RFC: add support for building NemOS images to livecd-rootfs

[Isaac True]

I discussed a while ago with the Launchpad team about potentially adding support for Kiwi to livecd-rootfs, and thus eventually adding it to Launchpad in the future. I've now looked more closely into this and I've put together a merge proposal [1] with my changes and I'd love to get some feedback.

The idea is to use a checked repository [2] or a package like the one that is build from that repository and available in a PPA [3] as the image configuration. This repository/contains the Kiwi "appliance description", which instructs the Kiwi build tool on how to build the system.

For reference, the upstream Kiwi repository is here [4] and the docs here [5].

I've tested the workflow with the nemos-image .deb package from the PPA and the following commands:

$ ARCH=amd64 SUITE=lunar PROJECT=kiwi SUBPROJECT=nemos/nemos-images-reference-lunar live-build/auto/config
$ ARCH=amd64 SUITE=lunar PROJECT=kiwi SUBPROJECT=nemos/nemos-images-reference-lunar live-build/auto/build

The SUBPROJECT refers to a Kiwi description in /usr/share/kiwi/, but can be overriden to be an arbitrary path by setting the KIWI_DESCRIPTION variable.

[1] https://code.launchpad.net/~itrue/livecd-rootfs/+git/livecd-rootfs/+merge/439825
[2] https://git.launchpad.net/~nemos-team/nemos/+git/nemos-images/tree/
[3] https://launchpad.net/~nemos-team/+archive/ubuntu/ppa
[4] https://github.com/OSInside/kiwi
[5] https://osinside.github.io/kiwi/overview.html

[Isaac True (itrue)]

I have rearchitected the patchset to be more NemOS-specific, rather than allowing any arbitrary Kiwi image to be built.

Now, instead of passing a path to an image description in the SUBPROJECT, it should be one of the predefined values which denote which kind of image should be built. Furthermore, PROJECT should now be set to nemos rather than kiwi.

SUBARCH support has also been added to support different kinds of hardware platforms.

E.g. for a generic amd64 reference image with all features enabled:

env ARCH=amd64 SUITE=lunar PROJECT=nemos SUBPROJECT=reference live-build/auto/config

or for a minimal arm64 image for the NXP S32G2 platform

env ARCH=arm64 SUBARCH=nxp-s32g2 SUITE=lunar PROJECT=nemos SUBPROJECT=minimal live-build/auto/config

or for a generic arm64 reference image with all features enabled and extra development tools:

env ARCH=arm64 SUITE=lunar PROJECT=nemos SUBPROJECT=reference-development live-build/auto/config

[Loïc Minier (lool)]

livecd-rootfs changes +1 to go be merged and uploaded, would just like to understand why running lsb_release is needed to set SUITE= when it should come from Launchpad – so weird

[John Chittum (jchittum)]

What is NemOS? I'm a little lost on understanding the need for the support in livecd-rootfs generally. If i'mi reading this, and the MPs correctly, it's related to devices supporting a specific customer, and having the ability to build the OS for them?

this is the first I've seen of NemOS. Since we're working on build tools other than livecd-rootfs for future releases, it'll be helpful for me to understand the general context (if it's proprietary info, feel free to send it to me on an internal Canonical platform).

[Isaac True (itrue)]

@lool has already answered offline, but for posterity and for anyone else who is looking at the bug: NemOS is the public project name for the reference integrations we are doing for a customer. It is an Ubuntu derivative built from packages in the Ubuntu archives, not a flavour. They've mandated the use of Kiwi in this project, and aren't open to using other build tools (like ubuntu-image).