Tweak control flow, comments, use GMSL history visibility type

clientapi/routing/aliases.go

@@ -44,7 +44,7 @@ func GetAliases(
 		return util.ErrorResponse(fmt.Errorf("rsAPI.QueryCurrentState: %w", err))
 	}
 
-	visibility := "invite"
+	visibility := gomatrixserverlib.HistoryVisibilityInvited
 	if historyVisEvent, ok := stateRes.StateEvents[stateTuple]; ok {
 		var err error
 		visibility, err = historyVisEvent.HistoryVisibility()

go.mod

@@ -34,7 +34,7 @@ require (
 	github.com/matrix-org/dugong v0.0.0-20210921133753-66e6b1c67e2e
 	github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91
 	github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16
-	github.com/matrix-org/gomatrixserverlib v0.0.0-20220607143425-e55d796fd0b3
+	github.com/matrix-org/gomatrixserverlib v0.0.0-20220613132209-aedb3fbb511a
 	github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48
 	github.com/matrix-org/util v0.0.0-20200807132607-55161520e1d4
 	github.com/mattn/go-sqlite3 v1.14.13

go.sum

@@ -418,8 +418,8 @@ github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91/go.mod h1
 github.com/matrix-org/gomatrix v0.0.0-20190528120928-7df988a63f26/go.mod h1:3fxX6gUjWyI/2Bt7J1OLhpCzOfO/bB3AiX0cJtEKud0=
 github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16 h1:ZtO5uywdd5dLDCud4r0r55eP4j9FuUNpl60Gmntcop4=
 github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16/go.mod h1:/gBX06Kw0exX1HrwmoBibFA98yBk/jxKpGVeyQbff+s=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20220607143425-e55d796fd0b3 h1:2eYcBt8Kg+nW/xIJY5x8Uo2dQLjUF+oxLap00uFC5l8=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20220607143425-e55d796fd0b3/go.mod h1:jX38yp3SSLJNftBg3PXU1ayd0PCLIiDHQ4xAc9DIixk=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20220613132209-aedb3fbb511a h1:jOkrb6twViAGTHHadA51sQwdloHT0Vx1MCptk9InTHo=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20220613132209-aedb3fbb511a/go.mod h1:jX38yp3SSLJNftBg3PXU1ayd0PCLIiDHQ4xAc9DIixk=
 github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48 h1:W0sjjC6yjskHX4mb0nk3p0fXAlbU5bAFUFeEtlrPASE=
 github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48/go.mod h1:ulJzsVOTssIVp1j/m5eI//4VpAGDkMt5NrRuAVX7wpc=
 github.com/matrix-org/util v0.0.0-20190711121626-527ce5ddefc7/go.mod h1:vVQlW/emklohkZnOPwD3LrZUBqdfsbiyO3p1lNV8F6U=

roomserver/api/output.go

@@ -162,7 +162,7 @@ type OutputNewRoomEvent struct {
 	// was specified
 	TransactionID *TransactionID `json:"transaction_id,omitempty"`
 	// The history visibility of the event.
-	HistoryVisibility string `json:"history_visibility"`
+	HistoryVisibility gomatrixserverlib.HistoryVisibility `json:"history_visibility"`
 }
 
 func (o *OutputNewRoomEvent) NeededStateEventIDs() ([]*gomatrixserverlib.HeaderedEvent, []string) {
@@ -190,7 +190,7 @@ func (o *OutputNewRoomEvent) NeededStateEventIDs() ([]*gomatrixserverlib.Headere
 type OutputOldRoomEvent struct {
 	// The Event.
 	Event             *gomatrixserverlib.HeaderedEvent    `json:"event"`
-	HistoryVisibility string                           `json:"history_visibility"`
+	HistoryVisibility gomatrixserverlib.HistoryVisibility `json:"history_visibility"`
 }
 
 // An OutputNewInviteEvent is written whenever an invite becomes active.

