merge trunk

13 files changed, 506 insertions, 22 deletions

diff --git a/nova/tests/api/openstack/fakes.py b/nova/tests/api/openstack/fakes.py
index 17d6d591c..62e44ba96 100644
--- a/nova/tests/api/openstack/fakes.py
+++ b/nova/tests/api/openstack/fakes.py
@@ -16,7 +16,6 @@
 #    under the License.
 
 import copy
-import datetime
 import json
 import random
 import string
@@ -256,7 +255,7 @@ class FakeAuthDatabase(object):
 
     @staticmethod
     def auth_token_create(context, token):
-        fake_token = FakeToken(created_at=datetime.datetime.now(), **token)
+        fake_token = FakeToken(created_at=utils.utcnow(), **token)
         FakeAuthDatabase.data[fake_token.token_hash] = fake_token
         FakeAuthDatabase.data['id_%i' % fake_token.id] = fake_token
         return fake_token
diff --git a/nova/tests/api/openstack/test_images.py b/nova/tests/api/openstack/test_images.py
index 9f1f28611..93b402081 100644
--- a/nova/tests/api/openstack/test_images.py
+++ b/nova/tests/api/openstack/test_images.py
@@ -22,7 +22,6 @@ and as a WSGI layer
 
 import copy
 import json
-import datetime
 import os
 import shutil
 import tempfile
diff --git a/nova/tests/api/openstack/test_servers.py b/nova/tests/api/openstack/test_servers.py
index 3acdf3816..28ad4a417 100644
--- a/nova/tests/api/openstack/test_servers.py
+++ b/nova/tests/api/openstack/test_servers.py
@@ -16,7 +16,6 @@
 #    under the License.
 
 import base64
-import datetime
 import json
 import unittest
 from xml.dom import minidom
@@ -29,6 +28,7 @@ from nova import db
 from nova import exception
 from nova import flags
 from nova import test
+from nova import utils
 import nova.api.openstack
 from nova.api.openstack import servers
 import nova.compute.api
@@ -115,9 +115,9 @@ def stub_instance(id, user_id=1, private_address=None, public_addresses=None,
         "user_data": "",
         "reservation_id": "",
         "mac_address": "",
-        "scheduled_at": datetime.datetime.now(),
-        "launched_at": datetime.datetime.now(),
-        "terminated_at": datetime.datetime.now(),
+        "scheduled_at": utils.utcnow(),
+        "launched_at": utils.utcnow(),
+        "terminated_at": utils.utcnow(),
         "availability_zone": "",
         "display_name": "server%s" % id,
         "display_description": "",
diff --git a/nova/tests/scheduler/__init__.py b/nova/tests/scheduler/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/nova/tests/scheduler/__init__.py
diff --git a/nova/tests/scheduler/test_host_filter.py b/nova/tests/scheduler/test_host_filter.py
new file mode 100644
index 000000000..07817cc5a
--- /dev/null
+++ b/nova/tests/scheduler/test_host_filter.py
@@ -0,0 +1,206 @@
+# Copyright 2011 OpenStack LLC.
+# All Rights Reserved.
+#
+#    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.
+"""
+Tests For Scheduler Host Filters.
+"""
+
+import json
+
+from nova import exception
+from nova import flags
+from nova import test
+from nova.scheduler import host_filter
+
+FLAGS = flags.FLAGS
+
+
+class FakeZoneManager:
+    pass
+
+
+class HostFilterTestCase(test.TestCase):
+    """Test case for host filters."""
+
+    def _host_caps(self, multiplier):
+        # Returns host capabilities in the following way:
+        # host1 = memory:free 10 (100max)
+        #         disk:available 100 (1000max)
+        # hostN = memory:free 10 + 10N
+        #         disk:available 100 + 100N
+        # in other words: hostN has more resources than host0
+        # which means ... don't go above 10 hosts.
+        return {'host_name-description': 'XenServer %s' % multiplier,
+                'host_hostname': 'xs-%s' % multiplier,
+                'host_memory_total': 100,
+                'host_memory_overhead': 10,
+                'host_memory_free': 10 + multiplier * 10,
+                'host_memory_free-computed': 10 + multiplier * 10,
+                'host_other-config': {},
+                'host_ip_address': '192.168.1.%d' % (100 + multiplier),
+                'host_cpu_info': {},
+                'disk_available': 100 + multiplier * 100,
+                'disk_total': 1000,
+                'disk_used': 0,
+                'host_uuid': 'xxx-%d' % multiplier,
+                'host_name-label': 'xs-%s' % multiplier}
+
+    def setUp(self):
+        self.old_flag = FLAGS.default_host_filter
+        FLAGS.default_host_filter = \
+                            'nova.scheduler.host_filter.AllHostsFilter'
+        self.instance_type = dict(name='tiny',
+                memory_mb=50,
+                vcpus=10,
+                local_gb=500,
+                flavorid=1,
+                swap=500,
+                rxtx_quota=30000,
+                rxtx_cap=200)
+
+        self.zone_manager = FakeZoneManager()
+        states = {}
+        for x in xrange(10):
+            states['host%02d' % (x + 1)] = {'compute': self._host_caps(x)}
+        self.zone_manager.service_states = states
+
+    def tearDown(self):
+        FLAGS.default_host_filter = self.old_flag
+
+    def test_choose_filter(self):
+        # Test default filter ...
+        hf = host_filter.choose_host_filter()
+        self.assertEquals(hf._full_name(),
+                        'nova.scheduler.host_filter.AllHostsFilter')
+        # Test valid filter ...
+        hf = host_filter.choose_host_filter(
+                        'nova.scheduler.host_filter.InstanceTypeFilter')
+        self.assertEquals(hf._full_name(),
+                        'nova.scheduler.host_filter.InstanceTypeFilter')
+        # Test invalid filter ...
+        try:
+            host_filter.choose_host_filter('does not exist')
+            self.fail("Should not find host filter.")
+        except exception.SchedulerHostFilterNotFound:
+            pass
+
+    def test_all_host_filter(self):
+        hf = host_filter.AllHostsFilter()
+        cooked = hf.instance_type_to_filter(self.instance_type)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+        self.assertEquals(10, len(hosts))
+        for host, capabilities in hosts:
+            self.assertTrue(host.startswith('host'))
+
+    def test_instance_type_filter(self):
+        hf = host_filter.InstanceTypeFilter()
+        # filter all hosts that can support 50 ram and 500 disk
+        name, cooked = hf.instance_type_to_filter(self.instance_type)
+        self.assertEquals('nova.scheduler.host_filter.InstanceTypeFilter',
+                          name)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+        self.assertEquals(6, len(hosts))
+        just_hosts = [host for host, caps in hosts]
+        just_hosts.sort()
+        self.assertEquals('host05', just_hosts[0])
+        self.assertEquals('host10', just_hosts[5])
+
+    def test_json_filter(self):
+        hf = host_filter.JsonFilter()
+        # filter all hosts that can support 50 ram and 500 disk
+        name, cooked = hf.instance_type_to_filter(self.instance_type)
+        self.assertEquals('nova.scheduler.host_filter.JsonFilter', name)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+        self.assertEquals(6, len(hosts))
+        just_hosts = [host for host, caps in hosts]
+        just_hosts.sort()
+        self.assertEquals('host05', just_hosts[0])
+        self.assertEquals('host10', just_hosts[5])
+
+        # Try some custom queries
+
+        raw = ['or',
+                   ['and',
+                       ['<', '$compute.host_memory_free', 30],
+                       ['<', '$compute.disk_available', 300]
+                   ],
+                   ['and',
+                       ['>', '$compute.host_memory_free', 70],
+                       ['>', '$compute.disk_available', 700]
+                   ]
+              ]
+        cooked = json.dumps(raw)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+
+        self.assertEquals(5, len(hosts))
+        just_hosts = [host for host, caps in hosts]
+        just_hosts.sort()
+        for index, host in zip([1, 2, 8, 9, 10], just_hosts):
+            self.assertEquals('host%02d' % index, host)
+
+        raw = ['not',
+                  ['=', '$compute.host_memory_free', 30],
+              ]
+        cooked = json.dumps(raw)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+
+        self.assertEquals(9, len(hosts))
+        just_hosts = [host for host, caps in hosts]
+        just_hosts.sort()
