code: @Override
      protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
          try {
              Signature signature = new Signature();
              boolean hasRights = checkSignature(signature, request);
  
              if (hasRights) {
                  log.info("signature-success:{}", signature);
                  WebUtil.outputString(response, signature.getEchostr());
              } else {
                  log.info("signature-not-match:{}", signature);
              }
          } catch (Exception e) {
              log.error("signature-error", e);
          }
      }
docs: TODO please custom it.