Avoid performing extra query for fetching mac learning binding

Bug 1214879

Add a relationship performing eager load in the Port model, thus preventing
the 'extend' function from performing an extra query.
This patch also replaces assertTrue with assertEqual in unit tests as it
needs to evaluate whether the value of the mac_learning_enabled attribute
is equal to the boolean literal True, whereas assertTrue verifies that the
expression passed to it evaluates to True. This means that any value but
False will be enough for the test to pass, which is not correct.

Change-Id: I03345ef3a125fdfa1ec7f6c3363d76efc12ced82

diff --git a/neutron/plugins/nicira/NeutronPlugin.py b/neutron/plugins/nicira/NeutronPlugin.py
index a08ccbcb307c6f06ab713ae7cf1f0fdb733479c2..131f856c057fe6fbe2b2094ca7600067221db178 100644 (file)
--- a/neutron/plugins/nicira/NeutronPlugin.py
+++ b/neutron/plugins/nicira/NeutronPlugin.py
@@ -1228,8 +1228,6 @@ class NvpPluginV2(db_base_plugin_v2.NeutronDbPluginV2,
         with context.session.begin(subtransactions=True):
             neutron_lports = super(NvpPluginV2, self).get_ports(
                 context, filters)
-            for neutron_lport in neutron_lports:
-                self._extend_port_mac_learning_state(context, neutron_lport)
         if (filters.get('network_id') and len(filters.get('network_id')) and
             self._network_is_external(context, filters['network_id'][0])):
             # Do not perform check on NVP platform
@@ -1422,6 +1420,9 @@ class NvpPluginV2(db_base_plugin_v2.NeutronDbPluginV2,
         with context.session.begin(subtransactions=True):
             ret_port = super(NvpPluginV2, self).update_port(
                 context, id, port)
+            # Save current mac learning state to check whether it's
+            # being updated or not
+            old_mac_learning_state = ret_port.get(mac_ext.MAC_LEARNING)
             # copy values over - except fixed_ips as
             # they've alreaby been processed
             port['port'].pop('fixed_ips', None)
@@ -1459,15 +1460,11 @@ class NvpPluginV2(db_base_plugin_v2.NeutronDbPluginV2,
                 context, ret_port)
             # Populate the mac learning attribute
             new_mac_learning_state = port['port'].get(mac_ext.MAC_LEARNING)
-            old_mac_learning_state = self._get_mac_learning_state(context, id)
             if (new_mac_learning_state is not None and
                 old_mac_learning_state != new_mac_learning_state):
                 self._update_mac_learning_state(context, id,
                                                 new_mac_learning_state)
                 ret_port[mac_ext.MAC_LEARNING] = new_mac_learning_state
-            elif (new_mac_learning_state is None and
-                  old_mac_learning_state is not None):
-                ret_port[mac_ext.MAC_LEARNING] = old_mac_learning_state
             self._delete_port_queue_mapping(context, ret_port['id'])
             self._process_port_queue_mapping(context, ret_port)
             LOG.warn(_("Update port request: %s"), port)
@@ -1561,7 +1558,6 @@ class NvpPluginV2(db_base_plugin_v2.NeutronDbPluginV2,
             neutron_db_port = super(NvpPluginV2, self).get_port(context,
                                                                 id, fields)
             self._extend_port_qos_queue(context, neutron_db_port)
-            self._extend_port_mac_learning_state(context, neutron_db_port)
 
             if self._network_is_external(context,
                                          neutron_db_port['network_id']):

diff --git a/neutron/plugins/nicira/dbexts/maclearning.py b/neutron/plugins/nicira/dbexts/maclearning.py
index 909fc56dd90c2dbbc07d19c85fed453e0234c9a8..cf89485c0c62d02b70827237aff80ef2ab6f37de 100644 (file)
--- a/neutron/plugins/nicira/dbexts/maclearning.py
+++ b/neutron/plugins/nicira/dbexts/maclearning.py
@@ -16,9 +16,13 @@
 #
 
 import sqlalchemy as sa
+from sqlalchemy import orm
 from sqlalchemy.orm import exc
 
+from neutron.api.v2 import attributes
+from neutron.db import db_base_plugin_v2
 from neutron.db import model_base
+from neutron.db import models_v2
 from neutron.openstack.common import log as logging
 from neutron.plugins.nicira.extensions import maclearning as mac
 
@@ -32,6 +36,13 @@ class MacLearningState(model_base.BASEV2):
                         primary_key=True)
     mac_learning_enabled = sa.Column(sa.Boolean(), nullable=False)
 
+    # Add a relationship to the Port model using the backref attribute.
+    # This will instruct SQLAlchemy to eagerly load this association.
+    port = orm.relationship(
+        models_v2.Port,
+        backref=orm.backref("mac_learning_state", lazy='joined',
+                            uselist=False, cascade='delete'))
+
 
 class MacLearningDbMixin(object):
     """Mixin class for mac learning."""
@@ -41,18 +52,14 @@ class MacLearningDbMixin(object):
                mac.MAC_LEARNING: port[mac.MAC_LEARNING]}
         return self._fields(res, fields)
 
