python-binary-memcached is now a hard dependency but doesn't need to be

[Corey Bryant]

See https://opendev.org/openstack/oslo.cache/commit/d229d3edb73610137d78779b12e6dc226a3c6e61

I'm having issues with the python-binary-memcached package. For ubuntu, if it is a required dependency then we need to get it into main (since oslo.ache is in main). In order to do that we need the python-binary-memcachd package to run unit tests. However the upstream repository's unit tests don't run successfully and upstream also doesn't gate PRs with unit test execution. For more on that see: https://github.com/jaysonsantos/python-binary-memcached/issues/250

Can we make it an optional dependency?
In other words, considering it is only used if sasl_enabled=True, we could allow the memcache_pool backend to continue to execute as it used to even if python-binary-memcached is not installed.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/oslo.cache/+/859874

[Launchpad Janitor (janitor)]

This bug was fixed in the package python-oslo.cache - 3.1.0-0ubuntu5

---------------
python-oslo.cache (3.1.0-0ubuntu5) kinetic; urgency=medium

  * d/p/allow-bmemcached-to-be-optional-for-memcache_pool.patch:
    Patch updated to raise unexpected ImportError.

 -- Corey Bryant <email address hidden> Mon, 03 Oct 2022 09:16:14 -0400

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/oslo.cache/+/859874
Committed: https://opendev.org/openstack/oslo.cache/commit/edd10f7a9c149f70d1d92a12d691a0d230aebba5
Submitter: "Zuul (22348)"
Branch: master

commit edd10f7a9c149f70d1d92a12d691a0d230aebba5
Author: Corey Bryant <email address hidden>
Date: Thu Sep 29 11:51:52 2022 -0400

    Allow bmemcached to be optional for memcache_pool

    This allows oslo_cache.memcache_pool to be used without the
    python-binary-memcached package being installed, as it is
    only required if sasl_enabled is set to True.

    Closes-Bug: #1991250
    Change-Id: I7e6cc83864be68e946d86b1f4b44847b95ea8b05

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/oslo.cache 3.4.0 release.