Can't set headers after they are sent. Express JS

Question

Help me :(, i cannot find solution for my error, i try using return before my response it dosen't work

function isAuthenticated(req, res, next) {
var getToken = req.cookies.token;
var getUrl = req.originalUrl;
console.log(getToken)    
if(getToken == undefined) {
    res.redirect('/login')
    next()
} else {
    console.log('success')
    next()
}
next() }

router.get('/login', isAuthenticated, auth.login);
router.get('/logout', isAuthenticated, auth.logout);
router.post('/logging', auth.prosesLogin);

Possible duplicate of [Error: Can't set headers after they are sent to the client](https://stackoverflow.com/questions/7042340/error-cant-set-headers-after-they-are-sent-to-the-client) — ponury-kostek, Jul 09 '17 at 11:23
Remove `next()` after `else { }` and in the `if` condition. You must redirect to the endpoint only if authentication has been successful (i.e. calling `next()`). Otherwise, you must redirect to `/login`. (here is fiddle: https://jsfiddle.net/h0e2hsau/1/ ) — oneturkmen, Jul 09 '17 at 11:48
but wait it's still loop,. GET /auth/logout and, my error it's not show up anymore, but still not redirect to /auth/login url :( — Subiyantoro, Jul 09 '17 at 12:02
@Subiyantoro remove `isAuthenticated` from `GET @ /login` endpoint. No point to validate if person is not logged in yet, right? — oneturkmen, Jul 09 '17 at 12:03
@alwaysone yes that's right, but later i want GET @ /login using isAuthenticated middleware to for checking if user request to url @ /login and authenticated it will be redirect to another page. that's code for example i testing my middleware for redirecting page but still error :( — Subiyantoro, Jul 09 '17 at 12:11
Let's move to the chat [here](http://www.e-chat.co/room/220911) — oneturkmen, Jul 09 '17 at 12:16

score 4 · Accepted Answer · answered Jul 09 '17 at 13:16

4

It seems that in your functions, the order of function arguments is wrong.

Instead of (err, res) make (req, res) or (err, req, res, next). Hope this helps.

answered Jul 09 '17 at 13:16

oneturkmen

1,288
1
11
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score 3 · Answer 2 · answered Feb 03 '18 at 06:07

3

Replace next() with return false.

answered Feb 03 '18 at 06:07

Dan King

564
10
18

Can't set headers after they are sent. Express JS

2 Answers2