Take steps to avoid serving an outdated version of the interop category data

[DanielRyanSmith]

Upon releasing the Interop 2023 dashboard, some users were unable to see the page because the site would sometimes reference an older cached version of webapp/static/interop-data.json that did not have Interop 2023 category data. The file was renamed to ensure the latest version was referenced, but ideally this category data would be pulled from an endpoint rather than referenced in its current form to avoid this situation from happening again.

[foolip]

Do you know at what layer the caching was and whether the /api URLs are immune to the same problem?

[KyleJu]

Do you know at what layer the caching was and whether the /api URLs are immune to the same problem?

After some digging, it is caused by the GCP default cache for all static files, as shown by

The JSON filed lives under static/interop-data_v2.json. We have a default expiration for 24 hours for this type of cache. Ideally moving it out of the static file folder should solve the problem, or even put them in the wpt-interop Javascript. We also cache all the files served by the component handler. So as long as this file is not served through component handler API, having a separate API endpoint should work.

[jcscottiii]

Here's a possible improvement for this:
Add a query parameter with the app version to the static assets.

We do this in ChromeStatus. We can do the same thing for the template that renders interop.js. When the backend renders the page, the browser will cache “interop.js?v=VERSION” which will change between version deployments. As a result, it will retrieve the new version of interop.js for VERSION+1.

[racheljay]

I would like to take a look at this issue. To make sure I'm understanding correctly, we want to make sure that fetchYearData() is pulling the most recent data available and not the cached version of interop-data.json. Would it be a viable solution to export the JSON data to a .js file outside of /static and have fetchYearData() fetch data from that? Or would it be better to create an endpoint to populate the data directly?

[DanielRyanSmith]

Hello @racheljay! Thanks for the inquiry, and any help is welcome. From my understanding of @KyleJu's explanation of the specific cause of our problem, the most important requirement here is to move this data out of the webapp/static folder and have it live somewhere else, which would fix the GCP caching issue. This can be done in many ways, and the option you laid out should be sufficient. The prospect of pulling this information from an endpoint was just an initial idea of a possible way to avoid serving an outdated cached version of this file. I'll rename this issue accordingly.

[DanielRyanSmith]

Closing this now, as I believe we've addressed this to avoid it in the future. Thanks for the help @racheljay!