Move deactivate_account into its own handler

Non-functional refactoring to move deactivate_account. This means that we'll be
able to properly deactivate devices and access tokens without introducing a
dependency loop.

synapse/handlers/deactivate_account.py

@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# 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 twisted.internet import defer
+
+from ._base import BaseHandler
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class DeactivateAccountHandler(BaseHandler):
+    """Handler which deals with deactivating user accounts."""
+    def __init__(self, hs):
+        super(DeactivateAccountHandler, self).__init__(hs)
+        self._auth_handler = hs.get_auth_handler()
+
+    @defer.inlineCallbacks
+    def deactivate_account(self, user_id):
+        """Deactivate a user's account
+
+        Args:
+            user_id (str): ID of user to be deactivated
+
+        Returns:
+            Deferred
+        """
+        # FIXME: Theoretically there is a race here wherein user resets
+        # password using threepid.
+        yield self._auth_handler.delete_access_tokens_for_user(user_id)
+        yield self.store.user_delete_threepids(user_id)
+        yield self.store.user_set_password_hash(user_id, None)