# First time setup:
docker-compose build    # Builds your custom image from Dockerfile
docker-compose up -d    # Starts containers using your custom image

# If you change the Dockerfile later:
docker-compose build    # Rebuild the image
docker-compose up -d    # Recreate containers with new image

# Or do both at once:
docker-compose up -d --build

• copy files to docker container: docker cp foo.txt container_id:/foo.txt
• copy files from docker container: docker cp container_id:/foot.txt foo.txt
• prune unneeded files (save disk space): sudo docker system prune -a -f

• docker system df: show overall space usage by category
• docker inspect $(docker ps -q) | grep -A 10 Mounts: see what volume goes with what container
• docker inspect CONTAINER_NAME --format '{{range .Mounts}}{{.Name}} -> {{.Destination}}{{println}}{{end}}' : list what volume is associated with the container
• docker ps: list docker containers

• When removing a service use docker compose down -v instead of docker compose down.
  • The -v removes the associated volumes at the same time.
• When updating images, after pulling and restarting, run docker image prune to remove the dangling images

• Watchtower is a container which auto updates Docker containers
• It will only update containers with updates that have the same tag
  • to always get the latest version use the tag latest
  • you can check which images have which tags with docker images
    • some images might have latest but not be base images so they won't be updated
• check the logs: docker logs watchtower
• if you want Watchtower to skip trying to update an image add to docker-compose.yml

 services:
  db:
    # label the image as each image gets its own label
    image: mariadb:latest # an example
    labels:
      - "com.centurylinklabs.watchtower.enable=false" # ADD THIS LINE