Cache middleware should cache HEAD requests

[eratothene]

When conditional get middleware was responsible for HEAD request, the side effects of incorrect middleware ordering could cause striped responses to be cached that is why HEAD requests, where not cached before.
Now HEAD requests content stripping is guarunteed to came after every middleware (applied in responce fixes) so it is safe to cache HEAD request now.

[eratothene]

Comment on why I have deleted the method check completely: request method is checked in process_request, hence there is no need to check it again.

[arien]

Yeah, that'd be nice to have.

One note about the patch: instead of removing the check for the HTTP method, IMHO it'd be better to factor out the logic for deciding if the cache could be used (the not request.method in ('GET', 'HEAD') or request.GET in process_request) and use that in both process_request and process_response.

[arien]

Hmm, never mind the last comment; I think I was looking at an earlier version of your patch(?). request._cache_update_cache would now be the central point deciding whether or not to use the cache.

[Julien Phalip]

3 years later, this is no longer relevant as CacheMiddleware does not discriminate between request methods any more.