Comment by danburzo
2 months ago
Good call! Honestly I just wanted to wrap it up before the holidays, but you’re right that a small section on Vary would have been useful.
Things like non-conforming caching services made me punt actual suggestions to a later article, as I wasn’t sure how my sense of the RFC interacted with the real world. HTTP Caching Tests seems like a great resource for this, but only includes Fastly out of the big providers, and it seems to be doing okay with Vary. https://cache-tests.fyi/
Updated the article with some information on the `Vary` and `No-Vary-Search` headers. I’ve left out the details of how revalidation works with `Vary` since I haven’t been able to reconcile yet what the spec seems to encourage vs what the tests on cache-tests.fyi suggest is conformant behavior.