Intentionally removing volumes in override docker-compose files

Question

For production deployment, I don't want shared volumes. So, I have an override file but this does not remove the volumes.

Is there a way to remove shared volumes in an override file? I'd like to avoid having an override just for development, because that seems clunky to use.

This is my docker-compose.yml:

version: '2' # other services defined here services:   web:     build:       context: .     # other configuration     volumes:       - .:${APP_DIR} 

And my docker-compose.prod.yml:

version: '2' services:   web:     volumes: []     restart: always 

Answer 1

I'm assuming you want to use docker-compose up to start the development version, and have a second config file to extend it for production.

If you want to make sure to override volumes completely, use a third config file, docker-compose.override.yml. Put all your volume definitions for development in there.

docker-compose up extends the base config with this file by default. But when you do something like docker-compose -f docker-compose.yml -f production.yml, the docker-compose.override.yml file won't be loaded, and you'll get only the volumes from the production file.

Answer 2

When merging a list entry in docker-compose, it adds new maps but doesn't remove existing volume mappings.

You can implement this by either making dev have the override file, or up to version 2.1 you can extend a common docker file rather than applying overrides which lets to devs point to a single file.

This could be your docker-compose.yml:

version: '2' # other services defined here services:   web:     extends:       file: docker-compose.prod.yml       service: web     build:       context: .     restart: no     volumes:       - .:${APP_DIR} 

And your docker-compose.prod.yml would contain all the common configuration and prod settings:

version: '2' services:   web:     # other configuration     restart: always