From c7a5e49664ab0bd18a57336e282fa6c3b9a17ca0 Mon Sep 17 00:00:00 2001 From: Brendan Abolivier Date: Tue, 26 Oct 2021 15:17:36 +0200 Subject: [PATCH] Implement an `on_new_event` callback (#11126) Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com> --- changelog.d/11126.feature | 1 + docs/modules/third_party_rules_callbacks.md | 21 +++++ synapse/events/third_party_rules.py | 31 +++++++ synapse/handlers/federation_event.py | 2 +- synapse/handlers/message.py | 9 +- synapse/notifier.py | 17 +++- synapse/replication/tcp/client.py | 3 +- tests/rest/client/test_third_party_rules.py | 93 ++++++++++++++++++++- 8 files changed, 165 insertions(+), 12 deletions(-) create mode 100644 changelog.d/11126.feature diff --git a/changelog.d/11126.feature b/changelog.d/11126.feature new file mode 100644 index 0000000000..c6078fe081 --- /dev/null +++ b/changelog.d/11126.feature @@ -0,0 +1 @@ +Add an `on_new_event` third-party rules callback to allow Synapse modules to act after an event has been sent into a room. diff --git a/docs/modules/third_party_rules_callbacks.md b/docs/modules/third_party_rules_callbacks.md index 034923da0f..a16e272f79 100644 --- a/docs/modules/third_party_rules_callbacks.md +++ b/docs/modules/third_party_rules_callbacks.md @@ -119,6 +119,27 @@ callback returns `True`, Synapse falls through to the next one. The value of the callback that does not return `True` will be used. If this happens, Synapse will not call any of the subsequent implementations of this callback. +### `on_new_event` + +_First introduced in Synapse v1.47.0_ + +```python +async def on_new_event( + event: "synapse.events.EventBase", + state_events: "synapse.types.StateMap", +) -> None: +``` + +Called after sending an event into a room. The module is passed the event, as well +as the state of the room _after_ the event. This means that if the event is a state event, +it will be included in this state. + +Note that this callback is called when the event has already been processed and stored +into the room, which means this callback cannot be used to deny persisting the event. To +deny an incoming event, see [`check_event_for_spam`](spam_checker_callbacks.md#check_event_for_spam) instead. + +If multiple modules implement this callback, Synapse runs them all in order. + ## Example The example below is a module that implements the third-party rules callback diff --git a/synapse/events/third_party_rules.py b/synapse/events/third_party_rules.py index 2a6dabdab6..8816ef4b76 100644 --- a/synapse/events/third_party_rules.py +++ b/synapse/events/third_party_rules.py @@ -36,6 +36,7 @@ CHECK_THREEPID_CAN_BE_INVITED_CALLBACK = Callable[ CHECK_VISIBILITY_CAN_BE_MODIFIED_CALLBACK = Callable[ [str, StateMap[EventBase], str], Awaitable[bool] ] +ON_NEW_EVENT_CALLBACK = Callable[[EventBase, StateMap[EventBase]], Awaitable] def load_legacy_third_party_event_rules(hs: "HomeServer") -> None: @@ -152,6 +153,7 @@ class ThirdPartyEventRules: self._check_visibility_can_be_modified_callbacks: List[ CHECK_VISIBILITY_CAN_BE_MODIFIED_CALLBACK ] = [] + self._on_new_event_callbacks: List[ON_NEW_EVENT_CALLBACK] = [] def register_third_party_rules_callbacks( self, @@ -163,6 +165,7 @@ class ThirdPartyEventRules: check_visibility_can_be_modified: Optional[ CHECK_VISIBILITY_CAN_BE_MODIFIED_CALLBACK ] = None, + on_new_event: Optional[ON_NEW_EVENT_CALLBACK] = None, ) -> None: """Register callbacks from modules for each hook.""" if check_event_allowed is not None: @@ -181,6 +184,9 @@ class ThirdPartyEventRules: check_visibility_can_be_modified, ) + if on_new_event is not None: + self._on_new_event_callbacks.append(on_new_event) + async def check_event_allowed( self, event: EventBase, context: EventContext ) -> Tuple[bool, Optional[dict]]: @@ -321,6 +327,31 @@ class ThirdPartyEventRules: return True + async def on_new_event(self, event_id: str) -> None: + """Let modules act on events after they've been sent (e.g. auto-accepting + invites, etc.) + + Args: + event_id: The ID of the event. + + Raises: + ModuleFailureError if a callback raised any exception. + """ + # Bail out early without hitting the store if we don't have any callbacks + if len(self._on_new_event_callbacks) == 0: + return + + event = await self.store.get_event(event_id) + state_events = await self._get_state_map_for_room(event.room_id) + + for callback in self._on_new_event_callbacks: + try: + await callback(event, state_events) + except Exception as e: + logger.exception( + "Failed to run module API callback %s: %s", callback, e + ) + async def _get_state_map_for_room(self, room_id: str) -> StateMap[EventBase]: """Given a room ID, return the state events of that room. diff --git a/synapse/handlers/federation_event.py b/synapse/handlers/federation_event.py index 9584d5bd46..bd1fa08cef 100644 --- a/synapse/handlers/federation_event.py +++ b/synapse/handlers/federation_event.py @@ -1916,7 +1916,7 @@ class FederationEventHandler: event_pos = PersistedEventPosition( self._instance_name, event.internal_metadata.stream_ordering ) - self._notifier.on_new_room_event( + await self._notifier.on_new_room_event( event, event_pos, max_stream_token, extra_users=extra_users ) diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index 2e024b551f..4a0fccfcc6 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -1537,13 +1537,16 @@ class EventCreationHandler: # If there's an expiry timestamp on the event, schedule its expiry. self._message_handler.maybe_schedule_expiry(event) - def _notify() -> None: + async def _notify() -> None: try: - self.notifier.on_new_room_event( + await self.notifier.on_new_room_event( event, event_pos, max_stream_token, extra_users=extra_users ) except Exception: - logger.exception("Error notifying about new room event") + logger.exception( + "Error notifying about new room event %s", + event.event_id, + ) run_in_background(_notify) diff --git a/synapse/notifier.py b/synapse/notifier.py index 1acd899fab..1882fffd2a 100644 --- a/synapse/notifier.py +++ b/synapse/notifier.py @@ -220,6 +220,8 @@ class Notifier: # down. self.remote_server_up_callbacks: List[Callable[[str], None]] = [] + self._third_party_rules = hs.get_third_party_event_rules() + self.clock = hs.get_clock() self.appservice_handler = hs.get_application_service_handler() self._pusher_pool = hs.get_pusherpool() @@ -267,7 +269,7 @@ class Notifier: """ self.replication_callbacks.append(cb) - def on_new_room_event( + async def on_new_room_event( self, event: EventBase, event_pos: PersistedEventPosition, @@ -275,9 +277,10 @@ class Notifier: extra_users: Optional[Collection[UserID]] = None, ): """Unwraps event and calls `on_new_room_event_args`.""" - self.on_new_room_event_args( + await self.on_new_room_event_args( event_pos=event_pos, room_id=event.room_id, + event_id=event.event_id, event_type=event.type, state_key=event.get("state_key"), membership=event.content.get("membership"), @@ -285,9 +288,10 @@ class Notifier: extra_users=extra_users or [], ) - def on_new_room_event_args( + async def on_new_room_event_args( self, room_id: str, + event_id: str, event_type: str, state_key: Optional[str], membership: Optional[str], @@ -302,7 +306,10 @@ class Notifier: listening to the room, and any listeners for the users in the `extra_users` param. - The events can be peristed out of order. The notifier will wait + This also notifies modules listening on new events via the + `on_new_event` callback. + + The events can be persisted out of order. The notifier will wait until all previous events have been persisted before notifying the client streams. """ @@ -318,6 +325,8 @@ class Notifier: ) self._notify_pending_new_room_events(max_room_stream_token) + await self._third_party_rules.on_new_event(event_id) + self.notify_replication() def _notify_pending_new_room_events(self, max_room_stream_token: RoomStreamToken): diff --git a/synapse/replication/tcp/client.py b/synapse/replication/tcp/client.py index 961c17762e..e29ae1e375 100644 --- a/synapse/replication/tcp/client.py +++ b/synapse/replication/tcp/client.py @@ -207,11 +207,12 @@ class ReplicationDataHandler: max_token = self.store.get_room_max_token() event_pos = PersistedEventPosition(instance_name, token) - self.notifier.on_new_room_event_args( + await self.notifier.on_new_room_event_args( event_pos=event_pos, max_room_stream_token=max_token, extra_users=extra_users, room_id=row.data.room_id, + event_id=row.data.event_id, event_type=row.data.type, state_key=row.data.state_key, membership=row.data.membership, diff --git a/tests/rest/client/test_third_party_rules.py b/tests/rest/client/test_third_party_rules.py index 531f09c48b..1c42c46630 100644 --- a/tests/rest/client/test_third_party_rules.py +++ b/tests/rest/client/test_third_party_rules.py @@ -15,7 +15,7 @@ import threading from typing import TYPE_CHECKING, Dict, Optional, Tuple from unittest.mock import Mock -from synapse.api.constants import EventTypes +from synapse.api.constants import EventTypes, Membership from synapse.api.errors import SynapseError from synapse.events import EventBase from synapse.events.third_party_rules import load_legacy_third_party_event_rules @@ -25,6 +25,7 @@ from synapse.types import JsonDict, Requester, StateMap from synapse.util.frozenutils import unfreeze from tests import unittest +from tests.test_utils import make_awaitable if TYPE_CHECKING: from synapse.module_api import ModuleApi @@ -74,7 +75,7 @@ class LegacyChangeEvents(LegacyThirdPartyRulesTestModule): return d -class ThirdPartyRulesTestCase(unittest.HomeserverTestCase): +class ThirdPartyRulesTestCase(unittest.FederatingHomeserverTestCase): servlets = [ admin.register_servlets, login.register_servlets, @@ -86,11 +87,29 @@ class ThirdPartyRulesTestCase(unittest.HomeserverTestCase): load_legacy_third_party_event_rules(hs) + # We're not going to be properly signing events as our remote homeserver is fake, + # therefore disable event signature checks. + # Note that these checks are not relevant to this test case. + + # Have this homeserver auto-approve all event signature checking. + async def approve_all_signature_checking(_, pdu): + return pdu + + hs.get_federation_server()._check_sigs_and_hash = approve_all_signature_checking + + # Have this homeserver skip event auth checks. This is necessary due to + # event auth checks ensuring that events were signed by the sender's homeserver. + async def _check_event_auth(origin, event, context, *args, **kwargs): + return context + + hs.get_federation_event_handler()._check_event_auth = _check_event_auth + return hs def prepare(self, reactor, clock, homeserver): - # Create a user and room to play with during the tests + # Create some users and a room to play with during the tests self.user_id = self.register_user("kermit", "monkey") + self.invitee = self.register_user("invitee", "hackme") self.tok = self.login("kermit", "monkey") # Some tests might prevent room creation on purpose. @@ -424,6 +443,74 @@ class ThirdPartyRulesTestCase(unittest.HomeserverTestCase): self.assertEqual(channel.code, 200) self.assertEqual(channel.json_body["i"], i) + def test_on_new_event(self): + """Test that the on_new_event callback is called on new events""" + on_new_event = Mock(make_awaitable(None)) + self.hs.get_third_party_event_rules()._on_new_event_callbacks.append( + on_new_event + ) + + # Send a message event to the room and check that the callback is called. + self.helper.send(room_id=self.room_id, tok=self.tok) + self.assertEqual(on_new_event.call_count, 1) + + # Check that the callback is also called on membership updates. + self.helper.invite( + room=self.room_id, + src=self.user_id, + targ=self.invitee, + tok=self.tok, + ) + + self.assertEqual(on_new_event.call_count, 2) + + args, _ = on_new_event.call_args + + self.assertEqual(args[0].membership, Membership.INVITE) + self.assertEqual(args[0].state_key, self.invitee) + + # Check that the invitee's membership is correct in the state that's passed down + # to the callback. + self.assertEqual( + args[1][(EventTypes.Member, self.invitee)].membership, + Membership.INVITE, + ) + + # Send an event over federation and check that the callback is also called. + self._send_event_over_federation() + self.assertEqual(on_new_event.call_count, 3) + + def _send_event_over_federation(self) -> None: + """Send a dummy event over federation and check that the request succeeds.""" + body = { + "origin": self.hs.config.server.server_name, + "origin_server_ts": self.clock.time_msec(), + "pdus": [ + { + "sender": self.user_id, + "type": EventTypes.Message, + "state_key": "", + "content": {"body": "hello world", "msgtype": "m.text"}, + "room_id": self.room_id, + "depth": 0, + "origin_server_ts": self.clock.time_msec(), + "prev_events": [], + "auth_events": [], + "signatures": {}, + "unsigned": {}, + } + ], + } + + channel = self.make_request( + method="PUT", + path="/_matrix/federation/v1/send/1", + content=body, + federation_auth_origin=self.hs.config.server.server_name.encode("utf8"), + ) + + self.assertEqual(channel.code, 200, channel.result) + def _update_power_levels(self, event_default: int = 0): """Updates the room's power levels.