Merge "[OVN] Allow to execute ``MetadataProxyHandler`` in a local thread"

neutron/agent/ovn/metadata/agent.py

@@ -241,11 +241,6 @@ class MetadataAgent(object):
         self.ovs_idl = ovsdb.MetadataAgentOvsIdl().start()
         self._load_config()
 
-        # Launch the server that will act as a proxy between the VM's and Nova.
-        proxy = metadata_server.UnixDomainMetadataProxy(self.conf,
-                self.chassis)
-        proxy.run()
-
         tables = ('Encap', 'Port_Binding', 'Datapath_Binding', 'SB_Global',
                   'Chassis')
         events = (PortBindingChassisCreatedEvent(self),
@@ -271,13 +266,18 @@ class MetadataAgent(object):
         # Now IDL connections can be safely used.
         self._post_fork_event.set()
 
+        # Launch the server that will act as a proxy between the VM's and Nova.
+        self._proxy = metadata_server.UnixDomainMetadataProxy(
+            self.conf, self.chassis, sb_idl=self.sb_idl)
+        self._proxy.run()
+
         # Do the initial sync.
         self.sync()
 
         # Register the agent with its corresponding Chassis
         self.register_metadata_agent()
 
-        proxy.wait()
+        self._proxy.wait()
 
     @ovn_utils.retry()
     def register_metadata_agent(self):

neutron/agent/ovn/metadata/server.py

@@ -44,10 +44,10 @@ MODE_MAP = {
 
 class MetadataProxyHandler(object):
 
-    def __init__(self, conf, chassis):
+    def __init__(self, conf, chassis, sb_idl):
         self.conf = conf
         self.chassis = chassis
-        self._sb_idl = None
+        self._sb_idl = sb_idl
         self._post_fork_event = threading.Event()
         self.subscribe()
 
@@ -193,9 +193,10 @@ class MetadataProxyHandler(object):
 
 class UnixDomainMetadataProxy(object):
 
-    def __init__(self, conf, chassis):
+    def __init__(self, conf, chassis, sb_idl=None):
         self.conf = conf
         self.chassis = chassis
+        self.sb_idl = sb_idl
         agent_utils.ensure_directory_exists_without_file(
             cfg.CONF.metadata_proxy_socket)
 
@@ -224,7 +225,9 @@ class UnixDomainMetadataProxy(object):
         md_workers = self.conf.metadata_workers
         if md_workers is None:
             md_workers = 2
-        self.server.start(MetadataProxyHandler(self.conf, self.chassis),
+        sb_idl = self.sb_idl if md_workers == 0 else None
+        self.server.start(MetadataProxyHandler(self.conf, self.chassis,
+                                               sb_idl),
                           self.conf.metadata_proxy_socket,
                           workers=md_workers,
                           backlog=self.conf.metadata_backlog,

neutron/tests/functional/agent/ovn/metadata/test_metadata_agent.py

@@ -87,18 +87,17 @@ class TestMetadataAgent(base.TestOVNFunctionalBase):
 
         ovn_sb_db = self.ovsdb_server_mgr.get_ovsdb_connection_path('sb')
         conf.set_override('ovn_sb_connection', ovn_sb_db, group='ovn')
-
-        # We don't need the HA proxy server running for now
-        p = mock.patch.object(metadata_server, 'UnixDomainMetadataProxy')
-        p.start()
-        self.addCleanup(p.stop)
+        conf.set_override('metadata_workers', '0')
 
         self.chassis_name = self.add_fake_chassis(self.FAKE_CHASSIS_HOST)
         mock.patch.object(agent.MetadataAgent,
                           '_get_own_chassis_name',
                           return_value=self.chassis_name).start()
         agt = agent.MetadataAgent(conf)
-        agt.start()
+        with mock.patch.object(metadata_server.UnixDomainMetadataProxy,
+                               'wait'):
+            agt.start()
+
         # Metadata agent will open connections to OVS and SB databases.
         # Close connections to them when the test ends,
         self.addCleanup(agt.ovs_idl.ovsdb_connection.stop)
@@ -338,3 +337,9 @@ class TestMetadataAgent(base.TestOVNFunctionalBase):
         else:
             self.fail('Rule not found in "mangle" table, in namespace %s' %
                       namespace)
+
+    def test_metadata_proxy_handler_idl(self):
+        # This test relies on the configuration option metadata_workers=0
+        proxy_sb_idl = self.agent._proxy.server._server._application.sb_idl
+        agent_sb_idl = self.agent.sb_idl
+        self.assertEqual(agent_sb_idl, proxy_sb_idl)

neutron/tests/unit/agent/ovn/metadata/test_server.py

@@ -55,8 +55,8 @@ class TestMetadataProxyHandler(base.BaseTestCase):
         self.useFixture(self.fake_conf_fixture)
         self.log_p = mock.patch.object(agent, 'LOG')
         self.log = self.log_p.start()
-        self.handler = agent.MetadataProxyHandler(self.fake_conf, 'chassis1')
-        self.handler.sb_idl = mock.Mock()
+        self.handler = agent.MetadataProxyHandler(self.fake_conf, 'chassis1',
+                                                  mock.Mock())
         self.handler._post_fork_event.set()
 
     def test_call(self):