mirror of
https://mau.dev/maunium/synapse.git
synced 2024-10-01 01:36:05 -04:00
241 lines
7.6 KiB
Python
241 lines
7.6 KiB
Python
# -*- coding: utf-8 -*-
|
|
# Copyright 2014 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.
|
|
|
|
|
|
from twisted.internet import defer
|
|
|
|
from synapse.util.logutils import log_function
|
|
from synapse.util.async import run_on_reactor
|
|
from synapse.api.events.room import RoomPowerLevelsEvent
|
|
|
|
from collections import namedtuple
|
|
|
|
import copy
|
|
import logging
|
|
import hashlib
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
def _get_state_key_from_event(event):
|
|
return event.state_key
|
|
|
|
|
|
KeyStateTuple = namedtuple("KeyStateTuple", ("context", "type", "state_key"))
|
|
|
|
|
|
class StateHandler(object):
|
|
""" Responsible for doing state conflict resolution.
|
|
"""
|
|
|
|
def __init__(self, hs):
|
|
self.store = hs.get_datastore()
|
|
|
|
@defer.inlineCallbacks
|
|
@log_function
|
|
def annotate_event_with_state(self, event, old_state=None):
|
|
""" Annotates the event with the current state events as of that event.
|
|
|
|
This method adds three new attributes to the event:
|
|
* `state_events`: The state up to and including the event. Encoded
|
|
as a dict mapping tuple (type, state_key) -> event.
|
|
* `old_state_events`: The state up to, but excluding, the event.
|
|
Encoded similarly as `state_events`.
|
|
* `state_group`: If there is an existing state group that can be
|
|
used, then return that. Otherwise return `None`. See state
|
|
storage for more information.
|
|
|
|
If the argument `old_state` is given (in the form of a list of
|
|
events), then they are used as a the values for `old_state_events` and
|
|
the value for `state_events` is generated from it. `state_group` is
|
|
set to None.
|
|
|
|
This needs to be called before persisting the event.
|
|
"""
|
|
yield run_on_reactor()
|
|
|
|
if old_state:
|
|
event.state_group = None
|
|
event.old_state_events = {
|
|
(s.type, s.state_key): s for s in old_state
|
|
}
|
|
event.state_events = event.old_state_events
|
|
|
|
if hasattr(event, "state_key"):
|
|
event.state_events[(event.type, event.state_key)] = event
|
|
|
|
defer.returnValue(False)
|
|
return
|
|
|
|
if hasattr(event, "outlier") and event.outlier:
|
|
event.state_group = None
|
|
event.old_state_events = None
|
|
event.state_events = {}
|
|
defer.returnValue(False)
|
|
return
|
|
|
|
ids = [e for e, _ in event.prev_events]
|
|
|
|
ret = yield self.resolve_state_groups(ids)
|
|
state_group, new_state = ret
|
|
|
|
event.old_state_events = copy.deepcopy(new_state)
|
|
|
|
if hasattr(event, "state_key"):
|
|
key = (event.type, event.state_key)
|
|
if key in new_state:
|
|
event.replaces_state = new_state[key].event_id
|
|
new_state[key] = event
|
|
elif state_group:
|
|
event.state_group = state_group
|
|
event.state_events = new_state
|
|
defer.returnValue(False)
|
|
|
|
event.state_group = None
|
|
event.state_events = new_state
|
|
|
|
defer.returnValue(hasattr(event, "state_key"))
|
|
|
|
@defer.inlineCallbacks
|
|
def get_current_state(self, room_id, event_type=None, state_key=""):
|
|
""" Returns the current state for the room as a list. This is done by
|
|
calling `get_latest_events_in_room` to get the leading edges of the
|
|
event graph and then resolving any of the state conflicts.
|
|
|
|
This is equivalent to getting the state of an event that were to send
|
|
next before receiving any new events.
|
|
|
|
If `event_type` is specified, then the method returns only the one
|
|
event (or None) with that `event_type` and `state_key`.
