close db session per change

oml/changelog.py

@@ -65,6 +65,7 @@ class Changelog(db.Model):
     def apply_changes(cls, user, changes):
         trigger = changes
         for change in changes:
+            with db.session():
                 if not cls.apply_change(user, change, trigger=False):
                     logger.debug('FAIL %s', change)
                     trigger = False

oml/nodes.py

@@ -297,7 +297,6 @@ class Node(Thread):
             return False
         if not changes:
             return False
-        with db.session():
         r = Changelog.apply_changes(self.user, changes)
         return r