Django 1.7 升级错误：AppRegistryNotReady：模型尚未加载答案

【问题标题】：Django 1.7 upgrade error: AppRegistryNotReady: Models aren't loaded yetDjango 1.7 升级错误：AppRegistryNotReady：模型尚未加载
【发布时间】：2014-10-30 02:35:03
【问题描述】：

我正在尝试将项目从 Django 1.6 升级到 1.7。到目前为止，我已经创建了一个具有所有相同安装的新 virtualenv，并将 Django 版本升级到新版本。我需要从 South 升级，但这样做时出错，所以我想我最初只是尝试 runserver，但我收到以下错误：

Traceback (most recent call last):
      File "manage.py", line 10, in <module>
        execute_from_command_line(sys.argv)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/core/management/__init__.py", line 385, in execute_from_command_line
        utility.execute()
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/core/management/__init__.py", line 354, in execute
        django.setup()
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/__init__.py", line 21, in setup
        apps.populate(settings.INSTALLED_APPS)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/apps/registry.py", line 108, in populate
        app_config.import_models(all_models)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/apps/config.py", line 197, in import_models
        self.models_module = import_module(models_module_name)
      File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
        __import__(name)
      File "/Users/Name/Dev/tps/products/models.py", line 127, in <module>
        watson.register(Product.objects.exclude(productimage=None))
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/manager.py", line 92, in manager_method
        return getattr(self.get_queryset(), name)(*args, **kwargs)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/query.py", line 698, in exclude
        return self._filter_or_exclude(True, *args, **kwargs)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/query.py", line 707, in _filter_or_exclude
        clone.query.add_q(~Q(*args, **kwargs))
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/sql/query.py", line 1287, in add_q
        clause, require_inner = self._add_q(where_part, self.used_aliases)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/sql/query.py", line 1314, in _add_q
        current_negated=current_negated, connector=connector)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/sql/query.py", line 1138, in build_filter
        lookups, parts, reffed_aggregate = self.solve_lookup_type(arg)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/sql/query.py", line 1076, in solve_lookup_type
        _, field, _, lookup_parts = self.names_to_path(lookup_splitted, self.get_meta())
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/sql/query.py", line 1339, in names_to_path
        field, model, direct, m2m = opts.get_field_by_name(name)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/options.py", line 416, in get_field_by_name
        cache = self.init_name_map()
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/options.py", line 445, in init_name_map
        for f, model in self.get_all_related_m2m_objects_with_model():
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/options.py", line 563, in get_all_related_m2m_objects_with_model
        cache = self._fill_related_many_to_many_cache()
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/db/models/options.py", line 577, in _fill_related_many_to_many_cache
        for klass in self.apps.get_models():
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/utils/lru_cache.py", line 101, in wrapper
        result = user_function(*args, **kwds)
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/apps/registry.py", line 168, in get_models
        self.check_models_ready()
      File "/Users/Name/.virtualenvs/test17/lib/python2.7/site-packages/django/apps/registry.py", line 131, in check_models_ready
        raise AppRegistryNotReady("Models aren't loaded yet.")
    django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet.

任何想法可能导致错误以及如何修复它？

【问题讨论】：

您是否从已安装的应用程序中删除了南？
是的，我按照这里的步骤操作：link，但我仍然收到错误
注意：我正在使用 django-allauth，并且对该应用程序中的迁移执行相同的操作，不确定这是否会导致问题。
在执行 runserver 或使用 manage.py 进行任何操作时，我反复收到此错误。这是在成功升级到 1.7 之后很久。原来与此无关，而是我复制了一堆代码以供参考，并留在了 models.py 文件的底部

标签： django django-1.7

【解决方案1】：

问题出在这一行（“/Users/Name/Dev/tps/products/models.py”，第 127 行）：

watson.register(Product.objects.exclude(productimage=None))

