Specifically this is targetting invite rejections, where the leave
event is inside the leave block of the sync v2 response.
Previously, we would make a snapshot with this leave event. If the
proxy wasn't in this room, it would mean the room state would just
be the leave event, which is wrong. If the proxy was in the room,
then state would correctly be rolled forward.
With regression test. The behaviour is:
- Delete the connection, such that incoming requests will end up with M_UNKNOWN_POS
- The next request will then return HTTP 401.
This has knock-on effects:
- We no longer send HTTP 502 if /whoami returns 401, instead we return 401.
- When the token is expired (pollers get 401, the device is deleted from the DB).
- `Conn`s now expose a direct `OnUpdate(caches.Update)` function
for updates which concern a specific device ID.
- Add a bitset in `DeviceData` to indicate if the OTK or fallback keys were changed.
- Pass through the affected `DeviceID` in `pubsub.V2DeviceData` updates.
- Remove `DeviceDataTable.SelectFrom` as it was unused.
- Refactor how the poller invokes `OnE2EEData`: it now only does this if
there are changes to OTK counts and/or fallback key types and/or device lists,
and _only_ sends those fields, setting the rest to the zero value.
- Remove noisy logging.
- Add `caches.DeviceDataUpdate` which has no data but serves to wake-up the long poller.
- Only send OTK counts / fallback key types when they have changed, not constantly. This
matches the behaviour described in MSC3884
The entire flow now looks like:
- Poller notices a diff against in-memory version of otk count and invokes `OnE2EEData`
- Handler updates device data table, bumps the changed bit for otk count.
- Other handler gets the pubsub update, directly finds the `Conn` based on the `DeviceID`.
Invokes `OnUpdate(caches.DeviceDataUpdate)`
- This update is handled by the E2EE extension which then pulls the data out from the database
and returns it.
- On initial connections, all OTK / fallback data is returned.
Features:
- Add `typing` extension.
- Add `receipts` extension.
- Add comprehensive prometheus `/metrics` activated via `SYNCV3_PROM`.
- Add `SYNCV3_PPROF` support.
- Add `by_notification_level` sort order.
- Add `include_old_rooms` support.
- Add support for `$ME` and `$LAZY`.
- Add correct filtering when `*,*` is used as `required_state`.
- Add `num_live` to each room response to indicate how many timeline entries are live.
Bug fixes:
- Use a stricter comparison function on ranges: fixes an issue whereby UTs fail on go1.19 due to change in sorting algorithm.
- Send back an `errcode` on HTTP errors (e.g expired sessions).
- Remove `unsigned.txn_id` on insertion into the DB. Otherwise other users would see other users txn IDs :(
- Improve range delta algorithm: previously it didn't handle cases like `[0,20] -> [20,30]` and would panic.
- Send HTTP 400 for invalid range requests.
- Don't publish no-op unread counts which just adds extra noise.
- Fix leaking DB connections which could eventually consume all available connections.
- Ensure we always unblock WaitUntilInitialSync even on invalid access tokens. Other code relies on WaitUntilInitialSync() actually returning at _some_ point e.g on startup we have N workers which bound the number of concurrent pollers made at any one time, we need to not just hog a worker forever.
Improvements:
- Greatly improve startup times of sync3 handlers by improving `JoinedRoomsTracker`: a modest amount of data would take ~28s to create the handler, now it takes 4s.
- Massively improve initial initial v3 sync times, by refactoring `JoinedRoomsTracker`, from ~47s to <1s.
- Add `SlidingSyncUntil...` in tests to reduce races.
- Tweak the API shape of JoinedUsersForRoom to reduce state block processing time for large rooms from 63s to 39s.
- Add trace task for initial syncs.
- Include the proxy version in UA strings.
- HTTP errors now wait 1s before returning to stop clients tight-looping on error.
- Pending event buffer is now 2000.
- Index the room ID first to cull the most events when returning timeline entries. Speeds up `SelectLatestEventsBetween` by a factor of 8.
- Remove cancelled `m.room_key_requests` from the to-device inbox. Cuts down the amount of events in the inbox by ~94% for very large (20k+) inboxes, ~50% for moderate sized (200 events) inboxes. Adds book-keeping to remember the unacked to-device position for each client.
