dendrite/roomserver
kegsay 2b34f88fde
Use ProtoEvent where needed instead of EventBuilder (#3075)
They are fundamentally different concepts, so should be represented as
such. Proto events are exchanged in /make_xxx calls over federation, and
made as "fledgling" events in /createRoom and general event sending.
*Building* events is a reasonably complex VERSION SPECIFIC process which
needs amongst other things, auth event providers, prev events, signing
keys, etc.

Requires https://github.com/matrix-org/gomatrixserverlib/pull/379
2023-05-04 11:17:42 +01:00
..
acls Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +01:00
api Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +01:00
auth Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +01:00
internal Use ProtoEvent where needed instead of EventBuilder (#3075) 2023-05-04 11:17:42 +01:00
producers Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +01:00
state Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +01:00
storage Use PDU in even more places (#3074) 2023-05-03 10:21:27 +01:00
types Use PDU not *Event in HeaderedEvent (#3073) 2023-05-02 15:03:16 +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 Use ProtoEvent where needed instead of EventBuilder (#3075) 2023-05-04 11:17:42 +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 |
+---------------+-------------------+------------------+----------+