Revert "Deduplicate OnIncomingStateRequest and OnIncomingStateTypeRequest"

This reverts commit 335035d66e.

clientapi/routing/routing.go

@@ -201,7 +201,7 @@ func Setup(
 		if err != nil {
 			return util.ErrorResponse(err)
 		}
-		return OnIncomingStateTypeRequest(req.Context(), device, rsAPI, vars["roomID"], "", "")
+		return OnIncomingStateRequest(req.Context(), device, rsAPI, vars["roomID"])
 	})).Methods(http.MethodGet, http.MethodOptions)
 
 	r0mux.Handle("/rooms/{roomID}/state/{type:[^/]+/?}", httputil.MakeAuthAPI("room_state", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
@@ -214,7 +214,8 @@ func Setup(
 		if strings.HasSuffix(eventType, "/") {
 			eventType = eventType[:len(eventType)-1]
 		}
-		return OnIncomingStateTypeRequest(req.Context(), device, rsAPI, vars["roomID"], eventType, "")
+		eventFormat := req.URL.Query().Get("format") == "event"
+		return OnIncomingStateTypeRequest(req.Context(), device, rsAPI, vars["roomID"], eventType, "", eventFormat)
 	})).Methods(http.MethodGet, http.MethodOptions)
 
 	r0mux.Handle("/rooms/{roomID}/state/{type}/{stateKey}", httputil.MakeAuthAPI("room_state", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
@@ -222,7 +223,8 @@ func Setup(
 		if err != nil {
 			return util.ErrorResponse(err)
 		}
-		return OnIncomingStateTypeRequest(req.Context(), device, rsAPI, vars["roomID"], vars["type"], vars["stateKey"])
+		eventFormat := req.URL.Query().Get("format") == "event"
+		return OnIncomingStateTypeRequest(req.Context(), device, rsAPI, vars["roomID"], vars["type"], vars["stateKey"], eventFormat)
 	})).Methods(http.MethodGet, http.MethodOptions)
 
