Actually we don't really need a goroutine here

federationapi/internal/perform.go

@@ -211,7 +211,7 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 
 	// Sanity-check the join response to ensure that it has a create
 	// event, that the room version is known, etc.
-	if err := sanityCheckAuthChain(respSendJoin.AuthEvents); err != nil {
+	if err = sanityCheckAuthChain(respSendJoin.AuthEvents); err != nil {
 		return fmt.Errorf("sanityCheckAuthChain: %w", err)
 	}
 
@@ -220,38 +220,34 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 	// to complete, but if the client does give up waiting, we'll
 	// still continue to process the join anyway so that we don't
 	// waste the effort.
-	go func() {
+	// TODO: Can we expand Check here to return a list of missing auth
-		// TODO: Can we expand Check here to return a list of missing auth
+	// events rather than failing one at a time?
-		// events rather than failing one at a time?
+	var respState *gomatrixserverlib.RespState
-		respState, err := respSendJoin.Check(context.Background(), r.keyRing, event, federatedAuthProvider(ctx, r.federation, r.keyRing, serverName))
+	respState, err = respSendJoin.Check(
-		if err != nil {
+		context.Background(),
-			logrus.WithFields(logrus.Fields{
+		r.keyRing,
-				"room_id": roomID,
+		event,
-				"user_id": userID,
+		federatedAuthProvider(ctx, r.federation, r.keyRing, serverName),
-			}).WithError(err).Error("Failed to process room join response")
+	)
-			return
+	if err != nil {
-		}
+		return fmt.Errorf("respSendJoin.Check: %w", err)
+	}
 
-		// If we successfully performed a send_join above then the other
+	// If we successfully performed a send_join above then the other
-		// server now thinks we're a part of the room. Send the newly
+	// server now thinks we're a part of the room. Send the newly
-		// returned state to the roomserver to update our local view.
+	// returned state to the roomserver to update our local view.
-		if err = roomserverAPI.SendEventWithState(
+	if err = roomserverAPI.SendEventWithState(
-			context.Background(),
+		context.Background(),
-			r.rsAPI,
+		r.rsAPI,
-			roomserverAPI.KindNew,
+		roomserverAPI.KindNew,
-			respState,
+		respState,
-			event.Headered(respMakeJoin.RoomVersion),
+		event.Headered(respMakeJoin.RoomVersion),
-			serverName,
+		serverName,
-			nil,
+		nil,
-			false,
+		false,
-		); err != nil {
+	); err != nil {
-			logrus.WithFields(logrus.Fields{
+		return fmt.Errorf("roomserverAPI.SendEventWithState: %w", err)
-				"room_id": roomID,
+	}
-				"user_id": userID,
-			}).WithError(err).Error("Failed to send room join response to roomserver")
-			return
-		}
-	}()
 
 	return nil
 }