Pfthb

Node create a unique url and bind socket.io to it.

var io = require("socket.io").listen(server, path: req.originalUrl);

When a client connects also binds his socket.io-client to that url

var socket = io('192.168.1.101:3000', path: window.location.pathname);

I don't have problems and everything works great.

When a client performs a particular action, server do

socket.broadcast.emit("foo"); //I made console.log here and it prints

client-side:

socket.on("foo", () => console.log("okay"));

The problem is that client-side "foo" event is almost never fired. Sometimes it is fired but only in particular occations. For example it happened that a socket.io-client auto-reconnect to server and then the event is fired.

I don't know if the problem is related to this, because for example socket.emit works, but when another client connects I always get this
error

socket.broadcast.emit("foo");

broadcasts a message to all connected clients EXCEPT the one specified by socket. If you want to broadcast to all connected clients, then use:

io.broadcast.emit("foo");

You will also have to make sure that your clients are correctly connected and not regularly losing and re-establishing their connections (you can see if that is happening by logging the connection and disconnection events on the server). If they are losing their connections somehow and then reconnecting, then which ones would get the broadcast message would happen to depend upon which ones were not in the middle of a temporarily lost connection.