Migrating to Socket.IO 1.0

There are a few things not covered in the official guide that I had to figure out on my own. Here is an example of the changes required for a mock application using namespaces, rooms, query strings, and a reverse proxy.

Client #

var socket = io.connect('//example.com/mynamespace?mynumber=123', {
            'force new connection': true,
            'resource': 'path/to/socket.io'});
socket.on('connect_failed', function(data)
{
    console.log('connect_failed');
});
socket.on('connecting', function(data)
{
    console.log('connecting');
});
socket.on('disconnect', function(data)
{
    console.log('disconnect');
});
socket.on('error', function(reason)
{
    console.log('error');
});
socket.on('reconnect_failed', function(data)
{
    console.log('reconnect_failed');
});
socket.on('reconnect', function(data)
{
    console.log('reconnect');
});
socket.on('reconnecting', function(data)
{
    console.log('reconnecting');
});
socket.socket.disconnect();

Becomes

var socket = io(window.location.protocol + '//example.com/mynamespace?mynumber=123', {
            'multiplex': false,
            'path': '/path/to/socket.io'});
socket.on('disconnect', function(data)
{
    console.log('disconnect');
});
socket.disconnect();

Things to note:

• You can no longer use a protocol relative url for connection.
• There’s an extra / in the path.
• You no longer get detailed reconnection events. Instead, you just assume that it’s attempting to reconnect when you get a disconnect event.

Server #

var io = socketio.listen(server);

io.configure('development', function()
{
    io.set('browser client', false);
    io.set('log level', 3);
});

io.set('authorization', function(data, accept)
{
    var query = data.query;
    data.myNumber = query.mynumber;
    accept(null, true);
});

io.of('mynamespace').addListener('connection', function(socket)
{
    var myNumber = socket.handshake.myNumber;
    console.log(myNumber, 'connected');
    socket.join('myroom');
    var roomClients = io.of('mynamespace').clients('myroom');
    for(var i = 0; i < roomClients.length; i++)
    {
        console.log(roomClients[i].handshake.myNumber, 'is in myroom');
    }
}

Becomes

var io = socketio.listen(server);
var socketData = {};

if(!process.env.NODE_ENV)
{
    io.attach(server, {
        'serveClient': false
    });
});

io.use(function(socket, next)
{
    var query = socket.request._query;
    socketData[socket.id] = {
        myNumber: query.mynumber
    };
    next();
});

io.of('mynamespace').addListener('connection', function(socket)
{
    var myNumber = socketData[socket.id].myNumber;
    console.log(myNumber, 'connected');
    var roomClients = io.of('mynamespace').adapter.rooms['myroom'];
    for(var socketId in roomClients)
    {
        if(roomClients.hasOwnProperty(socketId))
        {
            console.log(io.of('mynamespace').connected[socketId], 'is in myroom');
        }
    }
}

Things to note:

• The io.configure method is gone.
• Socket.IO 1.0 uses the debug module, so you set the log level when calling Node.js.
• There are methods on the server object for each configuration option, but I found that they didn’t work, so I had to pass all the options into the attach call.
• You can no longer store data on the handshake object.
• For no apparent reason, you have to access the query parameters through the socket.request._query property.
• Also for no apparent reason, you can’t get a list of the sockets connected to a room. You have to get socket ids from namespace.adapter.rooms property, then look up the actual socket in the namespace.connected property.

nginx #

The last thing I had to do was reconfigure my reverse proxy, which happens to be nginx. Because Socket.IO 1.0 uses a different handshake that requires more requests to be sent, I had to increase the allowed request rate for the connection to be established in a reasonable amount of time.

limit_req_zone  $binary_remote_addr  zone=nodejs:10m  rate=1r/s;

Becomes

limit_req_zone  $binary_remote_addr  zone=nodejs:10m  rate=8r/s;