An example on how to leverage Docker for Ruby (on Rails) development.
docker-compose build --pull
docker-compose up app
docker-compose ps will tell you, on which local port the application binds.
docker-compose build --pull
docker-compose -f docker-compose.test.yml run --rm app
docker-compose pull
Have you tried to turn it off an on again?
# Turn off
docker-compose kill
docker-compose rm -fv
# Turn on
docker-compose up app
Check the logs:
docker-compose logs
You can enter a running container:
docker-compose exec app /bin/sh