Rails + Docker project to learn how to use these tools
Following the semaphoreci.com tutorial.
Watch the Get started with Docker video walkthrough from DockerCon 2020.
Use Dockerfile config from Docker Docs
$ docker build -t rails-toolbox .
-t flag to point to specify a repository and tag at which to save the new image if the build succeeds.
$ docker-compose run --no-deps web rails new . --force --database=postgresql
Since this changes the Gemfile, the image needs to be built again.
$ docker-compose build
$ docker-compose up