Add ubuntu example image

[shawn111]

This is an example of ubuntu image referred to arch example.

[allisonkarlitskaya]

I think the cfsctl command copied to /usr/bin is going to be broken because there's no mkcomposefs available on Ubuntu. In particular, pulling a new image and preparing it for booting probably won't work.

Can you please look into that? In all of the other examples, we can "install updates", but with mkcomposefs unavailable I'm afraid it won't work for this one.

[cgwalters]

You should always give -L to curl to handle redirects and --fail to handle HTTP level errors instead of giving HTML back.

Use --remote-name-all to download mutiple files at once too.

So combined:

RUN curl -Lf --remote-name-all https://kernel.ubuntu.com/mainline/v6.12/amd64/linux-headers-6.12.0-061200-generic_6.12.0-061200.202411220723_amd64.deb \
    https://kernel.ubuntu.com/mainline/v6.12/amd64/linux-headers-6.12.0-061200_6.12.0-061200.202411220723_all.deb \
    https://kernel.ubuntu.com/mainline/v6.12/amd64/linux-image-unsigned-6.12.0-061200-generic_6.12.0-061200.202411220723_amd64.deb \
    https://kernel.ubuntu.com/mainline/v6.12/amd64/linux-modules-6.12.0-061200-generic_6.12.0-061200.202411220723_amd64.deb

It'll also avoid creating 4 separate TCP connections.

(Or of course, add a separate apt repo with these packages)

[allisonkarlitskaya]

I just merged this: 60ff784#diff-8906835152921ef903f55779586f3a092362f65fca98df94d71801cf974ec95bR42 as a super janky way of getting composefs working on Ubuntu, for the GitHub actions runners, so we can CI the examples.

It might be useful to do something less awful. Ideas:

• a composefs PPA or something would be awesome... I might look into that today.
• implement erofs writing in composefs-rs to lose our mkcomposefs dependency
• ???

[allisonkarlitskaya]

For the record, the thing that should be possible is that you push your created container image to a registry somewhere, and then inside of the booted system image you can say something like:

cfsctl oci pull docker://quay.io/your/image
cfsctl oci prepare-boot [image id]

and then reboot and see the second image in the systemd-boot menu. It should even work to have separate OS installs (I tested this between the Fedora and Arch images, for example).

[shawn111]

I just merged this: 60ff784#diff-8906835152921ef903f55779586f3a092362f65fca98df94d71801cf974ec95bR42 as a super janky way of getting composefs working on Ubuntu, for the GitHub actions runners, so we can CI the examples.

It might be useful to do something less awful. Ideas:

• a composefs PPA or something would be awesome... I might look into that today.
• implement erofs writing in composefs-rs to lose our mkcomposefs dependency
• ???

It is so nice that we have CI to test the example builds.

It been a long time ago, I didn't login launchpad.
I need to find my account out.

[shawn111]

For the record, the thing that should be possible is that you push your created container image to a registry somewhere, and then inside of the booted system image you can say something like:

cfsctl oci pull docker://quay.io/your/image
cfsctl oci prepare-boot [image id]

and then reboot and see the second image in the systemd-boot menu. It should even work to have separate OS installs (I tested this between the Fedora and Arch images, for example).

Thanks, I pushed to docker.io/shawn111/cfs-images:ubuntu.

./cfsctl --repo tmp/sysroot/composefs/ oci pull docker://docker.io/shawn111/cfs-image:ubuntu
Error: Opening image

Caused by:
    failed to invoke method OpenImage: failed to invoke method OpenImage: reading manifest ubuntu in docker.io/shawn111/cfs-image: manifest unknown