The Wonderful Apps aren't loaded yet Error - django

Question

I've searched SO and Google and can't find an answer to my problem.
I've launched my virtualenv and ran this command in the terminal:
python bin/process_messages.py
and this error occurs:
Stacktrace:
Traceback (most recent call last):
File "bin/process_messages.py", line 6, in <module>
from xyz.models import get_sku
File "/Users/myname/.environments/xyz_env/lib/python3.6/site-packages/xyz/models.py", line 19, in <module>
class Suppliers(models.Model):
File "/Users/myname/.environments/xyz_env/lib/python3.6/site-packages/django/db/models/base.py", line 110, in __new__
app_config = apps.get_containing_app_config(module)
File "/Users/myname/.environments/xyz_env/lib/python3.6/site-packages/django/apps/registry.py", line 247, in get_containing_app_config
self.check_apps_ready()
File "/Users/myname/.environments/xyz_env/lib/python3.6/site-packages/django/apps/registry.py", line 125, in check_apps_ready
raise AppRegistryNotReady("Apps aren't loaded yet.")
django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
I thought it wasn't running django.setup so I added that to the script. Here is my code:
#!/usr/bin/env python
import os
import django
import boto3
from xyz.settings import SQS_QUEUE_NAME
from xyz.models import get_sku
__author__ = 'me'
def check_django_environment(default_settings):
# Environment setup for Django project files:
os.sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
if not os.environ.get('DJANGO_SETTINGS_MODULE'):
# Don't override settings if it is specified.
os.environ['DJANGO_SETTINGS_MODULE'] = default_settings
from django.conf import settings
return getattr(settings, 'DEBUG', None)
check_django_environment('xyz.settings')
django.setup()
# Get the service resource
sqs = boto3.resource('sqs')
# Get the queue
queue = sqs.get_queue_by_name(QueueName=SQS_QUEUE_NAME)
for message in queue.receive_messages():
print(message)
if message.message_attributes is not None:
print(message.message_attributes)
#sku = message.message_attributes
db_sku = get_sku(sku)
print(db_sku)
break
My Installed apps:
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'xyz',
]

Answer 1

By importing get_sku, you are importing your models before django.setup() has run. You need to move this import down so it happens after django.setup().
In a stand-alone script that uses Django, I generally have two groups of imports. The first contains the bare minimum to get Django setup, the second contains all the other imports, including models etc.:
#!/usr/bin/env python
import os
import django
__author__ = 'me'
def check_django_environment(default_settings):
# Environment setup for Django project files:
os.sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
if not os.environ.get('DJANGO_SETTINGS_MODULE'):
# Don't override settings if it is specified.
os.environ['DJANGO_SETTINGS_MODULE'] = default_settings
from django.conf import settings
return getattr(settings, 'DEBUG', None)
check_django_environment('xyz.settings')
django.setup()
import boto3
from xyz.settings import SQS_QUEUE_NAME
from xyz.models import get_sku

Answer 2

In addition to knbk's answer, you can also just use manage.py.
Here's an example script, let's say script.py:
from xyz.models import get_sku
if __name__ == '__main__':
print(get_sku)
And you run it like:
./manage.py shell < script.py
Maybe not what you're looking for, but worth knowing, nonetheless.