本文介绍了Django返回UserLazyObject:TypeError:字段'id'需要一个数字，但< channels.auth.UserLazyObject对象的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在按照教程使用Django Channels创建聊天应用程序.在我的代码中，我为模型提供了一个自定义管理器.这是经理:
I'm using Django Channels to make a chat app following a tutorial. in my code I have a custom manager for my models. here is the manager:
from import models
from django.db.models import Count
class ThreadManager(models.Manager):
def get_or_create_personal_thread(self, user1, user2):
threads = self.get_queryset().filter(thread_type='personal')
threads = threads.filter(users__in=[user1, user2]).distinct()
threads = threads.annotate(u_count=Count('users')).filter(u_count=2)
if threads.exists():
return threads.first()
else:
thread = self.create(thread_type='personal')
thread.users.add(user1)
thread.users.add(user2)
return thread
def by_user(self, user):
return self.get_queryset().filter(users__in=[user])
问题是，当我在消费者中引入模型类时，出现了这个陌生的错误:TypeError:int()参数必须是字符串，类似字节的对象或数字，而不是'UserLazyObject'
the problem is that when i introduce the model class in my consumer, I get this unfamiliar error:TypeError: int() argument must be a string, a bytes-like object or a number, not 'UserLazyObject'
什么是UserLazyObject?周围有什么办法吗?
what is a UserLazyObject ?and is there any way around it?
这是我的consumer.py:下面的这一行代码介绍了该模型，对其进行注释或取消注释会一次又一次地删除或重新引入该错误.
here is my consumer.py: the model is introduce by this line of code below, commenting it or uncommenting it removes or reintroduces the error again and again.
thread_obj = Thread.objects.get_or_create_personal_thread(me, other_user)
from channels.consumer import SyncConsumer
from asgiref.sync import async_to_sync
from chat.models import Thread
from django.contrib.auth.models import User
class ChatConsumer(SyncConsumer):
def websocket_connect(self, event):
# get the two users
me = self.scope['user']
other_username = self.scope['url_route']['kwargs']['username']
other_user = User.objects.get(username=other_username)
# get or create incase
thread_obj = Thread.objects.get_or_create_personal_thread(me, other_user)
self.room_name = 'presonal_thread_'
async_to_sync(self.channel_layer.group_add)(self.room_name, self.channel_name)
self.send({
'type': 'websocket.accept'
})
print(f'[{self.channel_name}] - connected now')
def websocket_receive(self, event):
print(f'[{self.channel_name}] - received now {event["text"]}')
async_to_sync(self.channel_layer.group_send)(
self.room_name,
{
'type': 'websocket.message',
'text': event.get('text')
}
)
def websocket_message(self, event):
print(f'[{self.channel_name}] - sent now {event["text"]}')
self.send({
'type': 'websocket.send',
'text': event.get('text')
})
def websocket_disconnect(self, event):
print(f'[{self.channel_name}] - disconnected now')
async_to_sync(self.channel_layer.group_discard)(self.room_name, self.channel_name)
和models.py
and the models.py
from chat.managers import ThreadManager
from django.db import models
class TrackingModel(models.Model):
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Meta:
abstract = True
class Thread(TrackingModel):
THREAD_TYPE = (
('personal', 'Personal'),
('group', 'Group')
)
name = models.CharField(max_length=50, null=True, blank=True)
thread_type = models.CharField(max_length=15, choices=THREAD_TYPE, default='group')
users = models.ManyToManyField('auth.User')
objects = ThreadManager()
def __str__(self) -> str:
if self.thread_type == 'personal' and self.users.count() == 2:
return f'{self.users.first()} and {self.users.last()}'
return f'{self.name}'
class Message(TrackingModel):
thread = models.ForeignKey(Thread, on_delete=models.CASCADE)
sender = models.ForeignKey('auth.User', on_delete=models.CASCADE)
text = models.TextField(blank=False, null=False)
def __str__(self) -> str:
return f'From <Thread - {self.thread}>'
这是我的routing.py:
here is my routing.py:
from channels.routing import ProtocolTypeRouter, URLRouter
from django.urls import path
from chat.consumers import EchoConsumer, ChatConsumer
from channels.auth import AuthMiddlewareStack
application = ProtocolTypeRouter({
'websocket': AuthMiddlewareStack(
URLRouter([
path('ws/chat/<str:username>/', ChatConsumer.as_asgi()),
