Question

我才刚刚开始学习Django框架，而我从Django 2.0开始。我创建的只是一个简单的站点，并且创建了一个自定义管理器来获取处于“已发布”状态的所有对象。但是，当我添加此管理器时，它破坏了管理员站点的“保存/编辑/删除”功能，并为我提供了错误：

Manager isn't accessible via Post instances

帖子是我为其定义了自定义管理器的对象。（请原谅我，如果我不使用该术语）。对该错误的追溯也不是特别容易遵循。

一些希望能提供帮助的代码。

我的models.py文件中的客户经理

class PublishedManager(models.Manager):
    def get_queryset(self):
        return super(PublishedManager, self).get_queryset().filter(status='published')

在我的Post班中注册经理：

class Post(models.Model):
    ...

    objects = models.Manager()
    published = PublishedManager()
    tags = TaggableManager()

当我在published = PublishedManager()行中注释时，所有功能都恢复到管理站点。自定义管理器出了什么问题？除了默认管理器之外，我还需要告诉Django在某个地方使用它吗？我当然需要更多学习，但是这些使我发疯。谢谢大家！

跟踪：

Environment:
Request Method: POST
Request URL: http://localhost:8000/admin/blog/post/add/

Django Version: 2.0.6
Python Version: 3.6.4
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'blog',
 'taggit']
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:

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/core/handlers/exception.py" in inner
  35.             response = get_response(request)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/contrib/admin/options.py" in wrapper
  575.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/views/decorators/cache.py" in _wrapped_view_func
  44.         response = view_func(request, *args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/contrib/admin/sites.py" in inner
  223.             return view(request, *args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/contrib/admin/options.py" in add_view
  1554.         return self.changeform_view(request, None, form_url, extra_context)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapper
  62.             return bound_func(*args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/utils/decorators.py" in bound_func
  58.                 return func.__get__(self, type(self))(*args2, **kwargs2)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/contrib/admin/options.py" in changeform_view
  1451.             return self._changeform_view(request, object_id, form_url, extra_context)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/contrib/admin/options.py" in _changeform_view
  1483.             if form.is_valid():

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/forms/forms.py" in is_valid
  179.         return self.is_bound and not self.errors

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/forms/forms.py" in errors
  174.             self.full_clean()

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/forms/forms.py" in full_clean
  378.         self._post_clean()

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/forms/models.py" in _post_clean
  407.             self.validate_unique()

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/forms/models.py" in validate_unique
  416.             self.instance.validate_unique(exclude=exclude)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/db/models/base.py" in validate_unique
  952.         date_errors = self._perform_date_checks(date_checks)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/db/models/base.py" in _perform_date_checks
  1062.             date = getattr(self, unique_for)

File "/Users/jlahut/Programming/Python/django-blog/venv/lib/python3.6/site-packages/django/db/models/manager.py" in __get__
  178.             raise AttributeError("Manager isn't accessible via %s instances" % cls.__name__)

Exception Type: AttributeError at /admin/blog/post/add/
Exception Value: Manager isn't accessible via Post instances

定义自定义管理器时，Django 2.0管理员保存功能中断

0 个答案: