summary refs log tree commit diff
path: root/synapse/handlers/room.py
blob: 1d9417ff1a8d59d1313ca0dde6bee36352dffe60 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
# -*- coding: utf-8 -*-
# Copyright 2014 - 2016 OpenMarket Ltd
# Copyright 2018 New Vector 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.

"""Contains functions for performing events on rooms."""
import itertools
import logging
import math
import string
from collections import OrderedDict

from six import iteritems, string_types

from twisted.internet import defer

from synapse.api.constants import (
    DEFAULT_ROOM_VERSION,
    KNOWN_ROOM_VERSIONS,
    EventTypes,
    JoinRules,
    RoomCreationPreset,
)
from synapse.api.errors import AuthError, Codes, NotFoundError, StoreError, SynapseError
from synapse.storage.state import StateFilter
from synapse.types import RoomAlias, RoomID, RoomStreamToken, StreamToken, UserID
from synapse.util import stringutils
from synapse.util.async_helpers import Linearizer
from synapse.visibility import filter_events_for_client

from ._base import BaseHandler

logger = logging.getLogger(__name__)

id_server_scheme = "https://"


class RoomCreationHandler(BaseHandler):

    PRESETS_DICT = {
        RoomCreationPreset.PRIVATE_CHAT: {
            "join_rules": JoinRules.INVITE,
            "history_visibility": "shared",
            "original_invitees_have_ops": False,
            "guest_can_join": True,
        },
        RoomCreationPreset.TRUSTED_PRIVATE_CHAT: {
            "join_rules": JoinRules.INVITE,
            "history_visibility": "shared",
            "original_invitees_have_ops": True,
            "guest_can_join": True,
        },
        RoomCreationPreset.PUBLIC_CHAT: {
            "join_rules": JoinRules.PUBLIC,
            "history_visibility": "shared",
            "original_invitees_have_ops": False,
            "guest_can_join": False,
        },
    }

    def __init__(self, hs):
        super(RoomCreationHandler, self).__init__(hs)

        self.spam_checker = hs.get_spam_checker()
        self.event_creation_handler = hs.get_event_creation_handler()
        self.room_member_handler = hs.get_room_member_handler()

        # linearizer to stop two upgrades happening at once
        self._upgrade_linearizer = Linearizer("room_upgrade_linearizer")

    @defer.inlineCallbacks
    def upgrade_room(self, requester, old_room_id, new_version):
        """Replace a room with a new room with a different version

        Args:
            requester (synapse.types.Requester): the user requesting the upgrade
            old_room_id (unicode): the id of the room to be replaced
            new_version (unicode): the new room version to use

        Returns:
            Deferred[unicode]: the new room id
        """
        yield self.ratelimit(requester)

        user_id = requester.user.to_string()

        with (yield self._upgrade_linearizer.queue(old_room_id)):
            # start by allocating a new room id
            r = yield self.store.get_room(old_room_id)
            if r is None:
                raise NotFoundError("Unknown room id %s" % (old_room_id,))
            new_room_id = yield self._generate_room_id(
                creator_id=user_id, is_public=r["is_public"],
            )

            # we create and auth the tombstone event before properly creating the new
            # room, to check our user has perms in the old room.
            tombstone_event, tombstone_context = (
                yield self.event_creation_handler.create_event(
                    requester, {
                        "type": EventTypes.Tombstone,
                        "state_key": "",
                        "room_id": old_room_id,
                        "sender": user_id,
                        "content": {
                            "body": "This room has been replaced",
                            "replacement_room": new_room_id,
                        }
                    },
                    token_id=requester.access_token_id,
                )
            )
            yield self.auth.check_from_context(tombstone_event, tombstone_context)

            yield self.clone_exiting_room(
                requester,
                old_room_id=old_room_id,
                new_room_id=new_room_id,
                new_room_version=new_version,
                tombstone_event_id=tombstone_event.event_id,
            )

            # now send the tombstone
            yield self.event_creation_handler.send_nonmember_event(
                requester, tombstone_event, tombstone_context,
            )

            # and finally, shut down the PLs in the old room, and update them in the new
            # room.
            old_room_state = yield tombstone_context.get_current_state_ids(self.store)

            yield self._update_upgraded_room_pls(
                requester, old_room_id, new_room_id, old_room_state,
            )

            defer.returnValue(new_room_id)

    @defer.inlineCallbacks
    def _update_upgraded_room_pls(
            self, requester, old_room_id, new_room_id, old_room_state,
    ):
        """Send updated power levels in both rooms after an upgrade

