summary refs log tree commit diff
path: root/tests/unittest.py
blob: ee2f78ab0163f8565a113ca0c433ee12c3c248a4 (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
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
# Copyright 2014-2016 OpenMarket Ltd
# Copyright 2018 New Vector
# Copyright 2019 Matrix.org Federation C.I.C
#
# 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 gc
import hashlib
import hmac
import json
import logging
import secrets
import time
from typing import (
    Any,
    Awaitable,
    Callable,
    ClassVar,
    Dict,
    Generic,
    Iterable,
    List,
    NoReturn,
    Optional,
    Tuple,
    Type,
    TypeVar,
    Union,
)
from unittest.mock import Mock, patch

import canonicaljson
import signedjson.key
import unpaddedbase64
from typing_extensions import Concatenate, ParamSpec, Protocol

from twisted.internet.defer import Deferred, ensureDeferred
from twisted.python.failure import Failure
from twisted.python.threadpool import ThreadPool
from twisted.test.proto_helpers import MemoryReactor, MemoryReactorClock
from twisted.trial import unittest
from twisted.web.resource import Resource
from twisted.web.server import Request

from synapse import events
from synapse.api.constants import EventTypes
from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersion
from synapse.config._base import Config, RootConfig
from synapse.config.homeserver import HomeServerConfig
from synapse.config.server import DEFAULT_ROOM_VERSION
from synapse.crypto.event_signing import add_hashes_and_signatures
from synapse.federation.transport.server import TransportLayerServer
from synapse.http.server import JsonResource
from synapse.http.site import SynapseRequest, SynapseSite
from synapse.logging.context import (
    SENTINEL_CONTEXT,
    LoggingContext,
    current_context,
    set_current_context,
)
from synapse.rest import RegisterServletsFunc
from synapse.server import HomeServer
from synapse.types import JsonDict, Requester, UserID, create_requester
from synapse.util import Clock
from synapse.util.httpresourcetree import create_resource_tree

from tests.server import (
    CustomHeaderType,
    FakeChannel,
    ThreadedMemoryReactorClock,
    get_clock,
    make_request,
    setup_test_homeserver,
)
from tests.test_utils import event_injection, setup_awaitable_errors
from tests.test_utils.logging_setup import setup_logging
from tests.utils import checked_cast, default_config, setupdb

setupdb()
setup_logging()

TV = TypeVar("TV")
_ExcType = TypeVar("_ExcType", bound=BaseException, covariant=True)

P = ParamSpec("P")
R = TypeVar("R")
S = TypeVar("S")


class _TypedFailure(Generic[_ExcType], Protocol):
    """Extension to twisted.Failure, where the 'value' has a certain type."""

    @property
    def value(self) -> _ExcType:
        ...


def around(target: TV) -> Callable[[Callable[Concatenate[S, P], R]], None]:
    """A CLOS-style 'around' modifier, which wraps the original method of the
    given instance with another piece of code.

    @around(self)
    def method_name(orig, *args, **kwargs):
        return orig(*args, **kwargs)
    """

    def _around(code: Callable[Concatenate[S, P], R]) -> None:
        name = code.__name__
        orig = getattr(target, name)

        def new(*args: P.args, **kwargs: P.kwargs) -> R:
            return code(orig, *args, **kwargs)

        setattr(target, name, new)

    return _around


_TConfig = TypeVar("_TConfig", Config, RootConfig)


def deepcopy_config(config: _TConfig) -> _TConfig:
    new_config: _TConfig

    if isinstance(config, RootConfig):
        new_config = config.__class__(config.config_files)  # type: ignore[arg-type]
    else:
        new_config = config.__class__(config.root)

    for attr_name in config.__dict__:
        if attr_name.startswith("__") or attr_name == "root":
            continue
        attr = getattr(config, attr_name)
        if isinstance(attr, Config):
            new_attr = deepcopy_config(attr)
        else:
            new_attr = attr

        setattr(new_config, attr_name, new_attr)

    return new_config


_make_homeserver_config_obj_cache: Dict[str, Union[RootConfig, Config]] = {}


def make_homeserver_config_obj(config: Dict[str, Any]) -> RootConfig:
    """Creates a :class:`HomeServerConfig` instance with the given configuration dict.

