commit 881620bd6476d008b218721b70807deca451b8c6
Author: Adrien Cunin <adrien.cunin@springernature.com>
Date:   Tue Oct 13 17:55:31 2020 +0200

    Enable notifications when Designate is enabled
    
    Change-Id: I4953ee9de704c90dac67a70f9296062e5a071a77

diff --git a/templates/nova.conf.j2 b/templates/nova.conf.j2
index e36c328..b058399 100644
--- a/templates/nova.conf.j2
+++ b/templates/nova.conf.j2
@@ -51,12 +51,15 @@ instance_usage_audit_period = hour
 
 # Notifications
 [oslo_messaging_notifications]
-{% set notification_topics = ['notifications'] %}
+{% set notification_topics = [] %}
+{% if nova_ceilometer_enabled %}
+{%   set _ = notification_topics.append('notifications') %}
+{% endif %}
 {% if nova_designate_enabled %}
 {%   set _ = notification_topics.append(nova_notifications_designate) %}
 {% endif %}
 topics = {{ notification_topics | join(',') }}
-driver = {{ (nova_ceilometer_enabled | bool) | ternary('messagingv2', 'noop') }}
+driver = {{ (notification_topics | length > 0) | ternary('messagingv2', 'noop') }}
 transport_url = {{ nova_oslomsg_notify_transport }}://{% for host in nova_oslomsg_notify_servers.split(',') %}{{ nova_oslomsg_notify_userid }}:{{ nova_oslomsg_notify_password }}@{{ host }}:{{ nova_oslomsg_notify_port }}{% if not loop.last %},{% else %}/{{ nova_oslomsg_notify_vhost }}{% if nova_oslomsg_notify_use_ssl | bool %}?ssl=1{% else %}?ssl=0{% endif %}{% endif %}{% endfor %}