        Args:
            requester (synapse.types.Requester): the user requesting the upgrade
            old_room_id (unicode): the id of the room to be replaced
            new_room_id (unicode): the id of the replacement room
            old_room_state (dict[tuple[str, str], str]): the state map for the old room

        Returns:
            Deferred
        """
        old_room_pl_event_id = old_room_state.get((EventTypes.PowerLevels, ""))

        if old_room_pl_event_id is None:
            logger.warning(
                "Not supported: upgrading a room with no PL event. Not setting PLs "
                "in old room.",
            )
            return

        old_room_pl_state = yield self.store.get_event(old_room_pl_event_id)

        # we try to stop regular users from speaking by setting the PL required
        # to send regular events and invites to 'Moderator' level. That's normally
        # 50, but if the default PL in a room is 50 or more, then we set the
        # required PL above that.

        pl_content = dict(old_room_pl_state.content)
        users_default = int(pl_content.get("users_default", 0))
        restricted_level = max(users_default + 1, 50)

        updated = False
        for v in ("invite", "events_default"):
            current = int(pl_content.get(v, 0))
            if current < restricted_level:
                logger.info(
                    "Setting level for %s in %s to %i (was %i)",
                    v, old_room_id, restricted_level, current,
                )
                pl_content[v] = restricted_level
                updated = True
            else:
                logger.info(
                    "Not setting level for %s (already %i)",
                    v, current,
                )

        if updated:
            try:
                yield self.event_creation_handler.create_and_send_nonmember_event(
                    requester, {
                        "type": EventTypes.PowerLevels,
                        "state_key": '',
                        "room_id": old_room_id,
                        "sender": requester.user.to_string(),
                        "content": pl_content,
                    }, ratelimit=False,
                )
            except AuthError as e:
                logger.warning("Unable to update PLs in old room: %s", e)

        logger.info("Setting correct PLs in new room")
        yield self.event_creation_handler.create_and_send_nonmember_event(
            requester, {
                "type": EventTypes.PowerLevels,
                "state_key": '',
                "room_id": new_room_id,
                "sender": requester.user.to_string(),
                "content": old_room_pl_state.content,
            }, ratelimit=False,
        )

    @defer.inlineCallbacks
    def clone_exiting_room(
            self, requester, old_room_id, new_room_id, new_room_version,
            tombstone_event_id,
    ):
        """Populate a new room based on an old room

        Args:
            requester (synapse.types.Requester): the user requesting the upgrade
            old_room_id (unicode): the id of the room to be replaced
            new_room_id (unicode): the id to give the new room (should already have been
                created with _gemerate_room_id())
            new_room_version (unicode): the new room version to use
            tombstone_event_id (unicode|str): the ID of the tombstone event in the old
                room.
        Returns:
            Deferred[None]
        """
        user_id = requester.user.to_string()

        if not self.spam_checker.user_may_create_room(user_id):
            raise SynapseError(403, "You are not permitted to create rooms")

        # XXX check alias is free
        # canonical_alias = None

        # XXX create association in directory handler

        creation_content = {
            "room_version": new_room_version,
            "predecessor": {
                "room_id": old_room_id,
                "event_id": tombstone_event_id,
            }
        }

        initial_state = dict()

        types_to_copy = (
            (EventTypes.JoinRules, ""),
            (EventTypes.Name, ""),
            (EventTypes.Topic, ""),
            (EventTypes.RoomHistoryVisibility, ""),
            (EventTypes.GuestAccess, ""),
            (EventTypes.RoomAvatar, ""),
        )

        old_room_state_ids = yield self.store.get_filtered_current_state_ids(
            old_room_id, StateFilter.from_types(types_to_copy),
        )
        # map from event_id to BaseEvent
        old_room_state_events = yield self.store.get_events(old_room_state_ids.values())

        for k, old_event_id in iteritems(old_room_state_ids):
            old_event = old_room_state_events.get(old_event_id)
            if old_event:
                initial_state[k] = old_event.content

        yield self._send_events_for_new_room(
            requester,
            new_room_id,

            # we expect to override all the presets with initial_state, so this is
            # somewhat arbitrary.
            preset_config=RoomCreationPreset.PRIVATE_CHAT,

            invite_list=[],
            initial_state=initial_state,
            creation_content=creation_content,
        )

        # XXX invites/joins
        # XXX 3pid invites
        # XXX directory_handler.send_room_alias_update_event

    @defer.inlineCallbacks
    def create_room(self, requester, config, ratelimit=True,
                    creator_join_profile=None):
        """ Creates a new room.

