[IBMiOSS] Node Access-Control-Allow-Origin

I'm trying to call a Node webservice from an existing app running on Apache. It's giving me problems because the app is running on a different port than Node. I did some searching, and I was able to get it to work by adding a new property to my header response:
res.writeHead(200, {
'Content-Type' : 'application/json'
, 'Access-Control-Allow-Origin' : 'http://myHostName:80' // Added this line
});

The trouble is that I have multiple production and test Apache servers, and I don't want to hardcode them all. They all have the same hostname, but I can't find a way to do a wildcard for the port#. What I got from Google, was to manually match against the calling host. If it matches, simply parrot it back for the Access-Control-Allow-Origin. The example I found returns null for me for the calling host. Here's what I found:
console.log(url.parse(req.url, true).host); //should return 'myHostName:80', but I get null



TIA