Merge "Check a namespace existence by checking only its own directory" into stable/train

neutron/agent/linux/ip_lib.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import errno
+from os import path
 import re
 import threading
 import time
@@ -35,6 +36,7 @@ from neutron.agent.common import utils
 from neutron.common import ipv6_utils
 from neutron.common import utils as common_utils
 from neutron.privileged.agent.linux import ip_lib as privileged
+from neutron.privileged.agent.linux import utils as priv_utils
 
 LOG = logging.getLogger(__name__)
 
@@ -931,9 +933,16 @@ def network_namespace_exists(namespace, try_is_ready=False, **kwargs):
                          is ready to be operated.
     :param kwargs: Callers add any filters they use as kwargs
     """
+    if not namespace:
+        return False
+
     if not try_is_ready:
-        output = list_network_namespaces(**kwargs)
-        return namespace in output
+        nspath = kwargs.get('nspath') or netns.NETNS_RUN_DIR
+        nspath += '/' + namespace
+        if cfg.CONF.AGENT.use_helper_for_ns_read:
+            return priv_utils.path_exists(nspath)
+        else:
+            return path.exists(nspath)
 
     try:
         privileged.open_namespace(namespace)

neutron/privileged/agent/linux/utils.py

@@ -13,6 +13,7 @@
 #    under the License.
 
 import os
+from os import path
 import re
 
 from oslo_concurrency import processutils
@@ -45,5 +46,10 @@ def _find_listen_pids_namespace(namespace):
 
 
 @privileged.default.entrypoint
-def delete_if_exists(path, remove=os.unlink):
-    fileutils.delete_if_exists(path, remove=remove)
+def delete_if_exists(_path, remove=os.unlink):
+    fileutils.delete_if_exists(_path, remove=remove)
+
+
+@privileged.default.entrypoint
+def path_exists(_path):
+    return path.exists(_path)

neutron/tests/common/net_helpers.py

@@ -620,8 +620,8 @@ class VethFixture(fixtures.Fixture):
     def destroy(self):
         for port in self.ports:
             ip_wrapper = ip_lib.IPWrapper(port.namespace)
-            if (ip_wrapper.netns.exists(port.namespace) or
-                    port.namespace is None):
+            if (port.namespace is None or
+                    ip_wrapper.netns.exists(port.namespace)):
                 try:
                     ip_wrapper.del_veth(port.name)
                     break

neutron/tests/functional/agent/linux/test_ip_lib.py

@@ -660,10 +660,16 @@ class NamespaceTestCase(functional_base.BaseSudoTestCase):
         ip_lib.delete_network_namespace(self.namespace)
 
     def test_network_namespace_exists_ns_exists(self):
-        self.assertTrue(ip_lib.network_namespace_exists(self.namespace))
+        for use_helper_for_ns_read in (True, False):
+            cfg.CONF.set_override('use_helper_for_ns_read',
+                                  use_helper_for_ns_read, 'AGENT')
+            self.assertTrue(ip_lib.network_namespace_exists(self.namespace))
 
     def test_network_namespace_exists_ns_doesnt_exists(self):
-        self.assertFalse(ip_lib.network_namespace_exists('another_ns'))
+        for use_helper_for_ns_read in (True, False):
+            cfg.CONF.set_override('use_helper_for_ns_read',
+                                  use_helper_for_ns_read, 'AGENT')
+            self.assertFalse(ip_lib.network_namespace_exists('another_ns'))
 
     def test_network_namespace_exists_ns_exists_try_is_ready(self):
         self.assertTrue(ip_lib.network_namespace_exists(self.namespace,

neutron/tests/unit/agent/l3/test_agent.py

@@ -61,6 +61,7 @@ from neutron.conf.agent import common as agent_config
 from neutron.conf.agent.l3 import config as l3_config
 from neutron.conf.agent.l3 import ha as ha_conf
 from neutron.conf import common as base_config
+from neutron.privileged.agent.linux import utils as priv_utils
 from neutron.tests import base
 from neutron.tests.common import l3_test_common
 from neutron.tests.unit.agent.linux.test_utils import FakeUser
@@ -101,6 +102,8 @@ class BasicRouterOperationsFramework(base.BaseTestCase):
         self.list_network_namespaces_p = mock.patch(
             'neutron.agent.linux.ip_lib.list_network_namespaces')
         self.list_network_namespaces = self.list_network_namespaces_p.start()
+        self.path_exists_p = mock.patch.object(priv_utils, 'path_exists')
+        self.path_exists = self.path_exists_p.start()
 
         self.ensure_dir = mock.patch(
             'oslo_utils.fileutils.ensure_tree').start()

neutron/tests/unit/agent/linux/test_ip_lib.py

@@ -863,31 +863,6 @@ class TestIpNetnsCommand(TestIPCmdBase):
         self.netns_cmd.delete('ns')
         remove.assert_called_once_with('ns')
 
-    @mock.patch.object(pyroute2.netns, 'listnetns')
-    @mock.patch.object(priv_lib, 'list_netns')
-    def test_namespace_exists_use_helper(self, priv_listnetns, listnetns):
-        self.config(group='AGENT', use_helper_for_ns_read=True)
-        priv_listnetns.return_value = NETNS_SAMPLE
-        # need another instance to avoid mocking
-        netns_cmd = ip_lib.IpNetnsCommand(ip_lib.SubProcessBase())
-        self.assertTrue(
-            netns_cmd.exists('bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb'))
-        self.assertEqual(1, priv_listnetns.call_count)
-        self.assertFalse(listnetns.called)
-
-    @mock.patch.object(pyroute2.netns, 'listnetns')
-    @mock.patch.object(priv_lib, 'list_netns')
-    def test_namespace_does_not_exist_no_helper(self, priv_listnetns,
-                                                listnetns):
-        self.config(group='AGENT', use_helper_for_ns_read=False)
-        listnetns.return_value = NETNS_SAMPLE
-        # need another instance to avoid mocking
-        netns_cmd = ip_lib.IpNetnsCommand(ip_lib.SubProcessBase())
-        self.assertFalse(
-            netns_cmd.exists('bbbbbbbb-1111-2222-3333-bbbbbbbbbbbb'))
-        self.assertEqual(1, listnetns.call_count)
-        self.assertFalse(priv_listnetns.called)
-
     def test_execute(self):
         self.parent.namespace = 'ns'
         with mock.patch('neutron.agent.common.utils.execute') as execute: