadcast channels.

Events and listeners

class OrderPlaced
{
    use Dispatchable, SerializesModels;
    public function __construct(public Order $order) {}
}

class ReserveStock implements ShouldQueue
{
    public function handle(OrderPlaced $event): void
    {
        $event->order->items->each(fn ($item) => $item->reserve());
    }
}

// dispatch after the transaction commits
DB::transaction(function () use ($order) {
    $order->save();
    OrderPlaced::dispatch($order)->afterCommit();
});

• Queued listeners run outside the request, so dispatch afterCommit() - otherwise a listener can act on a row that a later rollback erases.
• Auto-discovery scans app/Listeners; register explicit mappings in AppServiceProvider when the wiring is not obvious.
• An event with several listeners is a fan-out, not a workflow. If the steps must be ordered, use a chain of jobs instead.

Observers

class BookObserver
{
    public function creating(Book $book): void
    {
        $book->slug ??= Str::slug($book->title);
        $book->created_by ??= auth()->id();
    }

    public function updated(Book $book): void
    {
        if ($book->wasChanged('status')) {
            Cache::forget("book:{$book->id}");
        }
    }

    public function deleted(Book $book): void
    {
        $book->cover?->delete();
    }
}

#[ObservedBy(BookObserver::class)]
class Book extends Model {}

// bulk updates bypass observers entirely
Book::where('status', 'draft')->update(['status' => 'archived']);

Notifications and broadcasts

class OrderShipped extends Notification implements ShouldQueue
{
    public function __construct(public Order $order) {}

    public function via(object $notifiable): array
    {
        return $notifiable->wantsSms()
            ? ['mail', 'database', 'vonage']
            : ['mail', 'database'];
    }

    public function toMail(object $notifiable): MailMessage
    {
        return (new MailMessage)
            ->subject('Your order shipped')
            ->line("Tracking number: {$this->order->tracking}")
            ->action('Track it', url("/orders/{$this->order->id}"));
    }

    public function toDatabase(object $notifiable): array
    {
        return ['order_id' => $this->order->id, 'status' => 'shipped'];
    }
}

$user->notify(new OrderShipped($order));
Notification::send($users, new OrderShipped($order));

• The database channel needs the notifications table: php artisan make:notifications-table then migrate.
• Broadcast channels need driver configuration plus authentication on your private channels; publish to PrivateChannel and authorize it in routes/channels.php.
• Queue notifications (ShouldQueue) or the mail driver becomes part of the request latency.

FAQ

Related

Queues, jobs and scheduled tasks The service container, providers and facades

Last refreshed 2026-09-18.