Add enable_dhcp filter in get_network_info rpc

Add enable_dhcp, to make a filter to avoid unnecessary
net_info data transfer through rpc.

Change-Id: Ibcef366f5b1f4b7da4f47f1f538a17111da0faa1
Closes-Bug: #1552614

neutron/agent/dhcp/agent.py

@@ -410,6 +410,8 @@ class DhcpAgent(manager.Manager):
             return
 
         for subnet in network.subnets:
+            # TODO(isabek): in Y release below 'if' can be removed
+            # because only dhcp enbaled subnets are returned from server
             if subnet.enable_dhcp:
                 if self.call_driver('enable', network):
                     self.update_isolated_metadata_proxy(network)

neutron/api/rpc/handlers/dhcp_rpc.py

@@ -73,10 +73,11 @@ class DhcpRpcCallback(object):
     #           the major version as above applies here too.
     #     1.7 - Add get_networks
     #     1.8 - Add get_dhcp_port
+    #     1.9 - get_network_info returns info with only DHCP enabled subnets
 
     target = oslo_messaging.Target(
         namespace=constants.RPC_NAMESPACE_DHCP_PLUGIN,
-        version='1.8')
+        version='1.9')
 
     def _get_active_networks(self, context, **kwargs):
         """Retrieve and return a list of the active networks."""
@@ -207,7 +208,11 @@ class DhcpRpcCallback(object):
         return networks
 
     def get_network_info(self, context, **kwargs):
-        """Retrieve and return extended information about a network."""
+        """Retrieve and return information about a network.
+
+        Retrieve and return extended information about a network
+        with only DHCP enabled subnets.
+        """
         network_id = kwargs.get('network_id')
         host = kwargs.get('host')
         LOG.debug('Network %(network_id)s requested from '
@@ -220,8 +225,8 @@ class DhcpRpcCallback(object):
             LOG.debug("Network %s could not be found, it might have "
                       "been deleted concurrently.", network_id)
             return
-        filters = dict(network_id=[network_id])
-        subnets = plugin.get_subnets(context, filters=filters)
+        subnet_filters = {'network_id': [network_id], 'enable_dhcp': [True]}
+        subnets = plugin.get_subnets(context, filters=subnet_filters)
         seg_plug = directory.get_plugin(
             segment_ext.SegmentPluginBase.get_plugin_type())
         nonlocal_subnets = []
@@ -247,7 +252,8 @@ class DhcpRpcCallback(object):
         network['subnets'] = sorted(subnets, key=operator.itemgetter('id'))
         network['non_local_subnets'] = sorted(nonlocal_subnets,
                                               key=operator.itemgetter('id'))
-        network['ports'] = plugin.get_ports(context, filters=filters)
+        port_filters = {'network_id': [network_id]}
+        network['ports'] = plugin.get_ports(context, filters=port_filters)
         return network
 
     @db_api.retry_db_errors

neutron/tests/unit/api/rpc/handlers/test_dhcp_rpc.py

@@ -245,6 +245,12 @@ class TestDhcpRpcCallback(base.BaseTestCase):
         self.assertEqual(retval['non_local_subnets'],
                          sorted_nonlocal_subnet_retval)
         self.assertEqual(retval['ports'], port_retval)
+        subnet_filters = {'network_id': [network_retval['id']],
+                          'enable_dhcp': [True]}
+        self.plugin.assert_has_calls(
+            [mock.call.get_network(mock.ANY, 'a'),
+             mock.call.get_subnets(mock.ANY, filters=subnet_filters),
+             mock.call.get_ports(mock.ANY, filters={'network_id': ['a']})])
 
     def test_get_network_info(self):
         self._test_get_network_info()