Get Cloudflare's HTTP_CF_IPCOUNTRY header with javascript?

Question

There are many SO questions how to get http headers with javascript, but for some reason they don\'t show up HTTP_CF_IPCOUNTRY header.

If I try to do with php echo

Answer 1

Yes you have to hit the server - but it doesn't have to be YOUR server.

I have a shopping cart where pretty much everything is cached by Cloudflare - so I felt it would be stupid to go to MY server to get just the countrycode.

Instead I am using a webworker on Cloudflare (additional charges):

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {

  var countryCode = request.headers.get('CF-IPCountry');

  return new Response(

    JSON.stringify({ countryCode }),

    { headers: {
      "Content-Type": "application/json"
    }});
}

You can map this script to a route such as /api/countrycode and then when your client makes an HTTP request it will return essentially instantly (for me it's about 10ms).

 /api/countrycode
 {
    "countryCode": "US"
 }

Couple additional things:

• You can't use webworkers on all service levels
• It would be best to deploy an actual webservice on the same URL as a backup (if webworkers aren't enabled or supported or for during development)
• There are charges but they should be neglibible
• It seems like there's a new feature where you can map a single path to a single script. That's what I am doing here. I think this used to be an enterprise only feature but it's now available to me so that's great.
• Don't forget that it may be T1 for TOR network