forked-synapse/synapse/handlers/receipts.py
Šimon Brandner ab18441573
Support stable identifiers for MSC2285: private read receipts. (#13273)
This adds support for the stable identifiers of MSC2285 while
continuing to support the unstable identifiers behind the configuration
flag. These will be removed in a future version.
2022-08-05 11:09:33 -04:00

322 lines
12 KiB
Python

# Copyright 2015, 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
from typing import TYPE_CHECKING, Iterable, List, Optional, Tuple
from synapse.api.constants import EduTypes, ReceiptTypes
from synapse.appservice import ApplicationService
from synapse.streams import EventSource
from synapse.types import (
JsonDict,
ReadReceipt,
StreamKeyType,
UserID,
get_domain_from_id,
)
if TYPE_CHECKING:
from synapse.server import HomeServer
logger = logging.getLogger(__name__)
class ReceiptsHandler:
def __init__(self, hs: "HomeServer"):
self.notifier = hs.get_notifier()
self.server_name = hs.config.server.server_name
self.store = hs.get_datastores().main
self.event_auth_handler = hs.get_event_auth_handler()
self.hs = hs
# We only need to poke the federation sender explicitly if its on the
# same instance. Other federation sender instances will get notified by
# `synapse.app.generic_worker.FederationSenderHandler` when it sees it
# in the receipts stream.
self.federation_sender = None
if hs.should_send_federation():
self.federation_sender = hs.get_federation_sender()
# If we can handle the receipt EDUs we do so, otherwise we route them
# to the appropriate worker.
if hs.get_instance_name() in hs.config.worker.writers.receipts:
hs.get_federation_registry().register_edu_handler(
EduTypes.RECEIPT, self._received_remote_receipt
)
else:
hs.get_federation_registry().register_instances_for_edu(
EduTypes.RECEIPT,
hs.config.worker.writers.receipts,
)
self.clock = self.hs.get_clock()
self.state = hs.get_state_handler()
async def _received_remote_receipt(self, origin: str, content: JsonDict) -> None:
"""Called when we receive an EDU of type m.receipt from a remote HS."""
receipts = []
for room_id, room_values in content.items():
# If we're not in the room just ditch the event entirely. This is
# probably an old server that has come back and thinks we're still in
# the room (or we've been rejoined to the room by a state reset).
is_in_room = await self.event_auth_handler.check_host_in_room(
room_id, self.server_name
)
if not is_in_room:
logger.info(
"Ignoring receipt for room %r from server %s as we're not in the room",
room_id,
origin,
)
continue
for receipt_type, users in room_values.items():
for user_id, user_values in users.items():
if get_domain_from_id(user_id) != origin:
logger.info(
"Received receipt for user %r from server %s, ignoring",
user_id,
origin,
)
continue
receipts.append(
ReadReceipt(
room_id=room_id,
receipt_type=receipt_type,
user_id=user_id,
event_ids=user_values["event_ids"],
data=user_values.get("data", {}),
)
)
await self._handle_new_receipts(receipts)
async def _handle_new_receipts(self, receipts: List[ReadReceipt]) -> bool:
"""Takes a list of receipts, stores them and informs the notifier."""
min_batch_id: Optional[int] = None
max_batch_id: Optional[int] = None
for receipt in receipts:
res = await self.store.insert_receipt(
receipt.room_id,
receipt.receipt_type,
receipt.user_id,
receipt.event_ids,
receipt.data,
)
if not res:
# res will be None if this receipt is 'old'
continue
stream_id, max_persisted_id = res
if min_batch_id is None or stream_id < min_batch_id:
min_batch_id = stream_id
if max_batch_id is None or max_persisted_id > max_batch_id:
max_batch_id = max_persisted_id
# Either both of these should be None or neither.
if min_batch_id is None or max_batch_id is None:
# no new receipts
return False
affected_room_ids = list({r.room_id for r in receipts})
self.notifier.on_new_event(
StreamKeyType.RECEIPT, max_batch_id, rooms=affected_room_ids
)
# Note that the min here shouldn't be relied upon to be accurate.
await self.hs.get_pusherpool().on_new_receipts(
min_batch_id, max_batch_id, affected_room_ids
)
return True
async def received_client_receipt(
self, room_id: str, receipt_type: str, user_id: str, event_id: str
) -> None:
"""Called when a client tells us a local user has read up to the given
event_id in the room.