    This is equivalent to::

        config_obj = HomeServerConfig()
        config_obj.parse_config_dict(config, "", "")

    but it keeps a cache of `HomeServerConfig` instances and deepcopies them as needed,
    to avoid validating the whole configuration every time.
    """
    cache_key = json.dumps(config)

    if cache_key in _make_homeserver_config_obj_cache:
        # Cache hit: reuse the existing instance
        config_obj = _make_homeserver_config_obj_cache[cache_key]
    else:
        # Cache miss; create the actual instance
        config_obj = HomeServerConfig()
        config_obj.parse_config_dict(config, "", "")

        # Add to the cache
        _make_homeserver_config_obj_cache[cache_key] = config_obj

    assert isinstance(config_obj, RootConfig)

    return deepcopy_config(config_obj)


class TestCase(unittest.TestCase):
    """A subclass of twisted.trial's TestCase which looks for 'loglevel'
    attributes on both itself and its individual test methods, to override the
    root logger's logging level while that test (case|method) runs."""

    def __init__(self, methodName: str):
        super().__init__(methodName)

        method = getattr(self, methodName)

        level = getattr(method, "loglevel", getattr(self, "loglevel", None))

        @around(self)
        def setUp(orig: Callable[[], R]) -> R:
            # if we're not starting in the sentinel logcontext, then to be honest
            # all future bets are off.
            if current_context():
                self.fail(
                    "Test starting with non-sentinel logging context %s"
                    % (current_context(),)
                )

            # Disable GC for duration of test. See below for why.
            gc.disable()

            old_level = logging.getLogger().level
            if level is not None and old_level != level:

                @around(self)
                def tearDown(orig: Callable[[], R]) -> R:
                    ret = orig()
                    logging.getLogger().setLevel(old_level)
                    return ret

                logging.getLogger().setLevel(level)

            # Trial messes with the warnings configuration, thus this has to be
            # done in the context of an individual TestCase.
            self.addCleanup(setup_awaitable_errors())

            return orig()

        # We want to force a GC to workaround problems with deferreds leaking
        # logcontexts when they are GCed (see the logcontext docs).
        #
        # The easiest way to do this would be to do a full GC after each test
        # run, but that is very expensive. Instead, we disable GC (above) for
        # the duration of the test so that we only need to run a gen-0 GC, which
        # is a lot quicker.

        @around(self)
        def tearDown(orig: Callable[[], R]) -> R:
            ret = orig()
            gc.collect(0)
            gc.enable()
            set_current_context(SENTINEL_CONTEXT)

            return ret

    def assertObjectHasAttributes(self, attrs: Dict[str, object], obj: object) -> None:
        """Asserts that the given object has each of the attributes given, and
        that the value of each matches according to assertEqual."""
        for key in attrs.keys():
            if not hasattr(obj, key):
                raise AssertionError("Expected obj to have a '.%s'" % key)
            try:
                self.assertEqual(attrs[key], getattr(obj, key))
            except AssertionError as e:
                raise (type(e))(f"Assert error for '.{key}':") from e

    def assert_dict(self, required: dict, actual: dict) -> None:
        """Does a partial assert of a dict.

        Args:
            required: The keys and value which MUST be in 'actual'.
            actual: The test result. Extra keys will not be checked.
        """
        for key in required:
            self.assertEqual(
                required[key], actual[key], msg="%s mismatch. %s" % (key, actual)
            )


def DEBUG(target: TV) -> TV:
    """A decorator to set the .loglevel attribute to logging.DEBUG.
    Can apply to either a TestCase or an individual test method."""
    target.loglevel = logging.DEBUG  # type: ignore[attr-defined]
    return target


def INFO(target: TV) -> TV:
    """A decorator to set the .loglevel attribute to logging.INFO.
    Can apply to either a TestCase or an individual test method."""
    target.loglevel = logging.INFO  # type: ignore[attr-defined]
    return target


def logcontext_clean(target: TV) -> TV:
    """A decorator which marks the TestCase or method as 'logcontext_clean'

    ... ie, any logcontext errors should cause a test failure
    """

    def logcontext_error(msg: str) -> NoReturn:
        raise AssertionError("logcontext error: %s" % (msg))

    patcher = patch("synapse.logging.context.logcontext_error", new=logcontext_error)
    return patcher(target)  # type: ignore[call-overload]


class HomeserverTestCase(TestCase):
    """
    A base TestCase that reduces boilerplate for HomeServer-using test cases.

