Make PerformJoin responsible for sending invite to RS input (#1277)

* Make PerformJoin send input membership event

* Invite input room events in separate goroutine

* Don't limit roomserver input events using request context

* Synchronous input room events

* Nope, that didn't work

* oops send state key to GetMembership

* Don't generate stripped state in client API more times than necessary, generate output events on receiving end of federated invite

* Commit membership updater changes

* Tweaks

clientapi/routing/createroom.go

@@ -371,20 +371,10 @@ func createRoom(
 	}
 
 	// If this is a direct message then we should invite the participants.
-	for _, invitee := range r.Invite {
-		// Build the invite event.
-		inviteEvent, err := buildMembershipEvent(
-			req.Context(), invitee, "", accountDB, device, gomatrixserverlib.Invite,
-			roomID, true, cfg, evTime, rsAPI, asAPI,
-		)
-		if err != nil {
-			util.GetLogger(req.Context()).WithError(err).Error("buildMembershipEvent failed")
-			continue
-		}
+	if len(r.Invite) > 0 {
 		// Build some stripped state for the invite.
-		candidates := append(gomatrixserverlib.UnwrapEventHeaders(builtEvents), inviteEvent.Event)
-		var strippedState []gomatrixserverlib.InviteV2StrippedState
-		for _, event := range candidates {
+		var globalStrippedState []gomatrixserverlib.InviteV2StrippedState
+		for _, event := range builtEvents {
 			switch event.Type() {
 			case gomatrixserverlib.MRoomName:
 				fallthrough
@@ -395,17 +385,35 @@ func createRoom(
 			case gomatrixserverlib.MRoomMember:
 				fallthrough
 			case gomatrixserverlib.MRoomJoinRules:
-				strippedState = append(
-					strippedState,
-					gomatrixserverlib.NewInviteV2StrippedState(&event),
+				ev := event.Event
+				globalStrippedState = append(
+					globalStrippedState,
+					gomatrixserverlib.NewInviteV2StrippedState(&ev),
 				)
 			}
 		}
+
+		// Process the invites.
+		for _, invitee := range r.Invite {
+			// Build the invite event.
+			inviteEvent, err := buildMembershipEvent(
+				req.Context(), invitee, "", accountDB, device, gomatrixserverlib.Invite,
+				roomID, true, cfg, evTime, rsAPI, asAPI,
+			)
+			if err != nil {
+				util.GetLogger(req.Context()).WithError(err).Error("buildMembershipEvent failed")
+				continue
+			}
+			inviteStrippedState := append(
+				globalStrippedState,
+				gomatrixserverlib.NewInviteV2StrippedState(&inviteEvent.Event),
+			)
 			// Send the invite event to the roomserver.
 			err = roomserverAPI.SendInvite(
-			req.Context(), rsAPI,
+				req.Context(),
+				rsAPI,
 				inviteEvent.Headered(roomVersion),
-			strippedState,         // invite room state
+				inviteStrippedState,   // invite room state
 				cfg.Matrix.ServerName, // send as server
 				nil,                   // transaction ID
 			)
@@ -421,6 +429,7 @@ func createRoom(
 				}
 			}
 		}
+	}
 
 	if r.Visibility == "public" {
 		// expose this room in the published room list

roomserver/api/wrapper.go

@@ -118,23 +118,6 @@ func SendInvite(
 		return response.Error
 	}
 
-	// Now send the invite event into the roomserver. If the room is known
-	// locally then this will succeed, notifying existing users in the room
-	// about the new invite. If the room isn't known locally then this will
-	// fail - and that's also OK.
-	inputReq := &InputRoomEventsRequest{
-		InputRoomEvents: []InputRoomEvent{
-			{
-				Kind:         KindNew,
-				Event:        inviteEvent,
-				AuthEventIDs: inviteEvent.AuthEventIDs(),
-				SendAsServer: string(sendAsServer),
-			},
-		},
-	}
-	inputRes := &InputRoomEventsResponse{}
-	_ = rsAPI.InputRoomEvents(ctx, inputReq, inputRes)
-
 	return nil
 }
 

roomserver/internal/perform_invite.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 
 	federationSenderAPI "github.com/matrix-org/dendrite/federationsender/api"
-	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/state"
 	"github.com/matrix-org/dendrite/roomserver/storage"
@@ -55,19 +54,15 @@ func (r *RoomserverInternalAPI) PerformInvite(
 		}
 	}
 