        Args:
            requester (synapse.types.Requester):
                The user who requested the room creation.
            config (dict) : A dict of configuration options.
            ratelimit (bool): set to False to disable the rate limiter

            creator_join_profile (dict|None):
                Set to override the displayname and avatar for the creating
                user in this room. If unset, displayname and avatar will be
                derived from the user's profile. If set, should contain the
                values to go in the body of the 'join' event (typically
                `avatar_url` and/or `displayname`.

        Returns:
            Deferred[dict]:
                a dict containing the keys `room_id` and, if an alias was
                requested, `room_alias`.
        Raises:
            SynapseError if the room ID couldn't be stored, or something went
            horribly wrong.
            ResourceLimitError if server is blocked to some resource being
            exceeded
        """
        user_id = requester.user.to_string()

        self.auth.check_auth_blocking(user_id)

        if not self.spam_checker.user_may_create_room(user_id):
            raise SynapseError(403, "You are not permitted to create rooms")

        if ratelimit:
            yield self.ratelimit(requester)

        room_version = config.get("room_version", DEFAULT_ROOM_VERSION)
        if not isinstance(room_version, string_types):
            raise SynapseError(
                400,
                "room_version must be a string",
                Codes.BAD_JSON,
            )

        if room_version not in KNOWN_ROOM_VERSIONS:
            raise SynapseError(
                400,
                "Your homeserver does not support this room version",
                Codes.UNSUPPORTED_ROOM_VERSION,
            )

        if "room_alias_name" in config:
            for wchar in string.whitespace:
                if wchar in config["room_alias_name"]:
                    raise SynapseError(400, "Invalid characters in room alias")

            room_alias = RoomAlias(
                config["room_alias_name"],
                self.hs.hostname,
            )
            mapping = yield self.store.get_association_from_room_alias(
                room_alias
            )

            if mapping:
                raise SynapseError(
                    400,
                    "Room alias already taken",
                    Codes.ROOM_IN_USE
                )
        else:
            room_alias = None

        invite_list = config.get("invite", [])
        for i in invite_list:
            try:
                UserID.from_string(i)
            except Exception:
                raise SynapseError(400, "Invalid user_id: %s" % (i,))

        yield self.event_creation_handler.assert_accepted_privacy_policy(
            requester,
        )

        invite_3pid_list = config.get("invite_3pid", [])

        visibility = config.get("visibility", None)
        is_public = visibility == "public"

        room_id = yield self._generate_room_id(creator_id=user_id, is_public=is_public)

        if room_alias:
            directory_handler = self.hs.get_handlers().directory_handler
            yield directory_handler.create_association(
                requester=requester,
                room_id=room_id,
                room_alias=room_alias,
                servers=[self.hs.hostname],
                send_event=False,
            )

        preset_config = config.get(
            "preset",
            RoomCreationPreset.PRIVATE_CHAT
            if visibility == "private"
            else RoomCreationPreset.PUBLIC_CHAT
        )

        raw_initial_state = config.get("initial_state", [])

        initial_state = OrderedDict()
        for val in raw_initial_state:
            initial_state[(val["type"], val.get("state_key", ""))] = val["content"]

        creation_content = config.get("creation_content", {})

        # override any attempt to set room versions via the creation_content
        creation_content["room_version"] = room_version

        yield self._send_events_for_new_room(
            requester,
            room_id,
            preset_config=preset_config,
            invite_list=invite_list,
            initial_state=initial_state,
            creation_content=creation_content,
            room_alias=room_alias,
            power_level_content_override=config.get("power_level_content_override"),
            creator_join_profile=creator_join_profile,
        )

        if "name" in config:
            name = config["name"]
            yield self.event_creation_handler.create_and_send_nonmember_event(
                requester,
                {
                    "type": EventTypes.Name,
                    "room_id": room_id,
                    "sender": user_id,
                    "state_key": "",
                    "content": {"name": name},
                },
                ratelimit=False)

        if "topic" in config:
            topic = config["topic"]
            yield self.event_creation_handler.create_and_send_nonmember_event(
                requester,
                {
                    "type": EventTypes.Topic,
                    "room_id": room_id,
                    "sender": user_id,
                    "state_key": "",
                    "content": {"topic": topic},
                },
                ratelimit=False)

        for invitee in invite_list:
            content = {}
            is_direct = config.get("is_direct", None)
            if is_direct:
                content["is_direct"] = is_direct

            yield self.room_member_handler.update_membership(
                requester,
                UserID.from_string(invitee),
                room_id,
                "invite",
                ratelimit=False,
                content=content,
            )

        for invite_3pid in invite_3pid_list:
            id_server = invite_3pid["id_server"]
            address = invite_3pid["address"]
            medium = invite_3pid["medium"]
            yield self.hs.get_room_member_handler().do_3pid_invite(
                room_id,
                requester.user,
                medium,
                address,
                id_server,
                requester,
                txn_id=None,
            )

        result = {"room_id": room_id}

        if room_alias:
            result["room_alias"] = room_alias.to_string()
            yield directory_handler.send_room_alias_update_event(
                requester, room_id
            )

        defer.returnValue(result)

