Runtime Error with Django-Tastypie: "App registry isn't ready yet."

[benjamin.e.white1@…]

Including django-tastypie as installed app prevents me from running server, migrating, etc. I'm on Python 3.3.3

Traceback pasted below. Goes away when I remove django-tastypie as installed app.

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/benjaminwhite/django-trunk/django/core/management/__init__.py", line 427, in execute_from_command_line
    utility.execute()
  File "/Users/benjaminwhite/django-trunk/django/core/management/__init__.py", line 391, in execute
    django.setup()
  File "/Users/benjaminwhite/django-trunk/django/__init__.py", line 21, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 105, in populate
    app_config.import_models(all_models)
  File "/Users/benjaminwhite/django-trunk/django/apps/base.py", line 180, in import_models
    self.models_module = import_module(models_module_name)
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/importlib/__init__.py", line 90, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1584, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1565, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1532, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 584, in _check_name_wrapper
  File "<frozen importlib._bootstrap>", line 1022, in load_module
  File "<frozen importlib._bootstrap>", line 1003, in load_module
  File "<frozen importlib._bootstrap>", line 560, in module_for_loader_wrapper
  File "<frozen importlib._bootstrap>", line 868, in _load_module
  File "<frozen importlib._bootstrap>", line 313, in _call_with_frames_removed
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/site-packages/tastypie/models.py", line 32, in <module>
    from tastypie.compat import AUTH_USER_MODEL
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/site-packages/tastypie/compat.py", line 14, in <module>
    User = get_user_model()
  File "/Users/benjaminwhite/django-trunk/django/contrib/auth/__init__.py", line 133, in get_user_model
    user_model = apps.get_model(app_label, model_name)
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 182, in get_model
    self.check_ready()
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 118, in check_ready
    raise RuntimeError("App registry isn't ready yet.")
RuntimeError: App registry isn't ready yet.
(HUMAN_WRITES)Benjamins-MacBook-Air:narrativize benjaminwhite$ python manage.py runserver
Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/benjaminwhite/django-trunk/django/core/management/__init__.py", line 427, in execute_from_command_line
    utility.execute()
  File "/Users/benjaminwhite/django-trunk/django/core/management/__init__.py", line 391, in execute
    django.setup()
  File "/Users/benjaminwhite/django-trunk/django/__init__.py", line 21, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 105, in populate
    app_config.import_models(all_models)
  File "/Users/benjaminwhite/django-trunk/django/apps/base.py", line 180, in import_models
    self.models_module = import_module(models_module_name)
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/importlib/__init__.py", line 90, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1584, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1565, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1532, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 584, in _check_name_wrapper
  File "<frozen importlib._bootstrap>", line 1022, in load_module
  File "<frozen importlib._bootstrap>", line 1003, in load_module
  File "<frozen importlib._bootstrap>", line 560, in module_for_loader_wrapper
  File "<frozen importlib._bootstrap>", line 868, in _load_module
  File "<frozen importlib._bootstrap>", line 313, in _call_with_frames_removed
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/site-packages/tastypie/models.py", line 32, in <module>
    from tastypie.compat import AUTH_USER_MODEL
  File "/Users/benjaminwhite/.virtualenvs/HUMAN_WRITES/lib/python3.3/site-packages/tastypie/compat.py", line 14, in <module>
    User = get_user_model()
  File "/Users/benjaminwhite/django-trunk/django/contrib/auth/__init__.py", line 133, in get_user_model
    user_model = apps.get_model(app_label, model_name)
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 182, in get_model
    self.check_ready()
  File "/Users/benjaminwhite/django-trunk/django/apps/registry.py", line 118, in check_ready
    raise RuntimeError("App registry isn't ready yet.")
RuntimeError: App registry isn't ready yet.

[loic84]

Out of curiosity, does 'tastypie' appear before 'django.contrib.auth' in settings.INSTALLED_APPS?

Edit: Actually, looking at the code that's irrelevant. get_user_model() depends on apps.get_model() which is not available until the app registry is ready.

One way to fix it in django-tastypie would be to have tastypie.compat.AUTH_USER_MODEL be a string (settings.AUTH_USER_MODEL) on Django 1.7 (or even Django 1.5+).

[Aymeric Augustin]

As implied here: ​https://docs.djangoproject.com/en/dev/topics/auth/customizing/#referencing-the-user-model the User module should be referenced by settings.AUTH_USER_MODEL at import time. get_user_model() doesn't work until the initialization sequence is complete.

We could clarify this section of the docs again, and also say something in the release notes. But the fix belongs to tastypie.

[Aymeric Augustin]

Related thread: ​https://groups.google.com/d/msg/django-developers/lmT1JxsWHPo/N2V9U5SN9gwJ

[Aymeric Augustin]

PR: ​https://github.com/django/django/pull/2416

[Aymeric Augustin <aymeric.augustin@…>]

In 1be31c320c2e0efa1730f73509d64e024ab31a0c:

Fixed #21875 -- Clarified that get_user_model() only works at run time.

Thanks Benjamin White for the report.