rest_api_common/Bundle/RestBundle/DependencyInjection/RestExtension.php

<?php

namespace PhpBenchmarksSymfony\Bundle\RestBundle\DependencyInjection;

use Symfony\Component\Config\FileLocator;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
use Symfony\Component\HttpKernel\DependencyInjection\Extension;

class RestExtension extends Extension
{
    /**
     * @param array $configs
     * @param ContainerBuilder $container
     */
    public function load(array $configs, ContainerBuilder $container)
    {
        $loader = new YamlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));
        $loader->load('services.yml');
    }
}