# -*- 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.
from twisted.internet import defer
from ._base import BaseHandler
from synapse.api.constants import (
EventTypes, JoinRules,
)
from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
from synapse.util.async import concurrently_execute
from synapse.util.caches.descriptors import cachedInlineCallbacks
from synapse.util.caches.response_cache import ResponseCache
from synapse.types import ThirdPartyInstanceID
from collections import namedtuple
from unpaddedbase64 import encode_base64, decode_base64
import logging
import msgpack
logger = logging.getLogger(__name__)
REMOTE_ROOM_LIST_POLL_INTERVAL = 60 * 1000
# This is used to indicate we should only return rooms published to the main list.
EMTPY_THIRD_PARTY_ID = ThirdPartyInstanceID(None, None)
class RoomListHandler(BaseHandler):
def __init__(self, hs):
super(RoomListHandler, self).__init__(hs)
self.response_cache = ResponseCache(hs)
self.remote_response_cache = ResponseCache(hs, timeout_ms=30 * 1000)
def get_local_public_room_list(self, limit=None, since_token=None,
search_filter=None,
network_tuple=EMTPY_THIRD_PARTY_ID,):
"""Generate a local public room list.
There are multiple different lists: the main one plus one per third
party network. A client can ask for a specific list or to return all.
Args:
limit (int)
since_token (str)
search_filter (dict)
network_tuple (ThirdPartyInstanceID): Which public list to use.
This can be (None, None) to indicate the main list, or a particular
appservice and network id to use an appservice specific one.
Setting to None returns all public rooms across all lists.
"""
logger.info(
"Getting public room list: limit=%r, since=%r, search=%r, network=%r",
limit, since_token, bool(search_filter), network_tuple,
)
if search_filter:
# We explicitly don't bother caching searches or requests for
# appservice specific lists.
logger.info("Bypassing cache as search request.")
return self._get_public_room_list(
limit, since_token, search_filter, network_tuple=network_tuple,
)
key = (limit, since_token, network_tuple)
result = self.response_cache.get(key)
if not result:
logger.info("No cached result, calculating one.")
result = self.response_cache.set(
key,
preserve_fn(self._get_public_room_list)(
limit, since_token, network_tuple=network_tuple
)
)
else:
logger.info("Using cached deferred result.")
return make_deferred_yieldable(result)
@defer.inlineCallbacks
def _get_public_room_list(self, limit=None, since_token=None,
search_filter=None,
network_tuple=EMTPY_THIRD_PARTY_ID,):
if since_token and since_token != "END":
since_token = RoomListNextBatch.from_token(since_token)
else:
since_token = None
rooms_to_order_value = {}
rooms_to_num_joined = {}
newly_visible = []
newly_unpublished = []
if since_token:
stream_token = since_token.stream_ordering
current_public_id = yield self.store.get_current_public_room_stream_id()
public_room_stream_id = since_token.public_room_stream_id
newly_visible, newly_unpublished = yield self.store.get_public_room_changes(
public_room_stream_id, current_public_id,
network_tuple=network_tuple,
)
else:
stream_token = yield self.store.get_room_max_stream_ordering()
public_room_stream_id = yield self.store.get_current_public_room_stream_id()
room_ids = yield self.store.get_public_room_ids_at_stream_id(
public_room_stream_id, network_tuple=network_tuple,
)
# We want to return rooms in a particular order: the number of joined
# users. We then arbitrarily use the room_id as a tie breaker.
@defer.inlineCallbacks
def get_order_for_room(room_id):
# Most of the rooms won't have changed between the since token and
# now (especially if the since token is "now"). So, we can ask what
# the current users are in a room (that will hit a cache) and then
# check if the room has changed since the since token. (We have to
# do it in that order to avoid races).
# If things have changed then fall back to getting the current state
# at the since token.
joined_users = yield self.store.get_users_in_room(room_id)
if self.store.has_room_changed_since(room_id, stream_token):
latest_event_ids = yield self.store.get_forward_extremeties_for_room(
room_id, stream_token
)
if not latest_event_ids:
return
joined_users = yield self.state_handler.get_current_user_in_room(
room_id, latest_event_ids,
)
num_joined_users = len(joined_users)
rooms_to_num_joined[room_id] = num_joined_users
if num_joined_users == 0:
return
# We want larger rooms to be first, hence negating num_joined_users
rooms_to_order_value[room_id] = (-num_joined_users, room_id)
yield concurrently_execute(get_order_for_room, room_ids, 10)
sorted_entries = sorted(rooms_to_order_value.items(), key=lambda e: e[1])
sorted_rooms = [room_id for room_id, _ in sorted_entries]
