Error: req#logout requires a callback function

Question

can't able to find solution of this tried everything, i am just new in using passport. Error: req#logout requires a callback function i have coded this before but that time i have not received any error, but this time dont know why i am getting this, i have also read passport docs and tried every solutions

thanks in advance

<%- include('partials/header') %>

<header>
    <nav class="flex align-item-center">
        <div class="div-left">
            <img id="userimg" src="img/user.png" alt="logo">
        </div>
        <div class="div-right flex">
            <div style="font-size: 14px">
                <a href="/logout" role="button"> Logout</a>
            </div>
        </div>
    </nav>
</header>

<%- include('partials/footer') %>

---

js code

require('dotenv').config();
const express = require("express");
const bodyParser = require("body-parser");
const ejs = require("ejs");
const mongoose = require("mongoose");
const session = require('express-session');
const passport = require('passport');
const passportLocalMongoose = require('passport-local-mongoose');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const findOrCreate = require('mongoose-findorcreate');

const app = express();

app.use(express.static("public"));
app.set('view engine', 'ejs');
app.use(bodyParser.urlencoded({
    extended: true
}));

app.use(session({
    secret: process.env.SECRET,
    resave: false,
    saveUninitialized: false
}))

app.use(passport.initialize());
app.use(passport.session());

mongoose.connect("#DB")

const accountsdata = new mongoose.Schema({
    email: String,
    password: String,
    googleId: String,
    facebookId: String,
    combo: String,
    date: String,
    price: String,
    accountemail: String

});

accountsdata.plugin(passportLocalMongoose);
accountsdata.plugin(findOrCreate);

const data = new mongoose.model("amazonprime", accountsdata);

passport.use(data.createStrategy());

passport.serializeUser(function (user, cb) {
    process.nextTick(function () {
        cb(null, { id: user.id, username: user.username });
    });
});

passport.deserializeUser(function (user, cb) {
    process.nextTick(function () {
        return cb(null, user);
    });
});

passport.use(new GoogleStrategy({
    clientID: process.env.CLIENT_ID,
    clientSecret: process.env.CLIENT_SECRET,
    callbackURL: "http://localhost:3000/auth/google/home",
    userProfileURL: "https://www.googleapis.com/oauth2/v3/userinfo"
},
    function (accessToken, refreshToken, profile, cb) {
        console.log(profile)
        data.findOrCreate({ googleId: profile.id }, function (err, user) {
            return cb(err, user);
        });
    }
));

app.get("/", (req, res) => {
    res.render("login");
});

app.get('/auth/google',
    passport.authenticate("google", { scope: ["profile"] })
);

app.get("/auth/google/home",
    passport.authenticate("google", { failureRedirect: "/" }),
    function (req, res) {

        res.redirect("/home");
    });

app.get("/signup", (req, res) => {
    res.render("signup");
});

app.get("/home", function (req, res) {
    if (req.isAuthenticated()) {
        res.render("home");

    } else {
        res.redirect("/");
    }
})

app.get("/logout", (req, res) => {
    req.logout();
    res.redirect("/");
});


app.post("/signup", (req, res) => {

    data.register({ username: req.body.username }, req.body.password, function (err, user) {
        if (err) {
            console.log(err);
            res.redirect("/signup");
        } else {
            passport.authenticate("local")(req, res, function () {
                res.redirect("/home");
            })
        }
    })
})

app.post("/", function (req, res) {

    const user = new data({
        username: req.body.username,
        password: req.body.password
    })
    req.login(user, function (err) {
        if (err) {
            console.log(err);
        } else {
            passport.authenticate("local")(req, res, function () {
                res.redirect("/home")
            })
        }
    })
});

app.get("/logout", (req, res) => {
    req.logout();
    res.redirect("/");
});




app.listen(3000, function () {
    console.log("Server started on port 3000.");
});

---

error

Error: req#logout requires a callback function
    at IncomingMessage.req.logout.req.logOut (E:\Web Development\Data Handler\node_modules\passport\lib\http\request.js:65:44)
    at E:\Web Development\Data Handler\app.js:105:9
    at Layer.handle [as handle_request] (E:\Web Development\Data Handler\node_modules\express\lib\router\layer.js:95:5)
    at next (E:\Web Development\Data Handler\node_modules\express\lib\router\route.js:144:13)
    at Route.dispatch (E:\Web Development\Data Handler\node_modules\express\lib\router\route.js:114:3)
    at Layer.handle [as handle_request] (E:\Web Development\Data Handler\node_modules\express\lib\router\layer.js:95:5)
    at E:\Web Development\Data Handler\node_modules\express\lib\router\index.js:284:15
    at Function.process_params (E:\Web Development\Data Handler\node_modules\express\lib\router\index.js:346:12)
    at next (E:\Web Development\Data Handler\node_modules\express\lib\router\index.js:280:10)
    at SessionStrategy.strategy.pass (E:\Web Development\Data Handler\node_modules\passport\lib\middleware\authenticate.js:346:9)

Multi

check once i have added error stack – Multi

Answer 1

Since version 0.6.0 (which was released only a few days ago by the time of writing this), req.logout is asynchronous. This is part of a larger change that averts session fixation attacks.

