AttributeError：“ DatabaseWrapper”对象没有属性“ Database”

Question

Version numbers are Django 1.6, Python 3.3.2 and Mac OS X 10.9

I create an app with this command

 python3 manage.py startapp lists

Then in my lists/tests.py file I put this code

from django.test import TestCase

class SmokeTest(TestCase):

 def test_bad_maths(self):
    self.assertEqual(1 + 1, 3)

then I run this command from the app root folder

python3 manage.py test

and this is the stack trace that comes back, it's not working correctly

    E

         ======================================================================
ERROR: test_bad_maths (lists.tests.SmokeTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 124, in ensure_connection
    self.connect()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 111, in connect
    conn_params = self.get_connection_params()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 85, in get_connection_params
    raise NotImplementedError
NotImplementedError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 653, in supports_transactions
    self.connection.enter_transaction_management()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 288, in enter_transaction_management
    if managed == self.get_autocommit():
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 324, in get_autocommit
    self.ensure_connection()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 124, in ensure_connection
    self.connect()
  File "/usr/local/lib/python3.3/site-packages/django/db/utils.py", line 86, in __exit__
    db_exc_type = getattr(self.wrapper.Database, dj_exc_type.__name__)
AttributeError: 'DatabaseWrapper' object has no attribute 'Database'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 124, in ensure_connection
    self.connect()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 111, in connect
    conn_params = self.get_connection_params()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 85, in get_connection_params
    raise NotImplementedError
NotImplementedError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.3/site-packages/django/test/testcases.py", line 178, in __call__
    self._pre_setup()
  File "/usr/local/lib/python3.3/site-packages/django/test/testcases.py", line 749, in _pre_setup
    self._fixture_setup()
  File "/usr/local/lib/python3.3/site-packages/django/test/testcases.py", line 861, in _fixture_setup
    if not connections_support_transactions():
  File "/usr/local/lib/python3.3/site-packages/django/test/testcases.py", line 848, in connections_support_transactions
    for conn in connections.all())
  File "/usr/local/lib/python3.3/site-packages/django/test/testcases.py", line 848, in <genexpr>
    for conn in connections.all())
  File "/usr/local/lib/python3.3/site-packages/django/utils/functional.py", line 49, in __get__
    res = instance.__dict__[self.func.__name__] = self.func(instance)
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 664, in supports_transactions
    self.connection.leave_transaction_management()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 317, in leave_transaction_management
    if managed == self.get_autocommit():
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 324, in get_autocommit
    self.ensure_connection()
  File "/usr/local/lib/python3.3/site-packages/django/db/backends/__init__.py", line 124, in ensure_connection
    self.connect()
  File "/usr/local/lib/python3.3/site-packages/django/db/utils.py", line 86, in __exit__
    db_exc_type = getattr(self.wrapper.Database, dj_exc_type.__name__)
AttributeError: 'DatabaseWrapper' object has no attribute 'Database'

----------------------------------------------------------------------
Ran 0 tests in 0.031s

FAILED (errors=1)

Answer 1

I have exact the same environment: * Mac OS X 10.9 * Python 3.3.2 * Django 1.6

I have virtualenv 1.10.1 installed and create one, install django and create the project and app:

virtualenv-3.3 tt
cd tt
. bin/activate
pip install django==1.6
django-admin.py startproject myproj
cd myproj
chmod +x manage.py
./manage.py startapp lists

Now I pasted your code into lists/test.py and run the test with the default settings.py (database sqlite3, etc.)

./manage.py test

and got the right results:

Creating test database for alias 'default'...

F
======================================================================
FAIL: test_bad_maths (lists.tests.SmokeTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/erevilla/tt/myproj/lists/tests.py", line 6, in test_bad_maths
    self.assertEqual(1 + 1, 3)
AssertionError: 2 != 3

----------------------------------------------------------------------
Ran 1 test in 0.001s

FAILED (failures=1)
Destroying test database for alias 'default'...

I can't reproduce your problem. Please check:

• settings.py (what database are you using)
• manage.py (for incorrect version)
• DJANGO_SETTINGS_MODULE is undefined