Comment 38 for bug 1927277

Reviewed: https://review.opendev.org/c/openstack/charm-ceilometer-agent/+/899056
Committed: https://opendev.org/openstack/charm-ceilometer-agent/commit/fba093189cb81454b897709caaeb2ae022029fbd
Submitter: "Zuul (22348)"
Branch: stable/ussuri

commit fba093189cb81454b897709caaeb2ae022029fbd
Author: Aurelien Lourot <email address hidden>
Date: Tue Sep 28 14:19:08 2021 +0200

    Publish releases packages map to principal charm

    For principal - subordinate plugin type relations where the
    principal Python payload imports code from packages managed by a
    subordinate, upgrades can be problematic.

    This change will allow a subordinate charm that have opted into the
    feature to inform its principal about all implemented release -
    packages combinations ahead of time. With this information in place
    the principal can do the upgrade in one operation without risk of
    charm relation RPC type processing at a critical moment.

    This is similar to
    https://review.opendev.org/c/openstack/charm-interface-keystone-domain-backend/+/781658
    https://review.opendev.org/c/openstack/charm-layer-openstack/+/781624

    Change-Id: Ibd5bdcb141fc3103ee97123ff284fb2957802eba
    Closes-Bug: #1927277
    (cherry picked from commit be45f7794504514ffbd4bc721af8f3df9a4c6038)