[Support] Camo service is not respecting Cache-Control.

[OoLunar]

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Hello! I just finished making a URL route tracker, intended to be used to see how many times a specific user/repository has been viewed. While there are numerous flaws with execution and ultimately may not be useful, at the end of the day the funny monkey's brain does like seeing numbers go up.

On my GitHub profile is an example of the route tracker being used:

However, when refreshing, the funny number does not go up. When reloading the page, I double checked to ensure that my browser (Firefox) was clearing it's cache (DevTools -> Networking -> Disable Cache). After checking GitHub's Camo documentation, I see that it's supposed to respect the Cache-Control header. When inspecting the request with curl -i 'https://cloudflare-route-tracker.oolunar.workers.dev/github/oolunar?style=flat-square&label=Profile%20Views&color=6b73db&logo=github&logoEmbed', I can see that the cache-control header is set as instructed and the number does increment within the response.

Likewise, when doing curl -i 'https://camo.githubusercontent.com/37a8fa74afe0eb3fb5138432c29497f66eb99501cce1d5e30e98e5535a5c0a4f/68747470733a2f2f636c6f7564666c6172652d726f7574652d747261636b65722e6f6f6c756e61722e776f726b6572732e6465762f6769746875622f6f6f6c756e61723f7374796c653d666c61742d737175617265266c6162656c3d50726f66696c65253230566965777326636f6c6f723d366237336462266c6f676f3d676974687562266c6f676f456d626564', the number was not being incremented. Interestingly, it was returning two numbers: 153,221 and 153,220 I'm going to blame this on cache.

As the Camo docs instructed, I did try purging the cache: curl -i -X PURGE '$url', which returned the following response:

HTTP/2 200 
content-type: application/json
accept-ranges: bytes
date: Fri, 11 Apr 2025 07:35:54 GMT
x-varnish: 2547908950
via: 1.1 varnish
x-served-by: cache-stl760082-STL
content-length: 50

{ "status": "ok", "id": "760082-1743233251-8772" }

After making the request multiple times, the response was now returning either 153,223 or 153,222.

Is there anything I'm doing wrong here, or is this something out of my control? The code for the URL tracker can be found here: https://github.com/OoLunar/CloudflareRouteTracker/blob/1e7c92ea2b693500f4e53d90822a1dd3308fd649/src/index.ts, I apologize for the messy code. The service is hosted as a Cloudflare worker and the behavior is working as expected when I access the resource directly.

[Arizard]

I'm getting a similar issue to you. Mine will finally forward the request after a minute or so, which causes the counter to update.

[queenofcorgis]

@SayedSadiq45

We’ve clarified our stance on using generative AI tools like ChatGPT within our Community via this announcement. Please review the guidelines to ensure your post meets them as failure to adhere to those rules can result in action taken by our moderator team.  You can read our updated Code of Conduct and the announcement for more details. Thank you for helping us maintain an authentic and beneficial space for everyone.

[Arizard]

I figured out a solution by reverse engineering the badges this guy built: https://github.com/antonkomarev

I added this to my nginx config to set these specific headers:

add_header Cache-Control "max-age=0, no-cache, no-store, must-revalidate";

for some reason, no-cache doesn't work on it's own, perhaps I understand it wrong.

screenshot of it working on my profile:

now it will update on each page refresh, at least for me. How will it handle high traffic? not sure 😊

[OoLunar]

Thank you for sharing this! Was this documented anywhere else or should docs be updated?