Enchancement: Automatically cleanup unused docker images

[Hedius]

Discussion on discord: https://discord.com/channels/884667213326463016/981983949402292274

It seems like casaOS does not delete unused docker images?

At least a user had the problem that his disk was full.

docker image prune was able to free up 5GB of unused docker images.

Idea: maybe automatically remove unused docker images?

A cronjob once per night for example would be a quick and dirty fix for that: docker image prune --all

[Protektor-Desura]

If you use something like watchtower to update your dockers then you can have it automatically remove old unused images.

services:
  watchtower:
    command: --cleanup --rolling-restart --include-stopped
    container_name: watchtower
    environment:
      - TZ=America/Chicago
    hostname: watchtower
    image: containrrr/watchtower:latest
    networks:
      - archon
    restart: unless-stopped
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock:rw"


networks:
  archon:
    external: true```

[Hedius]

That wasn't my point.

My point is that by default casaos does not delete images and it should do that. Without a 3rd party service in the background.

Especially because people on the discord suddenly have full disks without knowing why.

[Protektor-Desura]

Containers and images should never contain any configuration. If you want to preserve the configuration people should just use volumes. Promoting anything else is totally wrong.

No you don't save your configuration and settings for the server/app in a volume. You should be saving them in a mounted directory to easier back them up and edit the files easier if needed.

[Protektor-Desura]

There are three parts to the docker, the config directory, the image and then running docker part. If you are using yml files then there is that part as well.

[Hedius]

Docker compose has nothing to do with this topic.... and please don't try to explain containers to me.

[Protektor-Desura]

Then don't say you don't get my argument and then get nasty when I explain my reasoning.

[gjchester]

If a user deletes an app, then a user expects that the app is fully deleted. And not that the disk gets full slowly /var/lib/docker without them knowing why.
You cannot expect from users to understand how containers work. (See the discord).

I can totally understand what you mean, but while new users may expect docker containers to be removed after the app is deleted, thats not expected Docker behaviour and experienced docker users may be confused by such actions.

Maybe the solution lies in the App Delete function of CasaOS runs a docker purge as part of its process?

[AuthorShin]

As I said here just add a button to switch between advanced and basic mode and then add options like "Automatically clean up unused docker images" under basic or advanced mode so users can choose from.
What casaOS needs, is to give the users more choice power.