无效的base64编码的字符串：数据字符的数目217不能为1大于4的倍数

如何解决无效的base64编码的字符串：数据字符的数目217不能为1大于4的倍数

我正在学习django，并使用它创建一个todo应用。同时设置django rest框架api。我收到一个异常错误。我使用django已有一段时间，但之前从未遇到过相同的错误。我不知道为什么会出现这个错误。

当我第一次执行命令manage.py runserver并导航到用户时，就会发生该错误

错误如下

Invalid base64-encoded string: number of data characters (217) cannot be 1 more than a multiple of 4
Request Method: GET
Request URL:    http://127.0.0.1:8001/users/
Django Version: 3.1
Exception Type: Error
Exception Value:    
Invalid base64-encoded string: number of data characters (217) cannot be 1 more than a multiple of 4
Exception Location: /usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/base64.py,line 87,in b64decode
Python Executable:  /Users/yogendrakumar/PycharmProjects/todo_app/bin/python
Python Version: 3.8.5
Python Path:    
['/Users/yogendrakumar/PycharmProjects/todo_app','/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python38.zip','/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8','/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/lib-dynload','/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages']
Server time:    Sat,29 Aug 2020 12:25:01 +0530

views.py

from django.contrib.auth.models import User,Group
from rest_framework import viewsets
from rest_framework import permissions
from todo.serializers import UserSerializer,GroupSerializer


class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer
    permission_classes = [permissions.IsAuthenticated]


class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer
    permission_classes = [permissions.IsAuthenticated]

以下是追溯：

Environment:


Request Method: GET
Request URL: http://127.0.0.1:8001/users/

Django Version: 3.1
Python Version: 3.8.5
Installed Applications:
['django.contrib.admin','django.contrib.auth','django.contrib.contenttypes','django.contrib.sessions','django.contrib.messages','django.contrib.staticfiles','rest_framework','todo']
Installed Middleware:
['django.middleware.security.SecurityMiddleware','django.contrib.sessions.middleware.SessionMiddleware','django.middleware.common.CommonMiddleware','django.middleware.csrf.CsrfViewMiddleware','django.contrib.auth.middleware.AuthenticationMiddleware','django.contrib.messages.middleware.MessageMiddleware','django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback (most recent call last):
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",line 215,in _get_session
    return self._session_cache

During handling of the above exception ('SessionStore' object has no attribute '_session_cache'),another exception occurred:
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",line 118,in decode
    return signing.loads(session_data,salt=self.key_salt,serializer=self.serializer)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/core/signing.py",line 135,in loads
    base64d = TimestampSigner(key,salt=salt).unsign(s,max_age=max_age).encode()
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/core/signing.py",line 201,in unsign
    result = super().unsign(value)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/core/signing.py",line 184,in unsign
    raise BadSignature('Signature "%s" does not match' % sig)

During handling of the above exception (Signature "xnqTuv_ylPs2HNImqZUFHZYYDRY5IfETbWXc5_4zbB8" does not match),another exception occurred:
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/core/handlers/exception.py",line 47,in inner
    response = get_response(request)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/core/handlers/base.py",line 179,in _get_response
    response = wrapped_callback(request,*callback_args,**callback_kwargs)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/views/decorators/csrf.py",line 54,in wrapped_view
    return view_func(*args,**kwargs)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/viewsets.py",line 114,in view
    return self.dispatch(request,*args,**kwargs)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/views.py",line 505,in dispatch
    response = self.handle_exception(exc)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/views.py",line 465,in handle_exception
    self.raise_uncaught_exception(exc)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/views.py",line 476,in raise_uncaught_exception
    raise exc
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/views.py",line 493,in dispatch
    self.initial(request,line 410,in initial
    self.perform_authentication(request)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/views.py",line 324,in perform_authentication
    request.user
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/request.py",line 220,in user
    self._authenticate()
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/request.py",line 373,in _authenticate
    user_auth_tuple = authenticator.authenticate(self)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/rest_framework/authentication.py",line 123,in authenticate
    if not user or not user.is_active:
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/utils/functional.py",line 240,in inner
    self._setup()
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/utils/functional.py",line 376,in _setup
    self._wrapped = self._setupfunc()
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/auth/middleware.py",line 23,in <lambda>
    request.user = SimpleLazyObject(lambda: get_user(request))
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/auth/middleware.py",line 11,in get_user
    request._cached_user = auth.get_user(request)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/auth/__init__.py",line 174,in get_user
    user_id = _get_user_session_key(request)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/auth/__init__.py",line 58,in _get_user_session_key
    return get_user_model()._meta.pk.to_python(request.session[SESSION_KEY])
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",line 65,in __getitem__
    return self._session[key]
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",in _get_session
    self._session_cache = self.load()
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/db.py",line 44,in load
    return self.decode(s.session_data) if s else {}
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",line 122,in decode
    return self._legacy_decode(session_data)
  File "/Users/yogendrakumar/PycharmProjects/todo_app/lib/python3.8/site-packages/django/contrib/sessions/backends/base.py",line 126,in _legacy_decode
    encoded_data = base64.b64decode(session_data.encode('ascii'))
  File "/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/base64.py",in b64decode
    return binascii.a2b_base64(s)

Exception Type: Error at /users/
Exception Value: Invalid base64-encoded string: number of data characters (217) cannot be 1 more than a multiple of 4

serializers.py

from django.contrib.auth.models import User,Group
from rest_framework import serializers


class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ['url','username','email','groups']


class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        fields = ['url','name']

解决方法

我遇到了同样的问题，但是当我的Django版本为3.0.8并将其升级到3.1时，我得到了错误消息

,

真的不知道为什么，但是从浏览器中清除 cookie 可以解决问题。

,

随时清除浏览器缓存和 cookie。

,

从DJANGO_SESSION表中删除所有旧会话

,

我忘记激活我的virtualenv并收到此错误，因为我正在使用错误的Django版本运行此项目 所以我激活并解决了

,

清除浏览器缓存，然后重试。 ：）