+        for index, host in zip([1, 2, 4, 5, 6, 7, 8, 9, 10], just_hosts):
+            self.assertEquals('host%02d' % index, host)
+
+        raw = ['in', '$compute.host_memory_free', 20, 40, 60, 80, 100]
+        cooked = json.dumps(raw)
+        hosts = hf.filter_hosts(self.zone_manager, cooked)
+
+        self.assertEquals(5, len(hosts))
+        just_hosts = [host for host, caps in hosts]
+        just_hosts.sort()
+        for index, host in zip([2, 4, 6, 8, 10], just_hosts):
+            self.assertEquals('host%02d' % index, host)
+
+        # Try some bogus input ...
+        raw = ['unknown command', ]
+        cooked = json.dumps(raw)
+        try:
+            hf.filter_hosts(self.zone_manager, cooked)
+            self.fail("Should give KeyError")
+        except KeyError, e:
+            pass
+
+        self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps([])))
+        self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps({})))
+        self.assertTrue(hf.filter_hosts(self.zone_manager, json.dumps(
+                ['not', True, False, True, False]
+            )))
+
+        try:
+            hf.filter_hosts(self.zone_manager, json.dumps(
+                'not', True, False, True, False
+            ))
+            self.fail("Should give KeyError")
+        except KeyError, e:
+            pass
+
+        self.assertFalse(hf.filter_hosts(self.zone_manager,
+                json.dumps(['=', '$foo', 100])))
+        self.assertFalse(hf.filter_hosts(self.zone_manager,
+                json.dumps(['=', '$.....', 100])))
+        self.assertFalse(hf.filter_hosts(self.zone_manager,
+                json.dumps(
+            ['>', ['and', ['or', ['not', ['<', ['>=', ['<=', ['in', ]]]]]]]])))
+
+        self.assertFalse(hf.filter_hosts(self.zone_manager,
+                json.dumps(['=', {}, ['>', '$missing....foo']])))
diff --git a/nova/tests/scheduler/test_least_cost_scheduler.py b/nova/tests/scheduler/test_least_cost_scheduler.py
new file mode 100644
index 000000000..506fa62fb
--- /dev/null
+++ b/nova/tests/scheduler/test_least_cost_scheduler.py
@@ -0,0 +1,144 @@
+# Copyright 2011 OpenStack LLC.
+# All Rights Reserved.
+#
+#    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.
+"""
+Tests For Least Cost Scheduler
+"""
+
+from nova import flags
+from nova import test
+from nova.scheduler import least_cost
+from nova.tests.scheduler import test_zone_aware_scheduler
+
+MB = 1024 * 1024
+FLAGS = flags.FLAGS
+
+
+class FakeHost(object):
+    def __init__(self, host_id, free_ram, io):
+        self.id = host_id
+        self.free_ram = free_ram
+        self.io = io
+
+
+class WeightedSumTestCase(test.TestCase):
+    def test_empty_domain(self):
+        domain = []
+        weighted_fns = []
+        result = least_cost.weighted_sum(domain, weighted_fns)
+        expected = []
+        self.assertEqual(expected, result)
+
+    def test_basic_costing(self):
+        hosts = [
+            FakeHost(1, 512 * MB, 100),
+            FakeHost(2, 256 * MB, 400),
+            FakeHost(3, 512 * MB, 100)
+        ]
+
+        weighted_fns = [
+            (1, lambda h: h.free_ram),  # Fill-first, free_ram is a *cost*
+            (2, lambda h: h.io),  # Avoid high I/O
+        ]
+
+        costs = least_cost.weighted_sum(
+            domain=hosts, weighted_fns=weighted_fns)
+
+        # Each 256 MB unit of free-ram contributes 0.5 points by way of:
+        #   cost = weight * (score/max_score) = 1 * (256/512) = 0.5
+        # Each 100 iops of IO adds 0.5 points by way of:
+        #   cost = 2 * (100/400) = 2 * 0.25 = 0.5
+        expected = [1.5, 2.5, 1.5]
+        self.assertEqual(expected, costs)
+
+
+class LeastCostSchedulerTestCase(test.TestCase):
+    def setUp(self):
+        super(LeastCostSchedulerTestCase, self).setUp()
+
+        class FakeZoneManager:
+            pass
+
+        zone_manager = FakeZoneManager()
+
+        states = test_zone_aware_scheduler.fake_zone_manager_service_states(
+            num_hosts=10)
+        zone_manager.service_states = states
+
+        self.sched = least_cost.LeastCostScheduler()
+        self.sched.zone_manager = zone_manager
+
+    def tearDown(self):
+        super(LeastCostSchedulerTestCase, self).tearDown()
+
+    def assertWeights(self, expected, num, request_spec, hosts):
+        weighted = self.sched.weigh_hosts(num, request_spec, hosts)
+        self.assertDictListMatch(weighted, expected, approx_equal=True)
+
+    def test_no_hosts(self):
+        num = 1
+        request_spec = {}
+        hosts = []
+
+        expected = []
+        self.assertWeights(expected, num, request_spec, hosts)
+
+    def test_noop_cost_fn(self):
+        FLAGS.least_cost_scheduler_cost_functions = [
+            'nova.scheduler.least_cost.noop_cost_fn'
+        ]
+        FLAGS.noop_cost_fn_weight = 1
+
+        num = 1
+        request_spec = {}
+        hosts = self.sched.filter_hosts(num, request_spec)
+
+        expected = [dict(weight=1, hostname=hostname)
+                    for hostname, caps in hosts]
+        self.assertWeights(expected, num, request_spec, hosts)
+
+    def test_cost_fn_weights(self):
+        FLAGS.least_cost_scheduler_cost_functions = [
+            'nova.scheduler.least_cost.noop_cost_fn'
+        ]
+        FLAGS.noop_cost_fn_weight = 2
+
+        num = 1
+        request_spec = {}
+        hosts = self.sched.filter_hosts(num, request_spec)
+
+        expected = [dict(weight=2, hostname=hostname)
+                    for hostname, caps in hosts]
+        self.assertWeights(expected, num, request_spec, hosts)
+
+    def test_fill_first_cost_fn(self):
+        FLAGS.least_cost_scheduler_cost_functions = [
+            'nova.scheduler.least_cost.fill_first_cost_fn'
+        ]
+        FLAGS.fill_first_cost_fn_weight = 1
+
+        num = 1
+        request_spec = {}
+        hosts = self.sched.filter_hosts(num, request_spec)
+
+        expected = []
+        for idx, (hostname, caps) in enumerate(hosts):
+            # Costs are normalized so over 10 hosts, each host with increasing
+            # free ram will cost 1/N more. Since the lowest cost host has some
+            # free ram, we add in the 1/N for the base_cost
+            weight = 0.1 + (0.1 * idx)
+            weight_dict = dict(weight=weight, hostname=hostname)
+            expected.append(weight_dict)
+
+        self.assertWeights(expected, num, request_spec, hosts)
diff --git a/nova/tests/test_scheduler.py b/nova/tests/scheduler/test_scheduler.py
index 54b3f80fb..50b6b52c6 100644
--- a/nova/tests/test_scheduler.py
+++ b/nova/tests/scheduler/test_scheduler.py
@@ -61,7 +61,8 @@ class SchedulerTestCase(test.TestCase):
     """Test case for scheduler"""
     def setUp(self):
         super(SchedulerTestCase, self).setUp()
-        self.flags(scheduler_driver='nova.tests.test_scheduler.TestDriver')
+        driver = 'nova.tests.scheduler.test_scheduler.TestDriver'
+        self.flags(scheduler_driver=driver)
 
