Comment 19 for bug 1596620

Reviewed: https://review.openstack.org/340017
Committed: https://git.openstack.org/cgit/openstack/openstack-ansible-lxc_hosts/commit/?id=8eeddc39d7b671d104e02d50b4d933a5ea3f77b1
Submitter: Jenkins
Branch: stable/mitaka

commit 8eeddc39d7b671d104e02d50b4d933a5ea3f77b1
Author: Jesse Pretorius <email address hidden>
Date: Wed May 4 09:43:38 2016 +0100

    Change pip install task state to 'latest'

    Currently all pip install tasks only require the package to be
    present. This means that when an environment undergoes a minor
    upgrade the package is not upgraded to the same version that
    was tested with. This ultimately results in a deployed
    environment that does not match the tested environment.

    While for the services installed into venvs this is not an
    issue, it does affect those which do not use venvs and any
    packages which are installed outside of a venv or on top
    of a venv.

    This patch changes the behaviour to ensure that the install
    task will always use the latest available package. In
    developer_mode this will mean using the version specified
    in upper-constraints, and in an integrated build this will
    mean the version which is available in the wheel repo's
    folder for the tag.

    Related-Bug: 1596620

    Change-Id: I24f9cdf7eb218051b4e75f910ffb5ae280aab976
    (cherry picked from commit 50ded911a5cc50079385216dd13715af1224f631)