Imported Upstream version 0.18.0

1 files changed, 400 insertions, 0 deletions

diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
new file mode 100644
index 00000000..5a533682
--- /dev/null
+++ b/synapse/handlers/room_list.py
@@ -0,0 +1,400 @@
+# -*- 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.async import concurrently_execute
+from synapse.util.caches.response_cache import ResponseCache
+
+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
+
+
+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):
+        if search_filter:
+            # We explicitly don't bother caching searches.
+            return self._get_public_room_list(limit, since_token, search_filter)
+
+        result = self.response_cache.get((limit, since_token))
+        if not result:
+            result = self.response_cache.set(
+                (limit, since_token),
+                self._get_public_room_list(limit, since_token)
+            )
+        return result
+
+    @defer.inlineCallbacks
+    def _get_public_room_list(self, limit=None, since_token=None,
+                              search_filter=None):
+        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 = {}
+        rooms_to_latest_event_ids = {}
+
+        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
+            )
+        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
+        )
+
+        # 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):
+            latest_event_ids = rooms_to_latest_event_ids.get(room_id, None)
+            if not latest_event_ids:
+                latest_event_ids = yield self.store.get_forward_extremeties_for_room(
+                    room_id, stream_token
+                )
+                rooms_to_latest_event_ids[room_id] = latest_event_ids
+
+            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
+        ]
+
+        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. _generate_room_entry 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 _generate_room_entry
+                # 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._generate_room_entry(
+                        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._generate_room_entry(
+                    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,
+        }
+
+        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 _generate_room_entry(self, room_id, num_joined_users, chunk, limit,
+                             search_filter):
+        if limit and len(chunk) > limit + 1:
+            # We've already got enough, so lets just drop it.
+            return
+
+        result = {
+            "room_id": room_id,
+            "num_joined_members": num_joined_users,
+        }
+
+        current_state_ids = yield self.state_handler.get_current_state_ids(room_id)
+
+        event_map = yield self.store.get_events([
+            event_id for key, event_id in current_state_ids.items()
+            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 join_rule and join_rule != JoinRules.PUBLIC:
+                defer.returnValue(None)
+
+        aliases = yield self.store.get_aliases_for_room(room_id)
+        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
+
+        if _matches_room_entry(result, search_filter):
+            chunk.append(result)
+
+    @defer.inlineCallbacks
+    def get_remote_public_room_list(self, server_name, limit=None, since_token=None,
+                                    search_filter=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,
+        )
+
+        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):
+        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,
+            )
+
+        result = self.remote_response_cache.get((server_name, limit, since_token))
+        if not result:
+            result = self.remote_response_cache.set(
+                (server_name, limit, since_token),
+                repl_layer.get_public_rooms(
+                    server_name, limit=limit, since_token=since_token,
+                    search_filter=search_filter,
+                )
+            )
+        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