How to share sessions with Socket.IO 1.x and Express 4.x?

Question

How can I share a session with Socket.io 1.0 and Express 4.x? I use a Redis Store, but I believe it should not matter. I know I have to use a middleware to look at cookies a

Answer 1

I have kinda solved it, but it is not perfect. Does not support signed cookies etc. I used express-session 's getcookie function. The modified function is as follows:

    io.use(function(socket, next) {
        var cookie = require("cookie");
        var signature = require('cookie-signature');
        var debug = function() {};
        var deprecate = function() {};

        function getcookie(req, name, secret) {
            var header = req.headers.cookie;
            var raw;
            var val;

            // read from cookie header
            if (header) {
                var cookies = cookie.parse(header);

                raw = cookies[name];

                if (raw) {
                    if (raw.substr(0, 2) === 's:') {
                        val = signature.unsign(raw.slice(2), secret);

                        if (val === false) {
                            debug('cookie signature invalid');
                            val = undefined;
                        }
                    } else {
                        debug('cookie unsigned')
                    }
                }
            }

            // back-compat read from cookieParser() signedCookies data
            if (!val && req.signedCookies) {
                val = req.signedCookies[name];

                if (val) {
                    deprecate('cookie should be available in req.headers.cookie');
                }
            }

            // back-compat read from cookieParser() cookies data
            if (!val && req.cookies) {
                raw = req.cookies[name];

                if (raw) {
                    if (raw.substr(0, 2) === 's:') {
                        val = signature.unsign(raw.slice(2), secret);

                        if (val) {
                            deprecate('cookie should be available in req.headers.cookie');
                        }

                        if (val === false) {
                            debug('cookie signature invalid');
                            val = undefined;
                        }
                    } else {
                        debug('cookie unsigned')
                    }
                }
            }

            return val;
        }

        var handshake = socket.handshake;
        if (handshake.headers.cookie) {
            var req = {};
            req.headers = {};
            req.headers.cookie = handshake.headers.cookie;
            var sessionId = getcookie(req, "connect.sid", mysecret);
            console.log(sessionId);
            myStore.get(sessionId, function(err, sess) {
                console.log(err);
                console.log(sess);
                if (!sess) {
                    next(new Error("No session"));
                } else {
                    console.log(sess);
                    socket.session = sess;
                    next();
                }
            });
        } else {
            next(new Error("Not even a cookie found"));
        }
    });

    // Session backend config
    var RedisStore = connectRedis(expressSession);
    var myStore = new RedisStore({
        client: redisClient
    });
    var session = expressSession({
        store: myStore,
        secret: mysecret,
        saveUninitialized: true,
        resave: true
    });
    app.use(session);