    @defer.inlineCallbacks
    def _send_events_for_new_room(
            self,
            creator,  # A Requester object.
            room_id,
            preset_config,
            invite_list,
            initial_state,
            creation_content,
            room_alias=None,
            power_level_content_override=None,
            creator_join_profile=None,
    ):
        def create(etype, content, **kwargs):
            e = {
                "type": etype,
                "content": content,
            }

            e.update(event_keys)
            e.update(kwargs)

            return e

        @defer.inlineCallbacks
        def send(etype, content, **kwargs):
            event = create(etype, content, **kwargs)
            yield self.event_creation_handler.create_and_send_nonmember_event(
                creator,
                event,
                ratelimit=False
            )

        config = RoomCreationHandler.PRESETS_DICT[preset_config]

        creator_id = creator.user.to_string()

        event_keys = {
            "room_id": room_id,
            "sender": creator_id,
            "state_key": "",
        }

        creation_content.update({"creator": creator_id})
        yield send(
            etype=EventTypes.Create,
            content=creation_content,
        )

        yield self.room_member_handler.update_membership(
            creator,
            creator.user,
            room_id,
            "join",
            ratelimit=False,
            content=creator_join_profile,
        )

        # We treat the power levels override specially as this needs to be one
        # of the first events that get sent into a room.
        pl_content = initial_state.pop((EventTypes.PowerLevels, ''), None)
        if pl_content is not None:
            yield send(
                etype=EventTypes.PowerLevels,
                content=pl_content,
            )
        else:
            power_level_content = {
                "users": {
                    creator_id: 100,
                },
                "users_default": 0,
                "events": {
                    EventTypes.Name: 50,
                    EventTypes.PowerLevels: 100,
                    EventTypes.RoomHistoryVisibility: 100,
                    EventTypes.CanonicalAlias: 50,
                    EventTypes.RoomAvatar: 50,
                },
                "events_default": 0,
                "state_default": 50,
                "ban": 50,
                "kick": 50,
                "redact": 50,
                "invite": 0,
            }

            if config["original_invitees_have_ops"]:
                for invitee in invite_list:
                    power_level_content["users"][invitee] = 100

            if power_level_content_override:
                power_level_content.update(power_level_content_override)

            yield send(
                etype=EventTypes.PowerLevels,
                content=power_level_content,
            )

        if room_alias and (EventTypes.CanonicalAlias, '') not in initial_state:
            yield send(
                etype=EventTypes.CanonicalAlias,
                content={"alias": room_alias.to_string()},
            )

        if (EventTypes.JoinRules, '') not in initial_state:
            yield send(
                etype=EventTypes.JoinRules,
                content={"join_rule": config["join_rules"]},
            )

        if (EventTypes.RoomHistoryVisibility, '') not in initial_state:
            yield send(
                etype=EventTypes.RoomHistoryVisibility,
                content={"history_visibility": config["history_visibility"]}
            )

        if config["guest_can_join"]:
            if (EventTypes.GuestAccess, '') not in initial_state:
                yield send(
                    etype=EventTypes.GuestAccess,
                    content={"guest_access": "can_join"}
                )

        for (etype, state_key), content in initial_state.items():
            yield send(
                etype=etype,
                state_key=state_key,
                content=content,
            )

    @defer.inlineCallbacks
    def _generate_room_id(self, creator_id, is_public):
        # autogen room IDs and try to create it. We may clash, so just
        # try a few times till one goes through, giving up eventually.
        attempts = 0
        while attempts < 5:
            try:
                random_string = stringutils.random_string(18)
                gen_room_id = RoomID(
                    random_string,
                    self.hs.hostname,
                ).to_string()
                if isinstance(gen_room_id, bytes):
                    gen_room_id = gen_room_id.decode('utf-8')
                yield self.store.store_room(
                    room_id=gen_room_id,
                    room_creator_user_id=creator_id,
                    is_public=is_public,
                )
                defer.returnValue(gen_room_id)
            except StoreError:
                attempts += 1
        raise StoreError(500, "Couldn't generate a room ID.")


class RoomContextHandler(object):
    def __init__(self, hs):
        self.hs = hs
        self.store = hs.get_datastore()

    @defer.inlineCallbacks
    def get_event_context(self, user, room_id, event_id, limit, event_filter):
        """Retrieves events, pagination tokens and state around a given event
        in a room.

