Unsubscribe from consumer issue

[hishnash]

Discussed in #196

^{Originally posted by Ilyes-git January 28, 2024}
Hello everyone,

I'm new to channels, I've tried to follow the readme to the letter, but I still haven't managed to solve part of the problem.
My goal is simple, "I want to have the ability, to receive messages in real time for the logged in user."

To give you some context, let me share with you my current code:

class Message(models.Model):
    sender = models.ForeignKey(User, on_delete=models.CASCADE, related_name="sent_messages")
    receiver = models.ForeignKey(User, on_delete=models.CASCADE, related_name="received_messages")
    message = models.CharField(max_length=1000)
    datetime = models.DateTimeField(auto_now_add=True)

class MessageSerializer(serializers.ModelSerializer):
    class Meta:
        model = Message
        fields = ALL_FIELDS

# consumers.py
from chat_app.models import Message
from chat_app.serializers import MessageSerializer
from djangochannelsrestframework.decorators import action
from djangochannelsrestframework.generics import GenericAsyncAPIConsumer
from djangochannelsrestframework.observer import model_observer


class MessageConsumer(GenericAsyncAPIConsumer):
    queryset = Message.objects.all()
    serializer_class = MessageSerializer

    @model_observer(Message)
    async def message_activity(
        self,
        message: MessageSerializer,
        observer=None,
        **kwargs,
    ):
        await self.send_json(message)

    @message_activity.groups_for_signal
    def message_activity(self, instance: Message, **kwargs):
        yield f"-user-{instance.receiver.id}"

    @message_activity.groups_for_consumer
    def message_activity(self, receiver, list=False, **kwargs):
        # receiver = self.scope["user"].id # => AttributeError: 'ModelObserver' object has no attribute 'scope'
        yield f"-user-{receiver}"

    @action()
    async def subscribe_to_send_messages(self, **kwargs):
        if "user" in self.scope and self.scope["user"].is_authenticated:
            await self.message_activity.subscribe(receiver=self.scope["user"].id)
            return {}, 201

    @action()
    async def unsubscribe_from_send_messages(self, **kwargs):
        await self.message_activity.unsubscribe(receiver=self.scope["user"].id)
        return {}, 204

Actions :

• subscribe_to_send_messages works perfectly 👌
• unsubscribe_from_send_messages doesn't work 🙁

Question :
1 - in @message_activity.groups_for_consumer decorator I tried to use self.scope like mentioned on the documentation, but it doesn't seem to work (maybe the doc isn't up to date?).
2 - The big issue for me : How to make unsubscribe_from_send_messages work, am I making a mistake somewhere?

Thanks in advance for your help 🙏

Sources:
https://djangochannelsrestframework.readthedocs.io/en/latest/examples/filtered_model_observer.html
https://nilcoalescing.com/blog/BuildingARealtimeSocialNetworkUsingDjangoChannels/