diff --git a/__init__.py b/__init__.py
index f9df9af..62a98b8 100644
--- a/__init__.py
+++ b/__init__.py
@@ -10,6 +10,7 @@ from flask import request
 from flask import g
 from flask.ext.babel import Babel
 from flask.ext.principal import identity_loaded
+from flask.ext.principal import Principal
 
 import core
 from extensions import db
@@ -78,7 +79,7 @@ def configure_blueprints(app, modules):
 
 
 def configure_identity(app):
-
+    principal = Principal(app)
     @identity_loaded.connect_via(app)
     def on_identity_loaded(sender, identity):
         g.user = User.query.from_identity(identity)
diff --git a/core/attribute.py b/core/attribute.py
index edff09e..fd1aa54 100644
--- a/core/attribute.py
+++ b/core/attribute.py
@@ -104,7 +104,8 @@ def delete_attribute(attr_id=None):
 @attribute.route("/citype/<int:type_id>", methods=["GET"])
 def get_attributes_by_type(type_id=None):
     manager = CITypeAttributeManager()
-    from models.cmdb import CITypeCache, CIAttributeCache
+    from models.attribute import CIAttributeCache
+    from models.ci_type import CITypeCache
 
     t = CITypeCache.get(type_id)
     if not t:
diff --git a/lib/attribute.py b/lib/attribute.py
index 19e889d..dd6f6ca 100644
--- a/lib/attribute.py
+++ b/lib/attribute.py
@@ -152,6 +152,7 @@ class AttributeManager(object):
                 choice_table = type_map["choice"].get(attr.value_type)
                 db.session.query(choice_table).filter(
                     choice_table.attr_id == attr_id).delete()
+                db.session.flush()
             name = attr.attr_name
             CIAttributeCache.clean(attr)
             db.session.delete(attr)