Q:

Render controller in TWIG and show form errors

I have indexAction and contactAction
contactAction is a simple form with no mapped fields (FormType) like below:
/**
 * @Route("/contact", name="contact")
 * @Template()
 * @param Request $request
 * @return array
 */
public function contactAction(Request $request)
{
    $form = $this->createForm(new ContactType());

    $form->handleRequest($request);

    if ($form->isValid()) {
        $firstName = $form->get('first_name')->getData();
        $lastName = $form->get('last_name')->getData();
        $email = $form->get('email')->getData();
        $message = $form->get('message')->getData();
    }
    return array(
        'form' => $form->createView()
    );
}

and i render this form in my indexAction with this TWIG command:
{{ render(controller('RusselBundle:Default:contact')) }}

Everything is okey, if page is not reloaded, HTML5 validators works fine, but if form have some errors like: firstName length, error's not show at all, how can i do, so that errors showed up in the form indexAction?  Any help would be appreciated. I'm just curious it's possible, and if - how ? Sorry for my english.... 

A:

Rather than using the request passed into the action you should get the master request from the request stack. As @DebreczeniAndrás says, when you use the render(controller()) you are using a newly created sub-request rather than the request that was actually passed to the page on load (the master request).
public function contactAction(Request $request)
{
    $request = $this->get('request_stack')->getMasterRequest();

    $form = $this->createForm(new ContactType());

    //...
}

