dendrite/roomserver
Neil Alexander 7a1fd123de
Improved state handling in /send (#1521)
* Capture errors

* Don't request only state key tuples needed for auth (we end up discarding room state this way)

* QueryStateAfterEvent returns all state when no tuples supplied

* Resolve state

* Comments
2020-10-14 12:39:37 +01:00
..
acls Move currentstateserver API to roomserver (#1387) 2020-09-03 17:20:54 +01:00
api Improved state handling in /send (#1521) 2020-10-14 12:39:37 +01:00
auth Honour history_visibility when backfilling (#990) 2020-04-29 18:41:45 +01:00
internal Improved state handling in /send (#1521) 2020-10-14 12:39:37 +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 Resolve state after event against current room state when determining latest state changes (#1479) 2020-10-05 17:47:08 +01:00
storage Wrap NewMembershipUpdater in a db writer (#1515) 2020-10-13 10:20:27 +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 Rename serverkeyapi to signingkeyserver (#1492) 2020-10-07 16:23:18 +01:00
roomserver_test.go Remove KindRewrite (#1481) 2020-10-06 11:05:00 +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 |
+---------------+-------------------+------------------+----------+