"""
receipt = ReadReceipt(
room_id=room_id,
receipt_type=receipt_type,
user_id=user_id,
event_ids=[event_id],
data={"ts": int(self.clock.time_msec())},
)
is_new = await self._handle_new_receipts([receipt])
if not is_new:
return
if self.federation_sender and receipt_type not in (
ReceiptTypes.READ_PRIVATE,
ReceiptTypes.UNSTABLE_READ_PRIVATE,
):
await self.federation_sender.send_read_receipt(receipt)
class ReceiptEventSource(EventSource[int, JsonDict]):
def __init__(self, hs: "HomeServer"):
self.store = hs.get_datastores().main
self.config = hs.config
@staticmethod
def filter_out_private_receipts(
rooms: List[JsonDict], user_id: str
) -> List[JsonDict]:
"""
Filters a list of serialized receipts (as returned by /sync and /initialSync)
and removes private read receipts of other users.
This operates on the return value of get_linearized_receipts_for_rooms(),
which is wrapped in a cache. Care must be taken to ensure that the input
values are not modified.
Args:
rooms: A list of mappings, each mapping has a `content` field, which
is a map of event ID -> receipt type -> user ID -> receipt information.
Returns:
The same as rooms, but filtered.
"""
result = []
# Iterate through each room's receipt content.
for room in rooms:
# The receipt content with other user's private read receipts removed.
content = {}
# Iterate over each event ID / receipts for that event.
for event_id, orig_event_content in room.get("content", {}).items():
event_content = orig_event_content
# If there are private read receipts, additional logic is necessary.
if (
ReceiptTypes.READ_PRIVATE in event_content
or ReceiptTypes.UNSTABLE_READ_PRIVATE in event_content
):
# Make a copy without private read receipts to avoid leaking
# other user's private read receipts..
event_content = {
receipt_type: receipt_value
for receipt_type, receipt_value in event_content.items()
if receipt_type
not in (
ReceiptTypes.READ_PRIVATE,
ReceiptTypes.UNSTABLE_READ_PRIVATE,
)
}
# Copy the current user's private read receipt from the
# original content, if it exists.
user_private_read_receipt = orig_event_content.get(
ReceiptTypes.READ_PRIVATE, {}
).get(user_id, None)
if user_private_read_receipt:
event_content[ReceiptTypes.READ_PRIVATE] = {
user_id: user_private_read_receipt
}
user_unstable_private_read_receipt = orig_event_content.get(
ReceiptTypes.UNSTABLE_READ_PRIVATE, {}
).get(user_id, None)
if user_unstable_private_read_receipt:
event_content[ReceiptTypes.UNSTABLE_READ_PRIVATE] = {
user_id: user_unstable_private_read_receipt
}
# Include the event if there is at least one non-private read
# receipt or the current user has a private read receipt.
if event_content:
content[event_id] = event_content
# Include the event if there is at least one non-private read receipt
# or the current user has a private read receipt.
if content:
# Build a new event to avoid mutating the cache.
new_room = {k: v for k, v in room.items() if k != "content"}
new_room["content"] = content
result.append(new_room)
return result
async def get_new_events(
self,
user: UserID,
from_key: int,
limit: Optional[int],
room_ids: Iterable[str],
is_guest: bool,
explicit_room_id: Optional[str] = None,
) -> Tuple[List[JsonDict], int]:
from_key = int(from_key)
to_key = self.get_current_key()
if from_key == to_key:
return [], to_key
events = await self.store.get_linearized_receipts_for_rooms(
room_ids, from_key=from_key, to_key=to_key
)
events = ReceiptEventSource.filter_out_private_receipts(
events, user.to_string()
)
return events, to_key
async def get_new_events_as(
self, from_key: int, to_key: int, service: ApplicationService
) -> Tuple[List[JsonDict], int]:
"""Returns a set of new read receipt events that an appservice
may be interested in.
Args:
from_key: the stream position at which events should be fetched from
to_key: the stream position up to which events should be fetched to
service: The appservice which may be interested
Returns:
A two-tuple containing the following:
* A list of json dictionaries derived from read receipts that the
appservice may be interested in.
* The current read receipt stream token.
"""
from_key = int(from_key)
if from_key == to_key:
return [], to_key
# Fetch all read receipts for all rooms, up to a limit of 100. This is ordered
# by most recent.
rooms_to_events = await self.store.get_linearized_receipts_for_all_rooms(
from_key=from_key, to_key=to_key
)
# Then filter down to rooms that the AS can read
events = []
for room_id, event in rooms_to_events.items():
if not await service.is_interested_in_room(room_id, self.store):
continue
events.append(event)
return events, to_key
def get_current_key(self, direction: str = "f") -> int:
return self.store.get_max_receipt_stream_id()