postoffice-1.0.x-dev/src/EventSubscriber/DefaultAddressSubscriber.php

<?php

namespace Drupal\postoffice\EventSubscriber;

use Drupal\Core\Config\ConfigFactoryInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Mailer\Event\MessageEvent;
use Symfony\Component\Mime\Address;
use Symfony\Component\Mime\Email;

/**
 * Message subscriber which sets the site email as the default address.
 *
 * Runs with priority -200 (after Symfony MessageListener which is
 * responsible for body rendering).
 */
class DefaultAddressSubscriber implements EventSubscriberInterface {

  /**
   * The config factory.
   */
  protected ConfigFactoryInterface $configFactory;

  /**
   * Constructs a new default address subscriber.
   */
  public function __construct(ConfigFactoryInterface $configFactory) {
    $this->configFactory = $configFactory;
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents(): array {
    $events = [];
    $events[MessageEvent::class] = ['onMessage', -200];
    return $events;
  }

  /**
   * Generate a text fallback if possible.
   */
  public function onMessage(MessageEvent $event): void {
    $message = $event->getMessage();
    $envelope = $event->getEnvelope();
    if ($message instanceof Email) {
      if (empty($message->getSender())) {
        $message->sender($this->getDefaultSender());
      }
      if (empty($envelope->getSender())) {
        $envelope->setSender($message->getSender());
      }
      if (empty($message->getFrom())) {
        $message->from($this->getDefaultFrom());
      }
      if (empty($message->getTo())) {
        $message->to($this->getDefaultTo());
      }
    }
  }

  /**
   * Get default sender address.
   */
  protected function getDefaultSender(): Address {
    return $this->getSiteAddress();
  }

  /**
   * Get default from address.
   */
  protected function getDefaultFrom(): Address {
    return $this->getSiteAddress();
  }

  /**
   * Get default to address.
   */
  protected function getDefaultTo(): Address {
    return $this->getSiteAddress();
  }

  /**
   * Determine site email.
   */
  protected function getSiteAddress(): Address {
    $config = $this->configFactory->get('system.site');
    // Get the custom site notification email to use as the from email address
    // if it has been set.
    $siteMail = $config->get('mail_notification');
    // If the custom site notification email has not been set, we use the site
    // default for this.
    if (empty($siteMail)) {
      $siteMail = $config->get('mail');
    }
    if (empty($siteMail)) {
      $siteMail = ini_get('sendmail_from');
    }

    return new Address($siteMail, $config->get('name'));
  }

}