TransportServiceFactoryInterface.php

<?php

declare (strict_types=1);
namespace Drupal\Core\Mailer;

use Symfony\Component\Mailer\Transport\TransportInterface;

/**
 * An interface defining mailer transport service factory implementations.
 *
 * The transport service factory is responsible to create a transport instance
 * according to the site configuration. The default service factory looks up the
 * `mailer_dsn` key from the `system.mail` config and returns an appropriate
 * transport implementation.
 *
 * Contrib and custom code may choose to replace or decorate the transport
 * service factory in order to provide a mailer transport instance which
 * requires more complex setup.
 */
interface TransportServiceFactoryInterface {
    
    /**
     * Creates and returns a configured mailer transport class.
     */
    public function createTransport() : TransportInterface;

}