How to determine the HTTP Headers sent by a CDN

I wanted to detect if a request sent to the origin was sent via a CDN or not. With Akamai at least we can add a setting to the akamai property to add a HTTP header to the request sent to the origin to determine if it's sent via the CDN or is a legitmate request.

It's possible to do this when using nginx. To log the HTTP request headers we enable debugging on in the nginx logs

/var/nginx/nginx.conf

To turn on debugging make the following change:

error_log /var/log/nginx/error.log debug;

Then restart the server:

sudo service nginx restart

Once this done, make a request which will invoke the CDN from the logs:

2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Accept: image/png;q=1.0,image/jpeg;q=0.6,image/gif;q=0.4,image/*;q=0.2,*/*;q=0.1"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "X-Image-Server-TTL: 3"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "X-Aka-Imaging-Request: 1"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US) AkamaiImageServer VelocitudeMP/1.0;IM/1.0"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "X-Akamai-SR-Hop: 1"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "True-Client-IP: 23.46.175.14"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-cache-remote-on"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-get-request-id"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-cache-remote-on"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-get-request-id"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-cache-remote-on"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Pragma: akamai-x-get-request-id"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "X-Akamai-CONFIG-LOG-DETAIL: true"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "TE: chunked;q=1.0"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Connection: TE"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Accept-Encoding: gzip"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Akamai-Origin-Hop: 2"
2023/09/22 02:00:15 [debug] 370030#370030: *1 http header: "Via: 1.1 c.v.image-server, 1.1 v1-akamaitech.net(ghost) (AkamaiGHost), 1.1 akamai.net(ghost) (AkamaiGHost)"