a simple reverse proxy server with http proxy

reverse_proxy_with_proxy.js

const http = require('http');

const PROXY_PASS = 'http://www.google.com';
const HTTP_PROXY_PORT = 8888;
const HTTP_PROXY_HOST = '127.0.0.1';

const getOptions = (request) => ({
  hostname: HTTP_PROXY_HOST,
  port: HTTP_PROXY_PORT,
  path: PROXY_PASS + request.url,
  headers: request.headers,
  method: request.method,
});

http.createServer().on('request', (request, response) => {
  request.pipe(http.request(getOptions(request), (res) => {
    response.writeHead(res.statusCode, res.headers);
    res.pipe(response);
  }));
}).on('upgrade', (request, socket) => {
  http.request(getOptions(request)).on('upgrade', (res, sock) => {
    const CRLF = '\r\n'
    const headers = res.rawHeaders.map((header, i) => header + (i & 1 ? CRLF : ': ')).join('');
    const head = `HTTP/${res.httpVersion} ${res.statusCode} ${res.statusMessage}${CRLF}${headers}${CRLF}`;
    socket.write(head);
    socket.pipe(sock).pipe(socket);
  }).end();
}).listen(80, '0.0.0.0');