Why is PassportJS in Node not removing session on logout
I am having trouble getting my system to log out with PassportJS. It seems the logout route is being called, but its not removing the session. I want it to return 401, if the user is not logged in in specific route. I call authenticateUser to check if user is logged in.
Thanks a lot!
/******* This in index.js *********/
// setup passport for username & passport authentication
adminToolsSetup.setup(passport);
// admin tool login/logout logic
app.post("/adminTool/login",
passport.authenticate('local', {
successRedirect: '/adminTool/index.html',
failureRedirect: '/',
failureFlash: false })
);
app.get('/adminTool/logout', adminToolsSetup.authenticateUser, function(req, res){
console.log("logging out");
console.log(res.user);
req.logout();
res.redirect('/');
});
// ******* This is in adminToolSetup ********
// Setting up user authentication to be using user name and passport as authentication method,
// this function will fetch the user information from the user name, and compare the password for authentication
exports.setup = function(passport) {
setupLocalStrategy(passport);
setupSerialization(passport);
}
function setupLocalStrategy(passport) {
passport.use(new LocalStrategy(
function(username, password, done) {
console.log('validating user login');
dao.retrieveAdminbyName(username, function(err, user) {
if (err) { return done(err); }
if (!user) {
return done(null, false, { message: 'Incorrect username.' });
}
// has password then compare password
var hashedPassword = crypto.createHash('md5').update(password).digest("hex");
if (user.adminPassword != hashedPassword) {
console.log('incorrect password');
return done(null, false, { message: 'Incorrect password.' });
}
console.log('user validated');
return done(null, user);
});
}
));
}
function setupSerialization(passport) {
// serialization
passport.serializeUser(function(user, done) {
console.log("serialize user");
done(null, user.adminId);
});
// de-serialization
passport.deserializeUser(function(id, done) {
dao.retrieveUserById(id, function(err, user) {
console.log("de-serialize user");
done(err, user);
});
});
}
// authenticating the user as needed
exports.authenticateUser = function(req, res, next) {
console.log(req.user);
if (!req.user) {
return res.send("401 unauthorized", 401);
}
next();
}
Brice’s answer is great, but I still noticed an important distinction to make; the Passport guide suggests using .logout()
(also aliased as .logOut()
) as such:
app.get('/logout', function(req, res){
req.logout();
res.redirect('/'); //Can fire before session is destroyed?
});
But as mentioned above, this is unreliable. I found it behaved as expected when implementing Brice’s suggestion like this:
app.get('/logout', function (req, res){
req.session.destroy(function (err) {
res.redirect('/'); //Inside a callback… bulletproof!
});
});
Hope this helps!
Ran into the same issue. Using req.session.destroy();
instead of req.logout();
works, but I don't know if this is the best practice.
session.destroy
may be insufficient, to make sure the user is fully logged out you have to clear session cookie as well.
The issue here is that if your application is also used as an API for a single page app (not recommended but quite common) then there can be some request(s) being processed by express that started before logout and end after logout. If this were the case then this longer running request will restore the session in redis after it was deleted. And because the browser still has the same cookie the next time you open the page you will be successfully logged in.
req.session.destroy(function() {
res.clearCookie('connect.sid');
res.redirect('/');
});
That's the what maybe happening otherwise:
- Req 1 (any request) is received
- Req 1 loads session from redis to memory
- Logout req received
- Logout req loads session
- Logout req destroys session
- Logout req sends redirect to the browser (cookie is not removed)
- Req 1 completes processing
- Req 1 saves the session from memory to redis
- User opens the page without login dialog because both the cookie and the session are in place
Ideally you need to use token authentication for api calls and only use sessions in web app that only loads pages, but even if your web app is only used to obtain api tokens this race condition is still possible.
I was having the same issue, and it turned out to not be a problem with Passport functions at all, but rather in the way I was calling my /logout
route. I used fetch to call the route:
(Bad)
fetch('/auth/logout')
.then([other stuff]);
Turns out doing that doesn't send cookies so the session isn't continued and I guess the res.logout()
gets applied to a different session? At any rate, doing the following fixes it right up:
(Good)
fetch('/auth/logout', { credentials: 'same-origin' })
.then([other stuff]);
I was having the same issues, capital O fixed it;
app.get('/logout', function (req, res){
req.logOut() // <-- not req.logout();
res.redirect('/')
});
Edit: this is no longer an issue.