path('ws/chat/', EchoConsumer.as_asgi() ),
])
),
})
和我的views.py:
and my views.py:
from django.shortcuts import render
from django.views import View
from django.contrib.auth import get_user_model
from django.shortcuts import Http404
from chat.models import Thread, Message
class ThreadView(View):
template_name = 'chat/chat.html'
def get_queryset(self):
return Thread.objects.by_user(self.request.user)
def get_object(self):
other_username = self.kwargs.get("username")
self.other_user = get_user_model().objects.get(username=other_username)
obj = Thread.objects.get_or_create_personal_thread(self.request.user, self.other_user)
if obj == None:
raise Http404
return obj
def get_context_data(self, **kwargs):
context = {}
context['me'] = self.request.user
context['thread'] = self.get_object()
context['user'] = self.other_user
context['messages'] = self.get_object().message_set.all()
return context
def get(self, request, **kwargs):
context = self.get_context_data(**kwargs)
return render(request, self.template_name, context=context)
def post(self, request, **kwargs):
self.object = self.get_object()
thread = self.get_object()
data = request.POST
user = request.user
text = data.get("message")
Message.objects.create(sender=user, thread=thread, text=text)
context = self.get_context_data(**kwargs)
return render(request, self.template_name, context=context)
这是完整的追溯:
(myenv) ➜ chat_demo git:(master) ✗ python manage.py runserver
Watching for file changes with StatReloader
Performing system checks...
System check identified no issues (0 silenced).
December 21, 2020 - 14:51:36
Django version 3.1.4, using settings 'chat_demo.settings'
Starting ASGI/Channels version 3.0.2 development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
HTTP GET /chat/kelly1/ 200 [1.57, 127.0.0.1:49479]
WebSocket HANDSHAKING /ws/chat/kelly1/ [127.0.0.1:49482]
Exception inside application: Field 'id' expected a number but got <channels.auth.UserLazyObject object at 0x1086c5e50>.
Traceback (most recent call last):
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 1774, in get_prep_value
return int(value)
TypeError: int() argument must be a string, a bytes-like object or a number, not 'UserLazyObject'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/staticfiles.py", line 44, in __call__
return await self.application(scope, receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/routing.py", line 71, in __call__
return await application(scope, receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/sessions.py", line 47, in __call__
return await self.inner(dict(scope, cookies=cookies), receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/sessions.py", line 254, in __call__
return await self.inner(wrapper.scope, receive, wrapper.send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/auth.py", line 181, in __call__
return await super().__call__(scope, receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/middleware.py", line 26, in __call__
return await self.inner(scope, receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/routing.py", line 150, in __call__
return await application(
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/consumer.py", line 94, in app
return await consumer(scope, receive, send)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/consumer.py", line 58, in __call__
await await_many_dispatch(
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/utils.py", line 51, in await_many_dispatch
await dispatch(result)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/asgiref/sync.py", line 304, in __call__
ret = await asyncio.wait_for(future, timeout=None)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/asyncio/tasks.py", line 455, in wait_for
return await fut
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/concurrent/futures/thread.py", line 57, in run
result = self.fn(*self.args, **self.kwargs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/db.py", line 13, in thread_handler
return super().thread_handler(loop, *args, **kwargs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/asgiref/sync.py", line 343, in thread_handler
