我试图显示连接到相同 websocket 的当前用户(在我的例子中是聊天室)，但我有一个小问题。我想创建一个变量来存储用户并将其通过 websockets 发送到我的前端，我已经实现了这一点，但问题在于。
Consumers.py - 方法 1
class ChatRoomConsumer(AsyncWebsocketConsumer):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.users: list = []
@database_sync_to_async
def create_msg(self, user_id=None, message=None, room=None):
if user_id is not None:
sender = User.objects.get(id=user_id)
msg = Message.objects.create(
author=sender, message=message, room_name=room)
msg.save()
return msg
else:
get_msgs = Message.objects.filter(room_name__in=[room])
serializer = MessageSerializer(get_msgs, many=True)
return serializer.data
async def connect(self):
self.room_name = self.scope['url_route']['kwargs']['room_name']
self.room_group_name = f'chat_{self.room_name}'
self.messages = await self.create_msg(room=self.room_name)
await self.channel_layer.group_add(
self.room_group_name,
self.channel_name
)
await self.accept()
await self.send(text_data=json.dumps({
'db_messages': self.messages,
}))
async def disconnect(self, close_code):
print(close_code)
await self.channel_layer.group_discard(
self.room_group_name,
self.channel_name
)
async def receive(self, text_data):
text_data_json = json.loads(text_data)
type = text_data_json['type']
message = text_data_json['message']
username = text_data_json['username']
user_id = text_data_json['user_id']
self.user_id = text_data_json['user_id']
if type == 'chatroom_message':
self.msg = await self.create_msg(user_id, message, self.room_name)
await self.channel_layer.group_send(
self.room_group_name, {
'type': type,
'message': message,
'username': username,
'user_id': user_id
}
)
async def chatroom_message(self, event):
message = event['message']
username = event['username']
await self.send(text_data=json.dumps({
'message': message,
'username': username,
}))
# nefunkcni ukazatel momentalnich uzivatelu v mistnosti
async def get_user(self, event):
print('get_user called')
if event['message'] == 'disconnect':
print('remove', event['username'])
try:
self.users.remove(event['username'])
except ValueError:
print('user already removed')
else:
if event['username'] not in self.users:
self.users.append(event['username'])
print(self.users)
await self.send(text_data=json.dumps({
'users': self.users
}))
通过这种方法，它仅在第一个进入聊天的用户的 View 中正确显示当前登录的用户，其他用户看不到，因此在他们之前加入的用户就在那里。 在这种方法中，我在构造函数中定义变量users。
Consumers.py - 方法 2
from channels.generic.websocket import AsyncWebsocketConsumer
from channels.db import database_sync_to_async
from .models import Message
from .serializers import MessageSerializer
from django.contrib.auth.models import User
from django.db.models import Prefetch
from django.core.serializers.json import DjangoJSONEncoder
from asgiref.sync import sync_to_async, async_to_sync
import channels
import json
users: list = []
class ChatRoomConsumer(AsyncWebsocketConsumer):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
#self.users: list = []
@database_sync_to_async
def create_msg(self, user_id=None, message=None, room=None):
if user_id is not None:
sender = User.objects.get(id=user_id)
msg = Message.objects.create(
author=sender, message=message, room_name=room)
msg.save()
return msg
else:
get_msgs = Message.objects.filter(room_name__in=[room])
serializer = MessageSerializer(get_msgs, many=True)
return serializer.data
async def connect(self):
self.room_name = self.scope['url_route']['kwargs']['room_name']
self.room_group_name = f'chat_{self.room_name}'
self.messages = await self.create_msg(room=self.room_name)
await self.channel_layer.group_add(
self.room_group_name,
self.channel_name
)
await self.accept()
await self.send(text_data=json.dumps({
'db_messages': self.messages,
}))
async def disconnect(self, close_code):
print(close_code)
await self.channel_layer.group_discard(
self.room_group_name,
self.channel_name
)
async def receive(self, text_data):
text_data_json = json.loads(text_data)
type = text_data_json['type']
message = text_data_json['message']
username = text_data_json['username']
user_id = text_data_json['user_id']
self.user_id = text_data_json['user_id']
if type == 'chatroom_message':
self.msg = await self.create_msg(user_id, message, self.room_name)
await self.channel_layer.group_send(
self.room_group_name, {
'type': type,
'message': message,
'username': username,
'user_id': user_id
}
)
async def chatroom_message(self, event):
message = event['message']
username = event['username']
await self.send(text_data=json.dumps({
'message': message,
'username': username,
}))
# nefunkcni ukazatel momentalnich uzivatelu v mistnosti
async def get_user(self, event):
print('get_user called')
if event['message'] == 'disconnect':
print('remove', event['username'])
try:
users.remove(event['username'])
except ValueError:
print('user already removed')
else:
if event['username'] not in users:
users.append(event['username'])
print(users)
await self.send(text_data=json.dumps({
'users': users
}))
在此方法中，用户可以正确显示，但不是来自当前房间的用户(它显示来自所有其他房间的用户)。这有点合乎逻辑，因为变量的声明位于顶层。
但我的问题是我应该在哪里声明它？当它位于构造函数中时，它始终会覆盖当前用户之前所在房间的用户，而当它位于顶层时，它会获取所有房间中的所有用户。
最佳答案
如果您还没有找到答案，这是我的 2 美分:
消费者是单例的，这意味着每个 channel (websocket 连接)都有一个实例。所以这可能是消费者类中存在用户的问题。
另一种方法是为用户提供字典，而不是数组。所以你可以拥有每个房间的 key ，如下所示:
users = { "room_1": [], "room_2": [] }
我知道我的答案中没有代码，但我希望它可以作为您解决方案的指南!
关于python - Django Channels 显示房间中的当前用户，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/71460004/