Update zones masters using pool target masters.

This change enforces the update of the zone masters
for all zones that belongs to a particular pool, using
the pool's defined target(s) masters and forcing a update_zone
call.

This change also, moves the backend base class update_zone
method as an abstract method, allowing to each backend
implementation to create its own update logic. For the
case of bind9 its extended to allow running a rndc modzone
with the new given masters for the zone fixing the behavior
exposed on LP: #1879798.

Fixes-Bug: #1879798

Change-Id: I9dddd4130a0cbb29311eeb52e077e216c8c03f3a
Signed-off-by: Jorge Niedbalski <jorge.niedbalski@canonical.com>
(cherry picked from commit 3756fc5)

designate/backend/impl_bind9.py

@@ -127,6 +127,43 @@ def delete_zone(self, context, zone):
                 LOG.warning('RNDC call failure: %s', e)
                 raise
 
+    def update_zone(self, context, zone):
+        """
+        Update a DNS zone.
+
+        This will execute a rndc modzone as the zone
+        already exists but masters might need to be refreshed.
+
+        :param context: Security context information.
+        :param zone: the DNS zone.
+        """
+        LOG.debug('Update Zone')
+
+        masters = []
+        for master in self.masters:
+            host = master['host']
+            port = master['port']
+            masters.append('%s port %s' % (host, port))
+
+        # Ensure different MiniDNS instances are targeted for AXFRs
+        random.shuffle(masters)
+
+        view = 'in %s' % self._view if self._view else ''
+
+        rndc_op = [
+            'modzone',
+            '%s %s { type slave; masters { %s;}; file "slave.%s%s"; };' %
+            (zone['name'].rstrip('.'), view, '; '.join(masters), zone['name'],
+             zone['id']),
+        ]
+
+        try:
+            self._execute_rndc(rndc_op)
+        except exceptions.Backend as e:
+            LOG.warning("Error updating zone: %s", e)
+            pass
+        super().update_zone(context, zone)
+
     def _execute_rndc(self, rndc_op):
         """Execute rndc
 

designate/manage/pool.py

@@ -23,6 +23,7 @@
 from designate import exceptions
 from designate import rpc
 from designate import objects
+from designate import policy
 from designate.central import rpcapi as central_rpcapi
 from designate.manage import base
 from designate.objects.adapters import DesignateAdapter
@@ -43,6 +44,30 @@ def _startup(self):
         rpc.init(cfg.CONF)
         self.central_api = central_rpcapi.CentralAPI()
 
+    def _update_zones(self, pool):
+        LOG.info("Updating zone masters for pool: {}".format(pool.id))
+
+        def __get_masters_from_pool(pool):
+            masters = []
+            for target in pool.targets:
+                for master in target.get("masters", []):
+                    masters.append({'host': master['host'],
+                                    'port': master['port']})
+            return masters
+
+        policy.init()
+
+        self.context.all_tenants = True
+        zones = self.central_api.find_zones(
+            self.context,
+            criterion={'pool_id': pool.id})
+
+        for zone in zones:
+            zone.masters = objects.ZoneMasterList().from_list(
+                __get_masters_from_pool(pool))
+            self.central_api.update_zone(self.context,
+                                         zone)
+
     @base.args('--file', help='The path to the file the yaml output should be '
                'written to',
                default='/etc/designate/pools.yaml')
@@ -140,6 +165,9 @@ def update(self, file, delete, dry_run):
                     output_msg.append("Update Pool: %s" % pool)
                 else:
                     pool = self.central_api.update_pool(self.context, pool)
+                    # Bug: Changes in the pool targets should trigger a
+                    # zone masters update LP: #1879798.
+                    self._update_zones(pool)
 
             except exceptions.PoolNotFound:
                 pool = DesignateAdapter.parse('YAML', xpool, objects.Pool())

designate/tests/test_manage/__init__.py

@@ -0,0 +1,5 @@
+from designate.tests import TestCase
+
+
+class DesignateManageTestCase(TestCase):
+    pass

designate/tests/test_manage/test_update_pool.py

@@ -0,0 +1,65 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+from oslo_log import log as logging
+
+import mock
+from designate.tests.test_manage import DesignateManageTestCase
+from designate.manage.pool import PoolCommands
+from designate.tests import fixtures
+from designate import objects
+
+LOG = logging.getLogger(__name__)
+
+
+class UpdatePoolTestCase(DesignateManageTestCase):
+    def setUp(self):
+        super(DesignateManageTestCase, self).setUp()
+        self.stdlog = fixtures.StandardLogging()
+        self.useFixture(self.stdlog)
+
+    def hydrate_pool_targets(self, targets):
+        pool_targets = objects.PoolTargetList()
+        masters = objects.PoolTargetMasterList()
+        for target in targets:
+            masters.append(target)
+        target = objects.PoolTarget(masters=masters)
+        target.masters = masters
+        pool_targets.append(target)
+        return pool_targets
+
+    def test_update_pools_zones(self):
+        values = dict(
+            name='example.com.',
+            email='info@example.com',
+            type='PRIMARY'
+        )
+
+        zone = self.central_service.create_zone(
+            self.admin_context, zone=objects.Zone.from_dict(values))
+
+        # Ensure the correct NS Records are in place
+        pool = self.central_service.get_pool(
+            self.admin_context, zone.pool_id)
+
+        pool.targets = self.hydrate_pool_targets([objects.PoolTargetMaster(
+                  pool_target_id=pool.id,
+                  host="127.0.0.1",
+                  port="53")])
+
+        command = PoolCommands()
+        command.context = self.admin_context
+        command.central_api = self.central_service
+
+        with mock.patch.object(self.central_service,
+                               "update_zone") as mock_update_zone:
+            command._update_zones(pool)
+            mock_update_zone.assert_called_once()

designate/tests/unit/backend/test_bind9.py

@@ -65,6 +65,18 @@ def test_create_zone(self, mock_execute):
             ]
         )
 
+    @mock.patch.object(impl_bind9.Bind9Backend, '_execute_rndc')
+    def test_update_zone(self, mock_execute):
+        with fixtures.random_seed(0):
+            self.backend.update_zone(self.admin_context, self.zone)
+
+        mock_execute.assert_called_with(
+            [
+                'modzone',
+                'example.com  { type slave; masters { 192.168.1.1 port 53; 192.168.1.2 port 35;}; file "slave.example.com.cca7908b-dad4-4c50-adba-fb67d4c556e8"; };'  # noqa
+            ]
+        )
+
     @mock.patch.object(impl_bind9.Bind9Backend, '_execute_rndc')
     def test_create_zone_with_view(self, mock_execute):
         self.target['options'].append(