[FIXED] How to get the "real" IP addresses of all clients connected to websocket server

Issue

So I have a nodejs web socket server sitting behind a nginx reverse proxy. My nginx configuration looks like this:

server {
    listen 80;
    location / {
        proxy_pass ​http://localhost:9898;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header X-Forwarded-For $remote_addr;
    }
}

My web socket server application code contains logic that stores the client's IP address in a table for retrieving later. I don't have a problem retrieving the client's IP address when they connect because I can simply do something like this req.headers["x-forwarded-for"] since I have access to the req object on every new connection. My problem is retrieving that "forwarded IP address" whenever I want to send out a server broadcast only to a subset of certain clients. Because whenever I do ws._socket.remoteAddress (where ws is the web socket object), I expectantly get the IP address: 127.0.0.1.

I guess this is a question regarding the specific npm package I'm using to host a web socket server: https://www.npmjs.com/package/ws.

Solution

Your question is answered in the NPM page you linked:

When the server runs behind a proxy like NGINX, the de-facto standard is to use the X-Forwarded-For header.

wss.on('connection', function connection(ws, req) {
  const ip = req.headers['x-forwarded-for'].split(/\s*,\s*/)[0];
});

You could store that ip on the ws object (and in fact, you can maybe overwrite ws._socket.remoteAddress with that ip too) at that point.

Answered By - AKX

Answer Checked By - David Marino (PHPFixing Volunteer)