Comment 1 for bug 2037339

Reviewed: https://review.opendev.org/c/starlingx/root/+/896277
Committed: https://opendev.org/starlingx/root/commit/5fa60a542120d7dd510aabae237c18839127705e
Submitter: "Zuul (22348)"
Branch: f/antelope

commit 5fa60a542120d7dd510aabae237c18839127705e
Author: Luan Nunes Utimura <email address hidden>
Date: Fri Sep 22 13:18:37 2023 -0300

    Add sources.list for non-default layers

    After reestructuring `deb-local-binary` into multiple binary
    repositories, one for each layer, the image build now has access to
    three repositories by default:

      * deb-local-binary;
      * deb-local-binary-containers;
      * deb-local-build.

    Although these repositories are sufficient for the vast majority of
    images, there are some, such as `stx-openstackclients`, that require
    dependencies that are found in another repository:
    `deb-local-binary-openstack`.

    This image, as the name suggests, contains all the OpenStack clients
    currently supported by the StarlingX OpenStack application.

    As one can see in [1], although most clients are installed in the form
    of pip packages, i.e., through wheel files collected from the upstream
    indexes, there are two clients that are installed in the form of
    distribution packages:

      * python3-cinderclient;
      * python3-openstackclient.

    The reason why they are installed as distribution packages is because
    they have patches that are specific to StarlingX OpenStack -- [2] and
    [3] -- and also because the build procedure can easily identify them in
    `deb-local-build` and use the patched versions as expected by us (of
    course, it they have been built previously).

    The problem, however, is that although this image is currently being
    built, there is a detail in it that can cause problems at run time.

    Despite the build locating (and using) our patched packages, when it
    searches for their dependencies, it always ends up using binaries from
    repositories `deb-local-binary`, `deb-local-binary-containers` or
    `deb-local-build`.

    Which means that, if we have a dependency on
    `deb-local-binary-openstack` meant for OpenStack Antelope, and the same
    dependency on `deb-local-binary` meant for OpenStack Victoria, the image
    build will use the latter, for the simple fact that it do not consider
    the `openstack` layer (and, therefore, `deb-local-binary-openstack`).

    To get around this problem, this change seeks to add a `sources.list`
    for each build layer. By default, they are all disabled. However, if
    necessary, they can be enabled and used in image builds based on Docker
    or LOCI.

    Note: This change is the prerequisite of [4].
          The test plan with the `stx-openstackclients` image will be done
          there.

    [1] https://opendev.org/starlingx/openstack-armada-app/src/branch/f/antelope/upstream/openstack/python-openstackclient/debian/stx-openstackclient.stable_docker_image#L26-L27
    [2] https://opendev.org/starlingx/openstack-armada-app/src/branch/f/antelope/upstream/openstack/python-cinderclient/debian/patches
    [3] https://opendev.org/starlingx/openstack-armada-app/src/branch/f/antelope/upstream/openstack/python-openstackclient/debian/patches
    [4] https://review.opendev.org/c/starlingx/openstack-armada-app/+/896462

    Test Plan:
    PASS - Build `stx-debian` base image
    PASS - Build all container images with --clean and confirm that:
           1. All container images were built successfully;
           2. All container images were removed successfully.

    Partial-Bug: 2037339

    Change-Id: I36d1af990afad9fd69b723bf3a13b88673dd08ad
    Signed-off-by: Luan Nunes Utimura <email address hidden>