问题描述
似乎我正在按照说明进行操作，但不知何故 Django 没有将 django_countries 视为应用程序。
错误：
System check identified no issues (0 silenced).
February 18,2021 - 23:56:01
Django version 3.1.4,using settings 'django_project.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
Exception in thread django-main-thread:
Traceback (most recent call last):
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/utils/module_loading.py",line 13,in import_string
module_path,class_name = dotted_path.rsplit('.',1)
ValueError: not enough values to unpack (expected 2,got 1)
The above exception was the direct cause of the following exception:
(Wsgi stuff...)
settings.py:
INSTALLED_APPS = [
'django_countries','registration.apps.RegistrationConfig',.....
项目树：
.
├── db.sqlite3
├── django_project
│ ├── asgi.py
│ ├── __init__.py
│ ├── __pycache__
│ ├── settings.py
│ ├── urls.py
│ └── wsgi.py
├── manage.py
├── myapp
│ ├── admin.py
│ ├── apps.py
│ ├── forms.py
│ ├── __init__.py
│ ├── migrations
│ ├── models.py
│ ├── __pycache__
│ ├── static
│ ├── templates
│ ├── tests.py
│ ├── urls.py
│ └── views.py
├── readme.rst
├── registration
│ ├── admin.py
│ ├── apps.py
│ ├── __init__.py
│ ├── migrations
│ ├── models.py
│ ├── __pycache__
│ ├── static
│ ├── templates
│ ├── tests.py
│ ├── urls.py
│ └── views.py
├── requirements.txt
├── static
│ └── project
├── templates
│ └── project.html
└── venv
├── bin
├── include
├── lib
├── lib64 -> lib
└── pyvenv.cfg
我用 pip 安装了它，使用 virtualenv。我的虚拟机处于活动状态，我可以使用 pip list 进行检查，以及使用我用来运行 django (python manage.py runserver) 的相同解释器导入 django-countries。无论如何，在 django 模型中，我可以清楚地导入和使用 django-countries (pycharm)。
怎么了？
解决方法
我认为我真正应该做的是删除这个问题。但是，一个人必须承认自己的白痴，所以....
显然我最初是这样做的，但从未注意到：
MIDDLEWARE = [
.... middlewares....
'django_countries',]
我收到错误消息，因此认为这是 venv 问题并为此项目重新安装了我的虚拟环境。然后我正确地将它添加到已安装的应用程序中，而不是中间件部分：
INSTALLED_APPS = [
'django_countries','registration.apps.RegistrationConfig',.....
但是由于 Django 导入中间件的过程仍在尝试导入一些绝对不是中间件的东西，并且导入的语法错误，因此在启动时失败并显示完整的堆栈跟踪：
xception in thread django-main-thread:
Traceback (most recent call last):
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/utils/module_loading.py",line 15,in import_string
module_path,class_name = dotted_path.rsplit('.',1)
ValueError: not enough values to unpack (expected 2,got 1)
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/servers/basehttp.py",line 45,in get_internal_wsgi_application
return import_string(app_path)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/utils/module_loading.py",line 19,in import_string
module = import_module(module_path)
File "/usr/lib/python3.9/importlib/__init__.py",line 127,in import_module
return _bootstrap._gcd_import(name[level:],package,level)
File "<frozen importlib._bootstrap>",line 1030,in _gcd_import
File "<frozen importlib._bootstrap>",line 1007,in _find_and_load
File "<frozen importlib._bootstrap>",line 986,in _find_and_load_unlocked
File "<frozen importlib._bootstrap>",line 680,in _load_unlocked
File "<frozen importlib._bootstrap_external>",line 790,in exec_module
File "<frozen importlib._bootstrap>",line 228,in _call_with_frames_removed
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/django_project/wsgi.py",line 16,in <module>
application = get_wsgi_application()
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/wsgi.py",line 13,in get_wsgi_application
return WSGIHandler()
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/handlers/wsgi.py",in __init__
self.load_middleware()
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/handlers/base.py",line 40,in load_middleware
middleware = import_string(middleware_path)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/utils/module_loading.py",line 17,in import_string
raise ImportError("%s doesn't look like a module path" % dotted_path) from err
ImportError: django_countries doesn't look like a module path
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/lib/python3.9/threading.py",line 954,in _bootstrap_inner
self.run()
File "/usr/lib/python3.9/threading.py",line 892,in run
self._target(*self._args,**self._kwargs)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/utils/autoreload.py",line 53,in wrapper
fn(*args,**kwargs)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py",line 138,in inner_run
handler = self.get_handler(*args,**options)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/contrib/staticfiles/management/commands/runserver.py",line 27,in get_handler
handler = super().get_handler(*args,**options)
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py",line 65,in get_handler
return get_internal_wsgi_application()
File "/run/media/fv/hdd-1/PROJECTS/django-receipes/django_template/venv/lib/python3.9/site-packages/django/core/servers/basehttp.py",line 47,in get_internal_wsgi_application
raise ImproperlyConfigured(
django.core.exceptions.ImproperlyConfigured: WSGI application 'django_project.wsgi.application' could not be loaded; Error importing module.