    Defines a setUp method which creates a mock reactor, and instantiates a homeserver
    running on that reactor.

    There are various hooks for modifying the way that the homeserver is instantiated:

    * override make_homeserver, for example by making it pass different parameters into
      setup_test_homeserver.

    * override default_config, to return a modified configuration dictionary for use
      by setup_test_homeserver.

    * On a per-test basis, you can use the @override_config decorator to give a
      dictionary containing additional configuration settings to be added to the basic
      config dict.

    Attributes:
        servlets: List of servlet registration function.
        user_id (str): The user ID to assume if auth is hijacked.
        hijack_auth: Whether to hijack auth to return the user specified
        in user_id.
    """

    hijack_auth: ClassVar[bool] = True
    needs_threadpool: ClassVar[bool] = False
    servlets: ClassVar[List[RegisterServletsFunc]] = []

    def __init__(self, methodName: str):
        super().__init__(methodName)

        # see if we have any additional config for this test
        method = getattr(self, methodName)
        self._extra_config = getattr(method, "_extra_config", None)

    def setUp(self) -> None:
        """
        Set up the TestCase by calling the homeserver constructor, optionally
        hijacking the authentication system to return a fixed user, and then
        calling the prepare function.
        """
        self.reactor, self.clock = get_clock()
        self._hs_args = {"clock": self.clock, "reactor": self.reactor}
        self.hs = self.make_homeserver(self.reactor, self.clock)

        # Honour the `use_frozen_dicts` config option. We have to do this
        # manually because this is taken care of in the app `start` code, which
        # we don't run. Plus we want to reset it on tearDown.
        events.USE_FROZEN_DICTS = self.hs.config.server.use_frozen_dicts

        if self.hs is None:
            raise Exception("No homeserver returned from make_homeserver.")

        if not isinstance(self.hs, HomeServer):
            raise Exception("A homeserver wasn't returned, but %r" % (self.hs,))

        # create the root resource, and a site to wrap it.
        self.resource = self.create_test_resource()
        self.site = SynapseSite(
            logger_name="synapse.access.http.fake",
            site_tag=self.hs.config.server.server_name,
            config=self.hs.config.server.listeners[0],
            resource=self.resource,
            server_version_string="1",
            max_request_body_size=4096,
            reactor=self.reactor,
        )

        from tests.rest.client.utils import RestHelper

        self.helper = RestHelper(
            self.hs,
            checked_cast(MemoryReactorClock, self.hs.get_reactor()),
            self.site,
            getattr(self, "user_id", None),
        )

        if hasattr(self, "user_id"):
            if self.hijack_auth:
                assert self.helper.auth_user_id is not None
                token = "some_fake_token"

                # We need a valid token ID to satisfy foreign key constraints.
                token_id = self.get_success(
                    self.hs.get_datastores().main.add_access_token_to_user(
                        self.helper.auth_user_id,
                        token,
                        None,
                        None,
                    )
                )

                # This has to be a function and not just a Mock, because
                # `self.helper.auth_user_id` is temporarily reassigned in some tests
                async def get_requester(*args: Any, **kwargs: Any) -> Requester:
                    assert self.helper.auth_user_id is not None
                    return create_requester(
                        user_id=UserID.from_string(self.helper.auth_user_id),
                        access_token_id=token_id,
                    )

                # Type ignore: mypy doesn't like us assigning to methods.
                self.hs.get_auth().get_user_by_req = get_requester  # type: ignore[assignment]
                self.hs.get_auth().get_user_by_access_token = get_requester  # type: ignore[assignment]
                self.hs.get_auth().get_access_token_from_request = Mock(return_value=token)  # type: ignore[assignment]

        if self.needs_threadpool:
            self.reactor.threadpool = ThreadPool()  # type: ignore[assignment]
            self.addCleanup(self.reactor.threadpool.stop)
            self.reactor.threadpool.start()

        if hasattr(self, "prepare"):
            self.prepare(self.reactor, self.clock, self.hs)

