dendrite/roomserver
Neil Alexander 04dc019e5e
Don't set empty state snapshots
2020-10-21 16:21:36 +01:00
..
acls Move currentstateserver API to roomserver (#1387) 2020-09-03 17:20:54 +01:00
api KindOld (#1531) 2020-10-19 14:59:13 +01:00
auth Honour history_visibility when backfilling (#990) 2020-04-29 18:41:45 +01:00
internal Don't set empty state snapshots 2020-10-21 16:21:36 +01:00
inthttp Fetch missing auth events, implement QueryMissingAuthPrevEvents, try other servers in room for /event and /get_missing_events (#1450) 2020-09-29 13:40:29 +01:00
state Refactor forward extremities (#1556) 2020-10-21 15:37:07 +01:00
storage Always call overridden form of GetLatestEventsForUpdate (#1554) 2020-10-20 19:32:33 +01:00
types Implement rejected events (#1426) 2020-09-16 13:00:52 +01:00
version Set default room version to v6 (#1438) 2020-09-25 12:59:57 +01:00
README.md use go module for dependencies (#594) 2019-05-21 21:56:55 +01:00
roomserver.go Start Kafka connections for each component that needs them (#1527) 2020-10-15 13:27:13 +01:00
roomserver_test.go KindOld (#1531) 2020-10-19 14:59:13 +01:00

README.md

RoomServer

RoomServer Internals

Numeric IDs

To save space matrix string identifiers are mapped to local numeric IDs. The numeric IDs are more efficient to manipulate and use less space to store. The numeric IDs are never exposed in the API the room server exposes. The numeric IDs are converted to string IDs before they leave the room server. The numeric ID for a string ID is never 0 to avoid being confused with go's default zero value. Zero is used to indicate that there was no corresponding string ID. Well-known event types and event state keys are preassigned numeric IDs.

State Snapshot Storage

The room server stores the state of the matrix room at each event. For efficiency the state is stored as blocks of 3-tuples of numeric IDs for the event type, event state key and event ID. For further efficiency the state snapshots are stored as the combination of up to 64 these blocks. This allows blocks of the room state to be reused in multiple snapshots.

The resulting database tables look something like this:

+-------------------------------------------------------------------+
| Events                                                            |
+---------+-------------------+------------------+------------------+
| EventNID| EventTypeNID      | EventStateKeyNID | StateSnapshotNID |
+---------+-------------------+------------------+------------------+
|       1 | m.room.create   1 | ""             1 | <nil>          0 |
|       2 | m.room.member   2 | "@user:foo"    2 | <nil>          0 |
|       3 | m.room.member   2 | "@user:bar"    3 | {1,2}          1 |
|       4 | m.room.message  3 | <nil>          0 | {1,2,3}        2 |
|       5 | m.room.member   2 | "@user:foo"    2 | {1,2,3}        2 |
|       6 | m.room.message  3 | <nil>          0 | {1,3,6}        3 |
+---------+-------------------+------------------+------------------+

+----------------------------------------+
| State Snapshots                        |
+-----------------------+----------------+
| EventStateSnapshotNID | StateBlockNIDs |
+-----------------------+----------------|
|                     1 |           {1}  |
|                     2 |         {1,2}  |
|                     3 |       {1,2,3}  |
+-----------------------+----------------+

+-----------------------------------------------------------------+
| State Blocks                                                    |
+---------------+-------------------+------------------+----------+
| StateBlockNID | EventTypeNID      | EventStateKeyNID | EventNID |
+---------------+-------------------+------------------+----------+
|             1 | m.room.create   1 | ""             1 |        1 |
|             1 | m.room.member   2 | "@user:foo"    2 |        2 |
|             2 | m.room.member   2 | "@user:bar"    3 |        3 |
|             3 | m.room.member   2 | "@user:foo"    2 |        6 |
+---------------+-------------------+------------------+----------+