roomserver/internal/input/input_events.go

@@ -299,7 +299,7 @@ func (r *Inputer) processRoomEvent(
 	// allowed at the time, and also to get the history visibility. We won't
 	// bother doing this if the event was already rejected as it just ends up
 	// burning CPU time.
-	historyVisibility := "joined" // Default to restrictive.
+	historyVisibility := gomatrixserverlib.HistoryVisibilityJoined // Default to restrictive.
 	if rejectionErr == nil && !isRejected && !softfail {
 		var err error
 		historyVisibility, rejectionErr, err = r.processStateBefore(ctx, input, missingPrev)
@@ -376,7 +376,7 @@ func (r *Inputer) processRoomEvent(
 			input.SendAsServer,  // send as server
 			input.TransactionID, // transaction ID
 			input.HasState,      // rewrites state?
-			historyVisibility,   // the history visibility
+			historyVisibility,   // the history visibility before the event
 		); err != nil {
 			return fmt.Errorf("r.updateLatestEvents: %w", err)
 		}
@@ -430,11 +430,17 @@ func (r *Inputer) processStateBefore(
 	ctx context.Context,
 	input *api.InputRoomEvent,
 	missingPrev bool,
-) (historyVisibility string, rejectionErr error, err error) {
-	historyVisibility = "joined" // Default to restrictive.
+) (historyVisibility gomatrixserverlib.HistoryVisibility, rejectionErr error, err error) {
+	historyVisibility = gomatrixserverlib.HistoryVisibilityJoined // Default to restrictive.
 	event := input.Event.Unwrap()
+	isCreateEvent := event.Type() == gomatrixserverlib.MRoomCreate && event.StateKeyEquals("")
 	var stateBeforeEvent []*gomatrixserverlib.Event
-	if input.HasState {
+	switch {
+	case isCreateEvent:
+		// There's no state before a create event so there is nothing
+		// else to do.
+		return
+	case input.HasState:
 		// If we're overriding the state then we need to go and retrieve
 		// them from the database. It's a hard error if they are missing.
 		stateEvents, err := r.DB.EventsFromIDs(ctx, input.StateEventIDs)
@@ -445,12 +451,18 @@ func (r *Inputer) processStateBefore(
 		for _, entry := range stateEvents {
 			stateBeforeEvent = append(stateBeforeEvent, entry.Event)
 		}
-	} else if missingPrev {
-		// If we're missing prev events and still failed to fetch them
-		// before then we're stuck.
-		rejectionErr = fmt.Errorf("event %q should have prev events", event.EventID())
+	case missingPrev:
+		// We don't know all of the prev events, so we can't work out
+		// the state before the event. Reject it in that case.
+		rejectionErr = fmt.Errorf("event %q has missing prev events", event.EventID())
 		return
-	} else if event.Type() != gomatrixserverlib.MRoomCreate && len(event.PrevEventIDs()) > 0 {
+	case len(event.PrevEventIDs()) == 0:
+		// There should be prev events since it's not a create event.
+		// A non-create event that claims to have no prev events is
+		// invalid, so reject it.
+		rejectionErr = fmt.Errorf("event %q must have prev events", event.EventID())
+		return
+	default:
 		// For all non-create events, there must be prev events, so we'll
 		// ask the query API for the relevant tuples needed for auth. We
 		// will include the history visibility here even though we don't
@@ -480,20 +492,14 @@ func (r *Inputer) processStateBefore(
 		default:
 			stateBeforeEvent = gomatrixserverlib.UnwrapEventHeaders(stateBeforeRes.StateEvents)
 		}
-	} else if event.Type() != gomatrixserverlib.MRoomCreate && len(event.PrevEventIDs()) == 0 {
-		// Non-create events that don't have any prev event IDs are
-		// impossible in theory, so reject them.
-		rejectionErr = fmt.Errorf("event %q should have prev events", event.EventID())
-		return
 	}
-	if rejectionErr == nil {
-		// If we haven't rejected the event for some other reason by now,
-		// see whether the event is allowed against the state at the time.
+	// At this point, stateBeforeEvent should be populated either by
+	// the supplied state in the input request, or from the prev events.
+	// Check whether the event is allowed or not.
 	stateBeforeAuth := gomatrixserverlib.NewAuthEvents(stateBeforeEvent)
 	if rejectionErr = gomatrixserverlib.Allowed(event, &stateBeforeAuth); rejectionErr != nil {
 		return
 	}
-	}
 	// Work out what the history visibility was at the time of the
 	// event.
 	for _, event := range stateBeforeEvent {

roomserver/internal/input/input_latest_events.go

@@ -56,7 +56,7 @@ func (r *Inputer) updateLatestEvents(
 	sendAsServer string,
 	transactionID *api.TransactionID,
 	rewritesState bool,
-	historyVisibility string,
+	historyVisibility gomatrixserverlib.HistoryVisibility,
 ) (err error) {
 	span, ctx := opentracing.StartSpanFromContext(ctx, "updateLatestEvents")
 	defer span.Finish()
@@ -121,7 +121,8 @@ type latestEventsUpdater struct {
 	// The snapshots of current state before and after processing this event
 	oldStateNID types.StateSnapshotNID
 	newStateNID types.StateSnapshotNID
-	historyVisibility string
+	// The history visibility of the event itself (from the state before the event).
+	historyVisibility gomatrixserverlib.HistoryVisibility
 }
 
 func (u *latestEventsUpdater) doUpdateLatestEvents() error {

syncapi/routing/context.go

@@ -97,7 +97,7 @@ func Context(
 	state, _ := syncDB.CurrentState(ctx, roomID, &stateFilter, nil)
 	// verify the user is allowed to see the context for this room/event
 	for _, x := range state {
-		var hisVis string
+		var hisVis gomatrixserverlib.HistoryVisibility
 		hisVis, err = x.HistoryVisibility()
 		if err != nil {
 			continue