defer.md

Defer

The Defer system allows you to postpone the execution of heavy tasks until after the response has been sent to the user. This improves perceived performance.

Usage

You can use the Defer facade or the global defer() helper function:

use App\Notifications\Email\WelcomeEmail;
use Helpers\Data;
use System\Defer\Defer;
use Mail\Mail;

// Using the Facade
Defer::push(function () {
    $payload = Data::make(['name' => 'John', 'email' => 'john@example.com']);
    Mail::send(new WelcomeEmail($payload));
});

// Using the helper
defer(function () {
    // ...
});

Named Scopes

You can push tasks to specific named scopes to organize your background work:

use System\Defer\Defer;

// Using the Facade
Defer::name('emails')->push(function () {
    // ...
});

// Using the helper/service
deferrer()->name('emails')->push(function () {
    // ...
});

The Deferrer Service

The Defer facade is a static interface to the DeferrerInterface service. You can also access the service directly:

$deferrer = deferrer();

// Push to default queue
$deferrer->push(function() { ... });

// Push to named queue
$deferrer->name('images')->push(function() { ... });

How It Works

• Queueing: The closure is added to a queue in memory.
• Response: The application finishes processing the request and sends the response to the browser.
• Execution: Deferred callbacks are executed automatically after the response is sent (via KernelTerminateEvent) or after a CLI command finishes (via ConsoleTerminateEvent). This is handled by the ProcessDeferredTasksListener.

Requirements

• PHP-FPM: For fastcgi_finish_request() to work effectively.
• Container: The DeferrerInterface must be bound in the container.