python-application-operator

This is proof of concept

Description

This project is using Canonical Operator Framework

The main idea is to simplify python application deployment by using Gunicorn to serve it to the internet

Requirements

• Install and bootstreap k8s with juju (https://juju.is/docs/kubernetes)
• Install charmcraft with sudo snap install charmcraft.

Usage

1. Build charm charmcraft build
2. Deploy charm juju deploy ./python-application-operator.charm --config examples/config_site1.yaml

Configuration

• Python: Charm can use any official python image based on ubuntu which can be defied as image parameter
• Repostiory: Currently only publicly available (or without authorization) repositores are supported
• Entrypoint: Application shoul be prepared to work with WSGI servers and application entrypoint shold be provided.
  • Django example: https://docs.djangoproject.com/en/3.1/howto/deployment/wsgi/gunicorn/
  • Flask Example: https://www.digitalocean.com/community/tutorials/how-to-serve-flask-applications-with-gunicorn-and-nginx-on-ubuntu-18-04

Configuration

Read config.yaml

Examples

Sample application that are were tested:

• https://github.com/kirek007/python-hello-web

  To deploy use juju deploy ./python-application-operator.charm --config examples/config_flask.yaml

• https://github.com/django-ve/django-helloworld

  To deploy use juju deploy ./python-application-operator.charm --config examples/config_django.yaml

Developing

Create and activate a virtualenv with the development requirements:

virtualenv -p python3 venv
source venv/bin/activate
pip install -r requirements-dev.txt

Testing

Tests are not implemented but scaffolding is ready

The Python operator framework includes a very nice harness for testing operator behaviour without full deployment. Just run_tests:

./run_tests