On Friday 07 April 2017 17:47:51 Carl Meyer wrote: > Hi Shai, > > On 04/07/2017 06:02 AM, Shai Berger wrote: > > This is an idea that came up during the djangocon-europe conference: Add > > the ability to install general instrumentation hooks around the database > > "execute" and "executemany" calls. > > > > Such hooks would allow all sorts of interesting features. For one, they > > could replace the current special-case allowing assertNumQueries & > > friends to record queries out of debug mode (it's an ugly hack, really), > > but they could also support my imagined use case -- a context-manager > > which could prevent database access during execution of some code (I'm > > thinking mostly of using it around "render()" calls and serialization, > > to make sure all database access is being done in the view). > > Another use-case is for preventing database access during tests unless > specifically requested by the test (e.g. pytest-django does this, > currently via monkeypatching). >
Yep. This feels right. > > My idea for implementation is to keep a thread-local stack of context- > > managers, and have them wrap each call of "execute". We could actually > > even use one such context-manager instead of the existing > > CursorDebugWrapper. > > Why a new thread-local instead of explicitly per-connection and stored > on the connection? > Sorry for implying that it would be a new thread-local, I just hadn't thought it through when I wrote this. Of course it goes on the (already thread-local) connection. Shai.
