a simple reverse proxy using Node

server.js

var http = require("http"),
    util = require("util")

http.createServer(function(req, rsp){
  var regex = /^\/(v1|v2)/g
 
  var matches = req.url.match(regex)

  if((matches && matches[0] === "/v1") || (req.headers["x-api-version"] === "v1"))
    var port = 8001
  
  if((matches && matches[0] === "/v2") || (req.headers["x-api-version"] === "v2"))
    var port = 8002

  var url = req.url.replace(regex, "")

  if(port){
    var options = {
      host: 'localhost',
      port: port,
      path: url,
      method: req.method,
      headers: req.headers
    }
    
    proxy = http.request(options, function(response){

      rsp.writeHead(response.statusCode, response.headers)

      response.on("data",function(chunk){
        rsp.write(chunk)
      })

      response.on("end", function(){
        rsp.end()
      })

    })
    
    proxy.once("error", function(){ })
    
    util.pump(req, proxy)

    req.on('end', function () {
      proxy.end()
    })
  }else{
    var body = "Please specify a version.\n"
    
    rsp.writeHead(303,{ 
      "Content-Length": body.length,
      "Location": "/v1" + req.url
    })

    rsp.end(body)
  }

}).listen(8000)