MatrixSynapse/tests
Eric Eastwood fa8616e65c
Fix MSC3030 `/timestamp_to_event` returning `outliers` that it has no idea whether are near a gap or not (#14215)
Fix MSC3030 `/timestamp_to_event` endpoint returning `outliers` that it has no idea whether are near a gap or not (and therefore unable to determine whether it's actually the closest event). The reason Synapse doesn't know whether an `outlier` is next to a gap is because our gap checks rely on entries in the `event_edges`, `event_forward_extremeties`, and `event_backward_extremities` tables which is [not the case for `outliers`](2c63cdcc3f/docs/development/room-dag-concepts.md (outliers)).

Also fixes MSC3030 Complement `can_paginate_after_getting_remote_event_from_timestamp_to_event_endpoint` test flake.  Although this acted flakey in Complement, if `sync_partial_state` raced and beat us before `/timestamp_to_event`, then even if we retried the failing `/context` request it wouldn't work until we made this Synapse change. With this PR, Synapse will never return an `outlier` event so that test will always go and ask over federation.

Fix  https://github.com/matrix-org/synapse/issues/13944


### Why did this fail before? Why was it flakey?

Sleuthing the server logs on the [CI failure](https://github.com/matrix-org/synapse/actions/runs/3149623842/jobs/5121449357#step:5:5805), it looks like `hs2:/timestamp_to_event` found `$NP6-oU7mIFVyhtKfGvfrEQX949hQX-T-gvuauG6eurU` as an `outlier` event locally. Then when we went and asked for it via `/context`, since it's an `outlier`, it was filtered out of the results -> `You don't have permission to access that event.`

This is reproducible when `sync_partial_state` races and persists `$NP6-oU7mIFVyhtKfGvfrEQX949hQX-T-gvuauG6eurU` as an `outlier` before we evaluate `get_event_for_timestamp(...)`. To consistently reproduce locally, just add a delay at the [start of `get_event_for_timestamp(...)`](cb20b885cb/synapse/handlers/room.py (L1470-L1496)) so it always runs after `sync_partial_state` completes.

```py
from twisted.internet import task as twisted_task
d = twisted_task.deferLater(self.hs.get_reactor(), 3.5)
await d
```

In a run where it passes, on `hs2`, `get_event_for_timestamp(...)` finds a different event locally which is next to a gap and we request from a closer one from `hs1` which gets backfilled. And since the backfilled event is not an `outlier`, it's returned as expected during `/context`.

With this PR, Synapse will never return an `outlier` event so that test will always go and ask over federation.
2022-10-18 19:46:25 -05:00
..
api Support filtering the /messages API by relation type (MSC3874). (#14148) 2022-10-17 11:32:11 -04:00
app Remove configuration options for direct TCP replication. (#13647) 2022-09-06 07:50:02 +00:00
appservice Send the appservice access token as a header. (#13996) 2022-10-04 07:06:41 -04:00
config Reload cache factors from disk on SIGHUP (#12673) 2022-05-11 13:43:22 +00:00
crypto Remove direct refeferences to PyNaCl (use signedjson instead). (#12902) 2022-06-01 07:32:35 -04:00
events Register homeserver modules when creating test homeserver (#13558) 2022-08-19 16:52:20 +01:00
federation Always close _all_ `ijson` coroutines, even if doing so raises Exceptions (#14065) 2022-10-06 18:17:50 +00:00
handlers Avoid checking the event cache when backfilling events (#14164) 2022-10-18 10:33:35 +01:00
http Making parse_server_name more consistent (#14007) 2022-10-11 12:42:11 +00:00
logging Implementation of HTTP 307 response for MSC3886 POST endpoint (#14018) 2022-10-18 15:52:25 +00:00
module_api Reduce the number of tests using TCP replication. (#13543) 2022-08-19 08:25:24 -04:00
push Remove the experimental implementation of MSC3772. (#14094) 2022-10-12 06:26:39 -04:00
replication Track notification counts per thread (implement MSC3773). (#13776) 2022-10-04 09:47:04 -04:00
rest Fix MSC3030 `/timestamp_to_event` returning `outliers` that it has no idea whether are near a gap or not (#14215) 2022-10-18 19:46:25 -05:00
scripts Add some type hints to tests files (#12833) 2022-05-23 11:23:26 +00:00
server_notices Fix that sending server notices fail if avatar is `None` (#13566) 2022-08-23 09:48:35 +01:00
state Fix typechecks against twisted trunk (#13061) 2022-06-15 11:49:58 +01:00
storage Remove `_get_events_cache` check optimisation from `_have_seen_events_dict` (#14161) 2022-10-18 10:33:21 +01:00
test_utils Rename storage classes (#12913) 2022-05-31 12:17:50 +00:00
util Don't require `setuptools_rust` at runtime (#13952) 2022-09-29 20:16:08 +00:00
__init__.py Remove redundant "coding: utf-8" lines (#9786) 2021-04-14 15:34:27 +01:00
server.py Implementation of HTTP 307 response for MSC3886 POST endpoint (#14018) 2022-10-18 15:52:25 +00:00
test_distributor.py Replace assertEquals and friends with non-deprecated versions. (#12092) 2022-02-28 07:12:29 -05:00
test_event_auth.py Rename the `EventFormatVersions` enum values so that they line up with room version numbers. (#13706) 2022-09-07 11:08:20 +01:00
test_federation.py Track when the pulled event signature fails (#13815) 2022-10-03 14:53:29 -05:00
test_mau.py Remove remaining bits of groups code. (#12936) 2022-06-01 09:41:25 -04:00
test_metrics.py Add experimental configuration option to allow disabling legacy Prometheus metric names. (#13540) 2022-08-24 11:35:54 +00:00
test_phone_home.py Share some metrics between the Prometheus exporter and the phone home stats (#13671) 2022-09-05 10:26:43 +00:00
test_rust.py Add a stub Rust crate (#12595) 2022-09-06 19:01:37 +01:00
test_server.py Implementation of HTTP 307 response for MSC3886 POST endpoint (#14018) 2022-10-18 15:52:25 +00:00
test_state.py Faster room joins: avoid blocking when pulling events with missing prevs (#13355) 2022-07-26 12:39:23 +01:00
test_terms_auth.py Use literals in place of `HTTPStatus` constants in tests (#13463) 2022-08-05 16:59:09 +02:00
test_test_utils.py Replace assertEquals and friends with non-deprecated versions. (#12092) 2022-02-28 07:12:29 -05:00
test_types.py Fix error in `is_mine_id` when encountering a malformed ID (#13746) 2022-09-08 15:54:36 +01:00
test_visibility.py Rename test case method to `add_hashes_and_signatures_from_other_server` (#13255) 2022-07-12 18:46:32 +00:00
unittest.py Persist CreateRoom events to DB in a batch (#13800) 2022-09-28 10:11:48 +00:00
utils.py Update mypy and mypy-zope, attempt 3 (#13993) 2022-09-30 17:36:28 +01:00