Comment 2 for bug 1675143

Reviewed: https://review.openstack.org/449119
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=b2b366aa4aa2b5199ddbd8cd51019f3d8b7bccc3
Submitter: Jenkins
Branch: master

commit b2b366aa4aa2b5199ddbd8cd51019f3d8b7bccc3
Author: Chris Dent <email address hidden>
Date: Thu Mar 23 12:33:00 2017 +0000

    [placement] Don't use floats in microversion handling

    When microversioned request handling was added to placement some
    comparisons were added that treat the microversions as floats. This
    will break as soon as the right hand side of the version chnages
    from one digit to two. A float of 1.1 and 1.10 is the same. A
    version string of '1.1' and '1.10' is not.

    This patch changes the internals of version handling to always use
    Version objects which represent the versions using a name tuple
    (major=1, minor=10). It also changes the externals to expect versions
    as strings ('1.10'). Where floats were present before, these have
    been changed to strings. Where tuples have been accepted, these are
    still accepted, but strings are as well.

    This is an internal only change, users shouldn't notice any
    difference as their versions (in the openstack-api-version header)
    were always strings and we haven't made it to version 1.10, sorry
    '1.10', yet.

    If developers try to version_handler with something other than a
    version string, test runs will fail very early (at import time).

    Change-Id: Ic2b655ac4c75c6104eddecd174f193413a0764d2
    Closes-Bug: #1675143