config.yml

services:
  repository:
    class: NSBundle\Repo\MyRepository
    arguments: [ @service_container ]

MyRepository.php

<?php

namespace NSBundle\Repo;

use Symfony\Component\DependencyInjection\Container;

class MyRepository
{
    public function __construct(Container $c)
    {
        $params = $c->get('request')->attributes->get('_route_params');
        $id = $params['id'];
    }
}