     def _create_compute_service(self):
         """Create compute-manager(ComputeNode and Service record)."""
@@ -196,7 +197,7 @@ class ZoneSchedulerTestCase(test.TestCase):
         service.topic = 'compute'
         service.id = kwargs['id']
         service.availability_zone = kwargs['zone']
-        service.created_at = datetime.datetime.utcnow()
+        service.created_at = utils.utcnow()
         return service
 
     def test_with_two_zones(self):
@@ -290,7 +291,7 @@ class SimpleDriverTestCase(test.TestCase):
         dic['host'] = kwargs.get('host', 'dummy')
         s_ref = db.service_create(self.context, dic)
         if 'created_at' in kwargs.keys() or 'updated_at' in kwargs.keys():
-            t = datetime.datetime.utcnow() - datetime.timedelta(0)
+            t = utils.utcnow() - datetime.timedelta(0)
             dic['created_at'] = kwargs.get('created_at', t)
             dic['updated_at'] = kwargs.get('updated_at', t)
             db.service_update(self.context, s_ref['id'], dic)
@@ -401,7 +402,7 @@ class SimpleDriverTestCase(test.TestCase):
                                    FLAGS.compute_manager)
         compute1.start()
         s1 = db.service_get_by_args(self.context, 'host1', 'nova-compute')
-        now = datetime.datetime.utcnow()
+        now = utils.utcnow()
         delta = datetime.timedelta(seconds=FLAGS.service_down_time * 2)
         past = now - delta
         db.service_update(self.context, s1['id'], {'updated_at': past})
@@ -542,7 +543,7 @@ class SimpleDriverTestCase(test.TestCase):
     def test_wont_sechedule_if_specified_host_is_down(self):
         compute1 = self.start_service('compute', host='host1')
         s1 = db.service_get_by_args(self.context, 'host1', 'nova-compute')
-        now = datetime.datetime.utcnow()
+        now = utils.utcnow()
         delta = datetime.timedelta(seconds=FLAGS.service_down_time * 2)
         past = now - delta
         db.service_update(self.context, s1['id'], {'updated_at': past})
@@ -692,7 +693,7 @@ class SimpleDriverTestCase(test.TestCase):
         dic = {'instance_id': instance_id, 'size': 1}
         v_ref = db.volume_create(self.context, {'instance_id': instance_id,
                                                 'size': 1})
-        t1 = datetime.datetime.utcnow() - datetime.timedelta(1)
+        t1 = utils.utcnow() - datetime.timedelta(1)
         dic = {'created_at': t1, 'updated_at': t1, 'binary': 'nova-volume',
                'topic': 'volume', 'report_count': 0}
         s_ref = db.service_create(self.context, dic)
@@ -709,7 +710,7 @@ class SimpleDriverTestCase(test.TestCase):
         """Confirms src-compute node is alive."""
         instance_id = self._create_instance()
         i_ref = db.instance_get(self.context, instance_id)
-        t = datetime.datetime.utcnow() - datetime.timedelta(10)
+        t = utils.utcnow() - datetime.timedelta(10)
         s_ref = self._create_compute_service(created_at=t, updated_at=t,
                                              host=i_ref['host'])
 
