How to prevent Node.js sending success header to ajax post request - ajax

Question

I am trying to send a success status to the ajax request using res.end('{"success" : "Updated Successfully", "status" : 200}'); but run into this error: Error: Can't set headers after they are sent. Basically when the user data is saved on the server I want ajax to refresh the page, although, I think somewhere in this in the app.post a success message is being sent before I try to manually do it. How can I prevent any success message being sent to the ajax post request so I can do it manually.
app.post('/signup', function (req, res) {
var userDetails = User({
username: req.body.username,
email: req.body.email,
password: bcrypt.hashSync(req.body.password1, bcrypt.genSaltSync(10))
});
User.findOne({
$or: [{
'username': req.body.username
}, {
'email': req.body.email
}]
}, function (err, user) {
if (user) {
if (allClients.indexOf(req.body.socket)) {
if (user.username === req.body.username) {
io.to(req.body.socket).emit('userInfo', 'That username is already in use.');
} else {
}
if (user.email === req.body.email) {
io.to(req.body.socket).emit('userInfo', 'That email is already in use.');
} else {
}
} else {
console.log('timeout error 822')
}
} else {
req.login(userDetails, function (err) {
if (!err) {
userDetails.save(function (err) {
if (err) throw err;
res.end('{"success" : "Updated Successfully", "status" : 200}');
res.redirect('/');
});
} else {
console.log(err)
}
})
}
if (err) {
return done(err);
}
});
});
This is my ajax request
$("#form1").submit(function(e) {
e.preventDefault();
$.ajax({
datatype: "json",
type: "POST",
url: '/signup',
data: $(this).serialize(),
success: function(result)
{
console.log(result);
if(result.status == 200){
window.location.reload(true);
}
}
});
});

Answer 1

I think the problem is in the code:
res.end('{"success" : "Updated Successfully", "status" : 200}');
res.redirect('/');
Replace the above with only
res.status(200).send({"success" : "Updated Successfully", "status" : 200})
res.redirect is to take the user to another page(it calls a get route). The error you are getting is because node is confused between sending the response back to ajax or to redirect.