Using ngrok to expose any local server to the Internet

Ngrok is here for some time and it's a great tool that makes it possible to expose a website from local machine to the Internet by creating a tunnel from ngrok's infrastructure to your machine. This post adds 2 cents to this story. The story begins when you have a web app but not necessarily on your local machine but somewhere nearby at your local network. Sure, you can log into the local server and run ngrok there. But another approach is to have a HTTP proxy, from your machine to the local server. One of simplest and cleanest proxies that do the job would be this tiny node.js snippet

var httpProxy = require('http-proxy');

httpProxy.createProxyServer({
    target       : 'http://a.server.in.your.local.network:80', 
    changeOrigin : true, 
    autoRewrite  : true 
})
.listen(3000);

The two options make sure that both host and location headers are correctly rewritten. Please consult the list of other available options of the http-proxy module if you need more specific behavior. Then just invoke the ngrok as usual

ngrok http 3000

navigate to the address returned by ngrok and you will get the response from the server behind the proxy.