forked-synapse/synapse/push/bulk_push_rule_evaluator.py
2017-05-19 11:44:11 +01:00

359 lines
13 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2015 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 twisted.internet import defer
from .push_rule_evaluator import PushRuleEvaluatorForEvent
from synapse.visibility import filter_events_for_clients_context
from synapse.api.constants import EventTypes, Membership
from synapse.util.caches.descriptors import cached
from synapse.util.async import Linearizer
from collections import namedtuple
logger = logging.getLogger(__name__)
rules_by_room = {}
class BulkPushRuleEvaluator(object):
"""Calculates the outcome of push rules for an event for all users in the
room at once.
"""
def __init__(self, hs):
self.hs = hs
self.store = hs.get_datastore()
@defer.inlineCallbacks
def _get_rules_for_event(self, event, context):
"""This gets the rules for all users in the room at the time of the event,
as well as the push rules for the invitee if the event is an invite.
Returns:
dict of user_id -> push_rules
"""
room_id = event.room_id
rules_for_room = self._get_rules_for_room(room_id)
rules_by_user = yield rules_for_room.get_rules(context)
# if this event is an invite event, we may need to run rules for the user
# who's been invited, otherwise they won't get told they've been invited
if event.type == 'm.room.member' and event.content['membership'] == 'invite':
invited = event.state_key
if invited and self.hs.is_mine_id(invited):
has_pusher = yield self.store.user_has_pusher(invited)
if has_pusher:
rules_by_user = dict(rules_by_user)
rules_by_user[invited] = yield self.store.get_push_rules_for_user(
invited
)
defer.returnValue(rules_by_user)
@cached()
def _get_rules_for_room(self, room_id):
"""Get the current RulesForRoom object for the given room id
Returns:
RulesForRoom
"""
# It's important that RulesForRoom gets added to self._get_rules_for_room.cache
# before any lookup methods get called on it as otherwise there may be
# a race if invalidate_all gets called (which assumes its in the cache)
return RulesForRoom(self.hs, room_id, self._get_rules_for_room.cache)
@defer.inlineCallbacks
def action_for_event_by_user(self, event, context):
"""Given an event and context, evaluate the push rules and return
the results
Returns:
dict of user_id -> action
"""
rules_by_user = yield self._get_rules_for_event(event, context)
actions_by_user = {}
# None of these users can be peeking since this list of users comes
# from the set of users in the room, so we know for sure they're all
# actually in the room.
user_tuples = [(u, False) for u in rules_by_user]
filtered_by_user = yield filter_events_for_clients_context(
self.store, user_tuples, [event], {event.event_id: context}
)
room_members = yield self.store.get_joined_users_from_context(
event, context
)
evaluator = PushRuleEvaluatorForEvent(event, len(room_members))
condition_cache = {}
for uid, rules in rules_by_user.iteritems():
display_name = None
profile_info = room_members.get(uid)
if profile_info:
display_name = profile_info.display_name
if not display_name:
# Handle the case where we are pushing a membership event to
# that user, as they might not be already joined.
if event.type == EventTypes.Member and event.state_key == uid:
display_name = event.content.get("displayname", None)
filtered = filtered_by_user[uid]
if len(filtered) == 0:
continue
if filtered[0].sender == uid:
continue
for rule in rules:
if 'enabled' in rule and not rule['enabled']:
continue
matches = _condition_checker(
evaluator, rule['conditions'], uid, display_name, condition_cache
)
if matches:
actions = [x for x in rule['actions'] if x != 'dont_notify']
if actions and 'notify' in actions:
actions_by_user[uid] = actions
break
defer.returnValue(actions_by_user)
def _condition_checker(evaluator, conditions, uid, display_name, cache):
for cond in conditions:
_id = cond.get("_id", None)
if _id:
res = cache.get(_id, None)
if res is False:
return False
elif res is True:
continue
res = evaluator.matches(cond, uid, display_name)
if _id:
cache[_id] = bool(res)
if not res:
return False
return True
class RulesForRoom(object):
"""Caches push rules for users in a room.
This efficiently handles users joining/leaving the room by not invalidating
the entire cache for the room.
"""
def __init__(self, hs, room_id, rules_for_room_cache):
"""
Args:
hs (HomeServer)
room_id (str)
rules_for_room_cache(Cache): The cache object that caches these
RoomsForUser objects.
"""
self.room_id = room_id
self.is_mine_id = hs.is_mine_id
self.store = hs.get_datastore()
self.linearizer = Linearizer(name="rules_for_room")
self.member_map = {} # event_id -> (user_id, state)
self.rules_by_user = {} # user_id -> rules
# The last state group we updated the caches for. If the state_group of
# a new event comes along, we know that we can just return the cached
# result.
# On invalidation of the rules themselves (if the user changes them),
# we invalidate everything and set state_group to `object()`
self.state_group = object()
# A sequence number to keep track of when we're allowed to update the
# cache. We bump the sequence number when we invalidate the cache. If
# the sequence number changes while we're calculating stuff we should
# not update the cache with it.
self.sequence = 0
# We need to be clever on the invalidating caches callbacks, as
# otherwise the invalidation callback holds a reference to the object,
# potentially causing it to leak.
# To get around this we pass a function that on invalidations looks ups
# the RoomsForUser entry in the cache, rather than keeping a reference
# to self around in the callback.
self.invalidate_all_cb = _Invalidation(rules_for_room_cache, room_id)
@defer.inlineCallbacks
def get_rules(self, context):
"""Given an event context return the rules for all users who are
currently in the room.
