KeyError: 'DATABASE_URL' (maybe a 0.4.2 regression?)

Thanks for your work on django-environ.

My project works fine with 0.4.1, but breaks in 0.4.2, released this morning.

I’m using Python 3.4.2 on Debian 8 and Django 1.10 in a virtualenv. I checked in a couple of ways that yes, my DATABASE_URL variable was being loaded properly. In particular, I added a line in my settings file, print(os.environ['DATABASE_URL']), immediately prior to my env.db() call, and it printed my setting as I expected.

If this is not a regression, then perhaps some upgrade docs would be in order so I know what I need to change in my project to use the latest django-environ.

Thanks!

(env3) ipmetadataretention@host:~$ manage.py shell
Traceback (most recent call last):
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 265, in get_value
    value = self.ENVIRON[var]
KeyError: 'DATABASE_URL'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/core/management/base.py", line 305, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/core/management/base.py", line 348, in execute
    saved_locale = translation.get_language()
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/utils/translation/__init__.py", line 190, in get_language
    return _trans.get_language()
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/utils/translation/__init__.py", line 57, in __getattr__
    if settings.USE_I18N:
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 53, in __getattr__
    self._setup(name)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 41, in _setup
    self._wrapped = Settings(settings_module)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 97, in __init__
    mod = importlib.import_module(self.SETTINGS_MODULE)
  File "/usr/lib/python3.4/importlib/__init__.py", line 109, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 2254, in _gcd_import
  File "<frozen importlib._bootstrap>", line 2237, in _find_and_load
  File "<frozen importlib._bootstrap>", line 2226, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1200, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1129, in _exec
  File "<frozen importlib._bootstrap>", line 1471, in exec_module
  File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
  File "/usr/share/ip-metadata-retention/django/ipmetadataretention/settings/production.py", line 2, in <module>
    from .common import *  # noqa: F401, F403
  File "/usr/share/ip-metadata-retention/django/ipmetadataretention/settings/common.py", line 87, in <module>
    'default': env.db(),
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 196, in db_url
    return self.db_url_config(self.get_value(var, default=default), engine=engine)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 269, in get_value
    raise ImproperlyConfigured(error_msg)
django.core.exceptions.ImproperlyConfigured: Set the DATABASE_URL environment variable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 265, in get_value
    value = self.ENVIRON[var]
KeyError: 'DATABASE_URL'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/share/ip-metadata-retention/django/manage.py", line 23, in <module>
    execute_from_command_line(sys.argv)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
    utility.execute()
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/core/management/__init__.py", line 359, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/core/management/base.py", line 317, in run_from_argv
    connections.close_all()
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/db/utils.py", line 229, in close_all
    for alias in self:
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/db/utils.py", line 223, in __iter__
    return iter(self.databases)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/utils/functional.py", line 35, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/db/utils.py", line 156, in databases
    self._databases = settings.DATABASES
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 53, in __getattr__
    self._setup(name)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 41, in _setup
    self._wrapped = Settings(settings_module)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/django/conf/__init__.py", line 97, in __init__
    mod = importlib.import_module(self.SETTINGS_MODULE)
  File "/usr/lib/python3.4/importlib/__init__.py", line 109, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 2254, in _gcd_import
  File "<frozen importlib._bootstrap>", line 2237, in _find_and_load
  File "<frozen importlib._bootstrap>", line 2226, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1200, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1129, in _exec
  File "<frozen importlib._bootstrap>", line 1471, in exec_module
  File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
  File "/usr/share/ip-metadata-retention/django/ipmetadataretention/settings/production.py", line 2, in <module>
    from .common import *  # noqa: F401, F403
  File "/usr/share/ip-metadata-retention/django/ipmetadataretention/settings/common.py", line 87, in <module>
    'default': env.db(),
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 196, in db_url
    return self.db_url_config(self.get_value(var, default=default), engine=engine)
  File "/var/lib/ipmetadataretention/env3/lib/python3.4/site-packages/environ/environ.py", line 269, in get_value
    raise ImproperlyConfigured(error_msg)
django.core.exceptions.ImproperlyConfigured: Set the DATABASE_URL environment variable

[joke2k]

I’m looking for a solution, but probably I’ve to revert on #105.

[joke2k]

Reverted and released.

I was trying to convert the Env.ENVIRON variable into a set of dictionaries, with os.environ as first item as default, in order to allow to use a cascade dicts into Env.get_value.

But I postpone this feature for 0.5

If anyone is interested to discuss about that… we can met on freenode#python