Try to use room version to get correct state resolution algorithm

roomserver/input/events.go

@@ -156,11 +156,8 @@ func calculateAndSetState(
 	stateAtEvent *types.StateAtEvent,
 	event gomatrixserverlib.Event,
 ) error {
-	// TODO: get the correct room version
-	roomState, err := state.Prepare(db, gomatrixserverlib.RoomVersionV1)
-	if err != nil {
-		return err
-	}
+	var err error
+	roomState := state.Prepare(db)
 
 	if input.HasState {
 		// We've been told what the state at the event is so we don't need to calculate it.

roomserver/input/latest_events.go

@@ -178,11 +178,7 @@ func (u *latestEventsUpdater) doUpdateLatestEvents() error {
 
 func (u *latestEventsUpdater) latestState() error {
 	var err error
-	// TODO: get the correct room version
-	roomState, err := state.Prepare(u.db, gomatrixserverlib.RoomVersionV1)
-	if err != nil {
-		return err
-	}
+	roomState := state.Prepare(u.db)
 
 	latestStateAtEvents := make([]types.StateAtEvent, len(u.latest))
 	for i := range u.latest {

roomserver/query/query.go

@@ -111,10 +111,7 @@ func (r *RoomserverQueryAPI) QueryLatestEventsAndState(
 		return err
 	}
 
-	roomState, err := state.Prepare(r.DB, roomVersion)
-	if err != nil {
-		return err
-	}
+	roomState := state.Prepare(r.DB)
 
 	response.QueryLatestEventsAndStateRequest = *request
 	roomNID, err := r.DB.RoomNID(ctx, request.RoomID)
@@ -164,10 +161,7 @@ func (r *RoomserverQueryAPI) QueryStateAfterEvents(
 		return err
 	}
 
-	roomState, err := state.Prepare(r.DB, roomVersion)
-	if err != nil {
-		return err
-	}
+	roomState := state.Prepare(r.DB)
 
 	response.QueryStateAfterEventsRequest = *request
 	roomNID, err := r.DB.RoomNID(ctx, request.RoomID)
@@ -192,7 +186,7 @@ func (r *RoomserverQueryAPI) QueryStateAfterEvents(
 
 	// Look up the currrent state for the requested tuples.
 	stateEntries, err := roomState.LoadStateAfterEventsForStringTuples(
-		ctx, prevStates, request.StateToFetch,
+		ctx, roomNID, prevStates, request.StateToFetch,
 	)
 	if err != nil {
 		return err
@@ -358,11 +352,7 @@ func (r *RoomserverQueryAPI) QueryMembershipsForRoom(
 func (r *RoomserverQueryAPI) getMembershipsBeforeEventNID(
 	ctx context.Context, eventNID types.EventNID, joinedOnly bool,
 ) ([]types.Event, error) {
-	// TODO: get the correct room version
-	roomState, err := state.Prepare(r.DB, gomatrixserverlib.RoomVersionV1)
-	if err != nil {
-		return []types.Event{}, err
-	}
+	roomState := state.Prepare(r.DB)
 	events := []types.Event{}
 	// Lookup the event NID
 	eIDs, err := r.DB.EventIDs(ctx, []types.EventNID{eventNID})
@@ -464,12 +454,7 @@ func (r *RoomserverQueryAPI) QueryServerAllowedToSeeEvent(
 func (r *RoomserverQueryAPI) checkServerAllowedToSeeEvent(
 	ctx context.Context, eventID string, serverName gomatrixserverlib.ServerName,
 ) (bool, error) {
-	// TODO: get the correct room version
-	roomState, err := state.Prepare(r.DB, gomatrixserverlib.RoomVersionV1)
-	if err != nil {
-		return false, err
-	}
-
+	roomState := state.Prepare(r.DB)
 	stateEntries, err := roomState.LoadStateAtEvent(ctx, eventID)
 	if err != nil {
 		return false, err
@@ -689,12 +674,7 @@ func (r *RoomserverQueryAPI) QueryStateAndAuthChain(
 }
 
 func (r *RoomserverQueryAPI) loadStateAtEventIDs(ctx context.Context, eventIDs []string) ([]gomatrixserverlib.Event, error) {
-	// TODO: get the correct room version
-	roomState, err := state.Prepare(r.DB, gomatrixserverlib.RoomVersionV1)
-	if err != nil {
-		return nil, err
-	}
-
+	roomState := state.Prepare(r.DB)
 	prevStates, err := r.DB.StateAtEventIDs(ctx, eventIDs)
 	if err != nil {
 		switch err.(type) {

roomserver/state/database/database.go

@@ -20,6 +20,7 @@ import (
 	"context"
 
 	"github.com/matrix-org/dendrite/roomserver/types"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 // A RoomStateDatabase has the storage APIs needed to load state from the database
@@ -61,4 +62,6 @@ type RoomStateDatabase interface {
 	Events(ctx context.Context, eventNIDs []types.EventNID) ([]types.Event, error)
 	// Look up snapshot NID for an event ID string
 	SnapshotNIDFromEventID(ctx context.Context, eventID string) (types.StateSnapshotNID, error)
+	// Look up a room version from the room NID.
+	GetRoomVersionForRoomNID(ctx context.Context, roomNID types.RoomNID) (gomatrixserverlib.RoomVersion, error)
 }

roomserver/state/state.go

@@ -33,25 +33,11 @@ import (
 
 type StateResolution struct {
 	db database.RoomStateDatabase
-	version gomatrixserverlib.RoomVersion
 }
 
