docs: public boolean preHandle(HttpServletRequest request,
                               HttpServletResponse response, Object handler) throws Exception {
  
          String queryString = request.getQueryString() == null ? "" : request.getQueryString();
  
          if (ConfigurationService.getInstance().isValid()
                  || request.getServletPath().startsWith("/configuration")
                  || request.getServletPath().startsWith("/resources")
                  || queryString.contains("requestFromConfiguration=true")) {
              return true;
          } else {
              response.sendRedirect("configuration");
              return false;
          }
      }