Current situation

I want to be able to package flatcar-install and a specific version of the image (e.g. https://stable.release.flatcar-linux.net/amd64-usr/current/flatcar_production_image.bin.bz2) in a docker container so it can be easily installed by a tinkerbell workflow action in a air-gap environment.

Impact

flatcar-master/bin/flatcar-install need to be changed in a backwards compatible way.

Ideal future situation

add a switch to flatcar-install that only downloads the image and exits. for example with:

flatcar-install -D image.bz2

Or do not even have an argument, just download the file to the current directory, e.g.:

flatcar-install -D

And a script of mine can look for the actual filename and later pass it to flatcar-install -f.

Then later I can install it with:

flatcar-install -f image.gz2 -d /dev/sda

Having this flag is easier than implementing the whole download/verification logic myself; I can just use something like ADD https://github.com/flatcar-linux/init/blob/build-1688.4.0/bin/flatcar-install in my Dockerfile. What do you think?