Fix NVP marking all routers as Error

DHC-1877

The NvpSynchronizer class in Neutron runs
a synchronization thread to sync nvp objects with
neutron objects. Since we don't use nvp's routers
the sync was failing making neutron showing all
the routers like if the were in Error state.
To fix this behaviour we override the two methods
responsible for the routers synchronization in the
NvpSynchronizer class to be a noop

Change-Id: I2d3a392d352474774824bc7cec579b2c9bbae472
Signed-off-by: Rosario Di Somma <rosario.disomma@dreamhost.com>

akanda/neutron/plugins/nvp_neutron_plugin.py

@@ -23,6 +23,7 @@ from neutron.db import l3_db
 from neutron.db import l3_rpc_base as l3_rpc
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import rpc
+from neutron.plugins.nicira.common import sync as nvp_sync
 from neutron.plugins.nicira.dhcp_meta import rpc as nvp_rpc
 from neutron.plugins.nicira.NeutronPlugin import nicira_db
 from neutron.plugins.nicira import NeutronPlugin as nvp
@@ -76,6 +77,23 @@ class AkandaNvpRpcCallbacks(l3_rpc.L3RpcCallbackMixin,
     pass
 
 
+class NvpSynchronizer(nvp_sync.NvpSynchronizer):
+    """
+    The NvpSynchronizer class in Neutron runs a synchronization thread to
+    sync nvp objects with neutron objects. Since we don't use nvp's routers
+    the sync was failing making neutron showing all the routers like if the
+    were in Error state. To fix this behaviour we override the two methods
+    responsible for the routers synchronization in the NvpSynchronizer class
+    to be a noop
+
+    """
+    def _synchronize_lrouters(self, *args, **kwargs):
+        pass
+
+    def synchronize_router(self, *args, **kwargs):
+        pass
+
+
 class NvpPluginV2(floatingip.ExplicitFloatingIPAllocationMixin,
                   nvp.NvpPluginV2):
     """
@@ -102,6 +120,13 @@ class NvpPluginV2(floatingip.ExplicitFloatingIPAllocationMixin,
             }
         }
 
+        self._synchronizer = NvpSynchronizer(
+            self, self.cluster,
+            self.nvp_sync_opts.state_sync_interval,
+            self.nvp_sync_opts.min_sync_req_delay,
+            self.nvp_sync_opts.min_chunk_size,
+            self.nvp_sync_opts.max_random_sync_delay)
+
     def setup_dhcpmeta_access(self):
         # Ok, so we're going to add L3 here too with the DHCP
         self.conn = rpc.create_connection(new=True)