http forker

httpforker.coffee

# fork http traffic
# e.g. proxy is your production system
# and proxy2 your testing setup

http = require "http"

PRODUCTION_HOST = "localhost"
PRODUCTION_PORT = 8081
TESTING_HOST = "localhost"
TESTING_PORT = 8082

SERVER_HOST = "localhost"
SERVER_PORT = 8080

http.globalAgent.maxSockets = 500

server = http.createServer (req, res) ->

  # stolen from node-http-proxy source
  if req.headers["x-forwarded-for"]
    req.headers["x-forwarded-for"] += "," + req.connection.remoteAddress || req.socket.remoteAddress
  else
    req.headers["x-forwarded-for"] = req.connection.remoteAddress || req.socket.remoteAddress

  if req.headers["x-forwarded-port"]
    req.headers["x-forwarded-port"] += "," + req.connection.remotePort || req.socket.remoteAddress
  else
    req.headers["x-forwarded-port"] = req.connection.remotePort || req.socket.remoteAddress

  options =
    host: PRODUCTION_HOST
    port: PRODUCTION_PORT
    path: req.url
    method: req.method
    headers: req.headers

  proxyRequest = http.request options, (response) ->
    response.on "data", (data) -> res.write data #, "binary"
    response.once "end", -> res.end()
    response.headers.connection = "close" #TODO ???
    res.writeHead response.statusCode, response.headers

  options.port = TESTING_PORT
  options.host = TESTING_HOST
  proxyRequest2 = http.request options

  proxyRequest.once "error", (error) -> console.log error
  proxyRequest2.once "error", (error) -> console.log error

  # handle data from client to proxy
  # forward data to upstream servers
  req.on "data", (data) ->
    try
      proxyRequest.write data #, "binary"
    catch e
      console.log e
    try
      proxyRequest2.write data
    catch e
      console.log e

  # handle end event from client
  # end request of upstream servers
  req.once "end", ->
    try
      proxyRequest.end()
    catch e
      console.log e
    try
      proxyRequest2.end()
    catch e
      console.log e

server.listen SERVER_PORT, SERVER_HOST

(http.createServer (req, res) ->
  #console.log "Request on production system #{req.method} #{req.url}"
  #console.log ("#{key}: #{value}" for key, value of req.headers).join "\n"
  res.writeHead 200
  res.end()
).listen PRODUCTION_PORT, PRODUCTION_HOST

(http.createServer (req, res) ->
  #console.log "Request on testing system #{req.method} #{req.url}"
  #console.log ("#{key}: #{value}" for key, value of req.headers).join "\n"
  res.writeHead 200
  res.end()
).listen TESTING_PORT, TESTING_HOST