forked-synapse/synapse/handlers/typing.py
Erik Johnston 0c7f9cb81f
Don't unnecessarily start bg process while handling typing. (#8668)
There's no point starting a background process when all its going to do is bail if federation isn't enabled.
2020-10-27 15:32:19 +00:00

483 lines
17 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014-2016 OpenMarket 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.
import logging
import random
from collections import namedtuple
from typing import TYPE_CHECKING, List, Set, Tuple
from synapse.api.errors import AuthError, ShadowBanError, SynapseError
from synapse.appservice import ApplicationService
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.replication.tcp.streams import TypingStream
from synapse.types import JsonDict, UserID, get_domain_from_id
from synapse.util.caches.stream_change_cache import StreamChangeCache
from synapse.util.metrics import Measure
from synapse.util.wheel_timer import WheelTimer
if TYPE_CHECKING:
from synapse.server import HomeServer
logger = logging.getLogger(__name__)
# A tiny object useful for storing a user's membership in a room, as a mapping
# key
RoomMember = namedtuple("RoomMember", ("room_id", "user_id"))
# How often we expect remote servers to resend us presence.
FEDERATION_TIMEOUT = 60 * 1000
# How often to resend typing across federation.
FEDERATION_PING_INTERVAL = 40 * 1000
class FollowerTypingHandler:
"""A typing handler on a different process than the writer that is updated
via replication.
"""
def __init__(self, hs: "HomeServer"):
self.store = hs.get_datastore()
self.server_name = hs.config.server_name
self.clock = hs.get_clock()
self.is_mine_id = hs.is_mine_id
self.federation = None
if hs.should_send_federation():
self.federation = hs.get_federation_sender()
if hs.config.worker.writers.typing != hs.get_instance_name():
hs.get_federation_registry().register_instance_for_edu(
"m.typing", hs.config.worker.writers.typing,
)
# map room IDs to serial numbers
self._room_serials = {}
# map room IDs to sets of users currently typing
self._room_typing = {}
self._member_last_federation_poke = {}
self.wheel_timer = WheelTimer(bucket_size=5000)
self._latest_room_serial = 0
self.clock.looping_call(self._handle_timeouts, 5000)
def _reset(self):
"""Reset the typing handler's data caches.
"""
# map room IDs to serial numbers
self._room_serials = {}
# map room IDs to sets of users currently typing
self._room_typing = {}
self._member_last_federation_poke = {}
self.wheel_timer = WheelTimer(bucket_size=5000)
def _handle_timeouts(self):
logger.debug("Checking for typing timeouts")
now = self.clock.time_msec()
members = set(self.wheel_timer.fetch(now))
for member in members:
self._handle_timeout_for_member(now, member)
def _handle_timeout_for_member(self, now: int, member: RoomMember):
if not self.is_typing(member):
# Nothing to do if they're no longer typing
return
# Check if we need to resend a keep alive over federation for this
# user.
if self.federation and self.is_mine_id(member.user_id):
last_fed_poke = self._member_last_federation_poke.get(member, None)
if not last_fed_poke or last_fed_poke + FEDERATION_PING_INTERVAL <= now:
run_as_background_process(
"typing._push_remote", self._push_remote, member=member, typing=True
)
# Add a paranoia timer to ensure that we always have a timer for
# each person typing.
self.wheel_timer.insert(now=now, obj=member, then=now + 60 * 1000)
def is_typing(self, member):
return member.user_id in self._room_typing.get(member.room_id, [])
async def _push_remote(self, member, typing):
if not self.federation:
return
try:
users = await self.store.get_users_in_room(member.room_id)
self._member_last_federation_poke[member] = self.clock.time_msec()
now = self.clock.time_msec()
self.wheel_timer.insert(
now=now, obj=member, then=now + FEDERATION_PING_INTERVAL
)
for domain in {get_domain_from_id(u) for u in users}:
if domain != self.server_name:
logger.debug("sending typing update to %s", domain)
self.federation.build_and_send_edu(
destination=domain,
edu_type="m.typing",
content={
"room_id": member.room_id,
"user_id": member.user_id,
"typing": typing,
},
key=member,
)
except Exception:
logger.exception("Error pushing typing notif to remotes")
def process_replication_rows(
self, token: int, rows: List[TypingStream.TypingStreamRow]
):
"""Should be called whenever we receive updates for typing stream.
