Comment 20 for bug 1927981

Reviewed: https://review.opendev.org/c/openstack/charm-mysql-router/+/851761
Committed: https://opendev.org/openstack/charm-mysql-router/commit/cfe6b2e3c0081fdc9c3aafec26a942e722de34a9
Submitter: "Zuul (22348)"
Branch: stable/jammy

commit cfe6b2e3c0081fdc9c3aafec26a942e722de34a9
Author: Rodrigo Barbieri <email address hidden>
Date: Mon Jul 4 17:22:02 2022 -0300

    Fix restarts during upgrade-charm hook

    Upgrade-charm code needs to make various adjustments to
    the config files and restart the mysql-router service,
    but the code is currently running config-changed and
    getting stuck in a restart loop before upgrade-charm
    is able to run to make the config adjustments and
    invoke a successful restart.

    This change adds a condition to skip the execution of
    config_changed function when upgrade-charm hook runs,
    so upgrade_charm code takes care of the adjustments.

    Also, now upgrade-charm hook is guaranteed to restart the
    mysql-router service whenever any change to the config
    file is made as part of its execution, whereas before
    it wasn't doing so when making the adjustments of the
    custom upgrade_charm function, resulting in the possibility
    of no restarts after a charm upgrade.

    This change includes the now-abandoned change:
    https://review.opendev.org/848748

    Co-Authored-By: Felipe Reyes <email address hidden>

    Closes-bug: #1980693
    Closes-bug: #1979263
    Related-bug: #1927981
    Change-Id: If9d71bdb839c9c0ee3f4b33e4d44a5c93bdd13de
    (cherry picked from commit 6df798a939c9f5e167a73f6e8c145c6ec631ac6c)