Question

我正在使用django-channels在后端组织我的websocket。现在，一切正常，除了当db中的信息更改时发送到前端的消息之外。有http端点可以更改模型。

这是我的网络套接字消费者

import asyncio
from asgiref.sync import async_to_sync, sync_to_async
from channels.generic.websocket import AsyncJsonWebsocketConsumer
from rest_framework.response import Response
from rest_framework import status
from channels.db import database_sync_to_async

# models and serializers

from billing.models import Billing
from billing.serializers import BillingSerializer
from customers.models import Customer
from customers.serializers import CustomersSerializer
from shipping.models import Shipping
from shipping.serializers import ShippingSerializer

from .models import Order
from .serializers import OrdersSerializer
from .views import OrdersViewSet

from .exceptions import ClientError
from .utils import get_orders_or_error, get_orders_or_warning


class OrdersConsumer(AsyncJsonWebsocketConsumer):

    async def connect(self):

        orders = await get_orders_or_warning()

        if 'user' in self.scope:
            await self.close()
        else:
            await self.accept()

        self.orders = set(orders)
        # await self.create_order(content)

    async def receive_json(self, content):
        command = content.get('command', None)

        orders = await get_orders_or_warning()
        # print(list(self.orders))
        # print(set(orders))

        try:
            if command == "join":
                await self.join_room(JWT_Token=content['token'])
            elif command == "leave":
                await self.leave_room()
            elif command == "send":
                await self.send_room(content['message'])
        except ClientError as e:
            await self.send_json({"error": e.code})

    async def disconnect(self, code):
        for room_id in list(self.rooms):
            try:
                self.send_json({
                    'type': 'CLOSE',
                    'message': "Socket closed"
                })
                await self.leave_room(content['token'])
            except ClientError:
                pass

    async def join_room(self, JWT_Token):
        orders = await get_orders_or_warning()
        serializer = OrdersSerializer(orders, many=True)
        # print('serializer', serializer)

        if self.orders != set(orders):
            await self.send_json(
                {
                    'type': 'orders',
                    'data': json.dumps(serializer.data),
                },
            )

        await self.send_json(
            {
                'type': 'orders',
                'data': json.dumps(serializer.data),
            },
        )

    async def leave_room(self, JWT_Token):

        await self.channel_layer.group_send(
            orders.group_name,
            {
                'type': 'orders.leave',
                'JWT_Token': JWT_Token
            }
        )

        self.rooms.discard()

        await self.channel_layer.group_discard(
            orders.group_name,
            self.channel_name
        )

        await self.send_json({
            "leave": str(room_id),
        })

    async def send_room(self, message):
        if room_id not in self.rooms:
            raise ClientError("ROOM_ACCESS_DENIED")

        orders = await get_orders_or_warning()
        serializer = OrdersSerializer(orders, many=True)

        await self.send_json(
            {
                'type': 'orders.give',
                'data': json.dumps(serializer.data)
            }
        )
        await self.send(text_data=json.dumps({
            'message': message
        }))

    async def orders_leave(self, event):
        await self.send_json(
            {
                'type': 'LEAVE',
                'room': event["room_id"],
                'username': event["username"]
            }
        )

这是我的路由文件


application = ProtocolTypeRouter({
    'websocket': (
            URLRouter([
                url('orders/', OrdersConsumer),
            ])
    )
})

当某些更改发生时，我想通过前端获取所有数据。当前的消费者可以这样做吗？如果是的话，怎么办？我看了太多我想的信息源，现在我有点困惑我实际上该怎么做。

如果可能的话，我不想重写结构。如果您能解释我为什么以及为什么需要按照您所说的方式写它，我将非常感激

Answer 1

您可以使用信号来监视更改，并使用how to interact with the consumer from the outside上的文档中定义的方法向消费者发送消息

Django通道在模型更改时发送消息

1 个答案: