config files for different development environments (Production, Dev, Testing)

Question

I am following a guide that specifies how to manage different configurations (DB_URI, LOGGER_NAME, etc...) per development environments.

I create a config module that is structured like this

\my_project\config\__init__.py

import os
import sys
from . import settings
# create settings object corresponding to specified env
APP_ENV = os.environ.get('APP_ENV', 'Dev')
_current_config = vars(setting).get(f'{APP_ENV}Config')
# copy attributes to the module for convenience
for atr in [f for f in dir(_current_config) if '__' not in f]:
 # environment can override anything
 val = os.environ.get(atr, getattr(_current_config, atr))
 setattr(sys.modules[__name__], atr, val)

\my_project\config\settings.py

class BaseConfig:
 DEBUG = True
 LOGGER_NAME = 'my_app'
class DevConfig(BaseConfig):
 # In actuality calling a function that fetches a secret 
 SQLALCHEMY_DATABASE_URI = 'sqlite://user.db'
class ProductionConfig(BaseConfig):
 DEBUG = False
 # In actuality calling a function that fetches a secret
 SQLALCHEMY_DATABASE_URI = 'sqlite://user.db'

calling the config

application.py

import config
config.SQLALCHEMY_DATABASE_URI 

This approach is kind of a hit and miss for me. on one hand it allows me to easily specify several environments (dev, stage, prod, dev) without having a complex if else logic in my settings.py.

On the other hand I dont like using setattr on sys.modules[__name__], seems a bit wonky to me. what do you think ?

Answer 1

Incase you are using Docker for deployment. The required environment variable can be configured as Kuberenetes configuration and it reads based on the deployment configuration environment.

• greybeard: Welcome to CodeReview@SE. Not all questions should be answered here, see How do I write a Good Answer?
• moshevi: thanks for the help, but my question is about python configuration. As I dont use docker at the moment