Django model outside of django

Question

I have a non django project for which i would like to use the django models for data access layer.

Added the models lib in requirements.txt
django-model-utils==3.1.1

And code set it up like below:

from django.conf import settings
from django.db import models

settings.configure(
  DATABASE_ENGINE='django.db.backends.mysql',
  DATABASE_NAME='***',
  DATABASE_USER='***',
  DATABASE_PASSWORD='***',
  DATABASE_HOST='***',
  DATABASE_PORT='***')

class Bus(models.Model):
  class Meta:
    db_table = 'my_custom_bus'

  bus_name = models.CharField(max_length=20)
  bus_description = models.CharField(max_length=100)

But when i ran the above code, i am getting the following error: django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.

In order to fix the above error, i ran:

import django  
django.setup()

Now when i try, i get:
Bus doesn't declare an explicit app_label and isn't in an application in INSTALLED_APPS

Am i missing some setting here or is there any light weight model only lib in python?

You should create the entire app structure for django. Create an app, define your models there, then import from the app. — sytech, Feb 27 '18 at 18:58
try https://stackoverflow.com/questions/2180415/using-django-database-layer-outside-of-django — yoyoyoyo123, Feb 27 '18 at 18:59
Thanks! That seems a bit heavy weight, mine is a `pants` project. Is there a light weight models library that i can use to interact with database? — Pratik Khadloya, Feb 27 '18 at 19:02
I strongly recommend not to use a monolithic library like Django if the only thing you need is the ORM. You will be in a world of pain, fighting Django's opinions all the way. There are better choices out there, [sqlalchemy](https://github.com/zzzeek/sqlalchemy) for example has a far superior ORM which will be more "pluggable". — wim, Feb 27 '18 at 19:10
@wim I disagree, and basically use Django for anything that involves a relational database setup. Though I do keep a standard project structure. Once you have done it a few times, it not many steps. And the benefit of having the admin available for populating and viewing data during development is a huge advantage. SQL Alchemy would be the obvious ORM replacement, but that has a way steeper learning curve than Django's. — wobbily_col, Feb 27 '18 at 20:30
In my particular case, wherein its simply a set of scripts downloading data from apis and saving in database, sqlalchemy is suiting well. — Pratik Khadloya, Feb 28 '18 at 18:47

score 1 · Answer 1 · answered Dec 20 '18 at 06:58

(It's an old question, but i answer it, maybe help others.)

option 1 (recommended)

seeing comments, you mentions:

In my particular case, wherein its simply a set of scripts downloading data from apis and saving in database, sqlalchemy is suiting well.

In some situations (like what you mentioned) you can use django management commands. For example if you want to do some tasks that are related to django models and should run in background. like some crontab jobs like updating database fields every 5 minutes or executing some script related to some apis that should run and update database models.

For this, create a management command like below and your good to go:

in your app, create a folder management. then add an empty __init__.py file to it. next create another folder called commands in that folder and yet add another empty __init__.py to commands folder. now create your script files in commands folder. for example test_script.py.

Now add this in test_script.py:

from django.core.management.base import BaseCommand

class Command(BaseCommand):

    def handle(self, *args, **kwargs):
        # Add your script codes here.

Now to run it, simply execute this command: python manage.py test_command
for more details read this link

option 2

There is a powerful ORM for python sqlalchemy. You can use it if you don't want to use any part of django or create another django and add your non-django project's code to it. But remember you need to define your django model design with sqlalchemy too. But it's not that hard to do that.

option 3

as my friends suggested in comments, you can config another project to use your existing django project as an app. follow Using Django database layer outside of Django?

Django model outside of django

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