python - Django DB Settings 'Improperly Configured' Error

Question

Django (1.5) is workin' fine for me, but when I fire up the Python interpreter (Python 3) to check some things, I get the weirdest error when I try importing - from django.contrib.auth.models import User -

Traceback (most recent call last):
  File "/usr/local/lib/python3.2/dist-packages/django/conf/__init__.py", line 36, in _setup
    settings_module = os.environ[ENVIRONMENT_VARIABLE]
  File "/usr/lib/python3.2/os.py", line 450, in __getitem__
    value = self._data[self.encodekey(key)]
KeyError: b'DJANGO_SETTINGS_MODULE'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/dist-packages/django/contrib/auth/models.py", line 8, in <module>
    from django.db import models
  File "/usr/local/lib/python3.2/dist-packages/django/db/__init__.py", line 11, in <module>
    if settings.DATABASES and DEFAULT_DB_ALIAS not in settings.DATABASES:
  File "/usr/local/lib/python3.2/dist-packages/django/conf/__init__.py", line 52, in __getattr__
    self._setup(name)
  File "/usr/local/lib/python3.2/dist-packages/django/conf/__init__.py", line 45, in _setup
    % (desc, ENVIRONMENT_VARIABLE))

django.core.exceptions.ImproperlyConfigured: Requested setting DATABASES, 
  but settings are not configured. You must either define the environment 
  variable DJANGO_SETTINGS_MODULE or call settings.configure() 
  before accessing settings.

How could it be improperly configured, when it works fine outside the Python interpreter? In my Django settings, the DATABASES settings are:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': 'django_db', # Or path to database file if using sqlite3.
        # The following settings are not used with sqlite3:
        'USER': 'zamphatta',
        'PASSWORD': 'mypassword91',
        'HOST': '', # Empty for localhost through domain sockets or '127.0.0.1' for localhost through TCP.
        'PORT': '', # Set to empty string for default.
    }
}

...how is this improperly configured?

Answer 1

You can't just fire up Python and check things, Django doesn't know what project you want to work on. You have to do one of these things:

• Use python manage.py shell
• Use django-admin.py shell --settings=mysite.settings (or whatever settings module you use)
• Set DJANGO_SETTINGS_MODULE environment variable in your OS to mysite.settings

• (This is removed in Django 1.6) Use setup_environ in the python interpreter:

  from django.core.management import setup_environ
  from mysite import settings
  
  setup_environ(settings)
  

Naturally, the first way is the easiest.