node duplicating proxy

.gitignore

node_modules

package.json

{
  "name": "urban-proxy",
  "version": "0.0.1",
  "dependencies": {
    "http-proxy": "0.7.6"
  }
}

Procfile

web: node web.js

web.js

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

var heroku = {host: 'proxy.heroku.com', port: 80};
var noResponse = {writeHead: function() {}, end: function() {}};
var percentage = parseInt(process.env.PERCENTAGE || 0);

httpProxy.createServer(function(req, res, proxy) {
  req.headers.host = "urban-production-192.heroku.com";
  delete req.headers['accept-encoding'];
  proxy.proxyRequest(req, res, heroku);

  if (percentage > Math.random() * 100) {
    req.headers.host = "urban-postgres.heroku.com";
    proxy.proxyRequest(req, noResponse, heroku);
  }
}).listen(process.env.PORT || 80);

SO URBAN