code: @RequestMapping(method = RequestMethod.POST, value = "/registerUser")
      public ResponseEntity<String> registerUser() {
          ConfigurationHandler response =  configurationHandlerService.getConfigForRegisterUser();
  
          return new ResponseEntity<>(response.getBodyAnswer(), httpHeaders, HttpStatus.valueOf(response.getResult()));
      }
docs: Processes HTTP.POST request (URL: .../registerUser).
  @return ResponseEntity with string in JSON format with http status result (success or not) and user id.