dendrite/roomserver
kegsay 6171310307
Use PDU interface (#3070)
We only use it in a few places currently, enough to get things to
compile and run. We should be using it in much more places.

Similarly, in some places we cast []PDU back to []*Event, we need to not
do that. Likewise, in some places we cast PDU to *Event, we need to not
do that. For now though, hopefully this is a start.
2023-04-27 16:35:19 +01:00
..
acls Remove gmsl.HeaderedEvent (#3068) 2023-04-27 12:54:20 +01:00
api Use PDU interface (#3070) 2023-04-27 16:35:19 +01:00
auth Add some roomserver UTs (#3067) 2023-04-27 08:07:13 +02:00
internal Use PDU interface (#3070) 2023-04-27 16:35:19 +01:00
producers Remove gmsl.HeaderedEvent (#3068) 2023-04-27 12:54:20 +01:00
state Use PDU interface (#3070) 2023-04-27 16:35:19 +01:00
storage Use PDU interface (#3070) 2023-04-27 16:35:19 +01:00
types Remove gmsl.HeaderedEvent (#3068) 2023-04-27 12:54:20 +01:00
version Use IRoomVersion (#3064) 2023-04-24 11:50:37 +01:00
README.md use go module for dependencies (#594) 2019-05-21 21:56:55 +01:00
roomserver_test.go Remove gmsl.HeaderedEvent (#3068) 2023-04-27 12:54:20 +01:00
roomserver.go Remove BaseDendrite (#3023) 2023-03-22 09:21:32 +01:00

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 |
+---------------+-------------------+------------------+----------+