support overriding "packages" from included manifests

[jamescassell]

Feature Request

Sometimes, one wants to base a cosa build on an existing manifest, but wants to skip one or two packages in the base manifest for various reasons (such as not available in the repo, or undesired package.)

Desired Feature

Ability to use something like exclude-packages to exclude packages that have been explicitly included in the include'ed manifest(s).

Example Usage

exclude-packages:
  - btrfs-progs

Other Information

btrfs-progs is not available on CentOS, and I'd like to base my CentOS cosa builds on the Fedora CoreOS configs, which include that package. (as one example)

[cgwalters]

This is more of an rpm-ostree RFE, and in fact we recently implemented an exclude-packages but for something different.

What I'd recommend at the moment is to fork https://github.com/coreos/fedora-coreos-config/blob/testing-devel/manifests/fedora-coreos-base.yaml and inherit from https://github.com/coreos/fedora-coreos-config/blob/testing-devel/manifests/ignition-and-ostree.yaml

That's what RHCOS does.

See also this PR.

[cgwalters]

The rpm-ostree RFE would probably be more like:

packages-recommended:
  - btrfs-progs

or so? Conceptually the manifest + postprocess + overlays is much like an RPM package; packages: key is like Requires:, so this would be adding the equivalent of Recommends:.

But still, we have larger issues around making fedora-coreos-base.yaml be something supportable for other things to inherit.

See also the whole series of PRs like:

• https://github.com/coreos/fedora-coreos-config/pull/132
• https://github.com/coreos/fedora-coreos-config/pull/165
• https://github.com/coreos/fedora-coreos-config/pull/168

etc. that were created when trying to have RHCOS inherit from the FCOS config.