How to Docker on Rails?

One of the most interesting thing in starting a new project is the possibility to learn new things. For the last year, I had the occasion to work on the ops side of running an app and not just limit myself to the backend programming. It was the occasion to learn more about docker and also aws services and kubernetes. Now I want to share a bit of what I would have wanted to know as a series of articles. The first one will be about running a rails app in docker.