CORS NodeJS Middleware

cors.coffee

exports.cors = (req, res)->
  origin = (req.headers.origin || "*")
  if req.method.toUpperCase() == 'OPTIONS'
    res.writeHead 200,
      'Access-Control-Allow-Origin': origin
      'Access-Control-Allow-Credentials': true
      'Access-Control-Allow-Methods': '*'
      'Access-Control-Allow-Headers': 'Accept, Authorization, Cache-Control, Content-Type, Origin, Referer, User-Agent, X-CSRF-Token'
      'Content-Type': 'text/plain'
      'Server': 'jsonapi'
      'Content-Length': 2

    res.end('ok')
    true
  else
    res.setHeader 'Access-Control-Allow-Origin', origin
    res.setHeader 'Access-Control-Allow-Methods', '*'
    res.setHeader 'Access-Control-Allow-Headers', 'Content-Type'
    false

server.coffee

http = require('http')
cors = require('./cors')

server = http.createServer()
server.on 'request', (req, res)->
  return if cors.cors(req, res)
  
  res.end("Hello Werld")

server.listen(3000)