Specify dns_domain in dhcp_agent.ini from neutron-api

Specify the dns_domain value in dhcp_agent.ini configuration
file in order to indicate the dns search domain which should
be advertised by the dnsmasq DHCP server.

Note, for neutron-openvswitch - this only takes effect when
the enable-local-dhcp-and-metadata flag is set to true.

Change-Id: If3529cf32a6e10d44c86423151cdacdad50445f8
Implements: blueprint charms-internal-dns

hooks/charmhelpers/contrib/openstack/context.py

@@ -1393,6 +1393,10 @@ class NeutronAPIContext(OSContextGenerator):
                 'rel_key': 'enable-l3ha',
                 'default': False,
             },
+            'dns_domain': {
+                'rel_key': 'dns-domain',
+                'default': None,
+            },
         }
         ctxt = self.get_neutron_options({})
         for rid in relation_ids('neutron-plugin-api'):

hooks/neutron_ovs_context.py

@@ -156,7 +156,8 @@ class DHCPAgentContext(OSContextGenerator):
 
     def __call__(self):
         """Return the 'default_availability_zone' from the principal that this
-        ovs unit is attached to (as a subordinate).
+        ovs unit is attached to (as a subordinate) and the 'dns_domain' from
+        the neutron-plugin-api relations (if one is set).
 
         :returns: {} if no relation set, or
             {'availability_zone': availability_zone from principal relation}
@@ -181,6 +182,10 @@ class DHCPAgentContext(OSContextGenerator):
         if dnsmasq_flags:
             ctxt['dnsmasq_flags'] = config_flags_parser(dnsmasq_flags)
 
+        neutron_api_settings = NeutronAPIContext()()
+        if neutron_api_settings.get('dns_domain'):
+            ctxt['dns_domain'] = neutron_api_settings.get('dns_domain')
+
         return ctxt
 
 

templates/mitaka/dhcp_agent.ini

@@ -15,6 +15,14 @@ root_helper = sudo /usr/bin/neutron-rootwrap /etc/neutron/rootwrap.conf
 dnsmasq_config_file = /etc/neutron/dnsmasq.conf
 {% endif -%}
 
+{% if dns_domain -%}
+dns_domain = {{ dns_domain }}
+# Per LP#1583769, dhcp_domain needs to be configured in mitaka as well. Additional
+# testing shows that this has not been changed in newton, so will also
+# specify the dhcp_domain field.
+dhcp_domain = {{ dns_domain }}
+{% endif -%}
+
 enable_metadata_network = True
 enable_isolated_metadata = True
 

unit_tests/test_neutron_ovs_context.py

@@ -255,13 +255,28 @@ class DHCPAgentContextTest(CharmTestCase):
     def tearDown(self):
         super(DHCPAgentContextTest, self).tearDown()
 
-    def test_default_availability_zone_not_provided(self):
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_get')
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_ids')
+    @patch.object(charmhelpers.contrib.openstack.context, 'related_units')
+    def test_default_availability_zone_not_provided(self, _runits, _rids,
+                                                    _rget):
+        _runits.return_value = ['neutron-api/0']
+        _rids.return_value = ['rid2']
+        rdata = {
+            'neutron-security-groups': 'True',
+            'enable-dvr': 'True',
+            'l2-population': 'True',
+            'overlay-netweork-type': 'vxlan',
+            'network-device-mtu': 1500,
+            'dns-domain': 'openstack.example.'
+        }
+        _rget.side_effect = lambda *args, **kwargs: rdata
         self.relation_ids.return_value = ['rid1']
         self.related_units.return_value = ['nova-compute/0']
         self.relation_get.return_value = None
         self.assertEqual(
             context.DHCPAgentContext()(),
-            {}
+            {'dns_domain': 'openstack.example.'}
         )
         self.relation_ids.assert_called_with('neutron-plugin')
         self.relation_get.assert_called_once_with(
@@ -269,7 +284,49 @@ class DHCPAgentContextTest(CharmTestCase):
             rid='rid1',
             unit='nova-compute/0')
 
-    def test_default_availability_zone_provided(self):
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_get')
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_ids')
+    @patch.object(charmhelpers.contrib.openstack.context, 'related_units')
+    def test_default_availability_zone_provided(self, _runits, _rids, _rget):
+        _runits.return_value = ['neutron-api/0']
+        _rids.return_value = ['rid2']
+        rdata = {
+            'neutron-security-groups': 'True',
+            'enable-dvr': 'True',
+            'l2-population': 'True',
+            'overlay-netweork-type': 'vxlan',
+            'network-device-mtu': 1500,
+            'dns-domain': 'openstack.example.'
+        }
+        _rget.side_effect = lambda *args, **kwargs: rdata
+        self.relation_ids.return_value = ['rid1']
+        self.related_units.return_value = ['nova-compute/0']
+        self.relation_get.return_value = 'nova'
+        self.assertEqual(
+            context.DHCPAgentContext()(),
+            {'availability_zone': 'nova',
+             'dns_domain': 'openstack.example.'}
+        )
+        self.relation_ids.assert_called_with('neutron-plugin')
+        self.relation_get.assert_called_once_with(
+            'default_availability_zone',
+            rid='rid1',
+            unit='nova-compute/0')
+
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_get')
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_ids')
+    @patch.object(charmhelpers.contrib.openstack.context, 'related_units')
+    def test_no_dns_domain(self, _runits, _rids, _rget):
+        _runits.return_value = ['neutron-api/0']
+        _rids.return_value = ['rid2']
+        rdata = {
+            'neutron-security-groups': 'True',
+            'enable-dvr': 'True',
+            'l2-population': 'True',
+            'overlay-netweork-type': 'vxlan',
+            'network-device-mtu': 1500,
+        }
+        _rget.side_effect = lambda *args, **kwargs: rdata
         self.relation_ids.return_value = ['rid1']
         self.related_units.return_value = ['nova-compute/0']
         self.relation_get.return_value = 'nova'
@@ -283,7 +340,20 @@ class DHCPAgentContextTest(CharmTestCase):
             rid='rid1',
             unit='nova-compute/0')
 
-    def test_dnsmasq_flags(self):
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_get')
+    @patch.object(charmhelpers.contrib.openstack.context, 'relation_ids')
+    @patch.object(charmhelpers.contrib.openstack.context, 'related_units')
+    def test_dnsmasq_flags(self, _runits, _rids, _rget):
+        _runits.return_value = ['neutron-api/0']
+        _rids.return_value = ['rid2']
+        rdata = {
+            'neutron-security-groups': 'True',
+            'enable-dvr': 'True',
+            'l2-population': 'True',
+            'overlay-netweork-type': 'vxlan',
+            'network-device-mtu': 1500,
+        }
+        _rget.side_effect = lambda *args, **kwargs: rdata
         self.relation_ids.return_value = ['rid1']
         self.related_units.return_value = ['nova-compute/0']
         self.relation_get.return_value = None