"""
if self._latest_room_serial > token:
# The master has gone backwards. To prevent inconsistent data, just
# clear everything.
self._reset()
# Set the latest serial token to whatever the server gave us.
self._latest_room_serial = token
for row in rows:
self._room_serials[row.room_id] = token
prev_typing = set(self._room_typing.get(row.room_id, []))
now_typing = set(row.user_ids)
self._room_typing[row.room_id] = row.user_ids
if self.federation:
run_as_background_process(
"_send_changes_in_typing_to_remotes",
self._send_changes_in_typing_to_remotes,
row.room_id,
prev_typing,
now_typing,
)
async def _send_changes_in_typing_to_remotes(
self, room_id: str, prev_typing: Set[str], now_typing: Set[str]
):
"""Process a change in typing of a room from replication, sending EDUs
for any local users.
"""
if not self.federation:
return
for user_id in now_typing - prev_typing:
if self.is_mine_id(user_id):
await self._push_remote(RoomMember(room_id, user_id), True)
for user_id in prev_typing - now_typing:
if self.is_mine_id(user_id):
await self._push_remote(RoomMember(room_id, user_id), False)
def get_current_token(self):
return self._latest_room_serial
class TypingWriterHandler(FollowerTypingHandler):
def __init__(self, hs):
super().__init__(hs)
assert hs.config.worker.writers.typing == hs.get_instance_name()
self.auth = hs.get_auth()
self.notifier = hs.get_notifier()
self.hs = hs
hs.get_federation_registry().register_edu_handler("m.typing", self._recv_edu)
hs.get_distributor().observe("user_left_room", self.user_left_room)
self._member_typing_until = {} # clock time we expect to stop
# caches which room_ids changed at which serials
self._typing_stream_change_cache = StreamChangeCache(
"TypingStreamChangeCache", self._latest_room_serial
)
def _handle_timeout_for_member(self, now: int, member: RoomMember):
super()._handle_timeout_for_member(now, member)
if not self.is_typing(member):
# Nothing to do if they're no longer typing
return
until = self._member_typing_until.get(member, None)
if not until or until <= now:
logger.info("Timing out typing for: %s", member.user_id)
self._stopped_typing(member)
return
async def started_typing(self, target_user, requester, room_id, timeout):
target_user_id = target_user.to_string()
auth_user_id = requester.user.to_string()
if not self.is_mine_id(target_user_id):
raise SynapseError(400, "User is not hosted on this homeserver")
if target_user_id != auth_user_id:
raise AuthError(400, "Cannot set another user's typing state")
if requester.shadow_banned:
# We randomly sleep a bit just to annoy the requester.
await self.clock.sleep(random.randint(1, 10))
raise ShadowBanError()
await self.auth.check_user_in_room(room_id, target_user_id)
logger.debug("%s has started typing in %s", target_user_id, room_id)
member = RoomMember(room_id=room_id, user_id=target_user_id)
was_present = member.user_id in self._room_typing.get(room_id, set())
now = self.clock.time_msec()
self._member_typing_until[member] = now + timeout
self.wheel_timer.insert(now=now, obj=member, then=now + timeout)
if was_present:
# No point sending another notification
return None
self._push_update(member=member, typing=True)
async def stopped_typing(self, target_user, requester, room_id):
target_user_id = target_user.to_string()
auth_user_id = requester.user.to_string()
if not self.is_mine_id(target_user_id):
raise SynapseError(400, "User is not hosted on this homeserver")
if target_user_id != auth_user_id:
raise AuthError(400, "Cannot set another user's typing state")
if requester.shadow_banned:
# We randomly sleep a bit just to annoy the requester.
await self.clock.sleep(random.randint(1, 10))
raise ShadowBanError()
await self.auth.check_user_in_room(room_id, target_user_id)
logger.debug("%s has stopped typing in %s", target_user_id, room_id)
member = RoomMember(room_id=room_id, user_id=target_user_id)
self._stopped_typing(member)
def user_left_room(self, user, room_id):
user_id = user.to_string()
if self.is_mine_id(user_id):
member = RoomMember(room_id=room_id, user_id=user_id)
self._stopped_typing(member)
def _stopped_typing(self, member):
if member.user_id not in self._room_typing.get(member.room_id, set()):
# No point
return None
self._member_typing_until.pop(member, None)
self._member_last_federation_poke.pop(member, None)
self._push_update(member=member, typing=False)
def _push_update(self, member, typing):
if self.hs.is_mine_id(member.user_id):
