Communications Framework

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Sending a notification to a mapped object is the most common use-case and is more convenient for developers. However, there may be advanced cases where you want to send a notification directly to a recipient. The notifier service can be used in this scenario.

Notifier service ​

The notifier service can be found at service ID notifier or \Symfony\Component\Notifier\NotifierInterface. Preferably, notifier is set up with autowiring rather than using the universal \Drupal locator class.

Autowiring ​

The notifier service is autowired with \Symfony\Component\Notifier\NotifierInterface.

Service example ​

yaml
services:
  _defaults:
    autowire: true
    
  my_service:
    class: Drupal\my_module\MyService
php
namespace Drupal\my_module;

final class MyService {

  public function __construct(
    private readonly \Symfony\Component\Notifier\NotifierInterface $notifier,
  ) {}

  public function myMethod(){
    $notification = (new \Symfony\Component\Notifier\Notification\Notification())
      ->subject('Test subject!')
      ->content('Test message');
    $this->notifier->send($notification, $recipient);
  }

}

Controller example ​

yaml
my_module.my_controller:
  path: '/my_controller'
  defaults:
    _controller: '\Drupal\my_module\Controller\MyController'
php
namespace Drupal\my_module\Controller;

final class MyController {

  use \Drupal\Core\DependencyInjection\AutowireTrait;

  public function __construct(
    private readonly \Symfony\Component\Notifier\NotifierInterface $notifier,
  ) {}

  public function __invoke(){

    $notification = (new \Symfony\Component\Notifier\Notification\Notification())
      ->subject('Test subject!')
      ->content('Test message');
    $this->notifier->send($notification, $recipient);
  }

}

Drupal locator ​

The \Drupal class or manually injected variant is not recommended as it may be removed as an unused public dependency from the service container. It also makes unit testing difficult.

php
namespace Drupal\my_module\Controller;

final class MyThing {

  public function myMethod(){
    $notification = (new \Symfony\Component\Notifier\Notification\Notification())
      ->subject('Test subject!')
      ->content('Test message');
      
    /** @var \Symfony\Component\Notifier\NotifierInterface $notifier */
    $notifier = \Drupal::service(\Symfony\Component\Notifier\NotifierInterface::class);
    $notifier->send($notification, $recipient);
  }

}

Sending notifications ​

To send a message to someone, you'll need a message and one or more recipient PHP objects.

Recipient object

php
final class MyRecipient implements \Symfony\Component\Notifier\Recipient\EmailRecipientInterface {
  public function __construct(
    private readonly $email,
  ) {}
  
  public function getEmail(): string {
    return $this->email;
  }
}

Sending

php
$notification = (new Notification())
  ->subject('Subject!')
  ->content('Content!');

// Sending to a recipient:
$notifier->send($notification, new MyRecipient('my-recipient@example.com'));

// `send` method accepts multiple recipients:
$notifier->send(
  $notification, 
  recipients: 
  new MyRecipient('my-recipient-1@example.com'), 
  new MyRecipient('my-recipient-2@example.com'), 
  new MyRecipient('my-recipient-3@example.com'),
);

// it also accepts zero recipients.
$notifier->send($notification);

The zero recipient option internally creates a \Symfony\Component\Notifier\Recipient\NoRecipient recipient. Not all channels support this type though. Email and SMS do not support it. It is well suited for the desktop or chat channels.

Resources ​

Further documentation for Sending can be found in the Symfony Notifier documentation