# `sorted_rooms` should now be a list of all public room ids that is
# stable across pagination. Therefore, we can use indices into this
# list as our pagination tokens.
# Filter out rooms that we don't want to return
rooms_to_scan = [
r for r in sorted_rooms
if r not in newly_unpublished and rooms_to_num_joined[room_id] > 0
]
total_room_count = len(rooms_to_scan)
if since_token:
# Filter out rooms we've already returned previously
# `since_token.current_limit` is the index of the last room we
# sent down, so we exclude it and everything before/after it.
if since_token.direction_is_forward:
rooms_to_scan = rooms_to_scan[since_token.current_limit + 1:]
else:
rooms_to_scan = rooms_to_scan[:since_token.current_limit]
rooms_to_scan.reverse()
# Actually generate the entries. _append_room_entry_to_chunk will append to
# chunk but will stop if len(chunk) > limit
chunk = []
if limit and not search_filter:
step = limit + 1
for i in xrange(0, len(rooms_to_scan), step):
# We iterate here because the vast majority of cases we'll stop
# at first iteration, but occaisonally _append_room_entry_to_chunk
# won't append to the chunk and so we need to loop again.
# We don't want to scan over the entire range either as that
# would potentially waste a lot of work.
yield concurrently_execute(
lambda r: self._append_room_entry_to_chunk(
r, rooms_to_num_joined[r],
chunk, limit, search_filter
),
rooms_to_scan[i:i + step], 10
)
if len(chunk) >= limit + 1:
break
else:
yield concurrently_execute(
lambda r: self._append_room_entry_to_chunk(
r, rooms_to_num_joined[r],
chunk, limit, search_filter
),
rooms_to_scan, 5
)
chunk.sort(key=lambda e: (-e["num_joined_members"], e["room_id"]))
# Work out the new limit of the batch for pagination, or None if we
# know there are no more results that would be returned.
# i.e., [since_token.current_limit..new_limit] is the batch of rooms
# we've returned (or the reverse if we paginated backwards)
# We tried to pull out limit + 1 rooms above, so if we have <= limit
# then we know there are no more results to return
new_limit = None
if chunk and (not limit or len(chunk) > limit):
if not since_token or since_token.direction_is_forward:
if limit:
chunk = chunk[:limit]
last_room_id = chunk[-1]["room_id"]
else:
if limit:
chunk = chunk[-limit:]
last_room_id = chunk[0]["room_id"]
new_limit = sorted_rooms.index(last_room_id)
results = {
"chunk": chunk,
"total_room_count_estimate": total_room_count,
}
if since_token:
results["new_rooms"] = bool(newly_visible)
if not since_token or since_token.direction_is_forward:
if new_limit is not None:
results["next_batch"] = RoomListNextBatch(
stream_ordering=stream_token,
public_room_stream_id=public_room_stream_id,
current_limit=new_limit,
direction_is_forward=True,
).to_token()
if since_token:
results["prev_batch"] = since_token.copy_and_replace(
direction_is_forward=False,
current_limit=since_token.current_limit + 1,
).to_token()
else:
if new_limit is not None:
results["prev_batch"] = RoomListNextBatch(
stream_ordering=stream_token,
public_room_stream_id=public_room_stream_id,
current_limit=new_limit,
direction_is_forward=False,
).to_token()
if since_token:
results["next_batch"] = since_token.copy_and_replace(
direction_is_forward=True,
current_limit=since_token.current_limit - 1,
).to_token()
defer.returnValue(results)
@defer.inlineCallbacks
def _append_room_entry_to_chunk(self, room_id, num_joined_users, chunk, limit,
search_filter):
"""Generate the entry for a room in the public room list and append it
to the `chunk` if it matches the search filter
"""
if limit and len(chunk) > limit + 1:
# We've already got enough, so lets just drop it.
return
result = yield self.generate_room_entry(room_id, num_joined_users)
if result and _matches_room_entry(result, search_filter):
chunk.append(result)
@cachedInlineCallbacks(num_args=1, cache_context=True)
def generate_room_entry(self, room_id, num_joined_users, cache_context,
with_alias=True, allow_private=False):
"""Returns the entry for a room
"""
result = {
"room_id": room_id,
"num_joined_members": num_joined_users,
}
current_state_ids = yield self.store.get_current_state_ids(
room_id, on_invalidate=cache_context.invalidate,
)
event_map = yield self.store.get_events([
event_id for key, event_id in current_state_ids.iteritems()
if key[0] in (
EventTypes.JoinRules,
EventTypes.Name,
EventTypes.Topic,
EventTypes.CanonicalAlias,
EventTypes.RoomHistoryVisibility,
EventTypes.GuestAccess,
"m.room.avatar",
)
])
current_state = {
(ev.type, ev.state_key): ev
for ev in event_map.values()
