Websocket acting different on different client languages - flutter

Question

I have this Django Python Channels setup:
class MarketplaceConsumer(GenericAsyncAPIConsumer):
queryset = TestChannel.objects.all()
serializer_class = TestChannelSerializer
permission_classes = [permissions.AllowAny]
#model_observer(TestChannel)
async def comment_activity(self, message: TestChannelSerializer, observer=None, **kwargs):
await self.send_json(message.data)
#comment_activity.serializer
def comment_activity(self, instance: TestChannel, action, **kwargs) -> TestChannelSerializer:
'''This will return the comment serializer'''
return TestChannelSerializer(instance)
#action()
async def subscribe_to_comment_activity(self, user_pk, **kwargs):
print(user_pk) # PRINTS USER_PK PASSED THROUGH ACTION
await self.comment_activity.subscribe()
When this is run through JavaScript, I do get the expected result, the action prints the user_pk.
However, connecting to the same WebSocket using flutter, the user_pk is not printed, meaning the action specified is not even being called.
Am I implementing this incorrectly with the flutter client?
final channel = IOWebSocketChannel.connect(
Uri.parse('ws://127.0.0.1:8000/ws/marketplace/'));
#override
void initState() {
final data = json.encode({
'action': "subscribe_to_comment_activity",
'request_id': Helpers.generateId(),
'user_pk': 'PCs4o8c17xg',
});
channel.stream.listen((message) {
channel.sink.add(data);
//channel.sink.close(status.goingAway);
print(jsonDecode(message));
});
super.initState();
}

Answer 1

Figured this out! The flutter part somehow needs acknowledgement from the backend server. At least that's what I understand.
Adding an accept method to the backend works this out.
async def accept(self, **kwargs):
await super().accept(** kwargs)
print('connected')
await self.comment_activity.subscribe()