    def tearDown(self) -> None:
        # Reset to not use frozen dicts.
        events.USE_FROZEN_DICTS = False

    def wait_on_thread(self, deferred: Deferred, timeout: int = 10) -> None:
        """
        Wait until a Deferred is done, where it's waiting on a real thread.
        """
        start_time = time.time()

        while not deferred.called:
            if start_time + timeout < time.time():
                raise ValueError("Timed out waiting for threadpool")
            self.reactor.advance(0.01)
            time.sleep(0.01)

    def wait_for_background_updates(self) -> None:
        """Block until all background database updates have completed."""
        store = self.hs.get_datastores().main
        while not self.get_success(
            store.db_pool.updates.has_completed_background_updates()
        ):
            self.get_success(
                store.db_pool.updates.do_next_background_update(False), by=0.1
            )

    def make_homeserver(
        self, reactor: ThreadedMemoryReactorClock, clock: Clock
    ) -> HomeServer:
        """
        Make and return a homeserver.

        Args:
            reactor: A Twisted Reactor, or something that pretends to be one.
            clock: The Clock, associated with the reactor.

        Returns:
            A homeserver suitable for testing.

        Function to be overridden in subclasses.
        """
        hs = self.setup_test_homeserver()
        return hs

    def create_test_resource(self) -> Resource:
        """
        Create a the root resource for the test server.

        The default calls `self.create_resource_dict` and builds the resultant dict
        into a tree.
        """
        root_resource = Resource()
        create_resource_tree(self.create_resource_dict(), root_resource)
        return root_resource

    def create_resource_dict(self) -> Dict[str, Resource]:
        """Create a resource tree for the test server

        A resource tree is a mapping from path to twisted.web.resource.

        The default implementation creates a JsonResource and calls each function in
        `servlets` to register servlets against it.
        """
        servlet_resource = JsonResource(self.hs)
        for servlet in self.servlets:
            servlet(self.hs, servlet_resource)
        return {
            "/_matrix/client": servlet_resource,
            "/_synapse/admin": servlet_resource,
        }

    def default_config(self) -> JsonDict:
        """
        Get a default HomeServer config dict.
        """
        config = default_config("test")

        # apply any additional config which was specified via the override_config
        # decorator.
        if self._extra_config is not None:
            config.update(self._extra_config)

        return config

    def prepare(
        self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer
    ) -> None:
        """
        Prepare for the test.  This involves things like mocking out parts of
        the homeserver, or building test data common across the whole test
        suite.

        Args:
            reactor: A Twisted Reactor, or something that pretends to be one.
            clock: The Clock, associated with the reactor.
            homeserver: The HomeServer to test against.

        Function to optionally be overridden in subclasses.
        """

    def make_request(
        self,
        method: Union[bytes, str],
        path: Union[bytes, str],
        content: Union[bytes, str, JsonDict] = b"",
        access_token: Optional[str] = None,
        request: Type[Request] = SynapseRequest,
        shorthand: bool = True,
        federation_auth_origin: Optional[bytes] = None,
        content_is_form: bool = False,
        await_result: bool = True,
        custom_headers: Optional[Iterable[CustomHeaderType]] = None,
        client_ip: str = "127.0.0.1",
    ) -> FakeChannel:
        """
        Create a SynapseRequest at the path using the method and containing the
        given content.

        Args:
            method: The HTTP request method ("verb").
            path: The HTTP path, suitably URL encoded (e.g. escaped UTF-8 & spaces
                and such). content (bytes or dict): The body of the request.
                JSON-encoded, if a dict.
            shorthand: Whether to try and be helpful and prefix the given URL
            with the usual REST API path, if it doesn't contain it.
            federation_auth_origin: if set to not-None, we will add a fake
                Authorization header pretenting to be the given server name.
            content_is_form: Whether the content is URL encoded form data. Adds the
                'Content-Type': 'application/x-www-form-urlencoded' header.

            await_result: whether to wait for the request to complete rendering. If
                 true (the default), will pump the test reactor until the the renderer
                 tells the channel the request is finished.

            custom_headers: (name, value) pairs to add as request headers

            client_ip: The IP to use as the requesting IP. Useful for testing
                ratelimiting.

