Add support of a linuxbridge bridge in data-port config

When configuring data-port parameter with "ovs-bridge:linuxbridge"
a veth pair will be created to connect these two bridges. Name of
these virtual interfaces will be "veth-ovsbridge_name" and
"veth-linuxbridge_name".

Problem: When deploying neutron-openvswitch charm on a node contain
only one interface, we are not able to connect an ovs Bridge to
the physical interface because it is assigned to juju Bridge.

Change-Id: I5be72b9cc5948f5f791d522d1b46fd27e7303613
Closes-Bug:#1635067

config.yaml

@@ -68,6 +68,9 @@ options:
       bridge:mac for the same bridge so as to be able to configure multiple
       units. In this case the charm will run through the provided MAC addresses
       for each bridge until it finds one it can resolve to an interface name.
+      Port can also be a linuxbridge bridge. In this case a veth pair will be
+      created, the ovs bridge and the linuxbridge bridge will be connected. It
+      can be useful to connect the ovs bridge to juju bridge.
   disable-security-groups:
     type: boolean
     default: false

hooks/neutron_ovs_utils.py

@@ -43,6 +43,8 @@ import neutron_ovs_context
 from charmhelpers.contrib.network.ovs import (
     add_bridge,
     add_bridge_port,
+    is_linuxbridge_interface,
+    add_ovsbridge_linuxbridge,
     full_restart,
 )
 from charmhelpers.core.hookenv import (
@@ -410,7 +412,10 @@ def configure_ovs():
 
             for port, _br in portmaps.iteritems():
                 if _br == br:
-                    add_bridge_port(br, port, promisc=True)
+                    if not is_linuxbridge_interface(port):
+                        add_bridge_port(br, port, promisc=True)
+                    else:
+                        add_ovsbridge_linuxbridge(br, port)
     else:
         # NOTE: when in dpdk mode, add based on pci bus order
         #       with type 'dpdk'

unit_tests/test_neutron_ovs_utils.py

@@ -31,6 +31,8 @@ import charmhelpers.core.hookenv as hookenv
 TO_PATCH = [
     'add_bridge',
     'add_bridge_port',
+    'add_ovsbridge_linuxbridge',
+    'is_linuxbridge_interface',
     'dpdk_add_bridge_port',
     'apt_install',
     'apt_update',
@@ -322,6 +324,7 @@ class TestNeutronOVSUtils(CharmTestCase):
     @patch('charmhelpers.contrib.openstack.context.config')
     def test_configure_ovs_ovs_data_port(self, mock_config, _use_dvr):
         _use_dvr.return_value = False
+        self.is_linuxbridge_interface.return_value = False
         mock_config.side_effect = self.test_config.get
         self.config.side_effect = self.test_config.get
         self.ExternalPortContext.return_value = \
@@ -350,6 +353,24 @@ class TestNeutronOVSUtils(CharmTestCase):
         # Not called since we have a bogus bridge in data-ports
         self.assertFalse(self.add_bridge_port.called)
 
+    @patch.object(nutils, 'use_dvr')
+    @patch('charmhelpers.contrib.openstack.context.config')
+    def test_configure_ovs_data_port_with_bridge(self, mock_config, _use_dvr):
+        _use_dvr.return_value = False
+        self.is_linuxbridge_interface.return_value = True
+        mock_config.side_effect = self.test_config.get
+        self.config.side_effect = self.test_config.get
+        self.ExternalPortContext.return_value = \
+            DummyContext(return_value=None)
+
+        # Now test with bridge:bridge format
+        self.test_config.set('bridge-mappings', 'physnet1:br-foo')
+        self.test_config.set('data-port', 'br-foo:br-juju')
+        self.add_bridge.reset_mock()
+        self.add_bridge_port.reset_mock()
+        nutils.configure_ovs()
+        self.assertTrue(self.add_ovsbridge_linuxbridge.called)
+
     @patch.object(nutils, 'use_dvr')
     @patch('charmhelpers.contrib.openstack.context.config')
     def test_configure_ovs_starts_service_if_required(self, mock_config,