diff --git a/src/service/service/ServiceServiceServicerImpl.py b/src/service/service/ServiceServiceServicerImpl.py
index fe66c04e27dfe5023b2eaa5721adf0484c91e70f..cdb4f76604153fdc605b5cf18cbf43d6ba98571e 100644
--- a/src/service/service/ServiceServiceServicerImpl.py
+++ b/src/service/service/ServiceServiceServicerImpl.py
@@ -18,7 +18,8 @@ from common.method_wrappers.Decorator import MetricsPool, safe_and_metered_rpc_m
 from common.method_wrappers.ServiceExceptions import (
     AlreadyExistsException, InvalidArgumentException, NotFoundException, NotImplementedException,
     OperationFailedException)
-from common.proto.context_pb2 import Connection, Empty, Service, ServiceId, ServiceStatusEnum, ServiceTypeEnum, ConstraintActionEnum
+from common.proto.context_pb2 import (
+    Connection, Empty, Service, ServiceId, ServiceStatusEnum, ServiceTypeEnum, ConstraintActionEnum)
 from common.proto.pathcomp_pb2 import PathCompRequest
 from common.proto.service_pb2_grpc import ServiceServiceServicer
 from common.tools.context_queries.Service import get_service_by_id
@@ -108,6 +109,10 @@ class ServiceServiceServicerImpl(ServiceServiceServicer):
 
         LOGGER.warning('[before] request={:s}'.format(grpc_message_to_json_string(request)))
         for constraint in request.service_constraints:
+            if constraint.action == ConstraintActionEnum.CONSTRAINTACTION_UNDEFINED:
+                # Field action is new; assume if not set, it means SET
+                constraint.action = ConstraintActionEnum.CONSTRAINTACTION_SET
+
             if constraint.action != ConstraintActionEnum.CONSTRAINTACTION_SET: continue
             if constraint.WhichOneof('constraint') != 'endpoint_location': continue
             if constraint.endpoint_location.HasField('endpoint_id'): continue