@@ -737,7 +738,7 @@ class SimpleDriverTestCase(test.TestCase):
         """Confirms exception raises in case dest host does not exist."""
         instance_id = self._create_instance()
         i_ref = db.instance_get(self.context, instance_id)
-        t = datetime.datetime.utcnow() - datetime.timedelta(10)
+        t = utils.utcnow() - datetime.timedelta(10)
         s_ref = self._create_compute_service(created_at=t, updated_at=t,
                                              host=i_ref['host'])
 
@@ -796,7 +797,7 @@ class SimpleDriverTestCase(test.TestCase):
         # mocks for live_migration_common_check()
         instance_id = self._create_instance()
         i_ref = db.instance_get(self.context, instance_id)
-        t1 = datetime.datetime.utcnow() - datetime.timedelta(10)
+        t1 = utils.utcnow() - datetime.timedelta(10)
         s_ref = self._create_compute_service(created_at=t1, updated_at=t1,
                                              host=dest)
 
diff --git a/nova/tests/test_zone_aware_scheduler.py b/nova/tests/scheduler/test_zone_aware_scheduler.py
index 72b74be20..561fdea94 100644
--- a/nova/tests/test_zone_aware_scheduler.py
+++ b/nova/tests/scheduler/test_zone_aware_scheduler.py
@@ -22,6 +22,37 @@ from nova.scheduler import zone_aware_scheduler
 from nova.scheduler import zone_manager
 
