Create a reusable error for invalid room info

roomserver/internal/helpers/auth.go

@@ -221,7 +221,7 @@ func loadAuthEvents(
 	}
 
 	if roomInfo == nil {
-		err = fmt.Errorf("cannot get events without room info")
+		err = types.ErrorInvalidRoomInfo
 		return
 	}
 	if result.events, err = db.Events(ctx, roomInfo.RoomVersion, eventNIDs); err != nil {

roomserver/internal/helpers/helpers.go

@@ -184,7 +184,7 @@ func GetMembershipsAtState(
 
 	// Get all of the events in this state
 	if roomInfo == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	stateEvents, err := db.Events(ctx, roomInfo.RoomVersion, eventNIDs)
 	if err != nil {
@@ -239,7 +239,7 @@ func LoadEvents(
 	ctx context.Context, db storage.RoomDatabase, roomInfo *types.RoomInfo, eventNIDs []types.EventNID,
 ) ([]gomatrixserverlib.PDU, error) {
 	if roomInfo == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	stateEvents, err := db.Events(ctx, roomInfo.RoomVersion, eventNIDs)
 	if err != nil {

roomserver/internal/input/input_events.go

@@ -806,7 +806,7 @@ func (r *Inputer) kickGuests(ctx context.Context, event gomatrixserverlib.PDU, r
 	}
 
 	if roomInfo == nil {
-		return fmt.Errorf("cannot get events without room info")
+		return types.ErrorInvalidRoomInfo
 	}
 	memberEvents, err := r.DB.Events(ctx, roomInfo.RoomVersion, membershipNIDs)
 	if err != nil {

roomserver/internal/perform/perform_backfill.go

@@ -564,7 +564,7 @@ func joinEventsFromHistoryVisibility(
 
 	// Get all of the events in this state
 	if roomInfo == nil {
-		return nil, gomatrixserverlib.HistoryVisibilityJoined, fmt.Errorf("cannot get events without room info")
+		return nil, gomatrixserverlib.HistoryVisibilityJoined, types.ErrorInvalidRoomInfo
 	}
 	stateEvents, err := db.Events(ctx, roomInfo.RoomVersion, eventNIDs)
 	if err != nil {

roomserver/internal/perform/perform_invite.go

@@ -270,7 +270,7 @@ func buildInviteStrippedState(
 		stateNIDs = append(stateNIDs, stateNID.EventNID)
 	}
 	if info == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	stateEvents, err := db.Events(ctx, info.RoomVersion, stateNIDs)
 	if err != nil {

roomserver/state/state.go

@@ -86,7 +86,7 @@ func (p *StateResolution) Resolve(ctx context.Context, eventID string) (*gomatri
 	}
 
 	if p.roomInfo == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	events, err := p.db.Events(ctx, p.roomInfo.RoomVersion, []types.EventNID{plNID})
 	if err != nil {
@@ -1139,7 +1139,7 @@ func (v *StateResolution) loadStateEvents(
 	}
 
 	if v.roomInfo == nil {
-		return nil, nil, fmt.Errorf("cannot get events without room info")
+		return nil, nil, types.ErrorInvalidRoomInfo
 	}
 	events, err := v.db.Events(ctx, v.roomInfo.RoomVersion, eventNIDs)
 	if err != nil {

roomserver/storage/shared/room_updater.go

@@ -118,7 +118,7 @@ func (u *RoomUpdater) StorePreviousEvents(eventNID types.EventNID, previousEvent
 
 func (u *RoomUpdater) Events(ctx context.Context, _ gomatrixserverlib.RoomVersion, eventNIDs []types.EventNID) ([]types.Event, error) {
 	if u.roomInfo == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	return u.d.events(ctx, u.txn, u.roomInfo.RoomVersion, eventNIDs)
 }

roomserver/storage/shared/storage.go

@@ -393,7 +393,7 @@ func (d *EventDatabase) eventsFromIDs(ctx context.Context, txn *sql.Tx, roomInfo
 	}
 
 	if roomInfo == nil {
-		return nil, fmt.Errorf("cannot get events without room info")
+		return nil, types.ErrorInvalidRoomInfo
 	}
 	return d.events(ctx, txn, roomInfo.RoomVersion, nids)
 }

roomserver/types/types.go

@@ -17,6 +17,7 @@ package types
 
 import (
 	"encoding/json"
+	"fmt"
 	"sort"
 	"strings"
 	"sync"
@@ -328,3 +329,5 @@ func (r *RoomInfo) CopyFrom(r2 *RoomInfo) {
 	r.stateSnapshotNID = r2.stateSnapshotNID
 	r.isStub = r2.isStub
 }
+
+var ErrorInvalidRoomInfo = fmt.Errorf("room info is invalid")