}
# Double check that this is actually a public room.
join_rules_event = current_state.get((EventTypes.JoinRules, ""))
if join_rules_event:
join_rule = join_rules_event.content.get("join_rule", None)
if not allow_private and join_rule and join_rule != JoinRules.PUBLIC:
defer.returnValue(None)
if with_alias:
aliases = yield self.store.get_aliases_for_room(
room_id, on_invalidate=cache_context.invalidate
)
if aliases:
result["aliases"] = aliases
name_event = yield current_state.get((EventTypes.Name, ""))
if name_event:
name = name_event.content.get("name", None)
if name:
result["name"] = name
topic_event = current_state.get((EventTypes.Topic, ""))
if topic_event:
topic = topic_event.content.get("topic", None)
if topic:
result["topic"] = topic
canonical_event = current_state.get((EventTypes.CanonicalAlias, ""))
if canonical_event:
canonical_alias = canonical_event.content.get("alias", None)
if canonical_alias:
result["canonical_alias"] = canonical_alias
visibility_event = current_state.get((EventTypes.RoomHistoryVisibility, ""))
visibility = None
if visibility_event:
visibility = visibility_event.content.get("history_visibility", None)
result["world_readable"] = visibility == "world_readable"
guest_event = current_state.get((EventTypes.GuestAccess, ""))
guest = None
if guest_event:
guest = guest_event.content.get("guest_access", None)
result["guest_can_join"] = guest == "can_join"
avatar_event = current_state.get(("m.room.avatar", ""))
if avatar_event:
avatar_url = avatar_event.content.get("url", None)
if avatar_url:
result["avatar_url"] = avatar_url
defer.returnValue(result)
@defer.inlineCallbacks
def get_remote_public_room_list(self, server_name, limit=None, since_token=None,
search_filter=None, include_all_networks=False,
third_party_instance_id=None,):
if search_filter:
# We currently don't support searching across federation, so we have
# to do it manually without pagination
limit = None
since_token = None
res = yield self._get_remote_list_cached(
server_name, limit=limit, since_token=since_token,
include_all_networks=include_all_networks,
third_party_instance_id=third_party_instance_id,
)
if search_filter:
res = {"chunk": [
entry
for entry in list(res.get("chunk", []))
if _matches_room_entry(entry, search_filter)
]}
defer.returnValue(res)
def _get_remote_list_cached(self, server_name, limit=None, since_token=None,
search_filter=None, include_all_networks=False,
third_party_instance_id=None,):
repl_layer = self.hs.get_replication_layer()
if search_filter:
# We can't cache when asking for search
return repl_layer.get_public_rooms(
server_name, limit=limit, since_token=since_token,
search_filter=search_filter, include_all_networks=include_all_networks,
third_party_instance_id=third_party_instance_id,
)
key = (
server_name, limit, since_token, include_all_networks,
third_party_instance_id,
)
result = self.remote_response_cache.get(key)
if not result:
result = self.remote_response_cache.set(
key,
repl_layer.get_public_rooms(
server_name, limit=limit, since_token=since_token,
search_filter=search_filter,
include_all_networks=include_all_networks,
third_party_instance_id=third_party_instance_id,
)
)
return result
class RoomListNextBatch(namedtuple("RoomListNextBatch", (
"stream_ordering", # stream_ordering of the first public room list
"public_room_stream_id", # public room stream id for first public room list
"current_limit", # The number of previous rooms returned
"direction_is_forward", # Bool if this is a next_batch, false if prev_batch
))):
KEY_DICT = {
"stream_ordering": "s",
"public_room_stream_id": "p",
"current_limit": "n",
"direction_is_forward": "d",
}
REVERSE_KEY_DICT = {v: k for k, v in KEY_DICT.items()}
@classmethod
def from_token(cls, token):
return RoomListNextBatch(**{
cls.REVERSE_KEY_DICT[key]: val
for key, val in msgpack.loads(decode_base64(token)).items()
})
def to_token(self):
return encode_base64(msgpack.dumps({
self.KEY_DICT[key]: val
for key, val in self._asdict().items()
}))
def copy_and_replace(self, **kwds):
return self._replace(
**kwds
)
def _matches_room_entry(room_entry, search_filter):
if search_filter and search_filter.get("generic_search_term", None):
generic_search_term = search_filter["generic_search_term"].upper()
if generic_search_term in room_entry.get("name", "").upper():
return True
elif generic_search_term in room_entry.get("topic", "").upper():
return True
elif generic_search_term in room_entry.get("canonical_alias", "").upper():
return True
else:
return True
return False