From 54cd90ea60610a6dc24a291dd0cad4ce9bea8728 Mon Sep 17 00:00:00 2001
From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Date: Fri, 13 Jan 2023 19:32:10 +0000
Subject: [PATCH] Implement MSC3890: Remotely silence local notifications
 (#14775)

---
 changelog.d/14775.feature                         |  1 +
 .../complement/conf/workers-shared-extra.yaml.j2  |  2 ++
 scripts-dev/complement.sh                         |  2 +-
 synapse/config/experimental.py                    | 15 +++++++++++++++
 synapse/handlers/device.py                        | 11 ++++++++++-
 5 files changed, 29 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/14775.feature

diff --git a/changelog.d/14775.feature b/changelog.d/14775.feature
new file mode 100644
index 0000000000..7b7ee42cac
--- /dev/null
+++ b/changelog.d/14775.feature
@@ -0,0 +1 @@
+Implement support for MSC3890: Remotely silence local notifications.
\ No newline at end of file
diff --git a/docker/complement/conf/workers-shared-extra.yaml.j2 b/docker/complement/conf/workers-shared-extra.yaml.j2
index cb839fed07..1170694df5 100644
--- a/docker/complement/conf/workers-shared-extra.yaml.j2
+++ b/docker/complement/conf/workers-shared-extra.yaml.j2
@@ -102,6 +102,8 @@ experimental_features:
   {% endif %}
   # Filtering /messages by relation type.
   msc3874_enabled: true
+  # Enable deleting device-specific notification settings stored in account data
+  msc3890_enabled: true
   # Enable removing account data support
   msc3391_enabled: true
 
diff --git a/scripts-dev/complement.sh b/scripts-dev/complement.sh
index 51d1bac618..7c48d8bccb 100755
--- a/scripts-dev/complement.sh
+++ b/scripts-dev/complement.sh
@@ -190,7 +190,7 @@ fi
 
 extra_test_args=()
 
-test_tags="synapse_blacklist,msc3787,msc3874,msc3391"
+test_tags="synapse_blacklist,msc3787,msc3874,msc3890,msc3391"
 
 # All environment variables starting with PASS_ will be shared.
 # (The prefix is stripped off before reaching the container.)
diff --git a/synapse/config/experimental.py b/synapse/config/experimental.py
index a8b2db372d..72a17e0616 100644
--- a/synapse/config/experimental.py
+++ b/synapse/config/experimental.py
@@ -17,6 +17,7 @@ from typing import Any, Optional
 import attr
 
 from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersions
+from synapse.config import ConfigError
 from synapse.config._base import Config
 from synapse.types import JsonDict
 
@@ -93,6 +94,9 @@ class ExperimentalConfig(Config):
         # MSC2815 (allow room moderators to view redacted event content)
         self.msc2815_enabled: bool = experimental.get("msc2815_enabled", False)
 
+        # MSC3391: Removing account data.
+        self.msc3391_enabled = experimental.get("msc3391_enabled", False)
+
         # MSC3773: Thread notifications
         self.msc3773_enabled: bool = experimental.get("msc3773_enabled", False)
 
@@ -127,6 +131,17 @@ class ExperimentalConfig(Config):
             "msc3886_endpoint", None
         )
 
+        # MSC3890: Remotely silence local notifications
+        # Note: This option requires "experimental_features.msc3391_enabled" to be
+        # set to "true", in order to communicate account data deletions to clients.
+        self.msc3890_enabled: bool = experimental.get("msc3890_enabled", False)
+        if self.msc3890_enabled and not self.msc3391_enabled:
+            raise ConfigError(
+                "Option 'experimental_features.msc3391' must be set to 'true' to "
+                "enable 'experimental_features.msc3890'. MSC3391 functionality is "
+                "required to communicate account data deletions to clients."
+            )
+
         # MSC3912: Relation-based redactions.
         self.msc3912_enabled: bool = experimental.get("msc3912_enabled", False)
 
diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py
index 89864e1119..0640ea79a0 100644
--- a/synapse/handlers/device.py
+++ b/synapse/handlers/device.py
@@ -346,6 +346,7 @@ class DeviceHandler(DeviceWorkerHandler):
         super().__init__(hs)
 
         self.federation_sender = hs.get_federation_sender()
+        self._account_data_handler = hs.get_account_data_handler()
         self._storage_controllers = hs.get_storage_controllers()
 
         self.device_list_updater = DeviceListUpdater(hs, self)
@@ -502,7 +503,7 @@ class DeviceHandler(DeviceWorkerHandler):
             else:
                 raise
 
-        # Delete access tokens and e2e keys for each device. Not optimised as it is not
+        # Delete data specific to each device. Not optimised as it is not
         # considered as part of a critical path.
         for device_id in device_ids:
             await self._auth_handler.delete_access_tokens_for_user(
@@ -512,6 +513,14 @@ class DeviceHandler(DeviceWorkerHandler):
                 user_id=user_id, device_id=device_id
             )
 
+            if self.hs.config.experimental.msc3890_enabled:
+                # Remove any local notification settings for this device in accordance
+                # with MSC3890.
+                await self._account_data_handler.remove_account_data_for_user(
+                    user_id,
+                    f"org.matrix.msc3890.local_notification_settings.{device_id}",
+                )
+
         await self.notify_device_update(user_id, device_ids)
 
     async def update_device(self, user_id: str, device_id: str, content: dict) -> None: