dendrite/roomserver
Neil Alexander a308e61331
Federation sender API remodel (#988)
* Define an input API for the federationsender

* Wiring for rooomserver input API and federation sender input API

* Whoops, commit common too

* Merge input API into query API

* Rename FederationSenderQueryAPI to FederationSenderInternalAPI

* Fix dendritejs

* Rename Input to Perform

* Fix a couple of inputs -> performs

* Remove needless storage interface, add comments
2020-04-29 11:34:31 +01:00
..
alias Move /room/{roomID}/state endpoints into client API (#606) (#962) 2020-04-14 18:36:08 +01:00
api Federation sender API remodel (#988) 2020-04-29 11:34:31 +01:00
auth Implement backfill over federation (#938) 2020-03-24 12:20:10 +00:00
input Federation sender API remodel (#988) 2020-04-29 11:34:31 +01:00
query Implement backfill in the roomserver (#983) 2020-04-28 11:46:47 +01:00
state Use a single storage.Database interface (#978) 2020-04-24 10:38:58 +01:00
storage Implement backfill in the roomserver (#983) 2020-04-28 11:46:47 +01:00
types Invites v2 endpoint (#952) 2020-04-03 14:29:06 +01:00
version Set default room version to 4 (#957) 2020-04-16 12:53:27 +01:00
README.md use go module for dependencies (#594) 2019-05-21 21:56:55 +01:00
roomserver.go Federation sender API remodel (#988) 2020-04-29 11:34:31 +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 |
+---------------+-------------------+------------------+----------+