From bfe6d5553abc5d812bce22488d9ea5137d2b9416 Mon Sep 17 00:00:00 2001
From: Brendan Abolivier <babolivier@matrix.org>
Date: Thu, 20 Jan 2022 19:19:40 +0100
Subject: [PATCH] Correctly await on_logged_out callbacks (#11786)

---
 changelog.d/11786.bugfix                  |  1 +
 synapse/handlers/auth.py                  |  2 +-
 tests/handlers/test_password_providers.py | 28 ++++++++++++++++++++++-
 3 files changed, 29 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/11786.bugfix

diff --git a/changelog.d/11786.bugfix b/changelog.d/11786.bugfix
new file mode 100644
index 0000000000..306875f2dd
--- /dev/null
+++ b/changelog.d/11786.bugfix
@@ -0,0 +1 @@
+Fix a bug introduced in Synapse 1.46.0 that prevented `on_logged_out` module callbacks from being correctly awaited by Synapse.
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index 2389c9ac52..bd1a322563 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -2281,7 +2281,7 @@ class PasswordAuthProvider:
         # call all of the on_logged_out callbacks
         for callback in self.on_logged_out_callbacks:
             try:
-                callback(user_id, device_id, access_token)
+                await callback(user_id, device_id, access_token)
             except Exception as e:
                 logger.warning("Failed to run module API callback %s: %s", callback, e)
                 continue
diff --git a/tests/handlers/test_password_providers.py b/tests/handlers/test_password_providers.py
index 08e9730d4d..2add72b28a 100644
--- a/tests/handlers/test_password_providers.py
+++ b/tests/handlers/test_password_providers.py
@@ -22,7 +22,7 @@ from twisted.internet import defer
 import synapse
 from synapse.handlers.auth import load_legacy_password_auth_providers
 from synapse.module_api import ModuleApi
-from synapse.rest.client import devices, login
+from synapse.rest.client import devices, login, logout
 from synapse.types import JsonDict
 
 from tests import unittest
@@ -155,6 +155,7 @@ class PasswordAuthProviderTests(unittest.HomeserverTestCase):
         synapse.rest.admin.register_servlets,
         login.register_servlets,
         devices.register_servlets,
+        logout.register_servlets,
     ]
 
     def setUp(self):
@@ -719,6 +720,31 @@ class PasswordAuthProviderTests(unittest.HomeserverTestCase):
         channel = self._send_password_login("localuser", "localpass")
         self.assertEqual(channel.code, 400, channel.result)
 
+    def test_on_logged_out(self):
+        """Tests that the on_logged_out callback is called when the user logs out."""
+        self.register_user("rin", "password")
+        tok = self.login("rin", "password")
+
+        self.called = False
+
+        async def on_logged_out(user_id, device_id, access_token):
+            self.called = True
+
+        on_logged_out = Mock(side_effect=on_logged_out)
+        self.hs.get_password_auth_provider().on_logged_out_callbacks.append(
+            on_logged_out
+        )
+
+        channel = self.make_request(
+            "POST",
+            "/_matrix/client/v3/logout",
+            {},
+            access_token=tok,
+        )
+        self.assertEqual(channel.code, 200)
+        on_logged_out.assert_called_once()
+        self.assertTrue(self.called)
+
     def _get_login_flows(self) -> JsonDict:
         channel = self.make_request("GET", "/_matrix/client/r0/login")
         self.assertEqual(channel.code, 200, channel.result)