Extract the Filesystem of a Container Image
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Internally, container images have a layered structure,
with each layer representing a filesystem diff produced by a corresponding RUN, COPY, or ADD instruction in its Dockerfile.
However, when a container is created from an image,
its filesystem appears as a standard Linux directory structure.
Usually, it's a responsibility of the runtime to mount the image layers as a container filesystem,
but sometimes, a need to manually extract the packaged filesystem into a local folder may arise.
In particular, this may be useful for debugging purposes.
In this challenge, you will need to unpack the filesystem of a container image into a local directory.
The image is already pulled for you -
you can find it in the output of the docker images command.
Store its filesystem in the ~/imagefs directory.
Make sure you export the filesystem of this exact image variant (platform linux/s390x),
because it may differ from the filesystem of the same image on other platforms.
Hint 1
Don't use the docker save command - it dumps the "raw" layered structure of the image,
while you need to extract the "baked" filesystem of the image.
Hint 2
The crane export command also writes the merged filesystem of an image as a tar stream.
Keep in mind that crane pulls the image from the registry by itself
and exports the linux/amd64 variant unless you pass the --platform flag.
Hint 3
Feeling a bit lost? Check out this short tutorial - How To Extract Container Image Filesystem Using Docker.