Allow admins to require a manual approval process before new accounts can be used (using MSC3866) (#13556)

synapse/storage/schema/main/delta/73/03users_approved_column.sql

@@ -0,0 +1,20 @@
+/* Copyright 2022 The Matrix.org Foundation C.I.C
+ *
+ * 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.
+ */
+
+-- Add a column to the users table to track whether the user needs to be approved by an
+-- administrator.
+-- A NULL column means the user was created before this feature was supported by Synapse,
+-- and should be considered as TRUE.
+ALTER TABLE users ADD COLUMN approved BOOLEAN;