We used get_multi when preparing the proxies to decide which to
load from the database, but then sent multiple get requests to
Memcache to re-fetch the same data from that get_multi. Silly!
Use the data that's already stored on the proxy anyway.
This is a surprisingly huge performance gain. On my testing (with
cache_classes set to true to also cache templates), this sped up
closet_hangers#index rendering by a factor of 2 when there were a
significant number of items. Cool beans.
I think we can even hold off on the individual hanger caching now:
we've made the closet hanger partial tons faster by moving forms out
of them and doing this cache check earlier. I'm expecting significant
performance gains both here and on items#index (though less so there).
I'll deploy and see how much it helps in production; if not enough, we
can look at the layered caching of hangers, lists, groups, full pages,
etc.
So glad we don't *have* to move to a pagination model!
In particular, pet#load was handling locale-switching itself, but wasn't
switching back to original locale on error. We could've used a rescue
block, but, when I18n.with_locale is so cool, may as well use it fully.
This one was actually pretty darn clever - nobody's abused it, but
I was reading a blog post where someone described this type of
issue, I realized it was a brilliant attack, and then realized
DTI was vulnerable. Oops. Thanks for the solution, Jamie!
http://jamie-wong.com/2012/08/22/what-i-did-at-khan-academy/#XSS+Fix
