This is particularly a problem in a state reset scenario where the membership
might change without a corresponding event.
This PR is targeting a scenario where a state reset happens which causes
room membership to change. Previously, the cache would just hold onto
stale data and now we properly bust the cache in this scenario.
We have a few tests for these scenarios which you can see are now fixed
because we can remove the `FIXME` where we were previously manually
busting the cache in the test itself.
This is a general Synapse thing so by it's nature it helps out Sliding
Sync.
Fix https://github.com/element-hq/synapse/issues/17368
Prerequisite for https://github.com/element-hq/synapse/issues/17929
---
Match when are busting `_curr_state_delta_stream_cache`
Reset `sliding_sync_membership_snapshots` -> `forgotten` status when
membership changes (like rejoining a room).
Fix https://github.com/element-hq/synapse/issues/17781
### What was the problem before?
Previously, if someone used `/forget` on one of their rooms, it would
update `sliding_sync_membership_snapshots` as expected but when someone
rejoined the room (or had any membership change), the upsert didn't
overwrite and reset the `forgotten` status so it remained `forgotten`
and invisible down the Sliding Sync endpoint.
Performance optimization: We can avoid fetching rooms that the user has
left themselves (which could be a significant amount), then only add
back rooms that the user has `newly_left` (left in the token range of an
incremental sync). It's a lot faster to fetch less rooms than fetch them
all and throw them away in most cases. Since the user only leaves a room
(or is state reset out) once in a blue moon, we can avoid a lot of work.
Based on @erikjohnston's branch, erikj/ss_perf
---------
Co-authored-by: Erik Johnston <erik@matrix.org>
No need to sort if the range is large enough to cover all of the rooms
in the list. Previously, we would only do this optimization if the range
was exactly large enough.
Follow-up to https://github.com/element-hq/synapse/pull/17672
Move filters tests to rest layer in order to test the new (with sliding
sync tables) and fallback paths that Sliding Sync can use.
Also found a bug in the new path because it's not being tested which is
also fixed in this PR. We now take into account `has_known_state` when
filtering.
Spawning from
https://github.com/element-hq/synapse/pull/17662#discussion_r1755574791.
This should have been done when we started using the new sliding sync
tables in https://github.com/element-hq/synapse/pull/17630
We need to bust the `get_sliding_sync_rooms_for_user`
cache when the room encryption is updated and any
other field that is used in the query.
Follow-up to https://github.com/element-hq/synapse/pull/17630
- Bust cache for membership change (cross-reference
`get_rooms_for_user`)
- Bust cache for room `encryption` (cross-reference
`get_room_encryption`)
- Bust cache for `forgotten` (cross-reference
`did_forget`/`get_forgotten_rooms_for_user`)
I thought ruff check would also format, but it doesn't.
This runs ruff format in CI and dev scripts. The first commit is just a
run of `ruff format .` in the root directory.