        Returns:
            The FakeChannel object which stores the result of the request.
        """
        return make_request(
            self.reactor,
            self.site,
            method,
            path,
            content,
            access_token,
            request,
            shorthand,
            federation_auth_origin,
            content_is_form,
            await_result,
            custom_headers,
            client_ip,
        )

    def setup_test_homeserver(self, *args: Any, **kwargs: Any) -> HomeServer:
        """
        Set up the test homeserver, meant to be called by the overridable
        make_homeserver. It automatically passes through the test class's
        clock & reactor.

        Args:
            See tests.utils.setup_test_homeserver.

        Returns:
            synapse.server.HomeServer
        """
        kwargs = dict(kwargs)
        kwargs.update(self._hs_args)
        if "config" not in kwargs:
            config = self.default_config()
        else:
            config = kwargs["config"]

        # Parse the config from a config dict into a HomeServerConfig
        config_obj = make_homeserver_config_obj(config)
        kwargs["config"] = config_obj

        async def run_bg_updates() -> None:
            with LoggingContext("run_bg_updates"):
                self.get_success(stor.db_pool.updates.run_background_updates(False))

        hs = setup_test_homeserver(self.addCleanup, *args, **kwargs)
        stor = hs.get_datastores().main

        # Run the database background updates, when running against "master".
        if hs.__class__.__name__ == "TestHomeServer":
            self.get_success(run_bg_updates())

        return hs

    def pump(self, by: float = 0.0) -> None:
        """
        Pump the reactor enough that Deferreds will fire.
        """
        self.reactor.pump([by] * 100)

    def get_success(self, d: Awaitable[TV], by: float = 0.0) -> TV:
        deferred: Deferred[TV] = ensureDeferred(d)  # type: ignore[arg-type]
        self.pump(by=by)
        return self.successResultOf(deferred)

    def get_failure(
        self, d: Awaitable[Any], exc: Type[_ExcType]
    ) -> _TypedFailure[_ExcType]:
        """
        Run a Deferred and get a Failure from it. The failure must be of the type `exc`.
        """
        deferred: Deferred[Any] = ensureDeferred(d)  # type: ignore[arg-type]
        self.pump()
        return self.failureResultOf(deferred, exc)

    def get_success_or_raise(self, d: Awaitable[TV], by: float = 0.0) -> TV:
        """Drive deferred to completion and return result or raise exception
        on failure.
        """
        deferred: Deferred[TV] = ensureDeferred(d)  # type: ignore[arg-type]

        results: list = []
        deferred.addBoth(results.append)

        self.pump(by=by)

        if not results:
            self.fail(
                "Success result expected on {!r}, found no result instead".format(
                    deferred
                )
            )

        result = results[0]

        if isinstance(result, Failure):
            result.raiseException()

        return result

    def register_user(
        self,
        username: str,
        password: str,
        admin: Optional[bool] = False,
        displayname: Optional[str] = None,
    ) -> str:
        """
        Register a user. Requires the Admin API be registered.

        Args:
            username: The user part of the new user.
            password: The password of the new user.
            admin: Whether the user should be created as an admin or not.
            displayname: The displayname of the new user.

        Returns:
            The MXID of the new user.
        """
        self.hs.config.registration.registration_shared_secret = "shared"

        # Create the user
        channel = self.make_request("GET", "/_synapse/admin/v1/register")
        self.assertEqual(channel.code, 200, msg=channel.result)
        nonce = channel.json_body["nonce"]

        want_mac = hmac.new(key=b"shared", digestmod=hashlib.sha1)
        nonce_str = b"\x00".join([username.encode("utf8"), password.encode("utf8")])
        if admin:
            nonce_str += b"\x00admin"
        else:
            nonce_str += b"\x00notadmin"

        want_mac.update(nonce.encode("ascii") + b"\x00" + nonce_str)
        want_mac_digest = want_mac.hexdigest()

        body = {
            "nonce": nonce,
            "username": username,
            "displayname": displayname,
            "password": password,
            "admin": admin,
            "mac": want_mac_digest,
            "inhibit_login": True,
        }
        channel = self.make_request("POST", "/_synapse/admin/v1/register", body)
        self.assertEqual(channel.code, 200, channel.json_body)

        user_id = channel.json_body["user_id"]
        return user_id

    def register_appservice_user(
        self,
        username: str,
        appservice_token: str,
    ) -> Tuple[str, str]:
        """Register an appservice user as an application service.
        Requires the client-facing registration API be registered.

