Why do I get 'ImproperlyConfigured' exception, implying circular imports? - django

Question

I have had this issue before, but I've managed to find the circular import being referenced. I face it again, but I can't find the problem.
My project's name is 'sare', and my sare/urls.py looks like this:
from django.contrib import admin
from django.urls import include, path
urlpatterns = [
path('users/', include('users.urls', namespace='users')),
path('admin/', admin.site.urls),
]
And users/urls.py is this:
from django.urls import path
from .views import UsersTableView#, UserCreateView, UserUpdateView, UserDeleteView
app_name = 'users'
urlpatterns = [
path('table/', UsersTableView.as_view(), name='users_table'),
# path('create/', UserCreateView.as_view(), name='users_create'),
# path('update/<int:pk>', UserUpdateView.as_view(), name='users_update'),
# path('delete/<int:pk>', UserDeleteView.as_view(), name='users_delete'),
]
The only piece of code that is not commented in my views is the UsersTableView, that looks like this:
from django.contrib.auth.mixins import LoginRequiredMixin, UserPassesTestMixin
from .models import CustomUser
from .tables import UsersTable
from .filters import UserFilter
from .form_helpers import UsersFilterFormHelper
from django.views.generic import CreateView, UpdateView, DeleteView
from .forms import UserForm
from django.urls import reverse_lazy, reverse
from django_tables2.export import ExportMixin
from django_tables2 import RequestConfig,SingleTableView,Table as TableBase
from django_filters import FilterSet
class InitUserMixin(object):
def __init__(self, *args, **kwargs):
self.user = kwargs.pop("user", None)
super(InitUserMixin, self).__init__(*args, **kwargs)
class FilterUserMixin(InitUserMixin, FilterSet):
pass
class Table(InitUserMixin, TableBase):
pass
class PagedFilteredTableView(ExportMixin, SingleTableView):
filter_class = None
formhelper_class = None
context_filter_name = 'filter'
def get_queryset(self, **kwargs):
qs = super(PagedFilteredTableView, self).get_queryset()
self.filter = self.filter_class(self.request.GET, queryset=qs, user=self.request.user)
self.filter.form.helper = self.formhelper_class()
return self.filter.qs
def get_table(self, **kwargs):
table = super(PagedFilteredTableView, self).get_table(user=self.request.user)
RequestConfig(self.request, paginate={'page': self.kwargs.get('page', 1),
"per_page": self.paginate_by}).configure(table)
return table
def get_context_data(self, **kwargs):
context = super(PagedFilteredTableView, self).get_context_data(**kwargs)
context[self.context_filter_name] = self.filter
return context
class UsersTableView(LoginRequiredMixin,PagedFilteredTableView, UserPassesTestMixin):
model = CustomUser
table_class = UsersTable
template_name = 'users/users_table.html'
paginate_by = 10
filter_class = UserFilter
formhelper_class = UsersFilterFormHelper
def test_func(self):
if self.request.user.is_superuser:
return True
else:
return False
I've tried to comment everything in the view and just write pass, but it gives the same result.
I cannot see any circular import. Do you see anything wrong with this code, or something else I should check out?
Traceback (most recent call last):
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\threading.py", line 916, in _bootstrap_inner
self.run()
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\threading.py", line 864, in run
self._target(*self._args, **self._kwargs)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\utils\autoreload.py", line 53, in wrapper
fn(*args, **kwargs)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\management\commands\runserver.py", line 117, in inner_run
self.check(display_num_errors=True)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\management\base.py", line 395, in check
include_deployment_checks=include_deployment_checks,
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\management\base.py", line 382, in _run_checks
return checks.run_checks(**kwargs)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
new_errors = check(app_configs=app_configs)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\checks\urls.py", line 13, in check_url_config
return check_resolver(resolver)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\core\checks\urls.py", line 23, in check_resolver
return check_method()
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\urls\resolvers.py", line 406, in check
for pattern in self.url_patterns:
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\utils\functional.py", line 48, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "C:\Users\Iván\AppData\Local\Programs\Python\Python36\Lib\site-packages\django\urls\resolvers.py", line 596, in url_patterns
raise ImproperlyConfigured(msg.format(name=self.urlconf_name))
django.core.exceptions.ImproperlyConfigured: The included URLconf 'sare.urls' does not appear to have any patterns in it. If you see valid patterns in the file then the issue is probably caused by a circular import.
EDIT:
My settings.py is this:
import os
# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.0/howto/deployment/checklist/
# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = '^*5r6l%i-dubv_ur*p06d*rp#d#*dg#4z%&li8#f4ca=h9z-r*'
# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True
ALLOWED_HOSTS = []
# Application definition
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'rest_framework.authtoken',
'sare',
'formats',
'users',
'crequest',
'django_tables2',
'django_filters',
#'allauth', # registration
#'allauth.account', # registration
#'allauth.socialaccount', # registration
]
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',
]
ROOT_URLCONF = 'sare.urls'
TEMPLATES = [
{
'BACKEND': 'django.template.backends.django.DjangoTemplates',
'DIRS': [],
'APP_DIRS': True,
'OPTIONS': {
'context_processors': [
'django.template.context_processors.debug',
'django.template.context_processors.request',
'django.contrib.auth.context_processors.auth',
'django.contrib.messages.context_processors.messages',
],
},
},
]
WSGI_APPLICATION = 'sare.wsgi.application'
# Database
# https://docs.djangoproject.com/en/3.0/ref/settings/#databases
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}
# Password validation
# https://docs.djangoproject.com/en/3.0/ref/settings/#auth-password-validators
AUTH_PASSWORD_VALIDATORS = [
{
'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
},
]
# Internationalization
# https://docs.djangoproject.com/en/3.0/topics/i18n/
LANGUAGE_CODE = 'en-us'
TIME_ZONE = 'UTC'
USE_I18N = True
USE_L10N = True
USE_TZ = True
# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.0/howto/static-files/
STATIC_URL = '/static/'
AUTH_USER_MODEL = 'users.CustomUser'

Answer 1

Watch out for the MRO (method resolution order) in your view class UsersTableView(LoginRequiredMixin, PagedFilteredTableView, UserPassesTestMixin), the mixins should always be at the beginning of hierarchy to be taken into account.
Otherwise, to see what would be the circular import, we would need the content of the following files:
models.py
tables.py
filters.py
form_helpers.py
forms.py
Or you can try to debug it yourself:
simply launch a python interpreter in your project
import sare.urls or import sare.views
it should give a ImportError, a more precise clue as to where the circular import is

Answer 2

Are you importing UsersTableView properly and defined it? it seems your use case is pretty beginner level of Django so I suggest check the Django class-based views and URLs docs again and check your code accordingly.