Check unspecified flavor in user defined driver

In order to decide whether to process a router related
request, the user defined router flavor OVN driver needs to
check the flavor_id specified in the request. This change adds
the code to test the case when the API passed the flavor_id as
unspecified.

Change-Id: I4d7d9d5582b97246cad63ef7f5511b159d6c6791
Closes-Bug: #2059051
(cherry picked from commit 9d729bd)

Author: Miguel Lavalle

neutron/services/ovn_l3/service_providers/user_defined.py

@@ -16,6 +16,7 @@
 from neutron_lib.callbacks import events
 from neutron_lib.callbacks import registry
 from neutron_lib.callbacks import resources
+from neutron_lib import constants as const
 from neutron_lib.plugins import constants as plugin_constants
 from neutron_lib.plugins import directory
 from oslo_log import log as logging
@@ -44,7 +45,7 @@ def _flavor_plugin(self):
 
     def _is_user_defined_provider(self, context, router):
         flavor_id = router.get('flavor_id')
-        if flavor_id is None:
+        if flavor_id is None or flavor_id is const.ATTR_NOT_SPECIFIED:
             return False
         flavor = self._flavor_plugin.get_flavor(context, flavor_id)
         provider = self._flavor_plugin.get_flavor_next_provider(

neutron/tests/unit/services/ovn_l3/service_providers/test_user_defined.py

@@ -14,6 +14,7 @@
 from unittest import mock
 
 from neutron_lib.callbacks import events
+from neutron_lib import constants as const
 
 
 from neutron.db.models import l3
@@ -56,6 +57,14 @@ def test__is_user_defined_provider(self):
         self.assertFalse(self.provider._is_user_defined_provider(
             self.context, self.router))
 
+        # test flavor_id request not specified
+        self.router.flavor_id = None
+        self.assertFalse(self.provider._is_user_defined_provider(
+            self.context, self.router))
+        self.router.flavor_id = const.ATTR_NOT_SPECIFIED
+        self.assertFalse(self.provider._is_user_defined_provider(
+            self.context, self.router))
+
     def test_router_processing(self):
         with mock.patch.object(user_defined.LOG, 'debug') as log:
             payload = events.DBEventPayload(