node.js – 修改代理请求的标头

isAllowed = (req,res,next) -> # Do IP check here.

base64Encode = (unencoded) -> new Buffer(unencoded or '').toString 'base64'

app.all "/demoproxy/*",isAllowed,(req,res) ->

  req.url = "/" + req.url.split("/").slice(2).join("/")

  userPass = base64Encode "#{process.env.DEMO_USERNAME}:#{process.env.DEMO_password}"

   # This doesn't work.
   # res.setHeader 'Authorization',"Basic #{userPass}"

   # This doesn't work either.
   ###res.oldWriteHead = res.writeHead

   res.writeHead = (statusCode,headers) ->

     headers = { }
     headers['Authorization'] = "Basic #{userPass}"
     res.oldWriteHead statusCode,headers###

    proxy = new httpProxy.httpProxy
      target:
        host: 'remote-api.com'
        port: 80

    proxy.proxyrequest req,res

这样做的正确方法是什么？