        Args:
            username: the user to be registered by an application service.
                Should NOT be a full username, i.e. just "localpart" as opposed to "@localpart:hostname"
            appservice_token: the acccess token for that application service.

        Raises: if the request to '/register' does not return 200 OK.

        Returns:
            The MXID of the new user, the device ID of the new user's first device.
        """
        channel = self.make_request(
            "POST",
            "/_matrix/client/r0/register",
            {
                "username": username,
                "type": "m.login.application_service",
            },
            access_token=appservice_token,
        )
        self.assertEqual(channel.code, 200, channel.json_body)
        return channel.json_body["user_id"], channel.json_body["device_id"]

    def login(
        self,
        username: str,
        password: str,
        device_id: Optional[str] = None,
        additional_request_fields: Optional[Dict[str, str]] = None,
        custom_headers: Optional[Iterable[CustomHeaderType]] = None,
    ) -> str:
        """
        Log in a user, and get an access token. Requires the Login API be registered.

        Args:
            username: The localpart to assign to the new user.
            password: The password to assign to the new user.
            device_id: An optional device ID to assign to the new device created during
                login.
            additional_request_fields: A dictionary containing any additional /login
                request fields and their values.
            custom_headers: Custom HTTP headers and values to add to the /login request.

        Returns:
            The newly registered user's Matrix ID.
        """
        body = {"type": "m.login.password", "user": username, "password": password}
        if device_id:
            body["device_id"] = device_id
        if additional_request_fields:
            body.update(additional_request_fields)

        channel = self.make_request(
            "POST",
            "/_matrix/client/r0/login",
            body,
            custom_headers=custom_headers,
        )
        self.assertEqual(channel.code, 200, channel.result)

        access_token = channel.json_body["access_token"]
        return access_token

    def create_and_send_event(
        self,
        room_id: str,
        user: UserID,
        soft_failed: bool = False,
        prev_event_ids: Optional[List[str]] = None,
    ) -> str:
        """
        Create and send an event.

        Args:
            soft_failed: Whether to create a soft failed event or not
            prev_event_ids: Explicitly set the prev events,
                or if None just use the default

        Returns:
            The new event's ID.
        """
        event_creator = self.hs.get_event_creation_handler()
        requester = create_requester(user)

        event, unpersisted_context = self.get_success(
            event_creator.create_event(
                requester,
                {
                    "type": EventTypes.Message,
                    "room_id": room_id,
                    "sender": user.to_string(),
                    "content": {"body": secrets.token_hex(), "msgtype": "m.text"},
                },
                prev_event_ids=prev_event_ids,
            )
        )
        context = self.get_success(unpersisted_context.persist(event))
        if soft_failed:
            event.internal_metadata.soft_failed = True

        self.get_success(
            event_creator.handle_new_client_event(
                requester, events_and_context=[(event, context)]
            )
        )

        return event.event_id

    def inject_room_member(self, room: str, user: str, membership: str) -> None:
        """
        Inject a membership event into a room.

        Deprecated: use event_injection.inject_room_member directly

        Args:
            room: Room ID to inject the event into.
            user: MXID of the user to inject the membership for.
            membership: The membership type.
        """
        self.get_success(
            event_injection.inject_member_event(self.hs, room, user, membership)
        )


class FederatingHomeserverTestCase(HomeserverTestCase):
    """
    A federating homeserver, set up to validate incoming federation requests
    """

    OTHER_SERVER_NAME = "other.example.com"
    OTHER_SERVER_SIGNATURE_KEY = signedjson.key.generate_signing_key("test")

    def prepare(self, reactor: MemoryReactor, clock: Clock, hs: HomeServer) -> None:
        super().prepare(reactor, clock, hs)

