Conf loader

Python Web Extras is unique in it's simplicity of loading dynamic settings, one of the biggest hurdles of setting up enviroments and configurations of any project that consumes a lot of time.

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Table of Contents

• Conf loader
  • Table of Contents
  • Automated load conf settings
    • Django settings module
      • Dynamically loading
    • Python Web Extras module
    • Dynamically loading
    • Example
      • Dynamically loading
  • Full working cookiecutter

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Automated load conf settings

This package also provides a clean way to load your setting in a very django similar fashion.

Example:

# views.py

python_web_extras.fastapi.conf import settings

Although this is very simple, there is a lot going on here. Since these package was based on the simplicity of loading modules (coming from django) we decided to have a similar approach. Let's see:

Django settings module

Django by default has a DJANGO_SETTINGS_MODULE where the default is always the name of the project.settings generated, example myapp.settings.

Dynamically loading

Django allows to call the manage.py with different settings with two ways.

• Environment variable:

DJANGO_SETTINGS_MODULE='myapp.development.settings' python manage.py runserver

• Settings property:

python manage.py runserver --settings='myapp.development.settings'

Python Web Extras module

The approach is basically the same as django but we called it FASTAPI_SETTINGS_MODULE and it works exactly the same way when it comes to loading the settings module.

Dynamically loading

We prefer the loading of settings via environment variables as we believe it's cleaner.

Example:

# main.py

# Load the settings from the module
from fastapi import FastAPI

python_web_extras.fastapi.conf import settings

# the rest of the logic for the app
app = FastAPI(**settings.fastapi_kwargs)

FASTAPI_SETTINGS_MODULE='core.development.settings' python app.py

The above example is expecting the module location to be passed as a string into FASTAPI_SETTINGS_MODULE or else it will default to python_web_extras.fastapi.api_settings.

Example

An application structure, quite complex and similar to a production ready version.

└── src
    ├── __init__.py
    ├── apps
    │   ├── __init__.py
    │   └── accounts
    │       ├── __init__.py
    │       ├── models.py
    │       └── v1
    │           ├── __init__.py
    │           ├── routes.py
    │           └── views.py
    ├── core
    │   ├── __init__.py
    │   ├── configs
    │   │   ├── __init__.py
    │   │   ├── databases
    │   │   │   ├── __init__.py
    │   │   │   ├── config.py
    │   │   │   ├── routers.py
    │   │   │   └── settings.py
    │   │   ├── development
    │   │   │   ├── __init__.py
    │   │   │   ├── local_settings.py
    │   │   │   └── settings.py
    │   │   ├── settings.py
    │   │   ├── testing
    │   │   │   ├── __init__.py
    │   │   │   └── settings.py
    │   │   └── urls.py
    └── main.py

The application is split by responsabilities and all the settings live inside a core/configs module.

1. core.configs.settings - App settings.
2. core.configs.development.settings - Development settings.
3. core.configs.testing.settings - Testing settings.

Development and testing are inherited from the main settings and therefore there is no reason to replicate existing configurations and keep the codebase clean.

Dynamically loading

Using the example above we want to start the environments with the correct settings.

• main.py file

  # main.py
  
  # Load the settings from the module
  from fastapi import FastAPI
  python_web_extras.fastapi.conf import settings
  
  # the rest of the logic for the app
  app = FastAPI(**settings.fastapi_kwargs)
  

• Start different environtments.

  FASTAPI_SETTINGS_MODULE='core.configs.development.settings' src.main # Starts the dev settings
  FASTAPI_SETTINGS_MODULE='core.configs.testing.settings' src.main # Starts the testing settings
  FASTAPI_SETTINGS_MODULE='core.configs.settings' src.main # Starts with main settings
  

python_web_extras.fastapi.conf import settings will know which settings to load by reading the enviroment variable FASTAPI_SETTINGS_MODULE keeping the code clean and the configurations separated.

Full working cookiecutter

This package is being already used with a similar approach here. A cookiecutter already prepared and designed for business.