public function render(Request $request, Response $response) {
        $key = $response->getResults('captcha');

        $content = $response->getContent();
        $content .= '<script src="https://www.google.com/recaptcha/api.js"></script>';
        $content .= '<div class="form-group"><div class="g-recaptcha" '
                    . 'data-sitekey="'.$key.'"></div></div>';
        $response->setContent($content);

        return $this;
    }