|
|
"""
|
|
events = yield self.store.get_latest_events_in_room(room_id)
|
|
|
|
event_ids = [
|
|
e_id
|
|
for e_id, _, _ in events
|
|
]
|
|
|
|
res = yield self.resolve_state_groups(event_ids)
|
|
|
|
if event_type:
|
|
defer.returnValue(res[1].get((event_type, state_key)))
|
|
return
|
|
|
|
defer.returnValue(res[1].values())
|
|
|
|
@defer.inlineCallbacks
|
|
@log_function
|
|
def resolve_state_groups(self, event_ids):
|
|
""" Given a list of event_ids this method fetches the state at each
|
|
event, resolves conflicts between them and returns them.
|
|
|
|
Return format is a tuple: (`state_group`, `state_events`), where the
|
|
first is the name of a state group if one and only one is involved,
|
|
otherwise `None`.
|
|
"""
|
|
state_groups = yield self.store.get_state_groups(
|
|
event_ids
|
|
)
|
|
|
|
group_names = set(state_groups.keys())
|
|
if len(group_names) == 1:
|
|
name, state_list = state_groups.items().pop()
|
|
state = {
|
|
(e.type, e.state_key): e
|
|
for e in state_list
|
|
}
|
|
defer.returnValue((name, state))
|
|
|
|
state = {}
|
|
for group, g_state in state_groups.items():
|
|
for s in g_state:
|
|
state.setdefault(
|
|
(s.type, s.state_key),
|
|
{}
|
|
)[s.event_id] = s
|
|
|
|
unconflicted_state = {
|
|
k: v.values()[0] for k, v in state.items()
|
|
if len(v.values()) == 1
|
|
}
|
|
|
|
conflicted_state = {
|
|
k: v.values()
|
|
for k, v in state.items()
|
|
if len(v.values()) > 1
|
|
}
|
|
|
|
try:
|
|
new_state = {}
|
|
new_state.update(unconflicted_state)
|
|
for key, events in conflicted_state.items():
|
|
new_state[key] = self._resolve_state_events(events)
|
|
except:
|
|
logger.exception("Failed to resolve state")
|
|
raise
|
|
|
|
defer.returnValue((None, new_state))
|
|
|
|
def _get_power_level_from_event_state(self, event, user_id):
|
|
if hasattr(event, "old_state_events") and event.old_state_events:
|
|
key = (RoomPowerLevelsEvent.TYPE, "", )
|
|
power_level_event = event.old_state_events.get(key)
|
|
level = None
|
|
if power_level_event:
|
|
level = power_level_event.content.get("users", {}).get(
|
|
user_id
|
|
)
|
|
if not level:
|
|
level = power_level_event.content.get("users_default", 0)
|
|
|
|
return level
|
|
else:
|
|
return 0
|
|
|
|
@log_function
|
|
def _resolve_state_events(self, events):
|
|
curr_events = events
|
|
|
|
new_powers = [
|
|
self._get_power_level_from_event_state(e, e.user_id)
|
|
for e in curr_events
|
|
]
|
|
|
|
new_powers = [
|
|
int(p) if p else 0 for p in new_powers
|
|
]
|
|
|
|
max_power = max(new_powers)
|
|
|
|
curr_events = [
|
|
z[0] for z in zip(curr_events, new_powers)
|
|
if z[1] == max_power
|
|
]
|
|
|
|
if not curr_events:
|
|
raise RuntimeError("Max didn't get a max?")
|
|
elif len(curr_events) == 1:
|
|
return curr_events[0]
|
|
|
|
# TODO: For now, just choose the one with the largest event_id.
|
|
return (
|
|
sorted(
|
|
curr_events,
|
|
key=lambda e: hashlib.sha1(
|
|
e.event_id + e.user_id + e.room_id + e.type
|
|
).hexdigest()
|
|
)[0]
|
|
)
|