您尝试在导入时引用模型。在 Django 1.7 中不再可能。 Django 1.7 允许您仅在加载所有应用程序后使用您的模型。您应该将此调用移至AppConfig 的ready 回调，如下所示：

from django.apps import AppConfig


class ProductsConfig(AppConfig):
    name = 'products'

    def ready(self):
        Product = self.get_model('Product')
        watson.register(Product.objects.exclude(productimage=None))

那么您应该在您的products 应用程序的__init__.py 中引用此AppConfig：

default_app_config = 'products.apps.ProductsConfig'

其中apps 是您放置配置的模块的名称。

总体而言，由于这一变化，迁移到 Django 1.7 并不像人们想象的那么容易。以下是一些故障排除提示：https://docs.djangoproject.com/en/1.7/ref/applications/#troubleshooting

【讨论】：

谢谢 Vasily，我将尝试进行这些更改，并让您知道它们是如何进行的。这是第三方搜索应用 Watson，所以我猜他们需要在 1.7 版本中对其应用进行这些更改
太棒了，做到了！我在 Watson 注册了多个搜索，我把它们都放在那里。我只需要将“import Watson”添加到 apps.py
我收到此错误是因为我的 wsgi.py 文件已过期，django 1.7 对此有一种新格式，在使用 gunicorn 19.1.0 修复此问题后一切正常（19.1.1 已损坏）。 runserver 一切都很好，所以我只在产品部署中遇到了这个问题。
在执行 runserver 或使用 manage.py 进行任何操作时，我反复收到此错误。这是在成功升级到 1.7 之后很久。结果证明与此无关，而是我复制了一堆代码以供参考，并留在了 models.py 文件的底部。在 django 1.7 中，如果出现此错误，则错误可能在 models.py 某处

【解决方案2】：

当我将我的 django 项目模板更新到 1.7 时，我遇到了这个错误。改变的一件事是 wsgi.py 文件，因此需要一些更新。这是我的回溯：

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/gunicorn/workers/sync.py", line 93, in handle
    self.handle_request(listener, req, client, addr)
  File "/usr/local/lib/python2.7/dist-packages/gunicorn/workers/sync.py", line 134, in handle_request
    respiter = self.wsgi(environ, resp.start_response)
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/core/handlers/wsgi.py", line 168, in __call__
    self.load_middleware()
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/core/handlers/base.py", line 46, in load_middleware
    mw_instance = mw_class()
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/middleware/locale.py", line 23, in __init__
    for url_pattern in get_resolver(None).url_patterns:
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/core/urlresolvers.py", line 372, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/core/urlresolvers.py", line 366, in urlconf_module
    self._urlconf_module = import_module(self.urlconf_name)
  File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/home/kpmteam/staging/site/kpm/urls.py", line 7, in <module>
    admin.autodiscover()
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/contrib/admin/__init__.py", line 23, in autodiscover
    autodiscover_modules('admin', register_to=site)
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/utils/module_loading.py", line 67, in autodiscover_modules
    for app_config in apps.get_app_configs():
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/apps/registry.py", line 137, in get_app_configs
    self.check_apps_ready()
  File "/home/kpmteam/staging/deploys/20141029-115625/site/lib/django/apps/registry.py", line 124, in check_apps_ready
    raise AppRegistryNotReady("Apps aren't loaded yet.")
AppRegistryNotReady: Apps aren't loaded yet.

这就是 wsgi.py 文件的样子：

import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "settings")
import django.core.handlers.wsgi
application = django.core.handlers.wsgi.WSGIHandler()

现在（运行 Django 1.7 和 gunicorn 19.1.0）：

import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "settings")
from django.core.wsgi import get_wsgi_application
application = get_wsgi_application()

更改最后两行修复了它。请注意，您的 DJANGO_SETTINGS_MODULE 可能不同，通常是“project_name.settings”

【讨论】：

【解决方案3】：

我迟到了，但如果你使用 django-registration，你将不得不切换到 django-regitration-redux。

https://pypi.python.org/pypi/django-registration-redux/

看到这个答案：Django-registration compatibility issue with django 1.7

【讨论】：

【解决方案4】：

我找到了解决方案：

import django

django.setup()

【讨论】：