Make zone_purge time threshold configurable.

The default of one week for how old deleted zones
should be purged is too long. This patch makes
it 1 hour by default and adds a new config
option for it (zone-purge-time-threshold).

Change-Id: Ifc6d43ca897c218ae365b4881a2f09b61542efa4
Fixes-Bug: #1899064
Signed-off-by: Jorge Niedbalski <jorge.niedbalski@canonical.com>

src/config.yaml

@@ -89,3 +89,9 @@ options:
       override YAML files in the service's policy.d directory.  The resource
       file should be a ZIP file containing at least one yaml file with a .yaml
       or .yml extension.  If False then remove the overrides.
+  zone-purge-time-threshold:
+    type: int
+    default: 3600
+    description: |
+      Default for how old deleted zones should be (deleted_at) to be
+      purged, in seconds.

src/templates/mitaka/designate.conf

@@ -232,7 +232,7 @@ enabled_notification_handlers = {{ options.notification_handlers }}
 #batch_size = 100
 
 # How old deleted records should be (deleted_at) to be purged, in seconds
-#time_threshold = 604800  # 7 days
+time_threshold = {{ options.zone_purge_time_threshold }}
 
 #-----------------------
 # Pool Manager Service

src/templates/queens/designate.conf

@@ -235,7 +235,7 @@ enabled_notification_handlers = {{ options.notification_handlers }}
 #batch_size = 100
 
 # How old deleted records should be (deleted_at) to be purged, in seconds
-#time_threshold = 604800  # 7 days
+time_threshold = {{ options.zone_purge_time_threshold }}
 
 #-----------------------
 # Pool Manager Service

src/templates/rocky/designate.conf

@@ -323,3 +323,8 @@ backend_url = {{ coordinator_memcached.url }}
 # [hook_point:designate.api.v2.controllers.zones.get_one]
 
 {% include "parts/section-oslo-middleware" %}
+
+[producer_task:zone_purge]
+
+# How old deleted records should be (deleted_at) to be purged, in seconds
+time_threshold = {{ options.zone_purge_time_threshold }}