-    def _get_mac_learning_state(self, context, port_id):
-        try:
-            query = self._model_query(context, MacLearningState)
-            state = query.filter(MacLearningState.port_id == port_id).one()
-        except exc.NoResultFound:
-            return None
-        return state[mac.MAC_LEARNING]
+    def _extend_port_mac_learning_state(self, port_res, port_db):
+        state = port_db.mac_learning_state
+        if state and state.mac_learning_enabled:
+            port_res[mac.MAC_LEARNING] = state.mac_learning_enabled
 
-    def _extend_port_mac_learning_state(self, context, port):
-        state = self._get_mac_learning_state(context, port['id'])
-        if state:
-            port[mac.MAC_LEARNING] = state
+    # Register dict extend functions for ports
+    db_base_plugin_v2.NeutronDbPluginV2.register_dict_extend_funcs(
+        attributes.PORTS, [_extend_port_mac_learning_state])
 
     def _update_mac_learning_state(self, context, port_id, enabled):
         try:

diff --git a/neutron/tests/unit/nicira/test_maclearning.py b/neutron/tests/unit/nicira/test_maclearning.py
index 6b169b67f8ec087e9d21f47b461e016bc0d58473..9534ccae0bea265e97b023af104821e48d751050 100644 (file)
--- a/neutron/tests/unit/nicira/test_maclearning.py
+++ b/neutron/tests/unit/nicira/test_maclearning.py
@@ -91,15 +91,18 @@ class MacLearningDBTestCase(test_db_plugin.NeutronDbPluginV2TestCase):
     def test_create_with_mac_learning(self):
         with self.port(arg_list=('mac_learning_enabled',),
                        mac_learning_enabled=True) as port:
+            # Validate create operation response
+            self.assertEqual(True, port['port']['mac_learning_enabled'])
+            # Verify that db operation successfully set mac learning state
             req = self.new_show_request('ports', port['port']['id'], self.fmt)
             sport = self.deserialize(self.fmt, req.get_response(self.api))
-            self.assertTrue(sport['port']['mac_learning_enabled'])
+            self.assertEqual(True, sport['port']['mac_learning_enabled'])
 
-    def test_create_port_without_mac_learning(self):
+    def test_create_and_show_port_without_mac_learning(self):
         with self.port() as port:
             req = self.new_show_request('ports', port['port']['id'], self.fmt)
             sport = self.deserialize(self.fmt, req.get_response(self.api))
-            self.assertNotIn('mac_learning', sport['port'])
+            self.assertNotIn('mac_learning_enabled', sport['port'])
 
     def test_update_port_with_mac_learning(self):
         with self.port(arg_list=('mac_learning_enabled',),
@@ -107,7 +110,7 @@ class MacLearningDBTestCase(test_db_plugin.NeutronDbPluginV2TestCase):
             data = {'port': {'mac_learning_enabled': True}}
             req = self.new_update_request('ports', data, port['port']['id'])
             res = self.deserialize(self.fmt, req.get_response(self.api))
-            self.assertTrue(res['port']['mac_learning_enabled'])
+            self.assertEqual(True, res['port']['mac_learning_enabled'])
 
     def test_update_preexisting_port_with_mac_learning(self):
         with self.port() as port:
@@ -116,8 +119,13 @@ class MacLearningDBTestCase(test_db_plugin.NeutronDbPluginV2TestCase):
             self.assertNotIn('mac_learning_enabled', sport['port'])
             data = {'port': {'mac_learning_enabled': True}}
             req = self.new_update_request('ports', data, port['port']['id'])
+            # Validate update operation response
             res = self.deserialize(self.fmt, req.get_response(self.api))
-            self.assertTrue(res['port']['mac_learning_enabled'])
+            self.assertEqual(True, res['port']['mac_learning_enabled'])
+            # Verify that db operation successfully updated mac learning state
+            req = self.new_show_request('ports', port['port']['id'], self.fmt)
+            sport = self.deserialize(self.fmt, req.get_response(self.api))
+            self.assertEqual(True, sport['port']['mac_learning_enabled'])
 
     def test_list_ports(self):
         # for this test we need to enable overlapping ips
@@ -129,4 +137,10 @@ class MacLearningDBTestCase(test_db_plugin.NeutronDbPluginV2TestCase):
                                self.port(arg_list=('mac_learning_enabled',),
                                          mac_learning_enabled=True)):
             for port in self._list('ports')['ports']:
-                self.assertTrue(port['mac_learning_enabled'])
+                self.assertEqual(True, port['mac_learning_enabled'])
+
+    def test_show_port(self):
+        with self.port(arg_list=('mac_learning_enabled',),
+                       mac_learning_enabled=True) as p:
+            port_res = self._show('ports', p['port']['id'])['port']
+            self.assertEqual(True, port_res['mac_learning_enabled'])