Comment 13 for bug 1902264

Reviewed: https://review.opendev.org/c/openstack/charm-keystone/+/804802
Committed: https://opendev.org/openstack/charm-keystone/commit/9b8b81a0bc8406f03b2de884eeec91b8e8f2d442
Submitter: "Zuul (22348)"
Branch: master

commit 9b8b81a0bc8406f03b2de884eeec91b8e8f2d442
Author: Chris MacNaughton <email address hidden>
Date: Mon Aug 16 16:55:14 2021 -0500

    Use the application data bag to set id and id_service notifications

    When purely using relation-set from a leader, updates after
    the leader has changed can lead to old data being persisted
    on a relation in addition to newer data being set by the new
    leader. When this happens, there can be issues with services
    using old data to talk to other related services.

    This change introduces the use of the application data bag
    to ensure that all units related to keystone get the same
    data from the leader, regardless of leadership changes.
    While this change enables the application data bag for these
    relations, it still sends the per-unit relation data as well
    to maintain backwards compatibility. Charms that consume the
    identity-service and identity-notification relations will
    need an update to use the application data bag to complete
    this change.

    Partial-Bug: #1902264
    Change-Id: Iadd795fec605e7704e5a6673906452279bbecb34