DB migration to fix now invalid User.names values that are already in DB.

Author: Kulv3r

migrations/MANUAL-fix-usernames-6b042b.py

@@ -0,0 +1,50 @@
+# Copyright 2016 Eugene Frolov <eugene@frolov.net.ru>
+#
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from restalchemy.storage.sql import migrations
+
+
+class MigrationStep(migrations.AbstarctMigrationStep):
+
+    def __init__(self):
+        self._depends = ["0023-nullable_fio-c9cb3a.py"]
+
+    @property
+    def migration_id(self):
+        return "6b042b1d-df57-4553-a031-8ae74ffab015"
+
+    @property
+    def is_manual(self):
+        return True
+
+    def upgrade(self, session):
+        expression = """
+            UPDATE iam_users
+            SET 
+                email = CASE 
+                            WHEN email IS NULL THEN name
+                            ELSE email
+                        END,
+                name = SUBSTRING(name, 1, POSITION('@' IN name) - 1)
+            WHERE name LIKE '%@%';
+        """
+        session.execute(expression)
+
+    def downgrade(self, session):
+        pass
+
+
+migration_step = MigrationStep()