如果用户在 express js 中尝试访问登录路由时已经登录，我想重定向到仪表板

Question

中间件

const isAuthenticate = async (req, res, next) => {
  const token = req.cookies.jwt;
if (token) {
    jwt.verify(token, "thisisjwtsecret", async (err, token_decode) => {
      if (!err) {
        const u_id = token_decode._id;
        const userData = await User.findOne({ _id: u_id });
        req.user = userData;
        req.isAuth = true;
        next();
      } else {
        res.redirect("/user/login");
      }
    });
  } else {
    res.redirect("/user/login");
    }
};

Route.js

// Auth Controller
const AuthController = require("../../controllers/auth/AuthController");
const { isAuthenticate } = require("../../middlewares/isAutheticated");

router.get("/user/login", isAuthenticate, AuthController.login);
router.post("/user/login", AuthController.checkLogin);
router.get("/user/register", isAuthenticate, AuthController.createUser);
router.post("/user/register", isAuthenticate, AuthController.storeUser);
module.exports = router;

登录函数

// Showing Login Page to User
const login = (req, res) => {
  return res.render("auth/login");
};

Answer 1

您可以从现有的 isAuthenticate() 函数中分离出功能，因此它只是 returns 一个结果，然后使用它来执行如下操作：

const { promisify } = require('util');
const verify = promisify(jwt.verify);

// resolves if jwt cookie verifies and user found
// rejects if jwt cookie is missing or doesn't verify or user not found
async function isLoggedIn(req) {
    const token = req.cookies.jwt;
    if (!token) throw new Error("no jwt cookie");
    const token_decode = await verify(token, "thisisjwtsecret");
    let user = await User.findOne({ _id: token_decode._id });
    if (!user) throw new Error("user not found");
    return;
}

// Showing Login Page to User
// Or redirect to /dashboard if already logged in
const login = async (req, res) => {
    try {
        await isLoggedIn(req);
        // already logged in, redirect to dashboard
        // you MUST make sure that /dashboard does not redirect to /user/login itself
        // when isLoggedIn resolves to avoid circular redirects
        res.redirect("/dashboard");
    } catch (e) {
        // not logged in, render the login page
        res.render("auth/login");
    }
};

isLoggedIn(req) 函数解析令牌是否有效并且在数据库中找到了用户。否则，它拒绝。然后您可以在其他路由中使用它来决定是否要重定向。

如果用户在 express js 中尝试访问登录路由时已经登录，我想重定向到仪表板

I want to redirect to dashboard if user is already logged in when he try to access login route in express js

javascript

node.js

express

authentication

middleware