return func(*args, **kwargs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/channels/consumer.py", line 125, in dispatch
handler(message)
File "/Users/kelly/Desktop/programms/djchat/chat_demo/chat/consumers.py", line 13, in websocket_connect
thread_obj = Thread.objects.get_or_create_personal_thread(me, other_user)
File "/Users/kelly/Desktop/programms/djchat/chat_demo/chat/managers.py", line 8, in get_or_create_personal_thread
threads = threads.filter(users__in=[user1, user2]).distinct()
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/query.py", line 942, in filter
return self._filter_or_exclude(False, *args, **kwargs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/query.py", line 962, in _filter_or_exclude
clone._filter_or_exclude_inplace(negate, *args, **kwargs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/query.py", line 969, in _filter_or_exclude_inplace
self._query.add_q(Q(*args, **kwargs))
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/sql/query.py", line 1358, in add_q
clause, _ = self._add_q(q_object, self.used_aliases)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/sql/query.py", line 1377, in _add_q
child_clause, needed_inner = self.build_filter(
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/sql/query.py", line 1319, in build_filter
condition = self.build_lookup(lookups, col, value)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/sql/query.py", line 1165, in build_lookup
lookup = lookup_class(lhs, rhs)
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/lookups.py", line 24, in __init__
self.rhs = self.get_prep_lookup()
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/fields/related_lookups.py", line 59, in get_prep_lookup
self.rhs = [target_field.get_prep_value(v) for v in self.rhs]
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/fields/related_lookups.py", line 59, in <listcomp>
self.rhs = [target_field.get_prep_value(v) for v in self.rhs]
File "/Users/kelly/Desktop/programms/djchat/myenv/lib/python3.8/site-packages/django/db/models/fields/__init__.py", line 1776, in get_prep_value
raise e.__class__(
TypeError: Field 'id' expected a number but got <channels.auth.UserLazyObject object at 0x1086c5e50>.
WebSocket DISCONNECT /ws/chat/kelly1/ [127.0.0.1:49482]
任何帮助将不胜感激.提前致谢我现在已经编辑了问题，以包括完整的回溯
any help will be highly appreciated. thanks in advanceI have now edited the question to include the full traceback
推荐答案
频道的源代码显示("> https://github.com/django/channels/blob/4ddf6e70f34790fb7131a10fc5af285dcdc3dcbeb1/channels/auth.py#L139 ):
The source code of channels shows (https://github.com/django/channels/blob/4ddf6e70f34790fb7131a10fc5af285dc3dcbeb1/channels/auth.py#L139):
class UserLazyObject(LazyObject):
"""
Throw a more useful error message when scope['user'] is accessed before
it's resolved
"""
def _setup(self):
raise ValueError("Accessing scope user before it is ready.")
，这里是范围的填充方式( https://github.com/django/channels/blob/4ddf6e70f34790fb7131a10fc5af285dcdc3dcbeb1/channels/auth.py#L155 ):
and here is how the scope is populated (https://github.com/django/channels/blob/4ddf6e70f34790fb7131a10fc5af285dc3dcbeb1/channels/auth.py#L155):
def populate_scope(self, scope):
# Make sure we have a session
if "session" not in scope:
raise ValueError(
"AuthMiddleware cannot find session in scope. "
"SessionMiddleware must be above it."
)
# Add it to the scope if it's not there already
if "user" not in scope:
scope["user"] = UserLazyObject()
async def resolve_scope(self, scope):
scope["user"]._wrapped = await get_user(scope)
要在代码中解决该问题，您将不得不使用以下内容(未经测试-可能需要异步/等待处理):
To resolve it in your code, you would have to use something along these lines (untested - might need async/await handling):
if isinstance(user, UserLazyObject):
user._setup()
user = user._wrapped
从SimpleLazyObject解析用户的原始Django代码供参考(来自我的非渠道代码的工作示例):
Original Django code resolving a user from SimpleLazyObject for reference (working example from my non-channels code):
if isinstance(user, SimpleLazyObject):
user._setup()
user = user._wrapped
这篇关于Django返回UserLazyObject:TypeError:字段'id'需要一个数字，但< channels.auth.UserLazyObject对象的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！