# Only send updates for changes to our own users.
run_as_background_process(
"typing._push_remote", self._push_remote, member, typing
)
self._push_update_local(member=member, typing=typing)
async def _recv_edu(self, origin, content):
room_id = content["room_id"]
user_id = content["user_id"]
member = RoomMember(user_id=user_id, room_id=room_id)
# Check that the string is a valid user id
user = UserID.from_string(user_id)
if user.domain != origin:
logger.info(
"Got typing update from %r with bad 'user_id': %r", origin, user_id
)
return
users = await self.store.get_users_in_room(room_id)
domains = {get_domain_from_id(u) for u in users}
if self.server_name in domains:
logger.info("Got typing update from %s: %r", user_id, content)
now = self.clock.time_msec()
self._member_typing_until[member] = now + FEDERATION_TIMEOUT
self.wheel_timer.insert(now=now, obj=member, then=now + FEDERATION_TIMEOUT)
self._push_update_local(member=member, typing=content["typing"])
def _push_update_local(self, member, typing):
room_set = self._room_typing.setdefault(member.room_id, set())
if typing:
room_set.add(member.user_id)
else:
room_set.discard(member.user_id)
self._latest_room_serial += 1
self._room_serials[member.room_id] = self._latest_room_serial
self._typing_stream_change_cache.entity_has_changed(
member.room_id, self._latest_room_serial
)
self.notifier.on_new_event(
"typing_key", self._latest_room_serial, rooms=[member.room_id]
)
async def get_all_typing_updates(
self, instance_name: str, last_id: int, current_id: int, limit: int
) -> Tuple[List[Tuple[int, list]], int, bool]:
"""Get updates for typing replication stream.
Args:
instance_name: The writer we want to fetch updates from. Unused
here since there is only ever one writer.
last_id: The token to fetch updates from. Exclusive.
current_id: The token to fetch updates up to. Inclusive.
limit: The requested limit for the number of rows to return. The
function may return more or fewer rows.
Returns:
A tuple consisting of: the updates, a token to use to fetch
subsequent updates, and whether we returned fewer rows than exists
between the requested tokens due to the limit.
The token returned can be used in a subsequent call to this
function to get further updates.
The updates are a list of 2-tuples of stream ID and the row data
"""
if last_id == current_id:
return [], current_id, False
changed_rooms = self._typing_stream_change_cache.get_all_entities_changed(
last_id
)
if changed_rooms is None:
changed_rooms = self._room_serials
rows = []
for room_id in changed_rooms:
serial = self._room_serials[room_id]
if last_id < serial <= current_id:
typing = self._room_typing[room_id]
rows.append((serial, [room_id, list(typing)]))
rows.sort()
limited = False
# We, unusually, use a strict limit here as we have all the rows in
# memory rather than pulling them out of the database with a `LIMIT ?`
# clause.
if len(rows) > limit:
rows = rows[:limit]
current_id = rows[-1][0]
limited = True
return rows, current_id, limited
def process_replication_rows(
self, token: int, rows: List[TypingStream.TypingStreamRow]
):
# The writing process should never get updates from replication.
raise Exception("Typing writer instance got typing info over replication")
class TypingNotificationEventSource:
def __init__(self, hs):
self.hs = hs
self.clock = hs.get_clock()
# We can't call get_typing_handler here because there's a cycle:
#
# Typing -> Notifier -> TypingNotificationEventSource -> Typing
#
self.get_typing_handler = hs.get_typing_handler
def _make_event_for(self, room_id):
typing = self.get_typing_handler()._room_typing[room_id]
return {
"type": "m.typing",
"room_id": room_id,
"content": {"user_ids": list(typing)},
}
async def get_new_events_as(
self, from_key: int, service: ApplicationService
) -> Tuple[List[JsonDict], int]:
"""Returns a set of new typing events that an appservice
may be interested in.
Args:
from_key: the stream position at which events should be fetched from
service: The appservice which may be interested
"""
with Measure(self.clock, "typing.get_new_events_as"):
from_key = int(from_key)
handler = self.get_typing_handler()
events = []
for room_id in handler._room_serials.keys():
if handler._room_serials[room_id] <= from_key:
continue
if not await service.matches_user_in_member_list(
room_id, handler.store
):
continue
events.append(self._make_event_for(room_id))
return (events, handler._latest_room_serial)
async def get_new_events(self, from_key, room_ids, **kwargs):
with Measure(self.clock, "typing.get_new_events"):
from_key = int(from_key)
handler = self.get_typing_handler()
events = []
for room_id in room_ids:
if room_id not in handler._room_serials:
continue
if handler._room_serials[room_id] <= from_key:
continue
events.append(self._make_event_for(room_id))
return (events, handler._latest_room_serial)
def get_current_key(self):
return self.get_typing_handler()._latest_room_serial