[feature] Use docker images as rootfs

[antoinemartin]

The documentation already contains a small howto on how to create root fses from docker images (here).

The idea would be to include this directly in Wsl-Manager. There would be benefits:

• Use of public registries (docker hub, github) to store root filesystems.
• Ability to 'extend' a root filesystem the same way a new docker image extends an existing one.
• Use the containers storage as the storage for the root filesystems.
• docker performs downloads and checks.

Possible scenario (TBD)

The simplest scenario would be the following:

• Have a minimal distribution including:
  • docker
  • docker buildx
    or
  • BuildKit
  • buildctl

Wsl-Manager would use this distribution to:

• Pull root fs images
• Extract rootfs from images
• Build other root images

The docker version is easier to use because it already bundles buildkit (via an image download?) and containerd. The buildkit version includes containerd.

The tar export from a docker container can be piped directory into wsl --import from WSL:

> docker create --name toexport alpine:latest
> docker export toexport |  wsl.exe --import te $(wslpath -w $(pwd)) -

References

• How to create a docker image from a root fs
• Skopeo does not work on windows. However, there is a recipe to build it and a fork provide some builds. Have in mind that skopeo doesn't solve the image to rootfs issue.