Docker deployment

[Kobzol]

We would like to have the option to deploy Kelvin fully inside Docker, ideally with a single command, if possible. We want to have the following services running inside Docker, networked together:

• The Django backend
• nginx, which will serve the Django backend
• Postgres (DB)
• Redis (cache)
• A set of Django RQ workers

This corresponds to the architecture described in docs.

Ideally, it should be possible to deploy everything with a single docker-compose.yml file. All configuration (directory/file paths, ports etc.) should ideally be configurable in the docker-compose file, through environment variables loaded from an .env file. You can find an example of that in the existing docker-compose.yml file.

Here is a broad TODO list of things (in almost arbitrary order) that we need to do in order to make this possible:

• [ ] Add nginx to docker-compose.yml
  • [ ] Make it possible to map a host directory that contains nginx config
  • [ ] Make it possible to map a host directory that contains certificates
• [ ] Make it possible to map a host directory containing persistent data for the Redis instance
• [ ] Make sure that all the services in the docker compose file can talk to each other through the network
• [ ] Build the JS frontend in the Kelvin Dockerfile, to make it available in the Docker image
  • [ ] Use a multi-stage build to only include the frontend.js, frontend.css files and the dolos directory in the final Docker image
• [ ] Make it possible to map a host directory containing local_settings.py, which will be used to override configuration for the Django backend running inside of Docker
• [ ] Setup nginx so that it serves the Kelvin Django backend
• [ ] Configure a startup script that will run python3 manage.py migrate everytime the whole Docker deployment starts
• [ ] Make it possible to start RQ workers inside Docker
  • [ ] Make it possible to run each worker in multiple instances
  • [ ] Workers use Docker internally, configure Docker-in-Docker. An example can be found here, but it needs to be tested if it works, and how it interacts with Docker permissions.

If there is a better way to do this, other than docker-compose, we can also try it. But please no Kubernetes :)

[JersyJ]

As mentioned on VSB Discord, I am taking this task. (just noticing -> no one works on this in paralell).