Reverse Proxy Server

index.js

const url = require('url')
const net = require('net')
const http = require('http')
const https = require('https')

const [HOST, PORT = 8000] = process.argv.slice(2)
const target = url.parse(HOST.startsWith('http') ? HOST : `http://${HOST}`)
console.log('Reverse proxy', target.href, '@', PORT)

const server = http.createServer().listen(parseInt(PORT))

server.on('request', (req, res) => {
	req.pipe(
		(target.protocol === 'http:' ? http : https)
		.request({
			...url.parse(target.resolve(req.url)),
			host: target.hostname,
			method: req.method,
			headers: {
				...req.headers,
				host: target.hostname
			}
		})
		.on('response', proxyRes => {
			console.log(req.method, req.url, proxyRes.statusCode)
			res.writeHead(proxyRes.statusCode, proxyRes.headers)
			proxyRes.pipe(res)
		})
		.on('error', () => res.end())
	)
})