Description of problem:

We are trying to make use of the also_notifies attribute used in the Designate pools.yml in our OSP 13 deployment to signal an external DNS service of changes within zones that Designate manages. 
It was identified that this feature wasn't working in a stock deployment and after some research found that it was a bug that got fixed in the upstream community https://bugs.launchpad.net/designate/+bug/1785769
A patch has been created against python-designate-6.0.1-3.el7ost.noarch and verify that the fix in the upstream bug solved the problem. 
We'd like this patch backported to OSP13.

The following patch is verified that works against python-designate-6.0.1-3.el7ost.noarch (based on the upstream bug fix)


designate_worker_bug_589409.patch
~~~
--- a/designate/worker/service.py	2019-05-21 19:48:31.919780738 +0000
+++ b/designate/worker/service.py	2019-05-21 19:51:25.894249273 +0000
@@ -34,6 +34,12 @@
 LOG = logging.getLogger(__name__)
 CONF = cfg.CONF

+class AlsoNotifyTask(object):
+    """
+    Placeholder to define options for also_notify targets
+    """
+    pass
+

 class Service(service.RPCService, service.Service):
     RPC_API_VERSION = '1.0'
@@ -121,10 +127,20 @@

     def _do_zone_action(self, context, zone):
         pool = self.get_pool(zone.pool_id)
-        task = zonetasks.ZoneAction(
+        all_tasks = []
+        all_tasks.append(zonetasks.ZoneAction(
             self.executor, context, pool, zone, zone.action
-        )
-        return self.executor.run(task)
+        ))
+
+        # Send a NOTIFY to each also-notifies
+        for also_notify in pool.also_notifies:
+            notify_target = AlsoNotifyTask()
+            notify_target.options = {'host': also_notify.host,
+                                     'port': also_notify.port}
+            all_tasks.append(zonetasks.SendNotify(self.executor,
+                                                  zone,
+                                                  notify_target))
+        return self.executor.run(all_tasks)

     def create_zone(self, context, zone):
         """
~~~

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