How to resolve “django.core.exceptions.ImproperlyConfigured: Application labels aren't unique, duplicates: foo” in Django 1.7?

Question

On upgrading to Django 1.7 I'm getting the following error message from ./manage.py

$ ./manage.py 
Traceback (most recent call last):
  File "./manage.py", line 16, in <module>
    execute_from_command_line(sys.argv)
  File "/home/johnc/.virtualenvs/myproj-django1.7/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 427, in execute_from_command_line
    utility.execute()
  File "/home/johnc/.virtualenvs/myproj-django1.7/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 391, in execute
    django.setup()
  File "/home/johnc/.virtualenvs/myproj-django1.7/local/lib/python2.7/site-packages/django/__init__.py", line 21, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/home/johnc/.virtualenvs/myproj-django1.7/local/lib/python2.7/site-packages/django/apps/registry.py", line 89, in populate
    "duplicates: %s" % app_config.label)
django.core.exceptions.ImproperlyConfigured: Application labels aren't unique, duplicates: foo

What's the problem and how do I resolve it?

Answer 1

The problem is that with the changes to apps in Django 1.7, apps are required to have a unique label.

By default the app label is the package name, so if you've got a package with the same name as one of your app modules (foo in this case), you'll hit this error.

The solution is to override the default label for your app, and force this config to be loaded by adding it to __init__.py.

# foo/apps.py

from django.apps import AppConfig

class FooConfig(AppConfig):
    name = 'full.python.path.to.your.app.foo'
    label = 'my.foo'  # <-- this is the important line - change it to anything other than the default, which is the module name ('foo' in this case)

and

# foo/__init__.py

default_app_config = 'full.python.path.to.your.app.foo.apps.FooConfig'

See https://docs.djangoproject.com/en/1.7/ref/applications/#for-application-authors

Answer 2

I found simple solution for this. In my case following line is added twice under INSTALLED_APPS,

'django.contrib.foo',

Removed one line fixes the issue for me.

Answer 3

I had the same error - try this:

in INSTALLED_APPS, if you are including 'foo.apps.FooConfig', then Django already knows to include the foo app in the application, there is therefore no need to also include 'foo'. Having both 'foo' and 'foo.apps.FooConfig' under INSTALLED_APPS could be the source of your problem.

Answer 4

As therefromhere said this is a new Django 1.7 feature which adds a kind of “app registry” where applications must be determined uniquely (and not only having different python pathes).

The name attribute is the python path (unique), but the label also should be unique. For example if you have an app named 'admin', then you have to define the name (name='python.path') and a label which must be also unique (label='my admin' or as said put the full python path which is always unique).

Answer 5

Well, i created auth app, and i've included it in INSTALLED_APP like src.auth (because it's in src folder) and i got this error, because there is django.contrib.auth app also. So i renamed it like authentication and problem solved.

Answer 6

I got the same problem. Here my app name was chat and in the settings.py , under installed apps i have written chat.apps.ChatConfig while i have already included the app name chat at the bottom. When i removed the chat.apps.ChatConfig mine problem was solved while migrations. This error may be due to the same instance that you might have defined you app name foo twice in the settings.py. I hope this works out!!

Answer 7

If you want to back older version, command

pip install django==1.6.7