app.js

'use strict';

var http = require('http');

var app = http.createServer(function (req, res) {
  if ('/foo' === req.url) {
    setTimeout(function() {
      res.writeHead(200);
      res.write('foo');
      res.end();
    }, 500);
  }
  if ('/bar' === req.url) {
    var options = {
      host: '127.0.0.1',
      port: 3000,
      path: '/foo',
      method: 'GET'
    };
    var request = http.request(options, function(result) {
      (result).pipe(res);
    });
    request.end();
  }
});

app.listen(3000);