        # poke the other server's signing key into the key store, so that we don't
        # make requests for it
        verify_key = signedjson.key.get_verify_key(self.OTHER_SERVER_SIGNATURE_KEY)
        verify_key_id = "%s:%s" % (verify_key.alg, verify_key.version)

        self.get_success(
            hs.get_datastores().main.store_server_keys_json(
                self.OTHER_SERVER_NAME,
                verify_key_id,
                from_server=self.OTHER_SERVER_NAME,
                ts_now_ms=clock.time_msec(),
                ts_expires_ms=clock.time_msec() + 10000,
                key_json_bytes=canonicaljson.encode_canonical_json(
                    {
                        "verify_keys": {
                            verify_key_id: {
                                "key": signedjson.key.encode_verify_key_base64(
                                    verify_key
                                )
                            }
                        }
                    }
                ),
            )
        )

    def create_resource_dict(self) -> Dict[str, Resource]:
        d = super().create_resource_dict()
        d["/_matrix/federation"] = TransportLayerServer(self.hs)
        return d

    def make_signed_federation_request(
        self,
        method: str,
        path: str,
        content: Optional[JsonDict] = None,
        await_result: bool = True,
        custom_headers: Optional[Iterable[CustomHeaderType]] = None,
        client_ip: str = "127.0.0.1",
    ) -> FakeChannel:
        """Make an inbound signed federation request to this server

        The request is signed as if it came from "other.example.com", which our HS
        already has the keys for.
        """

        if custom_headers is None:
            custom_headers = []
        else:
            custom_headers = list(custom_headers)

        custom_headers.append(
            (
                "Authorization",
                _auth_header_for_request(
                    origin=self.OTHER_SERVER_NAME,
                    destination=self.hs.hostname,
                    signing_key=self.OTHER_SERVER_SIGNATURE_KEY,
                    method=method,
                    path=path,
                    content=content,
                ),
            )
        )

        return make_request(
            self.reactor,
            self.site,
            method=method,
            path=path,
            content=content if content is not None else "",
            shorthand=False,
            await_result=await_result,
            custom_headers=custom_headers,
            client_ip=client_ip,
        )

    def add_hashes_and_signatures_from_other_server(
        self,
        event_dict: JsonDict,
        room_version: RoomVersion = KNOWN_ROOM_VERSIONS[DEFAULT_ROOM_VERSION],
    ) -> JsonDict:
        """Adds hashes and signatures to the given event dict

        Returns:
             The modified event dict, for convenience
        """
        add_hashes_and_signatures(
            room_version,
            event_dict,
            signature_name=self.OTHER_SERVER_NAME,
            signing_key=self.OTHER_SERVER_SIGNATURE_KEY,
        )
        return event_dict


def _auth_header_for_request(
    origin: str,
    destination: str,
    signing_key: signedjson.key.SigningKey,
    method: str,
    path: str,
    content: Optional[JsonDict],
) -> str:
    """Build a suitable Authorization header for an outgoing federation request"""
    request_description: JsonDict = {
        "method": method,
        "uri": path,
        "destination": destination,
        "origin": origin,
    }
    if content is not None:
        request_description["content"] = content
    signature_base64 = unpaddedbase64.encode_base64(
        signing_key.sign(
            canonicaljson.encode_canonical_json(request_description)
        ).signature
    )
    return (
        f"X-Matrix origin={origin},"
        f"key={signing_key.alg}:{signing_key.version},"
        f"sig={signature_base64}"
    )


def override_config(extra_config: JsonDict) -> Callable[[TV], TV]:
    """A decorator which can be applied to test functions to give additional HS config

    For use

    For example:

        class MyTestCase(HomeserverTestCase):
            @override_config({"enable_registration": False, ...})
            def test_foo(self):
                ...

    Args:
        extra_config: Additional config settings to be merged into the default
            config dict before instantiating the test homeserver.
    """

    def decorator(func: TV) -> TV:
        # This attribute is being defined.
        func._extra_config = extra_config  # type: ignore[attr-defined]
        return func

    return decorator


def skip_unless(condition: bool, reason: str) -> Callable[[TV], TV]:
    """A test decorator which will skip the decorated test unless a condition is set

    For example:

    class MyTestCase(TestCase):
        @skip_unless(HAS_FOO, "Cannot test without foo")
        def test_foo(self):
            ...

    Args:
        condition: If true, the test will be skipped
        reason: the reason to give for skipping the test
    """

    def decorator(f: TV) -> TV:
        if not condition:
            f.skip = reason  # type: ignore
        return f

    return decorator