From: Kevin Benton <blak111@gmail.com>
Date: Sun, 6 Jul 2014 07:00:23 +0000 (-0700)
Subject: Return a tuple of None's instead of one None
X-Git-Url: https://review.fuel-infra.org/gitweb?a=commitdiff_plain;h=a84a8a5d83f545d0c00b7a83ad91b52dc31c1194;p=openstack-build%2Fneutron-build.git

Return a tuple of None's instead of one None

The expected return value of _commit_port_binding is something that
can be unpacked into two values. This changes the condition where a
concurrent delete was detected to return a 2-tuple of None's
instead of a bare None to prevent an iterable error.

Closes-Bug: #1342880
Change-Id: I9d3a51eab33819ffda6a65a00c3b5d1006a3577e
---

diff --git a/neutron/plugins/ml2/plugin.py b/neutron/plugins/ml2/plugin.py
index 0eb7b809e..e3d070b3d 100644
--- a/neutron/plugins/ml2/plugin.py
+++ b/neutron/plugins/ml2/plugin.py
@@ -356,7 +356,7 @@ class Ml2Plugin(db_base_plugin_v2.NeutronDbPluginV2,
                                                                   port_id)
             if not port_db:
                 # The port has been deleted concurrently.
-                return
+                return (None, None)
             oport = self._make_port_dict(port_db)
             port = self._make_port_dict(port_db)
             network = self.get_network(plugin_context, port['network_id'])
diff --git a/neutron/tests/unit/ml2/test_ml2_plugin.py b/neutron/tests/unit/ml2/test_ml2_plugin.py
index 929d5dbd2..dbe93f456 100644
--- a/neutron/tests/unit/ml2/test_ml2_plugin.py
+++ b/neutron/tests/unit/ml2/test_ml2_plugin.py
@@ -28,7 +28,9 @@ from neutron import manager
 from neutron.plugins.common import constants as service_constants
 from neutron.plugins.ml2.common import exceptions as ml2_exc
 from neutron.plugins.ml2 import config
+from neutron.plugins.ml2 import db as ml2_db
 from neutron.plugins.ml2 import driver_api
+from neutron.plugins.ml2 import driver_context
 from neutron.plugins.ml2 import plugin as ml2_plugin
 from neutron.tests.unit import _test_extension_portbindings as test_bindings
 from neutron.tests.unit.ml2.drivers import mechanism_logger as mech_logger
@@ -225,6 +227,29 @@ class TestMl2PortBinding(Ml2PluginV2TestCase,
             port = self._show('ports', port_id)['port']
             self._check_port_binding_profile(port)
 
+    def test_return_on_concurrent_delete_and_binding(self):
+        # create a port and delete it so we have an expired mechanism context
+        with self.port() as port:
+            plugin = manager.NeutronManager.get_plugin()
+            binding = ml2_db.get_locked_port_and_binding(self.context.session,
+                                                         port['port']['id'])[1]
+            binding['host'] = 'test'
+            mech_context = driver_context.PortContext(
+                plugin, self.context, port['port'],
+                plugin.get_network(self.context, port['port']['network_id']),
+                binding)
+        with contextlib.nested(
+            mock.patch('neutron.plugins.ml2.plugin.'
+                       'db.get_locked_port_and_binding',
+                       return_value=(None, None)),
+            mock.patch('neutron.plugins.ml2.plugin.Ml2Plugin._make_port_dict')
+        ) as (glpab_mock, mpd_mock):
+            plugin._bind_port_if_needed(mech_context)
+            # called during deletion to get port
+            self.assertTrue(glpab_mock.mock_calls)
+            # should have returned before calling _make_port_dict
+            self.assertFalse(mpd_mock.mock_calls)
+
 
 class TestMl2PortBindingNoSG(TestMl2PortBinding):
     HAS_PORT_FILTER = False