req.session undefined in route - node.js

Question

I'm building a simple site with expressjs and passportjs and I'm running into the problem that I can't access session variables in my routes.
There are a lot of threads with this topic but the solutions don't work for me. It looks like my error is somewhere else.
My app is configured like this:
app.configure(function() {
app.set('port', process.env.PORT || 3000);
app.set('views', __dirname + '/views');
app.set('view engine', 'jade');
app.use(express.logger());
app.use(express.cookieParser());
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(express.session({
path: '/',
secret: 'very secret'
}));
app.use(passport.initialize());
app.use(passport.session());
app.use(app.router);
app.use(express.static(__dirname + '/public'));
});
Once passport verified the twitter account it's redirected to this site:
app.get('/auth/twitter/callback',
passport.authenticate('twitter', {
failureRedirect: '/login'
}),
function(req, res) {
res.redirect('/');
console.log("populate session")
populateSession(req, res);
});
This works, as I'm seeing the "populate session" output in the console if I'm logged in.
The populateSession() looks like this:
function populateSession(req, res) {
User.findOne({
twitterID: req.user.id
}, function(err, result) {
if (result) {
// Store data to session
req.session.twitterAccessToken = result.twitterAccessToken;
req.session.twitterAccessTokenSecret = result.twitterAccessTokenSecret;
req.session.lastfmAccountName = result.lastfmAccountName;
console.log("in session: " + req.session.lastfmAccountName)
}
})
}
"in session" is printed the right way. So the session itself works. Now my problem is that I want to have access to my session variables in routes because I want to pass them to my view templates like this:
app.get('/account', ensureAuthenticated, function(req, res) {
console.log(req.session)
console.log("lastfm nick " + req.session.lastfmAccountName)
res.render('account', {
user: req.user,
lastfmnick: req.session.lastfmAccountName
});
That's where I'm running into the problems. req.session contains all the twitter fields passport is populating it with but req.session.lastfmAccountName is undefined.
Any idea what's wrong there or is there a better way to pass variables to the view? I feel like it's not a good idea to have DB queries for the fields in all my routes if it could just be stored in the session.
Thanks!

Answer 1

The session will automatically be saved when the response ends, in this case by res.redirect(), which is done before the modifications are made to the session.
function(req, res) {
res.redirect('/'); // ends the response, saving the session
populateSession(req, res); // modifies the session without saving
});
Since .findOne() is asynchronous, if you revise populateSession() to take and call a callback when the find completes, you can control the order so the session is modified first:
function populateSession(req, res, next) {
User.findOne({
twitterID: req.user.id
}, function(err, result) {
if (result) {
// ...
}
if (next) next(err);
})
}
app.get('/auth/twitter/callback',
/* ... */,
function(req, res) {
populateSession(req, res, function () {
res.redirect('/');
});
});
It also allows you to use populateSession as middleware:
app.get('/auth/twitter/callback',
/* ... */,
populateSession,
function(req, res) {
res.redirect('/');
});

Answer 2

app.use(lib.express.cookieParser(lib.config.cookieSecret));
app.use(lib.express.session({
secret: 'very secret'
})
}));
This two line should be consecutive and in that order.