nginx & socket.io

client_side_script.js

var socket = io.connect('http://mydomain.com:4000');

index.html

<!-- include socket.io script, which isn't on disk, but nginx will redirect this request to node.js, and socket.io will
then serve the requested script -->

<script src="/socket.io/socket.io.js"></script>

nginx.conf

server {
	listen       80;
	server_name  mydomain.com;

	location ~ /socket.io/socket.io.js {
            proxy_pass  http://127.0.0.1:4000; # replace 4000 with the port that node.js is on
        }
}