同域名下，两个网站通过cookie共享登录注册功能大概思路。

// 说明：本文件代码以vue工程化项目为例，其他类型项目请自行微改!!!
// 导入js-cookie依赖
import Cookies from "js-cookie";
// 操作浏览器本地存储
const storage = window.localStorage;

// 跳转到官网登录，登录成功后会根据redirect参数，跳回之前的地址。
export function gotoLogin() {
  if (process.env.NODE_ENV === "development") {
    // 开发环境,需要在本地将官网的项目运行起来
    window.location.href =
      "http://localhost:8089/front/login/passwordlogin?redirect=" +
      window.location.href;
  } else {
    // 其他环境
    window.location.href =
      window.location.protocol +
      "//" +
      window.location.host +
      "/front/login/passwordlogin?redirect=" +
      window.location.href;
  }
}
// 跳转到官网注册，注册成功后会根据redirect参数，跳回之前的地址。
export function gotoRegister() {
  if (process.env.NODE_ENV === "development") {
    // 开发环境,需要在本地将官网的项目运行起来
    window.location.href =
      "http://localhost:8089/front/register/inputmsisdn?redirect=" +
      window.location.href;
  } else {
    // 其他环境
    window.location.href =
      window.location.protocol +
      "//" +
      window.location.host +
      "/front/register/inputmsisdn?redirect=" +
      window.location.href;
  }
}
// 在本项目中获取用户是否登录及登陆后的用户信息
/*
 * 权限相关工具函数
 */
// ！！！！！！！！！！！！！notice
export const USER_AVATAR = "ticket_avatar";
export const USER_TITLENAME = "ticket_titlename";
export const USER_AUTH = "is_auth";
export const COOKIE_AVATAR = "avatar";
export const COOKIE_NICK = "nick";
export const COOKIE_STATUS = "status";
export const COOKIE_PHONE = "phone";

// 判断用户是否登录 登录返回值为true,没登录返回值为false
export function isLogin() {
  console.log("用户状态cookie:", Cookies.get("status"));
  if (
    Cookies.get("status") &&
    Cookies.get("status") === "0" &&
    Cookies.get("is_auth")
  ) {
    return true;
  }
  return false;
}
// 获取用户信息：头像，昵称，手机号，是否实名等
export function getBasicUserInfo() {
  const u = {};
  u.avatar = Cookies.get(COOKIE_AVATAR);
  u.nick = Cookies.get(COOKIE_NICK);
  u.showPhone = Cookies.get(COOKIE_PHONE);
  u.isAuth = Cookies.get(USER_AUTH);
  return u;
}

// 退出登录,调用接口，删除cookie
export function doLogout() {
  const url =
    window.location.protocol +
    "//" +
    window.location.host +
    "/passportservice/passport/logout";
  axios
    .get(url)
    .then((res) => {
      unAuth();
      console.log("退出登录", res);
      this.$router.push({
        name: "login",
      });
    })
    .catch((response) => {
      console.log(response);
    });
}
/*
 * 退出登录，删除cookie及storage
 *
 * */
export function unAuth() {
  const opt = "";

  storage.removeItem(USER_AVATAR);
  storage.removeItem(USER_TITLENAME);
  storage.removeItem(COOKIE_PHONE);
  storage.removeItem(USER_AUTH);
  Cookies.remove(COOKIE_AVATAR, opt);
  Cookies.remove(COOKIE_NICK, opt);
  Cookies.remove(COOKIE_STATUS, opt);
  Cookies.remove(COOKIE_PHONE, opt);
  Cookies.remove(USER_AUTH, opt);
}

// 官网注册登录页面，获取url中redirect参数，并在登录/注册成功后跳转回redirect对应的url

// 1, 获取url中redirect参数的值，保存到浏览器sessionStorage中
mounted() {
  const redirectURL = this.$route.query.redirect
  if (redirectURL) {
    window.sessionStorage.setItem('redirectUrl', redirectURL)
  }
}

// 2, 登录/注册成功后，判断sessionStorage中是否有redirectUrl，存在的话跳转redirectUrl，不存在则跳转到官网首页
const redirectURL = window.sessionStorage.getItem("redirectUrl");
if (redirectURL && redirectURL.indexOf("login") === -1) {
  window.location.href = redirectURL;
  window.sessionStorage.removeItem("redirectUrl");
} else {
  return this.$router.push("/home");
}