New chat message notification Django Channels

I've got Django Channels 2.1.2 set up in my Django app by following a tutorial and now need to set up a notification system for new messages. I want to do this in the simplest way possible (ideally using native Django features if possible...etc Django templating).

I've looked around the internet but there isn't a clear tutorial/explanation anywhere for doing this with Django Channels.

One answer on here said

For notifications you only need two models: User and Notification. On connect set the scope to the currently authenticated user. Set up a post_save signal on your Notification model to trigger a consumer method to message the notification object's user. –

I am struggling to wrap my head around what this would look like, I already have a User model but no Notification one.

Would I have a signals.py in my chat app which looked something like

@receiver(post_save, sender=User)
def create_notification(sender, instance, created, **kwargs):
    if created:
        Notification.objects.create(user=instance)

What would the front end look like? This is obviously all in-app and not via emails.

Would I save any instances of the Notification model (generated by post_save signals.py) to my database and then render out that figure using Django templating in the top corner of the webpage for example?

Appreciate any help!

My Django Channels code is below!

consumers.py

class ChatConsumer(AsyncConsumer):
    async def websocket_connect(self, event):
        print('connected', event)

        other_user = self.scope['url_route']['kwargs']['username']
        me = self.scope['user']
        #print(other_user, me)
        thread_obj = await self.get_thread(me, other_user)
        self.thread_obj = thread_obj
        chat_room = f"thread_{thread_obj.id}"
        self.chat_room = chat_room
        # below creates the chatroom
        await self.channel_layer.group_add(
            chat_room,
            self.channel_name
        )

        await self.send({
            "type": "websocket.accept"
        })

    async def websocket_receive(self, event):
        # when a message is recieved from the websocket
        print("receive", event)
        front_text = event.get('text', None)
        if front_text is not None:
            loaded_dict_data = json.loads(front_text)
            msg =  loaded_dict_data.get('message')
            user = self.scope['user']
            username = 'default'
            if user.is_authenticated:
                username = user.username
            myResponse = {
                'message': msg,
                'username': username,
            }
            await self.create_chat_message(user, msg)

            # broadcasts the message event to be sent, the group send layer
            # triggers the chat_message function for all of the group (chat_room)
            await self.channel_layer.group_send(
                self.chat_room,
                {
                    'type': 'chat_message',
                    'text': json.dumps(myResponse)
                }
            )
    # chat_method is a custom method name that we made
    async def chat_message(self, event):
        # sends the actual message
        await self.send({
                'type': 'websocket.send',
                'text': event['text']
        })

    async def websocket_disconnect(self, event):
        # when the socket disconnects
        print('disconnected', event)

    @database_sync_to_async
    def get_thread(self, user, other_username):
        return Thread.objects.get_or_new(user, other_username)[0]

    @database_sync_to_async
    def create_chat_message(self, me, msg):
        thread_obj = self.thread_obj
        return ChatMessage.objects.create(thread=thread_obj, user=me, message=msg)

models

class ThreadManager(models.Manager):
    def by_user(self, user):
        qlookup = Q(first=user) | Q(second=user)
        qlookup2 = Q(first=user) & Q(second=user)
        qs = self.get_queryset().filter(qlookup).exclude(qlookup2).distinct()
        return qs

    # method to grab the thread for the 2 users
    def get_or_new(self, user, other_username): # get_or_create
        username = user.username
        if username == other_username:
            return None, None
        # looks based off of either username
        qlookup1 = Q(first__username=username) & Q(second__username=other_username)
        qlookup2 = Q(first__username=other_username) & Q(second__username=username)
        qs = self.get_queryset().filter(qlookup1 | qlookup2).distinct()
        if qs.count() == 1:
            return qs.first(), False
        elif qs.count() > 1:
            return qs.order_by('timestamp').first(), False
        else:
            Klass = user.__class__
            try:
                user2 = Klass.objects.get(username=other_username)
            except Klass.DoesNotExist:
                user2 = None
            if user != user2:
                obj = self.model(
                        first=user,
                        second=user2
                    )
                obj.save()
                return obj, True
            return None, False

class Thread(models.Model):
    first        = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='chat_thread_first')
    second       = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='chat_thread_second')
    updated      = models.DateTimeField(auto_now=True)
    timestamp    = models.DateTimeField(auto_now_add=True)

    objects      = ThreadManager()

    def __str__(self):
        return f'{self.id}'

    @property
    def room_group_name(self):
        return f'chat_{self.id}'

    def broadcast(self, msg=None):
        if msg is not None:
            broadcast_msg_to_chat(msg, group_name=self.room_group_name, user='admin')
            return True
        return False

class ChatMessage(models.Model):
    thread      = models.ForeignKey(Thread, null=True, blank=True, on_delete=models.SET_NULL)
    user        = models.ForeignKey(settings.AUTH_USER_MODEL, verbose_name='sender', on_delete=models.CASCADE)
    message     = models.TextField()
    timestamp   = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f'{self.id}'

views.py

class InboxView(LoginRequiredMixin, ListView):
    template_name = 'chat/inbox.html'
    context_object_name = 'threads'
    def get_queryset(self):
        return Thread.objects.by_user(self.request.user).exclude(chatmessage__isnull=True).order_by('timestamp')
        # by_user(self.request.user)

class ThreadView(LoginRequiredMixin, FormMixin, DetailView):
    template_name = 'chat/thread.html'
    form_class = ComposeForm
    success_url = '#'

    def get_queryset(self):
        return Thread.objects.by_user(self.request.user)

    def get_object(self):
        other_username  = self.kwargs.get("username")
        obj, created    = Thread.objects.get_or_new(self.request.user, other_username)
        if obj == None:
            raise Http404
        return obj

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context['form'] = self.get_form()
        return context

    def post(self, request, *args, **kwargs):
        if not request.user.is_authenticated:
            return HttpResponseForbidden()
        self.object = self.get_object()
        form = self.get_form()
        if form.is_valid():
            return self.form_valid(form)
        else:
            return self.form_invalid(form)

    def form_valid(self, form):
        thread = self.get_object()
        user = self.request.user
        message = form.cleaned_data.get("message")
        ChatMessage.objects.create(user=user, thread=thread, message=message)
        return super().form_valid(form)

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