-func Prepare(db database.RoomStateDatabase, version gomatrixserverlib.RoomVersion) (StateResolution, error) {
-	stateResAlgo, err := version.StateResAlgorithm()
-	if err != nil {
-		return StateResolution{}, err
-	}
-
-	switch stateResAlgo {
-	case gomatrixserverlib.StateResV1:
-		fallthrough
-	case gomatrixserverlib.StateResV2:
+func Prepare(db database.RoomStateDatabase) StateResolution {
 	return StateResolution{
 		db: db,
-			version: version,
-		}, nil
-	default:
-		return StateResolution{}, errors.New("unsupported state resolution algorithm")
 	}
 }
 
@@ -350,7 +336,7 @@ func (v StateResolution) loadStateAtSnapshotForNumericTuples(
 // This is typically the state before an event.
 // Returns a sorted list of state entries or an error if there was a problem talking to the database.
 func (v StateResolution) LoadStateAfterEventsForStringTuples(
-	ctx context.Context,
+	ctx context.Context, roomNID types.RoomNID,
 	prevStates []types.StateAtEvent,
 	stateKeyTuples []gomatrixserverlib.StateKeyTuple,
 ) ([]types.StateEntry, error) {
@@ -358,14 +344,19 @@ func (v StateResolution) LoadStateAfterEventsForStringTuples(
 	if err != nil {
 		return nil, err
 	}
-	return v.loadStateAfterEventsForNumericTuples(ctx, prevStates, numericTuples)
+	return v.loadStateAfterEventsForNumericTuples(ctx, roomNID, prevStates, numericTuples)
 }
 
 func (v StateResolution) loadStateAfterEventsForNumericTuples(
-	ctx context.Context,
+	ctx context.Context, roomNID types.RoomNID,
 	prevStates []types.StateAtEvent,
 	stateKeyTuples []types.StateKeyTuple,
 ) ([]types.StateEntry, error) {
+	roomVersion, err := v.db.GetRoomVersionForRoomNID(ctx, roomNID)
+	if err != nil {
+		return nil, err
+	}
+
 	if len(prevStates) == 1 {
 		// Fast path for a single event.
 		prevState := prevStates[0]
@@ -408,7 +399,7 @@ func (v StateResolution) loadStateAfterEventsForNumericTuples(
 
 	// TODO: Add metrics for this as it could take a long time for big rooms
 	// with large conflicts.
-	fullState, _, _, err := v.calculateStateAfterManyEvents(ctx, prevStates)
+	fullState, _, _, err := v.calculateStateAfterManyEvents(ctx, roomVersion, prevStates)
 	if err != nil {
 		return nil, err
 	}
@@ -617,9 +608,13 @@ func (v StateResolution) calculateAndStoreStateAfterManyEvents(
 	prevStates []types.StateAtEvent,
 	metrics calculateStateMetrics,
 ) (types.StateSnapshotNID, error) {
+	roomVersion, err := v.db.GetRoomVersionForRoomNID(ctx, roomNID)
+	if err != nil {
+		return metrics.stop(0, err)
+	}
 
 	state, algorithm, conflictLength, err :=
-		v.calculateStateAfterManyEvents(ctx, prevStates)
+		v.calculateStateAfterManyEvents(ctx, roomVersion, prevStates)
 	metrics.algorithm = algorithm
 	if err != nil {
 		return metrics.stop(0, err)
@@ -633,7 +628,8 @@ func (v StateResolution) calculateAndStoreStateAfterManyEvents(
 }
 
 func (v StateResolution) calculateStateAfterManyEvents(
-	ctx context.Context, prevStates []types.StateAtEvent,
+	ctx context.Context, roomVersion gomatrixserverlib.RoomVersion,
+	prevStates []types.StateAtEvent,
 ) (state []types.StateEntry, algorithm string, conflictLength int, err error) {
 	var combined []types.StateEntry
 	// Conflict resolution.
@@ -668,7 +664,7 @@ func (v StateResolution) calculateStateAfterManyEvents(
 		}
 
 		var resolved []types.StateEntry
-		resolved, err = v.resolveConflicts(ctx, notConflicted, conflicts)
+		resolved, err = v.resolveConflicts(ctx, roomVersion, notConflicted, conflicts)
 		if err != nil {
 			algorithm = "_resolve_conflicts"
 			return
@@ -684,10 +680,10 @@ func (v StateResolution) calculateStateAfterManyEvents(
 }
 
 func (v StateResolution) resolveConflicts(
-	ctx context.Context,
+	ctx context.Context, version gomatrixserverlib.RoomVersion,
 	notConflicted, conflicted []types.StateEntry,
 ) ([]types.StateEntry, error) {
-	stateResAlgo, err := v.version.StateResAlgorithm()
+	stateResAlgo, err := version.StateResAlgorithm()
 	if err != nil {
 		return nil, err
 	}

roomserver/storage/interface.go

@@ -46,5 +46,4 @@ 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)
-	GetRoomVersionForRoomNID(ctx context.Context, roomNID types.RoomNID) (gomatrixserverlib.RoomVersion, error)
 }