public function refresh()
    {
        $url = self::classUrl() . "?id=" . $this->instanceId();
        list($resp, $usedOpts) = self::request(self::METHOD_GET, $url);
        $body = isset($resp['data'][0]) ? $resp['data'][0] : null;
        $this->install($body, $usedOpts);
        return $this;
    }