Hi, I'm still in the process of migration from channels 1 to channels 2... One thing I'm interested in is related to [ http://channels.readthedocs.io/en/latest/one-to-two.html#application-instances ] """ASGI applications are now instantiated once per socket and can use local variables on self to store information"""
So, we have an `AsyncJsonWebsocketConsumer` where websocket clients want to operate on a django model instance - each websocket mostly on the same object. With channels 1 we would always send with each message the `objID` - doing `obj=model.objects.get(pk=objID)` and read/write on `obj`. In channels 2 I could save the `objID` server side in the consumer class - like `self.objID` with one initial message like `set-obj-id`. For the ORM access I now have to do `obj = await database_sync_to_async( model.objects.get )(pk=self.objID)` QUESTION: Is is legitimate to store the "model instance itself" like `self.obj = await database_sync_to_async( model.objects.get )(pk=objID)` and keep that instance around for the lifetime of that socket -- doing some `await database_sync_to_async( self.obj.save )()` on some respective messages ? Note: multiple websockets might operate on the same obj/objID ! So my feeling is that would work as long as I keep testing with the `runserver` or in production as long as I know that I have only ONE PROCESS -- but in general the django caching mechanism might cause inconsistencies ... !? Another, somewhat related question is regarding a kind of "background routine" that I started to implement as an asyncio Task. Note: It was kind of tricky to realize that I needed `asyncio.ensure_future` to get it run asynchronously -- ref. https://stackoverflow.com/questions/48871831/django-channels-async-consumer-does-not-appear-to-execute-asynchronously Maybe that could be worked into the channels docs maybe here: http://channels.readthedocs.io/en/latest/topics/worker.html Since that "routine" should be able to be canceled and pauses (I'm using an asyncio.event) from any websocket consumer: QUESTION: What is the best place to store that Task object ? Again with `runserver` I can just use a global module-level `dict` to keep those Task objects. The whole async experience is really twisting my mind and interesting at the same time ;-) Regards, Sebastian -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/123c14e2-65c6-499e-9a27-b3a256aab099%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
