We are using in one of our applications Cloudinary to host and resize images on the fly. We are also using Cloudflare for our CDN and DNS management.
I was given a task to setup a CNAME subdomain in CloudFlare to forward the request to Cloudinary. This way we can still have the benefit of serving static images from CDN as well as reducing the Cloudinary bandwidth usage.
My solution is to set HAProxy as a reverse proxy which responsible to fetch images from Cloudinary server. You can see the overview diagram below:
The first thing we have to do is to create an ACL in HAProxy for our cloudinary subdomain
In the configuration below, we are telling HAProxy to forward all requests from cloudinary-asset.rudylee.com to cloudinary-backend:
listen http
bind 127.0.0.1:8080
maxconn 18000
acl host_cloudinary hdr(host) -i cloudinary-asset.rudylee.com
use_backend cloudinary-backend if host_cloudinary
Next one is to create a new backend.
backend cloudinary-backend
http-request set-header Host res.cloudinary.com
server cloudinary res.cloudinary.com:80
Restart HAProxy and you should be able to use the subdomain to serve images from Cloudinary (eg: http://cloudinary-asset.rudylee.com/rudylee/image/upload/12298848/icon/12379593943923.png )
Requesting the images through SSL should work if you have SSL termination configured in your HAProxy.