Allow adding custom CAS Attributes

For those wondering how to use this feature: give your own event a priority lower than 100 (CASAttributeAlterEventSubscriber), get existing attributes ($event->getAttributes()), and then add your own before passing them to $event->setAttributes().

@FMB Would you be willing to provide a working example?

There is a request on #3311038: How to get term name instead of tid in the released attributes? →

The other possibility was https://www.drupal.org/project/cas_attributes →

@FMB Would you be willing to provide a working example?

Something like that:

namespace Drupal\mymodule\EventSubscriber;

use Drupal\cas_server\Event\CASAttributesAlterEvent;
use Drupal\Core\Database\Connection;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Pass profile UUIDs as CAS attributes.
 *
 * @see \Drupal\cas_server\EventSubscriber\CASAttributeAlterEventSubscriber
 */
class CasAttributes implements EventSubscriberInterface {

  /**
   * Connection to database.
   *
   * @var \Drupal\Core\Database\Connection
   */
  protected Connection $database;

  /**
   * Constructor.
   *
   * @param \Drupal\Core\Database\Connection $database
   *   Database connection.
   */
  public function __construct(Connection $database) {
    $this->database = $database;
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    return [
      CASAttributesAlterEvent::CAS_ATTRIBUTES_ALTER_EVENT => [
        'onCasAttributesAlter',
        // Lower than CASAttributeAlterEventSubscriber, so we can add
        // attributes.
        50,
      ],
    ];
  }

  /**
   * Actually alter CAS attributes.
   */
  public function onCasAttributesAlter(CASAttributesAlterEvent $event) {
    $attributes = $event->getAttributes();
    $bundles = ['bundle1', 'bundle2'];
    $uuids = $this->database
      ->select('profile', 'p')
      ->fields('p', ['type', 'uuid'])
      ->condition('uid', $event->getUser()->id())
      ->condition('type', $bundles, 'IN')
      ->execute()
      ->fetchAllKeyed();
    $attributes += $uuids;
    $event->setAttributes($attributes);
  }

}

The other possibility was https://www.drupal.org/project/cas_attributes →

This module is installed on the client side. My purpose here was to pass additional CAS attributes from the server to its clients.