migration: Add data migration of the users 'extern_type' attribute.

- Folow up from renaming the auth_container plugin.
- This migration renames the extern type for all users from 'container' to 'headers'

rhodecode/lib/dbmigrate/versions/054_version_4_1_0.py

@@ -0,0 +1,55 b''
+# -*- coding: utf-8 -*-
+
+import logging
+from collections import namedtuple
+
+from rhodecode.lib.dbmigrate.versions import _reset_base
+from rhodecode.model import init_model_encryption, meta
+
+log = logging.getLogger(__name__)
+
+
+def upgrade(migrate_engine):
+    """
+    Upgrade operations go here.
+    Don't create your own engine; bind migrate_engine to your metadata
+    """
+    _reset_base(migrate_engine)
+    from rhodecode.lib.dbmigrate.schema import db_3_7_0_0
+    init_model_encryption(db_3_7_0_0)
+    fixups(db_3_7_0_0, meta.Session)
+
+
+def downgrade(migrate_engine):
+    pass
+
+
+AUTH_PLUGINS_SETTING = "auth_plugins"
+
+EXTERN_TYPE_RENAME_MAP = {
+    'container': 'headers',
+}
+
+# Only used for logging purposes.
+RenameExternTypeOperation = namedtuple(
+    'RenameExternTypeOperation', ['user', 'old', 'new'])
+
+
+def fixups(models, Session):
+    operations = []
+
+    # Rename the extern_type attribute
+    query = models.User.query().filter(
+        models.User.extern_type.in_(EXTERN_TYPE_RENAME_MAP.keys()))
+    for user in query:
+        old = user.extern_type
+        new = EXTERN_TYPE_RENAME_MAP[old]
+        user.extern_type = new
+        Session.add(user)
+        operations.append(RenameExternTypeOperation(user, old, new))
+
+    log.info("Migration of users 'extern_type' attribute.")
+    for op in operations:
+        log.info("%s", op)
+
+    Session().commit()