DB_composed_op - optimize for empty n_add, l_add sets

1 files changed, 11 insertions, 10 deletions

diff --git a/src-py/db_controller.py b/src-py/db_controller.py
index bd085371..ddc25a85 100644
--- a/src-py/db_controller.py
+++ b/src-py/db_controller.py
@@ -125,28 +125,29 @@ class DB_composed_op(DB_op):
 
 class DBO_topo_diff_commit(DB_composed_op):
     """
-    commit a 
+    commit a Topo_Diff
     """
     def __init__(self, topo_diff):
         super(DBO_topo_diff_commit, self).__init__()
 
         # TODO rm link set
         # TODO rm node set
-        assert not topo_diff.node_set_rm, 'unsupported'
-        assert not topo_diff.link_set_rm, 'unsupported'
+        assert 0 == len(topo_diff.node_set_rm), 'unsupported'
+        assert 0 == len(topo_diff.link_set_rm), 'unsupported'
 
         n_add_map = db_util.meta_attr_list_to_meta_attr_map(topo_diff.node_set_add)
         l_add_map = db_util.meta_attr_list_to_meta_attr_map(topo_diff.link_set_add)
 
-        op_n_add = DBO_add_node_set(n_add_map)
-        op_l_add = DBO_add_link_set(l_add_map)
-        
+        #
         # [!] order critical
-        self.add_sub_op(op_n_add)
-        self.add_sub_op(op_l_add)
+        #
+        if len(n_add_map) > 0:
+            op_n_add = DBO_add_node_set(n_add_map)
+            self.add_sub_op(op_n_add)
 
-    def on_completion(self, data):
-        pass
+        if len(l_add_map) > 0:
+            op_l_add = DBO_add_link_set(l_add_map)
+            self.add_sub_op(op_l_add)
 
 class DBO_attr_diff_commit(DB_op):
     """