"""
state_group = context.state_group
with (yield self.linearizer.queue(())):
if state_group and self.state_group == state_group:
defer.returnValue(self.rules_by_user)
ret_rules_by_user = {}
missing_member_event_ids = {}
if state_group and self.state_group == context.prev_group:
# If we have a simple delta then we can reuse most of the previous
# results.
ret_rules_by_user = self.rules_by_user
current_state_ids = context.delta_ids
else:
current_state_ids = context.current_state_ids
# Loop through to see which member events we've seen and have rules
# for and which we need to fetch
for key, event_id in current_state_ids.iteritems():
if key[0] != EventTypes.Member:
continue
res = self.member_map.get(event_id, None)
if res:
user_id, state = res
if state == Membership.JOIN:
rules = self.rules_by_user.get(user_id, None)
if rules:
ret_rules_by_user[user_id] = rules
continue
user_id = key[1]
if not self.is_mine_id(user_id):
continue
if self.store.get_if_app_services_interested_in_user(user_id):
continue
# If a user has left a room we remove their push rule. If they
# joined then we readd it later in _update_rules_with_member_event_ids
ret_rules_by_user.pop(user_id, None)
missing_member_event_ids[user_id] = event_id
if missing_member_event_ids:
# If we have some memebr events we haven't seen, look them up
# and fetch push rules for them if appropriate.
yield self._update_rules_with_member_event_ids(
ret_rules_by_user, missing_member_event_ids, state_group
)
defer.returnValue(ret_rules_by_user)
@defer.inlineCallbacks
def _update_rules_with_member_event_ids(self, ret_rules_by_user, member_event_ids,
state_group):
"""Update the partially filled rules_by_user dict by fetching rules for
any newly joined users in the `member_event_ids` list.
Args:
ret_rules_by_user (dict): Partiallly filled dict of push rules. Gets
updated with any new rules.
member_event_ids (list): List of event ids for membership events that
have happened since the last time we filled rules_by_user
state_group: The state group we are currently computing push rules
for. Used when updating the cache.
"""
sequence = self.sequence
rows = yield self.store._simple_select_many_batch(
table="room_memberships",
column="event_id",
iterable=member_event_ids.values(),
retcols=('user_id', 'membership', 'event_id'),
keyvalues={},
batch_size=500,
desc="_get_rules_for_member_event_ids",
)
members = {
row["event_id"]: (row["user_id"], row["membership"])
for row in rows
}
interested_in_user_ids = set(
user_id for user_id, membership in members.itervalues()
if membership == Membership.JOIN
)
if_users_with_pushers = yield self.store.get_if_users_have_pushers(
interested_in_user_ids,
on_invalidate=self.invalidate_all_cb,
)
user_ids = set(
uid for uid, have_pusher in if_users_with_pushers.iteritems() if have_pusher
)
users_with_receipts = yield self.store.get_users_with_read_receipts_in_room(
self.room_id, on_invalidate=self.invalidate_all_cb,
)
# any users with pushers must be ours: they have pushers
for uid in users_with_receipts:
if uid in interested_in_user_ids:
user_ids.add(uid)
rules_by_user = yield self.store.bulk_get_push_rules(
user_ids, on_invalidate=self.invalidate_all_cb,
)
ret_rules_by_user.update(
item for item in rules_by_user.iteritems() if item[0] is not None
)
self.update_cache(sequence, members, ret_rules_by_user, state_group)
def invalidate_all(self):
# Note: Don't hand this function directly to an invalidation callback
# as it keeps a reference to self and will stop this instance from being
# GC'd if it gets dropped from the rules_to_user cache. Instead use
# `self.invalidate_all_cb`
self.sequence += 1
self.state_group = object()
self.member_map = {}
self.rules_by_user = {}
def update_cache(self, sequence, members, rules_by_user, state_group):
if sequence == self.sequence:
self.member_map.update(members)
self.rules_by_user = rules_by_user
self.state_group = state_group
class _Invalidation(namedtuple("_Invalidation", ("cache", "room_id"))):
# We rely on _CacheContext implementing __eq__ and __hash__ sensibly,
# which namedtuple does for us (i.e. two _CacheContext are the same if
# their caches and keys match). This is important in particular to
# dedupe when we add callbacks to lru cache nodes, otherwise the number
# of callbacks would grow.
def __call__(self):
rules = self.cache.get(self.room_id, None, update_metrics=False)
if rules:
rules.invalidate_all()