ocata designate-mdns fails if monasca-statd not installed

[Corey Bryant]

designate-mdns is failing on ocata if monasca-statsd is not installed.

This is without any options set in the [monasca:statsd] config section, therefore statsd is disabled in this case.

systemd[1]: Started OpenStack Designate DNSaaS mdns.
designate-mdns[16241]: Traceback (most recent call last):
designate-mdns[16241]: File "/usr/bin/designate-mdns", line 6, in <module>
designate-mdns[16241]: from designate.cmd.mdns import main
designate-mdns[16241]: File "/usr/lib/python2.7/dist-packages/designate/cmd/mdns.py", line 26, in <module>
designate-mdns[16241]: from designate.mdns import service as mdns_service
designate-mdns[16241]: File "/usr/lib/python2.7/dist-packages/designate/mdns/service.py", line 23, in <module>
designate-mdns[16241]: from designate.mdns import handler
designate-mdns[16241]: File "/usr/lib/python2.7/dist-packages/designate/mdns/handler.py", line 27, in <module>
designate-mdns[16241]: from designate.mdns import xfr
designate-mdns[16241]: File "/usr/lib/python2.7/dist-packages/designate/mdns/xfr.py", line 29, in <module>
designate-mdns[16241]: class XFRMixin(object):
designate-mdns[16241]: File "/usr/lib/python2.7/dist-packages/designate/mdns/xfr.py", line 34, in XFRMixin
designate-mdns[16241]: def zone_sync(self, context, zone, servers=None):
designate-mdns[16241]: TypeError: 'NoneType' object is not callable

It seems the TypeError occurs somewhere within the @metrics.timed decorator:

    @metrics.timed('mdns.xfr.zone_sync')
    def zone_sync(self, context, zone, servers=None):
        ...

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/425982

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/425982
Committed: https://git.openstack.org/cgit/openstack/designate/commit/?id=dc34ed43ddbb425fd4b6eb7eeb721daf7d36e147
Submitter: Jenkins
Branch: master

commit dc34ed43ddbb425fd4b6eb7eeb721daf7d36e147
Author: Alex Schultz <email address hidden>
Date: Thu Jan 26 16:58:37 2017 -0700

    Fix noop metrics timed decorator

    Previously if you did not have the monasca statds available, the @timed
    decorator would result in a NoneType error because timed was returning
    None instead of acting as a noop function wrapper. This change updates
    the NoopTimer to properly handle timed being used as a function.

    Change-Id: Ic5543b3503b24aaef960d8b7c0cb38940241cbcb
    Closes-Bug: #1659638

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/designate 4.0.0.0rc1 release candidate.