Socket.io Express 3.0 session retrieval function

session.js

io.set('authorization', function(handshake, callback) { 
  if (handshake && handshake.headers && handshake.headers.cookie) {
		cookieParser(handshake, {}, function(err) {
			if(err) {
					return callback('COOKIE_PARSE_ERROR', false);
			}
			var sessionId = handshake.signedCookies[config.cookie];
			sessionStore.load(sessionId, function(err, session) {
				if(err || !session) {//|| !session.auth || !session.auth.loggedIn) {
					callback('NOT_LOGGED_IN', false);
				}
				else{
					// console.log(Object.keys(session));
					handshake.session = session;
					callback(null, true);
				}
			});
		});
	} else {
			return callback('MISSING_COOKIE', false);
	}
});