nodejs - efficient http proxy that directly pipes data from website to browser in under 50 lines of code

gistfile1.txt

/*jslint bitwise: true, indent: 2, nomen: true, regexp: true, stupid: true*/
(function () {
  'use strict';

  exports.requireHttp = require('http');
  exports.requireUrl = require('url');

  exports.handlerHttpProxy = function (request, response, next) {
    var kk,
      proxy = exports.requireUrl.parse(/http.*/.exec(request.url)[0]);
    //// OPTIMIZATION - disable socket pooling
    proxy.agent = false;
    proxy.headers = {};
    proxy.method = request.method;
    //// modify proxy request headers
    for (kk in request.headers) {
      if (request.headers.hasOwnProperty(kk)) {
        proxy.headers[kk] = request.headers[kk];
      }
    }
    proxy.headers.host = proxy.host;
    proxy = require(proxy.protocol.slice(0, -1)).request(proxy, function (proxyResponse) {
      response.writeHead(proxyResponse.statusCode, proxyResponse.headers);
      //// OPTIMIZATION - stream data
      proxyResponse.pipe(response);
    });
    proxy.once('error', function (err) {
      next(err);
    });
    //// OPTIMIZATION - stream data
    request.pipe(proxy);
  };

  //// test
  exports.requireHttp.createServer(function (request, response) {
    if (/^http:\/\/|^https:\/\//.test(request.url)) {
      exports.handlerHttpProxy(request, response, function (err) {
        console.error(err.stack);
        response.end(err.stack);
      });
    } else {
      response.writeHead(404);
      response.end('404 Not Found');
    }
  }).listen(8888);

  //// from command line shell, try:
  //// curl --proxy http://localhost:8888 'http://www.yahoo.com'
}());