Breaks Django Contrib Session Tests (CacheSessionTests, CacheDBSessionTests, etc....) about django-redis HOT 5 CLOSED

Hi! Thanks for your report! It seems that redis does not expires inmediatelly cache keys with negative timeouts.
I need some time for investigate about it.

In any case, I used it in many projects for store session and it works without any problems.

Thanks.

from django-redis.

No problem, thanks for your fast reply.

On Tue, Sep 17, 2013 at 2:55 PM, Andrey Antukh [email protected]:

Hi! Thanks for your report! It seems that redis does not expires
inmediatelly cache keys with negative timeouts.
I need some time for investigate it.

In any case, I used it in many projects for store session and it works
without any problems.

Thanks.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/44#issuecomment-24625806
.

Dakin Sloss
cell: (314) 265-2271
[email protected]

from django-redis.

Hmm, this seems not a django-redis bug, because a django backend does not handle it well on session cache backend.

On the original django session test:

self.session.set_expiry(-timedelta(seconds=10))

set_expiry method set '_session_expiry' key on the cache that is not used never in load session data... is very strange but django-redis can not do any thing with this if session backend not setups in a properly way cache expiration timeout.

from django-redis.

Thees seems not django-redis problem. And, django-redis is used in produccion as sessions storage in various projects and work well.

from django-redis.

I just walked through this (I got sick of seeing the failing tests) and confirmed that it does appear to be a django-redis issue. By default, django-redis assumes that all timeouts that are not positive signal for the key to not have a timeout.

I've got a detailed explanation of why everything happens in a gist: https://gist.github.com/kevin-brown/9238166

Essentially the issue is that django-redis treats all negative timeouts as permanent, which at one point it didn't do. Django expects that negative timeouts when saving will prevent the save from happening. If this sounds like something that should be fixed, I can make a PR that fixes the issue.

from django-redis.