Spring Redirect to Azure AD

StubController.java

@RestController
class StubController {

@RequestMapping("/resource/{id}")
  ModelAndView resource(ModelMap model, HttpServletRequest request, @PathVariable String id) {
      model.addAttribute("attribute", "forwardWithForwardPrefix");
      
      String client_id = "";
      int state = (int )(Math.random() * 1000000 + 1);
      String resource = "client_id_guid_of_fhir";
      String base_uri = request.getRequestURL().toString();
      base_uri = base_uri.substring(0, base_uri.length() - request.getServletPath().length());
      String redirect_uri = base_uri + "/context/authorized";

      String redirect = String.format("https://login.microsoftonline.com/common/oauth2/authorize?client_id=%s&state=%s&resource=%s&redirect_uri=%s&response_type=code&response_mode=post", client_id, state, resource, redirect_uri);
      return new ModelAndView("redirect:" + redirect, model);
  }
}