49f760a30b
* Merge forward * Tidy up a bit * TODO: What to do with NextBatch here? * Replace SyncPosition with PaginationToken throughout syncapi * Fix PaginationTokens * Fix lint errors * Add a couple of missing functions into the syncapi external storage interface * Some updates based on review comments from @babolivier * Some updates based on review comments from @babolivier * argh whitespacing * Fix opentracing span * Remove dead code * Don't overshadow err (fix lint issue) * Handle extremities after inserting event into topology * Try insert event topology as ON CONFLICT DO NOTHING * Prevent OOB error in addRoomDeltaToResponse * Thwarted by gocyclo again * Fix NewPaginationTokenFromString, define unit test for it * Update pagination token test * Update sytest-whitelist * Hopefully fix some of the sync batch tokens * Remove extraneous sync position func * Revert to topology tokens in addRoomDeltaToResponse etc * Fix typo * Remove prevPDUPos as dead now that backwardTopologyPos is used instead * Fix selectEventsWithEventIDsSQL * Update sytest-blacklist * Update sytest-whitelist |
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|---|---|---|
| .. | ||
| alias | ||
| api | ||
| auth | ||
| input | ||
| query | ||
| state | ||
| storage | ||
| types | ||
| README.md | ||
| roomserver.go | ||
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 |
+---------------+-------------------+------------------+----------+