configurable port option for l2gw agent

whenever l2gw agent IP:PORT is configured in manager table
of ovsdb server, it has to be configured in l2gateway_agent.ini
so that l2gw agent can listen for the connection request from ovsdb
server for the configured port.

Change-Id: Iac81c41cbac7daf43e72c12f094d6fefe33ce749
Closes-Bug: 1580869

etc/l2gateway_agent.ini

@@ -11,10 +11,17 @@
 # ovsdb_hosts =
 # Example: ovsdb_hosts = 'ovsdb1:16.95.16.1:6632,ovsdb2:16.95.16.2:6632'
 
-#enable_manager = False
-#connection can be initiated by the ovsdb server.
-#By default 'enable_manager' value is False, turn on the variable to True
-#to initiate the connection from ovsdb server to l2gw agent.
+# enable_manager = False
+# (BoolOpt) connection can be initiated by the ovsdb server.
+# By default 'enable_manager' value is False, turn on the variable to True
+# to initiate the connection from ovsdb server to l2gw agent.
+# manager_table_listening_port = 6632
+# (PortOpt) set port number for l2gateway agent, so that it can listen
+# for ovsdb server,whenever its IP is entered in manager table of ovsdb server.
+# by default it is set to port 6632.
+# you can use vtep-ctl utility to populate manager table of ovsdb.
+# For Example: sudo vtep-ctl set-manager tcp:x.x.x.x:6640,
+# where x.x.x.x is IP of l2gateway agent and 6640 is a port.
 
 # (StrOpt) Base path to private key file(s).
 # Agent will find key file named

networking_l2gw/services/l2gateway/agent/ovsdb/base_connection.py

@@ -44,6 +44,8 @@ class BaseConnection(object):
         self.mgr = mgr
         self.enable_manager = cfg.CONF.ovsdb.enable_manager
         if self.enable_manager:
+            self.manager_table_listening_port = (
+                cfg.CONF.ovsdb.manager_table_listening_port)
             self.s = None
             self.check_c_sock = None
             self.check_sock_rcv = False
@@ -90,8 +92,9 @@ class BaseConnection(object):
     def _rcv_socket(self):
         # Create a socket object.
         self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        host = ''                  # Get local machine name
-        port = 6632                # Reserve a port for your service.
+        host = ''                        # Get local machine name
+        port = self.manager_table_listening_port
+        # configured port for your service.
         self.s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
         self.s.bind((host, port))        # Bind to the port
         self.s.listen(5)                 # Now wait for client connection.

networking_l2gw/services/l2gateway/common/config.py

@@ -36,6 +36,12 @@ OVSDB_OPTS = [
     cfg.BoolOpt('enable_manager',
                 default=False,
                 help=_('Set to True if ovsdb Manager manages the client')),
+    cfg.PortOpt('manager_table_listening_port',
+                default=6632,
+                help=_('Set port number for l2gw agent, so that it can '
+                       'listen to whenever its IP is entered in manager '
+                       'table of ovsdb server, For Ex: tcp:x.x.x.x:6640, '
+                       'where x.x.x.x is IP of l2gw agent')),
     cfg.IntOpt('max_connection_retries',
                default=10,
                help=_('Maximum number of retries to open a socket '

networking_l2gw/tests/unit/services/l2gateway/agent/ovsdb/test_base_connection.py

@@ -204,6 +204,8 @@ class TestBaseConnection_with_enable_manager(base.BaseTestCase):
             self.assertIsNone(self.l2gw_ovsdb_conn.check_c_sock)
             self.assertEqual(self.l2gw_ovsdb_conn.ovsdb_dicts, fake_dict)
             self.assertEqual(self.l2gw_ovsdb_conn.ovsdb_fd_states, fake_dict)
+            self.assertEqual(self.l2gw_ovsdb_conn.manager_table_listening_port,
+                             6632)
             self.assertTrue(mock_thread.called)
 
     def test_send_monitor_msg_to_ovsdb_connection(self):