 
+def _host_caps(multiplier):
+    # Returns host capabilities in the following way:
+    # host1 = memory:free 10 (100max)
+    #         disk:available 100 (1000max)
+    # hostN = memory:free 10 + 10N
+    #         disk:available 100 + 100N
+    # in other words: hostN has more resources than host0
+    # which means ... don't go above 10 hosts.
+    return {'host_name-description': 'XenServer %s' % multiplier,
+            'host_hostname': 'xs-%s' % multiplier,
+            'host_memory_total': 100,
+            'host_memory_overhead': 10,
+            'host_memory_free': 10 + multiplier * 10,
+            'host_memory_free-computed': 10 + multiplier * 10,
+            'host_other-config': {},
+            'host_ip_address': '192.168.1.%d' % (100 + multiplier),
+            'host_cpu_info': {},
+            'disk_available': 100 + multiplier * 100,
+            'disk_total': 1000,
+            'disk_used': 0,
+            'host_uuid': 'xxx-%d' % multiplier,
+            'host_name-label': 'xs-%s' % multiplier}
+
+
+def fake_zone_manager_service_states(num_hosts):
+    states = {}
+    for x in xrange(num_hosts):
+        states['host%02d' % (x + 1)] = {'compute': _host_caps(x)}
+    return states
+
+
 class FakeZoneAwareScheduler(zone_aware_scheduler.ZoneAwareScheduler):
     def filter_hosts(self, num, specs):
         # NOTE(sirp): this is returning [(hostname, services)]
diff --git a/nova/tests/test_auth.py b/nova/tests/test_auth.py
index f02dd94b7..7d00bddfe 100644
--- a/nova/tests/test_auth.py
+++ b/nova/tests/test_auth.py
@@ -86,6 +86,7 @@ class _AuthManagerBaseTestCase(test.TestCase):
         super(_AuthManagerBaseTestCase, self).setUp()
         self.flags(connection_type='fake')
         self.manager = manager.AuthManager(new=True)
+        self.manager.mc.cache = {}
 
     def test_create_and_find_user(self):
         with user_generator(self.manager):
diff --git a/nova/tests/test_compute.py b/nova/tests/test_compute.py
index 25454087d..b4ac2dbc4 100644
--- a/nova/tests/test_compute.py
+++ b/nova/tests/test_compute.py
@@ -19,7 +19,6 @@
 Tests For Compute
 """
 
-import datetime
 import mox
 import stubout
 
@@ -217,12 +216,12 @@ class ComputeTestCase(test.TestCase):
         instance_ref = db.instance_get(self.context, instance_id)
         self.assertEqual(instance_ref['launched_at'], None)
         self.assertEqual(instance_ref['deleted_at'], None)
-        launch = datetime.datetime.utcnow()
+        launch = utils.utcnow()
         self.compute.run_instance(self.context, instance_id)
         instance_ref = db.instance_get(self.context, instance_id)
         self.assert_(instance_ref['launched_at'] > launch)
         self.assertEqual(instance_ref['deleted_at'], None)
-        terminate = datetime.datetime.utcnow()
+        terminate = utils.utcnow()
         self.compute.terminate_instance(self.context, instance_id)
         self.context = self.context.elevated(True)
         instance_ref = db.instance_get(self.context, instance_id)
diff --git a/nova/tests/test_console.py b/nova/tests/test_console.py
index 1a9a867ee..831e7670f 100644
--- a/nova/tests/test_console.py
+++ b/nova/tests/test_console.py
@@ -20,8 +20,6 @@
 Tests For Console proxy.
 """
 
-import datetime
-
 from nova import context
 from nova import db
 from nova import exception
diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index 687964094..b6b36745a 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -724,6 +724,31 @@ class LibvirtConnTestCase(test.TestCase):
         super(LibvirtConnTestCase, self).tearDown()
 
 
+class NWFilterFakes:
+    def __init__(self):
+        self.filters = {}
+
+    def nwfilterLookupByName(self, name):
+        if name in self.filters:
+            return self.filters[name]
+        raise libvirt.libvirtError('Filter Not Found')
+
+    def filterDefineXMLMock(self, xml):
+        class FakeNWFilterInternal:
+            def __init__(self, parent, name):
+                self.name = name
+                self.parent = parent
+
+            def undefine(self):
+                del self.parent.filters[self.name]
+                pass
+        tree = xml_to_tree(xml)
+        name = tree.get('name')
+        if name not in self.filters:
+            self.filters[name] = FakeNWFilterInternal(self, name)
+        return True
+
+
 class IptablesFirewallTestCase(test.TestCase):
     def setUp(self):
         super(IptablesFirewallTestCase, self).setUp()
@@ -741,6 +766,20 @@ class IptablesFirewallTestCase(test.TestCase):
         self.fw = firewall.IptablesFirewallDriver(
                       get_connection=lambda: self.fake_libvirt_connection)
 
+    def lazy_load_library_exists(self):
+        """check if libvirt is available."""
+        # try to connect libvirt. if fail, skip test.
+        try:
+            import libvirt
+            import libxml2
+        except ImportError:
+            return False
+        global libvirt
+        libvirt = __import__('libvirt')
+        connection.libvirt = __import__('libvirt')
+        connection.libxml2 = __import__('libxml2')
+        return True
+
     def tearDown(self):
         self.manager.delete_project(self.project)
         self.manager.delete_user(self.user)
@@ -946,6 +985,40 @@ class IptablesFirewallTestCase(test.TestCase):
         self.mox.ReplayAll()
         self.fw.do_refresh_security_group_rules("fake")
 
+    def test_unfilter_instance_undefines_nwfilter(self):
+        # Skip if non-libvirt environment
+        if not self.lazy_load_library_exists():
+            return
+
+        admin_ctxt = context.get_admin_context()
+
+        fakefilter = NWFilterFakes()
+        self.fw.nwfilter._conn.nwfilterDefineXML =\
+                               fakefilter.filterDefineXMLMock
+        self.fw.nwfilter._conn.nwfilterLookupByName =\
+                               fakefilter.nwfilterLookupByName
+
+        instance_ref = self._create_instance_ref()
+        inst_id = instance_ref['id']
+        instance = db.instance_get(self.context, inst_id)
+
+        ip = '10.11.12.13'
+        network_ref = db.project_get_network(self.context, 'fake')
+        fixed_ip = {'address': ip, 'network_id': network_ref['id']}
+        db.fixed_ip_create(admin_ctxt, fixed_ip)
+        db.fixed_ip_update(admin_ctxt, ip, {'allocated': True,
+                                            'instance_id': inst_id})
+        self.fw.setup_basic_filtering(instance)
+        self.fw.prepare_instance_filter(instance)
+        self.fw.apply_instance_filter(instance)
+        original_filter_count = len(fakefilter.filters)
+        self.fw.unfilter_instance(instance)
+
+        # should undefine just the instance filter
+        self.assertEqual(original_filter_count - len(fakefilter.filters), 1)
+
+        db.instance_destroy(admin_ctxt, instance_ref['id'])
+
 
 class NWFilterTestCase(test.TestCase):
     def setUp(self):
@@ -1122,3 +1195,37 @@ class NWFilterTestCase(test.TestCase):
                                                  network_info,
                                                  "fake")
         self.assertEquals(len(result), 3)
+
+    def test_unfilter_instance_undefines_nwfilters(self):
+        admin_ctxt = context.get_admin_context()
+
+        fakefilter = NWFilterFakes()
+        self.fw._conn.nwfilterDefineXML = fakefilter.filterDefineXMLMock
+        self.fw._conn.nwfilterLookupByName = fakefilter.nwfilterLookupByName
+
+        instance_ref = self._create_instance()
+        inst_id = instance_ref['id']
+
+        self.security_group = self.setup_and_return_security_group()
+
+        db.instance_add_security_group(self.context, inst_id,
+                                       self.security_group.id)
+
+        instance = db.instance_get(self.context, inst_id)
+
+        ip = '10.11.12.13'
+        network_ref = db.project_get_network(self.context, 'fake')
+        fixed_ip = {'address': ip, 'network_id': network_ref['id']}
+        db.fixed_ip_create(admin_ctxt, fixed_ip)
+        db.fixed_ip_update(admin_ctxt, ip, {'allocated': True,
+                                            'instance_id': inst_id})
+        self.fw.setup_basic_filtering(instance)
+        self.fw.prepare_instance_filter(instance)
+        self.fw.apply_instance_filter(instance)
+        original_filter_count = len(fakefilter.filters)
+        self.fw.unfilter_instance(instance)
+
+        # should undefine 2 filters: instance and instance-secgroup
+        self.assertEqual(original_filter_count - len(fakefilter.filters), 2)
+
+        db.instance_destroy(admin_ctxt, instance_ref['id'])
diff --git a/nova/tests/test_middleware.py b/nova/tests/test_middleware.py
index 6564a6955..40d117c45 100644
--- a/nova/tests/test_middleware.py
+++ b/nova/tests/test_middleware.py
@@ -16,7 +16,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import datetime
 import webob
 import webob.dec
 import webob.exc