code: public static @Nullable GrailsWebRequest lookup() {
          GrailsWebRequest webRequest = null;
          RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
          if (requestAttributes instanceof GrailsWebRequest) {
              webRequest = (GrailsWebRequest) requestAttributes;
          }
          return webRequest;
      }
docs: Looks up the current Grails WebRequest instance
  @return The GrailsWebRequest instance