// Return a JsonModel from the controller action
// To send JSON to the client when the Accept header isn’t application/json,
// we use a JsonModel in a controller action like this:

namespace Application\Controller;

use Zend\Mvc\Controller\ActionController;
use Zend\View\Model\ViewModel;
use Zend\View\Model\JsonModel;

class IndexController extends ActionController
{

  public function indexAction()
  {

    $result = new JsonModel(array(
      'some_parameter' => 'some value',
      'success'=>true,
    ));

    return $result;

  }

}