HEAD clobbers GET cache

[jayvdb]

Mixing HEAD and GET requests for the same URL does not work. This isnt enabled by default, but afaics any use of the cacheable_methods to be anything other than GET will problematic.

This is a similar problem to POST #211 , and it is also solved in requests-cache because it uses a key which includes the method.

At the moment, invalidating_methods should include PATCH and POST. The former definitely invalidates the cache, and a POST to a URL are very likely to mean a cached value for GET of that URL will be outdated.

[woodruffw]

Looks like PATCH was added with #221, so I think the current invalidating_methods set is now (more) complete.

Someone raised a similar problem in #337, and I've come to a similar conclusion as you: setting cacheable_methods to anything besides GET is almost certainly going to result in incorrect or at least subtly spec-violating responses.

[woodruffw]

Per last comment, the invalidation bit of this is addressed with #211 and the cacheable_methods part is under discussion in #337, so I'll close this out in favor of the newer issue 🙂