Check scope on apigility authenticated resource

UsuarioResource.php

<?php

namespace API\V1\Rest\Usuario;

use ZF\Apigility\Doctrine\Server\Resource\DoctrineResource;
use Oauth2;
use ZF\ApiProblem\ApiProblem;
use ZF\Rest\ResourceEvent;

class UsuarioResource extends DoctrineResource
{
    /**
     *
     * @var Oauth2\Server
     */
    private $oauthServer;


    /**
     * Validar todas ações da API de acordo com o scope padrão cadastro:usuario
     * @param  ResourceEvent
     * @return mixed
     */
    public function dispatch(ResourceEvent $event)
    {
        if (!$this->checkScope('cadastro:usuario')) {
            return new ApiProblem(401, 'Scope não autorizado');
        }
        return parent::dispatch($event);
    }

    /**
     * Verificar o scope
     * @param  string nome dos scopes
     * @return boolean
     */
    private function checkScope($scopeRequired)
    {
        $request = OAuth2\Request::createFromGlobals();
        $response = new OAuth2\Response();
        if ($this->getOauthServer()->verifyResourceRequest($request, $response, $scopeRequired)) {
            return true;
        }
        return false;
    }

    private function getOauthServer()
    {
        if ($this->oauthServer == null) {
            $serverInstance = $this->getServiceManager()->get('ZF\OAuth2\Service\OAuth2Server');
            $this->oauthServer = $serverInstance();
        }
        return $this->oauthServer;
    }
}