        Args:
            user (UserID)
            room_id (str)
            event_id (str)
            limit (int): The maximum number of events to return in total
                (excluding state).
            event_filter (Filter|None): the filter to apply to the events returned
                (excluding the target event_id)

        Returns:
            dict, or None if the event isn't found
        """
        before_limit = math.floor(limit / 2.)
        after_limit = limit - before_limit

        users = yield self.store.get_users_in_room(room_id)
        is_peeking = user.to_string() not in users

        def filter_evts(events):
            return filter_events_for_client(
                self.store,
                user.to_string(),
                events,
                is_peeking=is_peeking
            )

        event = yield self.store.get_event(event_id, get_prev_content=True,
                                           allow_none=True)
        if not event:
            defer.returnValue(None)
            return

        filtered = yield(filter_evts([event]))
        if not filtered:
            raise AuthError(
                403,
                "You don't have permission to access that event."
            )

        results = yield self.store.get_events_around(
            room_id, event_id, before_limit, after_limit, event_filter
        )

        results["events_before"] = yield filter_evts(results["events_before"])
        results["events_after"] = yield filter_evts(results["events_after"])
        results["event"] = event

        if results["events_after"]:
            last_event_id = results["events_after"][-1].event_id
        else:
            last_event_id = event_id

        if event_filter and event_filter.lazy_load_members():
            state_filter = StateFilter.from_lazy_load_member_list(
                ev.sender
                for ev in itertools.chain(
                    results["events_before"],
                    (results["event"],),
                    results["events_after"],
                )
            )
        else:
            state_filter = StateFilter.all()

        # XXX: why do we return the state as of the last event rather than the
        # first? Shouldn't we be consistent with /sync?
        # https://github.com/matrix-org/matrix-doc/issues/687

        state = yield self.store.get_state_for_events(
            [last_event_id], state_filter=state_filter,
        )
        results["state"] = list(state[last_event_id].values())

        # We use a dummy token here as we only care about the room portion of
        # the token, which we replace.
        token = StreamToken.START

        results["start"] = token.copy_and_replace(
            "room_key", results["start"]
        ).to_string()

        results["end"] = token.copy_and_replace(
            "room_key", results["end"]
        ).to_string()

        defer.returnValue(results)


class RoomEventSource(object):
    def __init__(self, hs):
        self.store = hs.get_datastore()

    @defer.inlineCallbacks
    def get_new_events(
            self,
            user,
            from_key,
            limit,
            room_ids,
            is_guest,
            explicit_room_id=None,
    ):
        # We just ignore the key for now.

        to_key = yield self.get_current_key()

        from_token = RoomStreamToken.parse(from_key)
        if from_token.topological:
            logger.warn("Stream has topological part!!!! %r", from_key)
            from_key = "s%s" % (from_token.stream,)

        app_service = self.store.get_app_service_by_user_id(
            user.to_string()
        )
        if app_service:
            # We no longer support AS users using /sync directly.
            # See https://github.com/matrix-org/matrix-doc/issues/1144
            raise NotImplementedError()
        else:
            room_events = yield self.store.get_membership_changes_for_user(
                user.to_string(), from_key, to_key
            )

            room_to_events = yield self.store.get_room_events_stream_for_rooms(
                room_ids=room_ids,
                from_key=from_key,
                to_key=to_key,
                limit=limit or 10,
                order='ASC',
            )

            events = list(room_events)
            events.extend(e for evs, _ in room_to_events.values() for e in evs)

            events.sort(key=lambda e: e.internal_metadata.order)

            if limit:
                events[:] = events[:limit]

            if events:
                end_key = events[-1].internal_metadata.after
            else:
                end_key = to_key

        defer.returnValue((events, end_key))

    def get_current_key(self):
        return self.store.get_room_events_max_id()

    def get_current_key_for_room(self, room_id):
        return self.store.get_room_events_max_id(room_id)

    @defer.inlineCallbacks
    def get_pagination_rows(self, user, config, key):
        events, next_key = yield self.store.paginate_room_events(
            room_id=key,
            from_key=config.from_key,
            to_key=config.to_key,
            direction=config.direction,
            limit=config.limit,
        )

        defer.returnValue((events, next_key))