Express Node JS, how do we get the requesting user's IP ?

The request-ip package seems to be very effective in this regard
npm install request-ip --save

Below is the usage for this

const requestIp = require('request-ip');
app.use(requestIp.mw())

app.use(function(req, res) {
    const ip = req.clientIp;
    res.end(ip);
});

It looks for specific headers in the request and falls back to some defaults if they do not exist.

The user ip is determined by the following order:

    X-Client-IP
    X-Forwarded-For (Header may return multiple IP addresses in the format: "client IP, proxy 1 IP, proxy 2 IP", so we take the the first one.)
    CF-Connecting-IP (Cloudflare)
    Fastly-Client-Ip (Fastly CDN and Firebase hosting header when forwarded to a cloud function)
    True-Client-Ip (Akamai and Cloudflare)
    X-Real-IP (Nginx proxy/FastCGI)
    X-Cluster-Client-IP (Rackspace LB, Riverbed Stingray)
    X-Forwarded, Forwarded-For and Forwarded (Variations of #2)
    req.connection.remoteAddress
    req.socket.remoteAddress
    req.connection.socket.remoteAddress
    req.info.remoteAddress

If an IP address cannot be found, it will return null.

References:
https://www.npmjs.com/package/request-ip


Express, node JS. How to get the local IP where the app runs

Below are the properties from the Connection where we get the IP address and the port info.

req.connection.localAddress
req.connection.localPort

However this was not giving the public


References:
https://stackoverflow.com/questions/38423930/how-to-retrieve-client-and-server-ip-address-and-port-number-in-node-js