Thanks for the explanation! To get it working, I will replace my model converters with basic converters and do corresponding lookups in the views.
On Sunday, 20 June 2021 at 16:16:58 UTC-7 Andrew Godwin wrote: > Ah yes, that's because the URL parsing/conversion all happens in the main > (async, in ASGI mode) thread - and because to_python is a a synchronous > function interface, there is literally nothing you can do to make it work. > > The only real way of fixing this would be for Django to patch the URL > converters and run them all in a synchronous mode unless they were > decorated as "safe" somehow, much like we do for middleware. It's not a > terribly hard patch to make, but it does mean you don't have an immediate > solution. There are ways of trying to work around it, but they will all > result in you blocking the async thread while the ORM query runs, which > would be disastrous in production. > > My apologies for not getting this in for the original async view patch - I > had forgotten converters ran in the URL resolver. > > Andrew > > On Sat, Jun 19, 2021, at 12:31 AM, [email protected] wrote: > > > I'm trying to switch from WSGI to ASGI and I'm having issues with my model > id to model converters. > I define my converters like this > def to_python(self, primary_key): > try: > return self.model.objects.get(pk=primary_key) > except self.model.DoesNotExist: > raise ValueError > When I go to a url where a converter is used I get a > SynchronousOnlyOperation. > Seems like converters are executed in an async context. > If I use sync_to_async, I get a coroutine in my view instead of a model > instance. Awaiting it here would defeat the purpose of having a converter. > > Any ideas how to fix this? > > > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-users/ef60ed71-7f4f-482d-b540-bdf89e249aa4n%40googlegroups.com > > <https://groups.google.com/d/msgid/django-users/ef60ed71-7f4f-482d-b540-bdf89e249aa4n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/c130ef88-4dbf-42b9-a7b3-f0ba0b174a0an%40googlegroups.com.
