We have a requirement to generate images on the fly and cache using CDN. For this we have configured a backend service with a load balancer enabled cloud CDN. We are using Nginx proxy server. We have added headers specified in the Google cloud CDN docs, but unfortunately it is not caching.
Request:
GET /resize?size=l&url=https://example.com/image.jpeg HTTP/1.1
Host: resize.example.com
Request Headers:
Host: resize.example.com
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:70.0) Gecko/20100101 Firefox/70.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive
Upgrade-Insecure-Requests: 1
Response headers:
HTTP/1.1 200 OK
Server: nginx/1.17.2
Date: Wed, 15 Jan 2020 15:01:14 GMT
Content-Type: image/jpeg
Content-Length: 62771
cache-control: max-age=86400, public, s-maxage=86400
Via: 1.1 google