Replace IsRoomStub with RoomNIDExcludingStubs, fix query API to use that instead

roomserver/query/query.go

@@ -54,21 +54,13 @@ func (r *RoomserverQueryAPI) QueryLatestEventsAndState(
 	roomState := state.NewStateResolution(r.DB)
 
 	response.QueryLatestEventsAndStateRequest = *request
-	roomNID, err := r.DB.RoomNID(ctx, request.RoomID)
+	roomNID, err := r.DB.RoomNIDExcludingStubs(ctx, request.RoomID)
 	if err != nil {
 		return err
 	}
 	if roomNID == 0 {
 		return nil
 	}
-	isStub, err := r.DB.IsRoomStub(ctx, roomNID)
-	if err != nil {
-		return err
-	}
-	if isStub {
-		response.RoomExists = false
-		return nil
-	}
 	response.RoomExists = true
 	response.RoomVersion = roomVersion
 
@@ -122,21 +114,13 @@ func (r *RoomserverQueryAPI) QueryStateAfterEvents(
 	roomState := state.NewStateResolution(r.DB)
 
 	response.QueryStateAfterEventsRequest = *request
-	roomNID, err := r.DB.RoomNID(ctx, request.RoomID)
+	roomNID, err := r.DB.RoomNIDExcludingStubs(ctx, request.RoomID)
 	if err != nil {
 		return err
 	}
 	if roomNID == 0 {
 		return nil
 	}
-	isStub, err := r.DB.IsRoomStub(ctx, roomNID)
-	if err != nil {
-		return err
-	}
-	if isStub {
-		response.RoomExists = false
-		return nil
-	}
 	response.RoomExists = true
 	response.RoomVersion = roomVersion
 
@@ -665,21 +649,13 @@ func (r *RoomserverQueryAPI) QueryStateAndAuthChain(
 	response *api.QueryStateAndAuthChainResponse,
 ) error {
 	response.QueryStateAndAuthChainRequest = *request
-	roomNID, err := r.DB.RoomNID(ctx, request.RoomID)
+	roomNID, err := r.DB.RoomNIDExcludingStubs(ctx, request.RoomID)
 	if err != nil {
 		return err
 	}
 	if roomNID == 0 {
 		return nil
 	}
-	isStub, err := r.DB.IsRoomStub(ctx, roomNID)
-	if err != nil {
-		return err
-	}
-	if isStub {
-		response.RoomExists = false
-		return nil
-	}
 	response.RoomExists = true
 
 	roomVersion, err := r.DB.GetRoomVersionForRoom(ctx, request.RoomID)

roomserver/storage/interface.go

@@ -71,6 +71,10 @@ type Database interface {
 	GetLatestEventsForUpdate(ctx context.Context, roomNID types.RoomNID) (types.RoomRecentEventsUpdater, error)
 	GetTransactionEventID(ctx context.Context, transactionID string, sessionID int64, userID string) (string, error)
 	RoomNID(ctx context.Context, roomID string) (types.RoomNID, error)
+	// RoomNIDExcludingStubs is a special variation of RoomNID that will return 0 as if the room
+	// does not exist if the room has no latest events. This can happen when we've received an
+	// invite over federation for a room that we don't know anything else about yet.
+	RoomNIDExcludingStubs(ctx context.Context, roomID string) (types.RoomNID, error)
 	LatestEventIDs(ctx context.Context, roomNID types.RoomNID) ([]gomatrixserverlib.EventReference, types.StateSnapshotNID, int64, error)
 	GetInvitesForUser(ctx context.Context, roomNID types.RoomNID, targetUserNID types.EventStateKeyNID) (senderUserIDs []types.EventStateKeyNID, err error)
 	SetRoomAlias(ctx context.Context, alias string, roomID string, creatorUserID string) error
@@ -83,5 +87,4 @@ type Database interface {
 	GetMembershipEventNIDsForRoom(ctx context.Context, roomNID types.RoomNID, joinOnly bool) ([]types.EventNID, error)
 	EventsFromIDs(ctx context.Context, eventIDs []string) ([]types.Event, error)
 	GetRoomVersionForRoom(ctx context.Context, roomID string) (gomatrixserverlib.RoomVersion, error)
-	IsRoomStub(ctx context.Context, roomNID types.RoomNID) (bool, error)
 }

roomserver/storage/postgres/storage.go

@@ -471,6 +471,23 @@ func (d *Database) RoomNID(ctx context.Context, roomID string) (types.RoomNID, e
 	return roomNID, err
 }
 
+// RoomNIDExcludingStubs implements query.RoomserverQueryAPIDB
+func (d *Database) RoomNIDExcludingStubs(ctx context.Context, roomID string) (roomNID types.RoomNID, err error) {
+	roomNID, err = d.RoomNID(ctx, roomID)
+	if err != nil {
+		return
+	}
+	latestEvents, _, err := d.statements.selectLatestEventNIDs(ctx, roomNID)
+	if err != nil {
+		return
+	}
+	if len(latestEvents) == 0 {
+		roomNID = 0
+		return
+	}
+	return
+}
+
 // LatestEventIDs implements query.RoomserverQueryAPIDatabase
 func (d *Database) LatestEventIDs(
 	ctx context.Context, roomNID types.RoomNID,
@@ -772,16 +789,6 @@ func (d *Database) GetRoomVersionForRoomNID(
 	)
 }
 
-func (d *Database) IsRoomStub(
-	ctx context.Context, roomNID types.RoomNID,
-) (bool, error) {
-	nids, _, err := d.statements.selectLatestEventNIDs(ctx, roomNID)
-	if err != nil {
-		return false, err
-	}
-	return len(nids) == 0, nil
-}
-
 type transaction struct {
 	ctx context.Context
 	txn *sql.Tx

roomserver/storage/sqlite3/storage.go

@@ -590,6 +590,23 @@ func (d *Database) RoomNID(ctx context.Context, roomID string) (roomNID types.Ro
 	return
 }
 
+// RoomNIDExcludingStubs implements query.RoomserverQueryAPIDB
+func (d *Database) RoomNIDExcludingStubs(ctx context.Context, roomID string) (roomNID types.RoomNID, err error) {
+	roomNID, err = d.RoomNID(ctx, roomID)
+	if err != nil {
+		return
+	}
+	latestEvents, _, err := d.statements.selectLatestEventNIDs(ctx, nil, roomNID)
+	if err != nil {
+		return
+	}
+	if len(latestEvents) == 0 {
+		roomNID = 0
+		return
+	}
+	return
+}
+
 // LatestEventIDs implements query.RoomserverQueryAPIDatabase
 func (d *Database) LatestEventIDs(
 	ctx context.Context, roomNID types.RoomNID,
@@ -926,16 +943,6 @@ func (d *Database) GetRoomVersionForRoomNID(
 	)
 }
 
-func (d *Database) IsRoomStub(
-	ctx context.Context, roomNID types.RoomNID,
-) (bool, error) {
-	nids, _, err := d.statements.selectLatestEventNIDs(ctx, nil, roomNID)
-	if err != nil {
-		return false, err
-	}
-	return len(nids) == 0, nil
-}
-
 type transaction struct {
 	ctx context.Context
 	txn *sql.Tx