Comment 11 for bug 1820892

Reviewed: https://review.openstack.org/645592
Committed: https://git.openstack.org/cgit/openstack-dev/devstack/commit/?id=9c1b7a5e6ac842d99f11b9be3042ed3499eb156f
Submitter: Zuul
Branch: stable/rocky

commit 9c1b7a5e6ac842d99f11b9be3042ed3499eb156f
Author: Matt Riedemann <email address hidden>
Date: Tue Mar 19 15:04:12 2019 -0400

    Ease python 3 classifier check in check_python3_support_for_package_local

    This makes the grep match in check_python3_support_for_package_local
    the same as check_python3_support_for_package_remote.

    Change I0349de2026c49279ba7f262d5e86d37018d66326 in grenade started
    setting the PYTHON3_VERSION variable, and then we recently started
    using bionic nodes everywhere which means we're running python 3.6.

    The etcd3gw package has a python 3 and 3.5 classifier, but not 3.6:

    https://pypi.org/project/etcd3gw/

    The pip_install function code that is dealing with installing py3
    packages is hitting a problem installing etcd3gw if the package is
    local because of the more restrictive grep in the
    check_python3_support_for_package_local function, and since
    PYTHON3_VERSION=3.6 now, we don't install from py3 and install
    etcd3gw on python 2.7 which makes services like cinder-volume and
    cinder-backup, which use etcd3gw, fail when they are running under
    python 3 (they get module import errors).

    This simply removes the $ restriction on the grep. Looking at the
    change that added those local/remote functions:

      I243ea4b76f0d5ef57a03b5b0798a05468ee6de9b

    There is no explanation for the difference, it just said:

      Also, since not many packages are classified correctly, fallback
      to looking for just "Programming Language :: Python :: 3" and
      log a message for the package to highlight the problem.

    So that's what this change does.

    Note that alternatives would be:

    1. Update the etcd3gw package to add the 3.6 classifier and do
       a release (this should probably happen anyway).

    2. Add etcd3gw to ENABLED_PYTHON3_PACKAGES but that would be a
       short-term hack workaround.

    Change-Id: Icd3768870ba0f1659bb2e6f002043d975047b73e
    Closes-Bug: #1820892
    (cherry picked from commit ddb6179b0479ea9478cf2a146fe9b0d7592acaec)