Django + Heroku deployment - django

Question

I tried several times now to deploy my Heroku application but I always receive the attached error message. After adding DISABLE_COLLECTSTATIC=1 it works and I can remove it after. But it never works when it's enabled which it should be. Here a picture of my folder structure if it's needed https://drive.google.com/file/d/11L8jpFzYfDYT3Ob4G-soaGhL0pgU24iZ/view?usp=sharing
! Warning: Multiple default buildpacks reported the ability to handle this app. The first buildpack in the list below will be used.
Detected buildpacks: Python,Node.js
See https://devcenter.heroku.com/articles/buildpacks#buildpack-detect-order
-----> Python app detected
-----> Installing python-3.6.6
-----> Installing pip
-----> Installing dependencies with Pipenv 2018.5.18…
Installing dependencies from Pipfile.lock (d438cb)…
-----> Installing SQLite3
-----> $ python manage.py collectstatic --noinput
Traceback (most recent call last):
File "manage.py", line 15, in <module>
execute_from_command_line(sys.argv)
File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
utility.execute()
File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 347, in execute
django.setup()
File "/app/.heroku/python/lib/python3.6/site-packages/django/__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "/app/.heroku/python/lib/python3.6/site-packages/django/apps/registry.py", line 112, in populate
app_config.import_models()
File "/app/.heroku/python/lib/python3.6/site-packages/django/apps/config.py", line 198, in import_models
self.models_module = import_module(models_module_name)
File "/app/.heroku/python/lib/python3.6/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 994, in _gcd_import
File "<frozen importlib._bootstrap>", line 971, in _find_and_load
File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 678, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/app/.heroku/python/lib/python3.6/site-packages/django/contrib/auth/models.py", line 2, in <module>
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
File "/app/.heroku/python/lib/python3.6/site-packages/django/contrib/auth/base_user.py", line 47, in <module>
class AbstractBaseUser(models.Model):
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/base.py", line 114, in __new__
new_class.add_to_class('_meta', Options(meta, app_label))
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/base.py", line 315, in add_to_class
value.contribute_to_class(cls, name)
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/models/options.py", line 205, in contribute_to_class
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/__init__.py", line 33, in __getattr__
return getattr(connections[DEFAULT_DB_ALIAS], item)
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/utils.py", line 199, in __getitem__
self.ensure_defaults(alias)
File "/app/.heroku/python/lib/python3.6/site-packages/django/db/utils.py", line 171, in ensure_defaults
conn.setdefault('ATOMIC_REQUESTS', False)
AttributeError: 'NoneType' object has no attribute 'setdefault'
! Error while running '$ python manage.py collectstatic --noinput'.
See traceback above for details.
You may need to update application code to resolve this error.
Or, you can disable collectstatic for this application:
$ heroku config:set DISABLE_COLLECTSTATIC=1
https://devcenter.heroku.com/articles/django-assets
! Push rejected, failed to compile Python app.
! Push failed

Answer 1

It might be unrelated to collectstatic. Similar exception was described here: python error AttributeError: 'str' object has no attribute 'setdefault'.
I'd suggest checking your DATABASES setting in your settings.py. Check out django-heroku (https://github.com/heroku/django-heroku) if you're not using it already and just use this in your settings:
import django_heroku
django_heroku.settings(locals())