Events

Webrium ships a simple publish/subscribe system, useful for decoupling parts of your application — for example, sending a welcome email when a user registers, without coupling the registration logic directly to the mailer.

Registering Listeners

Use Event::on() to register a listener that runs every time an event is emitted:

use Webrium\Event;

Event::on('user.registered', function ($user) {
    // send welcome email, log activity, etc.
});

Emitting Events

Event::emit('user.registered', $user);

Any number of arguments can be passed to emit() — they are forwarded to every listener in the same order:

Event::emit('order.placed', $order, $user);

Event::on('order.placed', function ($order, $user) {
    // ...
});

One-Time Listeners

Event::once() registers a listener that runs only the first time the event is emitted, and is then automatically removed:

Event::once('app.booted', function () {
    // runs only on the first boot
});

Event::emit('app.booted'); // listener runs
Event::emit('app.booted'); // listener does NOT run again

This is useful for one-time setup tasks, initialization hooks, or guarding against duplicate processing. One-shot listeners are de-queued before they run, so even if the callback re-emits the same event, it will not fire itself a second time.

Checking for Listeners

if (Event::has('user.registered')) {
    // at least one listener (persistent or one-time) is registered
}

Removing Listeners

Event::remove('user.registered');

This removes all listeners — both persistent and one-time — registered for the event.

Example: Decoupling Registration Logic

// In a service provider or bootstrap file:
use Webrium\Event;

Event::on('user.registered', function ($user) {
    Mailer::send($user->email, 'welcome', ['name' => $user->name]);
});

Event::on('user.registered', function ($user) {
    Log::info("New user registered: {$user->email}");
});

// In the controller:
namespace App\Controllers;

use Webrium\Event;

class AuthController
{
    public function register()
    {
        $user = User::create(input());

        Event::emit('user.registered', $user);

        return ['status' => 'registered'];
    }
}

The controller does not need to know about email or logging — it just announces that registration happened.

Framework Events

Some framework subsystems emit events of their own that your application can listen for. The most useful one is error, emitted by the error handler every time an error is captured:

Event::on('error', function ($data) {
    // $data: ['message', 'line', 'file', 'type', 'is_fatal']
});