cache middleware should vary on full URL

[Jamey Sharp]

Standard HTTP cache behavior treats different URLs as different resources, but Django's cache middleware only generates cache keys based on request.get_full_path().

I believe that django.utils.cache._generate_cache_[header_]key should use request.build_absolute_uri() instead of request.get_full_path() so different hosts and schemes will get different cache entries.

I'm using Django 1.3 but as far as I can tell this hasn't changed as of today's git master.

[ludw]

This seems like a reasonable idea. Can't find any reasons why we shouldn't do this.

[Susan Tan]

PR is here: ​https://github.com/django/django/pull/1341 Feel free to code review. Thanks.

[Tim Graham]

This needs a test to demonstrate the change in behavior.

[Tim Graham]

Here's an updated PR with tests. I left some minor comments for improvement.

One concern is that upgrading Django will change cache keys for all the existing pages now that the domain name is part of the key. At a minimum, this needs to be documented in the release notes. Ideas for how we might be able to do this in a backwards compatible fashion would also be welcome.

[ijl]

I've documented the changes in the 1.7 release notes. I'm at a loss for backwards-compatible changes using the keys, given that existing cache keys use a hash.

[Tim Graham]

Docs still need some minor tweaks. Please uncheck "Patch needs improvement" when you have a chance to update it.

[Tim Graham <timograham@…>]

In 71a03e01aa19cbde08e915d156abf39b67d904ef:

Fixed #20346 -- Made cache middleware vary on the full URL.

Previously, only the URL path was included in the cache key.

Thanks jamey for the suggestion.