NSX|V3: Handle port-not-found during get_ports

Under stress, a port might be deleted while geting ports list.
This patch prevent this port from being at the results, or crashing
the api.

Change-Id: Ib6d298a7990556da73277f549580d9c04512518e

vmware_nsx/plugins/nsx_v3/plugin.py

@@ -3569,10 +3569,17 @@ class NsxV3Plugin(agentschedulers_db.AZDhcpAgentSchedulerDbMixin,
                     context, filters, fields, sorts,
                     limit, marker, page_reverse))
             # Add port extensions
-            for port in ports:
+            for port in ports[:]:
                 if 'id' in port:
+                    try:
                         port_model = self._get_port(context, port['id'])
                         resource_extend.apply_funcs('ports', port, port_model)
+                    except n_exc.PortNotFound:
+                        # Port might have been deleted by now
+                        LOG.debug("Port %s was deleted during the get_ports "
+                                  "process, and is being skipped", port['id'])
+                        ports.remove(port)
+                        continue
                 self._extend_get_port_dict_qos_and_binding(context, port)
                 self._remove_provider_security_groups_from_list(port)
         return (ports if not fields else

vmware_nsx/tests/unit/nsx_v3/test_plugin.py

@@ -1250,6 +1250,28 @@ class TestPortsV2(test_plugin.TestPortsV2, NsxV3PluginTestCaseMixin,
             self._get_ports_with_fields(tenid, 'mac_address', 4)
             self._get_ports_with_fields(tenid, 'network_id', 4)
 
+    def test_list_ports_while_deleting(self):
+        self.plugin = directory.get_plugin()
+        orig_get_port = self.plugin._get_port
+
+        class local(object):
+            counter = 0
+
+        def mock_get_port(*args):
+            #global counter
+            local.counter += 1
+            if local.counter == 3:
+                raise n_exc.PortNotFound(port_id=args[1])
+            return orig_get_port(*args)
+
+        self.plugin = directory.get_plugin()
+        with self.port(), self.port(), self.port(), self.port() as p:
+            tenid = p['port']['tenant_id']
+            # get all ports, while "deleting" one of them:
+            with mock.patch.object(self.plugin, "_get_port",
+                                   side_effect=mock_get_port):
+                self._get_ports_with_fields(tenid, None, 3)
+
     def test_list_ports_filtered_by_security_groups(self):
         ctx = context.get_admin_context()
         with self.port() as port1, self.port() as port2: