Don't recalculate event ID so often in sync (#1624)

* Don't bail so quickly in fetchMissingStateEvents

* Don't recalculate event IDs so often in sync API

* Add comments

* Fix comments

* Update to matrix-org/gomatrixserverlib@eb6a890

1 files changed, 6 insertions, 5 deletions

diff --git a/syncapi/storage/postgres/current_room_state_table.go b/syncapi/storage/postgres/current_room_state_table.go
index 12327278..554163e5 100644
--- a/syncapi/storage/postgres/current_room_state_table.go
+++ b/syncapi/storage/postgres/current_room_state_table.go
@@ -76,7 +76,7 @@ const selectRoomIDsWithMembershipSQL = "" +
 	"SELECT DISTINCT room_id FROM syncapi_current_room_state WHERE type = 'm.room.member' AND state_key = $1 AND membership = $2"
 
 const selectCurrentStateSQL = "" +
-	"SELECT headered_event_json FROM syncapi_current_room_state WHERE room_id = $1" +
+	"SELECT event_id, headered_event_json FROM syncapi_current_room_state WHERE room_id = $1" +
 	" AND ( $2::text[] IS NULL OR     sender  = ANY($2)  )" +
 	" AND ( $3::text[] IS NULL OR NOT(sender  = ANY($3)) )" +
 	" AND ( $4::text[] IS NULL OR     type LIKE ANY($4)  )" +
@@ -92,10 +92,10 @@ const selectStateEventSQL = "" +
 
 const selectEventsWithEventIDsSQL = "" +
 	// TODO: The session_id and transaction_id blanks are here because otherwise
-	// the rowsToStreamEvents expects there to be exactly five columns. We need to
+	// the rowsToStreamEvents expects there to be exactly six columns. We need to
 	// figure out if these really need to be in the DB, and if so, we need a
 	// better permanent fix for this. - neilalexander, 2 Jan 2020
-	"SELECT added_at, headered_event_json, 0 AS session_id, false AS exclude_from_sync, '' AS transaction_id" +
+	"SELECT event_id, added_at, headered_event_json, 0 AS session_id, false AS exclude_from_sync, '' AS transaction_id" +
 	" FROM syncapi_current_room_state WHERE event_id = ANY($1)"
 
 type currentRoomStateStatements struct {
@@ -278,13 +278,14 @@ func (s *currentRoomStateStatements) SelectEventsWithEventIDs(
 func rowsToEvents(rows *sql.Rows) ([]*gomatrixserverlib.HeaderedEvent, error) {
 	result := []*gomatrixserverlib.HeaderedEvent{}
 	for rows.Next() {
+		var eventID string
 		var eventBytes []byte
-		if err := rows.Scan(&eventBytes); err != nil {
+		if err := rows.Scan(&eventID, &eventBytes); err != nil {
 			return nil, err
 		}
 		// TODO: Handle redacted events
 		var ev gomatrixserverlib.HeaderedEvent
-		if err := json.Unmarshal(eventBytes, &ev); err != nil {
+		if err := ev.UnmarshalJSONWithEventID(eventBytes, eventID); err != nil {
 			return nil, err
 		}
 		result = append(result, &ev)