code: function (elm, conf) {
  
                      conf.sitekey = conf.key || config.key;
                      conf.theme = conf.theme || config.theme;
                      conf.stoken = conf.stoken || config.stoken;
                      conf.size = conf.size || config.size;
                      conf.type = conf.type || config.type;
                      conf.hl = conf.lang || config.lang;
                      conf.badge = conf.badge || config.badge;
  
                      if (!conf.sitekey) {
                          throwNoKeyException();
                      }
                      return getRecaptcha().then(function (recaptcha) {
                          var widgetId = recaptcha.render(elm, conf);
                          instances[widgetId] = elm;
                          return widgetId;
                      });
                  }
docs: Creates a new reCaptcha object
  
  @param elm  the DOM element where to put the captcha
  @param conf the captcha object configuration
  @throws NoKeyException    if no key is provided in the provider config or the directive instance (via attribute)