See the release announcement:

The other major change is that that req.logout() is now an asynchronous function, whereas previously it was synchronous. For instance, a logout route that was previously:

app.post('/logout', function(req, res, next) {
  req.logout();
  res.redirect('/');
});

should be modified to:

app.post('/logout', function(req, res, next) {
  req.logout(function(err) {
    if (err) { return next(err); }
    res.redirect('/');
  });
});

Jared Hanson mentioned that the docs are not up to date yet:

It is necessary in order to improve the security of how sessions are managed during logout. Upgrading to 0.6.0 will require applications to pass a callback to req#logout. I'm still working on updating the docs and examples.

Keely

so express-session does not require a req.session.destroy() inside the logout logic? – Soften

Thank you for the straightforward and simple explanation. I was following Colt Steele's Web Developer Bootcamp 2023 (specifically, Section 51) on Udemy, which was created before the changes took place, so not mentioned in the video. This solution relieved a lot of stress for me. Thank you!! – Motherly

@HarshGupta: Thanks for suggesting an edit but it doesn't make sense. 1) This is a citation of the linked release notes article and it uses POST, so there it would be incorrect to write GET here. 2) It should be POST and not GET because a logout changes state, and GET is not allowed to change state, it should only read state. – Keely

Answer 2

Learner here (too?) -- I had that same problem. I was banging my head against the wall until the instructor mentioned that req.login() requires a callback function. For the callback he used an error-handling function that turned out to work well for req.logout() too.

Maybe you could try this:

app.get("/logout", (req, res) => {
  req.logout(req.user, err => {
    if(err) return next(err);
    res.redirect("/");
  });
});

Larimor

Answer 3

I encountered the same error. It would help if you used a callback function like this.

router.get("/logout", (req, res) => {
  req.logout((err) => {
    if (err) {
      return res.status(500).json({ message: "Error during logout." });
    }
    res.status(200).json({ message: "Logout successful." });
  });
});

Jasmin

Answer 4

here is my problem that is not working:

app.get("/logout", (req, res) => {
  req.logout();
  res.redirect("/");
});

The solution is:

require("dotenv").config();

const express = require("express");
const bodyParser = require("body-parser");
const ejs = require("ejs");
const mongoose = require("mongoose");
const session = require("express-session");
const passport = require("passport");
const passportLocalMongoose = require("passport-local-mongoose");

const app = express();
app.use(express.static("public"));

app.use(bodyParser.urlencoded({
  extended: true
}));

app.set("view engine", "ejs");

app.use(
  session({
    secret: "our little secret.",
    resave: false,
    saveUninitialized: false,
  })
);

app.use(passport.initialize());

app.use(passport.session());

mongoose.connect("mongodb://127.0.0.1/userDB");

const userSchema = new mongoose.Schema({
  email: String,
  password: String,
});

userSchema.plugin(passportLocalMongoose);

const User = new mongoose.model("User", userSchema);

passport.use(User.createStrategy());

passport.serializeUser(User.serializeUser());
passport.deserializeUser(User.deserializeUser());

app.get("/", (req, res) => {
  res.render("home");
});

app.get("/login", (req, res) => {
  res.render("login");
});

app.get("/register", (req, res) => {
  res.render("register");
});

app.get("/secrets", (req, res) => {
  if (req.isAuthenticated()) {
    res.render("secrets");
  } else {
    res.redirect("/login");
  }
});

app.get("/logout", function(req, res, next) {
  req.logout(function(err) {
    if (err) {
      return next(err);
    }
    res.redirect("/");
  });
});

Repro

Answer 5

<nav class="grey darken-3">
  <div class="nav-wrapper container">
    <a href="#!" class="brand-logo center">StoryBooks</a>
    <a href="#" data-target="mobile-demo" class="sidenav-trigger show-on-large"><i class="fas fa-bars"></i></a>
    <ul class="sidenav" id="mobile-demo">
      <li><a href="/stories">Public Stories</a></li>
      <li><a href="/dashboard">Dashboard</a></li>
      <li><a href="/auth/logout">Logout</a></li>
    </ul>
  </div>
</nav>

Tindal

It's important to not just post code, but to also include a description of what the code does and why you are suggesting it. This helps others understand the context and purpose of the code, and makes it more useful for others who may be reading the question or answer. – Impasto