从ajaxcontroller symfony返回json

我尝试从表中查看一些行。我在Symfony中有一个AjaxController，该控制器具有以下功能：

use Symfony\Component\Serializer\Serializer;
use Symfony\Component\Serializer\Encoder\JsonEncoder;
use Symfony\Component\Serializer\Normalizer\GetSetMethodNormalizer;
use Rowoco\AllgemeinBundle\Entity\Place;
use Symfony\Component\HttpFoundation\JsonResponse;
.
.
.

public function defaultAjaxAction( $job )
{
    $user = $this->get('security.context')->getToken()->getUser();
    $userId = $user->getId();
    $result = $this->$job( $userId );

    // Initialisiert Serializer
    $encoder = [new JsonEncoder()];
    $normalizer = [new GetSetMethodNormalizer()];
    $serializer = new Serializer($normalizer, $encoder);
    $newData = $serializer->serialize($result, 'json');

    return new Response($newData);
}

public function getPlacelist( $iduser )
{
    $em = $this->getDoctrine()->getManager();
    $request = Request::createFromGlobals();

    //if i put here a return 123, then the output in the javascript-console would return 123
    $placeRepo = $em->getRepository( "RowocoAllgemeinBundle:Place" );
    $placeEntity = $placeRepo->findBy(
        array(),
        array(),
        $request->request->get( "limitCount" ),
        $request->request->get( "limitStart" )
    );
    return new JsonResponse(array('place' => $placeEntity));
}

在我的js文件中，我使用以下功能对其进行了调用：

function getPlaces()
{
    var data = {};
    data['limitCount'] = 10;
    data['limitStart'] = 0;

    var url = $( "#pageparameter" ).data( "url-getplacelist" );

    $.ajax({
            type: "POST",
            url: url,
            data: data,
            dataType: "json"
        })
        .done(function(resp){
            console.log(resp);
            $( "#viewPlaces").html(resp.place.description);
        })
        .error(function(){
            console.log("No connection");
        });

}

在表中，我有2行，并在工作台中看到它们。

我不使用存储库。我只使用symfony的基本功能。