ContainerInterface.php

<?php

namespace Drupal\Component\DependencyInjection;

use Symfony\Component\DependencyInjection\ContainerInterface as BaseContainerInterface;

/**
 * The interface for Drupal service container classes.
 */
interface ContainerInterface extends BaseContainerInterface {
    
    /**
     * Gets all defined service IDs.
     *
     * @return array
     *   An array of all defined service IDs.
     */
    public function getServiceIds();

}