title: Set requirements for get request parameters in symfony's controller
body: <p>I have a controller which handles a GET request. I need to set requirement parameters for GET request, e.g.: '<a href="http://localhost/site/main?id=10&amp;sort=asc" rel="nofollow">http://localhost/site/main?id=10&amp;sort=asc</a></p>
  
  <p>My controller class</p>
  
  <pre><code>class IndexController extends Controller {
  `   /**
       * @Route
       * (
       *     "/site/main", 
       *     name="main"
       * )
       *
       * @Method("GET")
       */
      public function mainAction(Request $request) 
      {
          return new Response('', 200);
      }
  }
  </code></pre>
  
  <p>How could I do that?</p>
  
  <p>UPD: I need to set requirement for URL parameters like
  id: "\d+",
  sort: "\w+"
  Etc.
  The same as symfony allows to do with POST request.</p>