后端生成session，并且将session保存在request里面

       //登录成功生成session
                    request.getSession().setAttribute("user",user);
                    String sessionId = request.getRequestedSessionId();
                    return R.ok().data("JSESSIONID",sessionId).data("USER",user);

    /**
     * 从session中获取用户信息
     * @return
     */
    public static User getRequestUser(){
   
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        User user=(User)request.getSession().getAttribute("user");
        return user;
    }