Add another test mech driver for scale simulation

This driver immediately sets ports to ACTIVE upon being bound
to simulate OVS/LinuxBridge agent operation when utilizing
the fake.FakeDriver compute driver.

Change-Id: Ia0c89aa00c1998fdf64a81113c1a355f44719fa1

networking_arista/tests/unit/ml2/mechanism_ha_simulator.py

@@ -16,6 +16,14 @@
 from multiprocessing import Queue
 import random
 
+from neutron.agent import rpc as agent_rpc
+from neutron_lib.agent import topics
+from neutron_lib.api.definitions import portbindings
+from neutron_lib.callbacks import events
+from neutron_lib.callbacks import registry
+from neutron_lib.callbacks import resources
+from neutron_lib import context
+
 from networking_arista.ml2 import arista_sync
 from networking_arista.ml2.mechanism_arista import AristaDriver
 
@@ -58,3 +66,34 @@ class AristaHASimulationDriver(AristaDriver):
     def delete_port_postcommit(self, context):
         self.provision_queue = random.choice(self.provision_queues)
         super(AristaHASimulationDriver, self).delete_port_postcommit(context)
+
+
+class AristaHAScaleSimulationDriver(AristaHASimulationDriver):
+
+    def __init__(self):
+        super(AristaHAScaleSimulationDriver, self).__init__()
+        self.context = None
+        self.plugin_rpc = None
+
+    def initialize(self):
+        super(AristaHAScaleSimulationDriver, self).initialize()
+        self.context = context.get_admin_context_without_session()
+        # Subscribe to port updates to force ports to active after binding
+        # since a fake virt driver is being used, so OVS will never see
+        # the libvirt interfaces come up, triggering the OVS provisioning
+        self.plugin_rpc = agent_rpc.PluginApi(topics.PLUGIN)
+        registry.subscribe(self._port_update_callback,
+                           resources.PORT, events.AFTER_UPDATE)
+
+    def _port_update_callback(self, resource, event, trigger, **kwargs):
+        port = kwargs.get('port')
+        host = port.get(portbindings.HOST_ID)
+        vif_type = port.get(portbindings.VIF_TYPE)
+        device_dict = {'device': port['id'],
+                       'agent_id': 'ovs-agent-%s' % host,
+                       'host': host}
+        if vif_type == 'ovs':
+            self.plugin_rpc.update_device_up(self.context, **device_dict)
+        elif (port.get(portbindings.VNIC_TYPE) == 'normal'
+              and vif_type == 'unbound'):
+            self.plugin_rpc.update_device_down(self.context, **device_dict)

setup.cfg

@@ -35,6 +35,7 @@ neutron.ml2.mechanism_drivers =
     arista_ml2 = networking_arista.ml2.mechanism_arista:AristaDriver
     arista_test_fabric = networking_arista.tests.unit.ml2.mechanism_fabric:TestFabricDriver
     arista_ha_sim = networking_arista.tests.unit.ml2.mechanism_ha_simulator:AristaHASimulationDriver
+    arista_ha_scale_sim = networking_arista.tests.unit.ml2.mechanism_ha_simulator:AristaHAScaleSimulationDriver
 neutron.service_plugins =
     arista_l3 = networking_arista.l3Plugin.l3_arista:AristaL3ServicePlugin
     arista_security_group = networking_arista.ml2.security_groups.arista_security_groups:AristaSecurityGroupHandler