Symfony Ajax Controller Handler, always fires jQuery error function

I am really new with Symfony framework I am just trying to implement a simple ajax example:

Routing:

DartDartBundle_data_user:
    pattern:  /data/user
    defaults: { _controller: DartDartBundle:Data:user }
    requirements:
        _method:  POST

DataController:

namespace Dart\DartBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\JsonResponse;

class DataController extends Controller
{
    public function userAction(){      
        $content = array('success' => true, 'name' => 'luis');
        $response = new JsonResponse($content,200);
        $response->headers->set('Content-Type', 'application/json; Charset=UTF-8');
    return $response;
    }
}

And the ajax call:

$.ajax({
    type : 'GET',
    dataType: 'json',
    url : 'http://symfony.dartintelligence.com/app_dev.php/data/user',
    success : function(data){
        console.log("OK");
        console.log(data);  
    },
    error: function (xhr, ajaxOptions, thrownError){   
        console.log("SOME ERROR OCURRED");
        console.log(thrownError);
    }
});

But it always fires the error function. I don't know why. I've try without specifying jston dataType and using Response instead of JsonResponse.

I don't know whats wrong.