-	updater, err := r.DB.MembershipUpdater(ctx, roomID, targetUserID, isTargetLocal, req.RoomVersion)
+	var isAlreadyJoined bool
+	roomNID, err := r.DB.RoomNID(ctx, roomID)
+	if err == nil {
+		_, isAlreadyJoined, err = r.DB.GetMembership(ctx, roomNID, *event.StateKey())
 		if err != nil {
-		return fmt.Errorf("r.DB.MembershipUpdater: %w", err)
+			return fmt.Errorf("r.DB.GetMembership: %w", err)
 		}
-	succeeded := false
-	defer func() {
-		txerr := sqlutil.EndTransaction(updater, &succeeded)
-		if err == nil && txerr != nil {
-			err = txerr
 	}
-	}()
-
-	if updater.IsJoin() {
+	if isAlreadyJoined {
 		// If the user is joined to the room then that takes precedence over this
 		// invite event. It makes little sense to move a user that is already
 		// joined to the room into the invite state.
@@ -103,9 +98,11 @@ func (r *RoomserverInternalAPI) PerformInvite(
 	}
 
 	if isOriginLocal {
-		// check that the user is allowed to do this. We can only do this check if it is
-		// a local invite as we have the auth events, else we have to take it on trust.
-		_, err = checkAuthEvents(ctx, r.DB, req.Event, req.Event.AuthEventIDs())
+		// The invite originated locally. Therefore we have a responsibility to
+		// try and see if the user is allowed to make this invite. We can't do
+		// this for invites coming in over federation - we have to take those on
+		// trust.
+		_, err = checkAuthEvents(ctx, r.DB, event, event.AuthEventIDs())
 		if err != nil {
 			log.WithError(err).WithField("event_id", event.EventID()).WithField("auth_event_ids", event.AuthEventIDs()).Error(
 				"processInviteEvent.checkAuthEvents failed for event",
@@ -127,7 +124,7 @@ func (r *RoomserverInternalAPI) PerformInvite(
 		if req.SendAsServer != api.DoNotSendToOtherServers && !isTargetLocal {
 			fsReq := &federationSenderAPI.PerformInviteRequest{
 				RoomVersion:     req.RoomVersion,
-				Event:           req.Event,
+				Event:           event,
 				InviteRoomState: inviteState,
 			}
 			fsRes := &federationSenderAPI.PerformInviteResponse{}
@@ -141,6 +138,32 @@ func (r *RoomserverInternalAPI) PerformInvite(
 			}
 			event = fsRes.Event
 		}
+
+		// Send the invite event to the roomserver input stream. This will
+		// notify existing users in the room about the invite, update the
+		// membership table and ensure that the event is ready and available
+		// to use as an auth event when accepting the invite.
+		inputReq := &api.InputRoomEventsRequest{
+			InputRoomEvents: []api.InputRoomEvent{
+				{
+					Kind:         api.KindNew,
+					Event:        event,
+					AuthEventIDs: event.AuthEventIDs(),
+					SendAsServer: req.SendAsServer,
+				},
+			},
+		}
+		inputRes := &api.InputRoomEventsResponse{}
+		if err = r.InputRoomEvents(context.Background(), inputReq, inputRes); err != nil {
+			return fmt.Errorf("r.InputRoomEvents: %w", err)
+		}
+	} else {
+		// The invite originated over federation. Process the membership
+		// update, which will notify the sync API etc about the incoming
+		// invite.
+		updater, err := r.DB.MembershipUpdater(ctx, roomID, targetUserID, isTargetLocal, req.RoomVersion)
+		if err != nil {
+			return fmt.Errorf("r.DB.MembershipUpdater: %w", err)
 		}
 
 		unwrapped := event.Unwrap()
@@ -149,11 +172,15 @@ func (r *RoomserverInternalAPI) PerformInvite(
 			return fmt.Errorf("updateToInviteMembership: %w", err)
 		}
 
+		if err = updater.Commit(); err != nil {
+			return fmt.Errorf("updater.Commit: %w", err)
+		}
+
 		if err = r.WriteOutputEvents(roomID, outputUpdates); err != nil {
 			return fmt.Errorf("r.WriteOutputEvents: %w", err)
 		}
+	}
 
-	succeeded = true
 	return nil
 }
 

sytest-whitelist

@@ -455,3 +455,4 @@ Banned servers cannot backfill
 Inbound /v1/send_leave rejects leaves from other servers
 Guest users can accept invites to private rooms over federation
 AS user (not ghost) can join room without registering
+If user leaves room, remote user changes device and rejoins we see update in /sync and /keys/changes