 	r0mux.Handle("/rooms/{roomID}/state/{eventType:[^/]+/?}",

clientapi/routing/state.go

@@ -28,47 +28,162 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
-// OnIncomingStateTypeRequest is called when a client makes a request to either:
+type stateEventInStateResp struct {
-// - /rooms/{roomID}/state
+	gomatrixserverlib.ClientEvent
-// - /rooms/{roomID}/state/{type}/{statekey}
+	PrevContent   json.RawMessage `json:"prev_content,omitempty"`
-// The former will have evType and stateKey as "". The latter will specify them.
+	ReplacesState string          `json:"replaces_state,omitempty"`
-// It will look in current state to see if there is an event with that type
+}
-// and state key, if there is then (by default) we return the content. If the
+
-// history visibility restricts the room state then users who have left or
+// OnIncomingStateRequest is called when a client makes a /rooms/{roomID}/state
-// have been kicked/banned from the room will see the state from the time that
+// request. It will fetch all the state events from the specified room and will
-// they left.
+// append the necessary keys to them if applicable before returning them.
+// Returns an error if something went wrong in the process.
+// TODO: Check if the user is in the room. If not, check if the room's history
+// is publicly visible. Current behaviour is returning an empty array if the
+// user cannot see the room's history.
+func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI api.RoomserverInternalAPI, roomID string) util.JSONResponse {
+	var worldReadable bool
+	var wantLatestState bool
+
+	// First of all, get the latest state of the room. We need to do this
+	// so that we can look at the history visibility of the room. If the
+	// room is world-readable then we will always return the latest state.
+	stateRes := api.QueryLatestEventsAndStateResponse{}
+	if err := rsAPI.QueryLatestEventsAndState(ctx, &api.QueryLatestEventsAndStateRequest{
+		RoomID:       roomID,
+		StateToFetch: []gomatrixserverlib.StateKeyTuple{},
+	}, &stateRes); err != nil {
+		util.GetLogger(ctx).WithError(err).Error("queryAPI.QueryLatestEventsAndState failed")
+		return jsonerror.InternalServerError()
+	}
+
+	// Look at the room state and see if we have a history visibility event
+	// that marks the room as world-readable. If we don't then we assume that
+	// the room is not world-readable.
+	for _, ev := range stateRes.StateEvents {
+		if ev.Type() == gomatrixserverlib.MRoomHistoryVisibility {
+			content := map[string]string{}
+			if err := json.Unmarshal(ev.Content(), &content); err != nil {
+				util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for history visibility failed")
+				return jsonerror.InternalServerError()
+			}
+			if visibility, ok := content["history_visibility"]; ok {
+				worldReadable = visibility == "world_readable"
+				break
+			}
+		}
+	}
+
+	// If the room isn't world-readable then we will instead try to find out
+	// the state of the room based on the user's membership. If the user is
+	// in the room then we'll want the latest state. If the user has never
+	// been in the room and the room isn't world-readable, then we won't
+	// return any state. If the user was in the room previously but is no
+	// longer then we will return the state at the time that the user left.
+	// membershipRes will only be populated if the room is not world-readable.
+	var membershipRes api.QueryMembershipForUserResponse
+	if !worldReadable {
+		// The room isn't world-readable so try to work out based on the
+		// user's membership if we want the latest state or not.
+		err := rsAPI.QueryMembershipForUser(ctx, &api.QueryMembershipForUserRequest{
+			RoomID: roomID,
+			UserID: device.UserID,
+		}, &membershipRes)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
+			return jsonerror.InternalServerError()
+		}
+		// If the user has never been in the room then stop at this point.
+		// We won't tell the user about a room they have never joined.
+		if !membershipRes.HasBeenInRoom {
+			return util.JSONResponse{
+				Code: http.StatusForbidden,
+				JSON: jsonerror.Forbidden(fmt.Sprintf("Unknown room %q or user %q has never joined this room", roomID, device.UserID)),
+			}
+		}
+		// Otherwise, if the user has been in the room, whether or not we
+		// give them the latest state will depend on if they are *still* in
+		// the room.
+		wantLatestState = membershipRes.IsInRoom
+	} else {
+		// The room is world-readable so the user join state is irrelevant,
+		// just get the latest room state instead.
+		wantLatestState = true
+	}
+
+	util.GetLogger(ctx).WithFields(log.Fields{
+		"roomID":         roomID,
+		"state_at_event": !wantLatestState,
+	}).Info("Fetching all state")
+
+	stateEvents := []gomatrixserverlib.ClientEvent{}
+	if wantLatestState {
+		// If we are happy to use the latest state, either because the user is
+		// still in the room, or because the room is world-readable, then just
+		// use the result of the previous QueryLatestEventsAndState response
+		// to find the state event, if provided.
+		for _, ev := range stateRes.StateEvents {
+			stateEvents = append(
+				stateEvents,
+				gomatrixserverlib.HeaderedToClientEvent(ev, gomatrixserverlib.FormatAll),
+			)
+		}
+	} else {
+		// Otherwise, take the event ID of their leave event and work out what
+		// the state of the room was before that event.
+		var stateAfterRes api.QueryStateAfterEventsResponse
+		err := rsAPI.QueryStateAfterEvents(ctx, &api.QueryStateAfterEventsRequest{
+			RoomID:       roomID,
+			PrevEventIDs: []string{membershipRes.EventID},
+			StateToFetch: []gomatrixserverlib.StateKeyTuple{},
+		}, &stateAfterRes)
+		if err != nil {
+			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
+			return jsonerror.InternalServerError()
+		}
+		for _, ev := range stateRes.StateEvents {
+			stateEvents = append(
+				stateEvents,
+				gomatrixserverlib.HeaderedToClientEvent(ev, gomatrixserverlib.FormatAll),
+			)
+		}
+	}
+
+	// Return the results to the requestor.
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: stateEvents,
+	}
+}
+
+// OnIncomingStateTypeRequest is called when a client makes a
+// /rooms/{roomID}/state/{type}/{statekey} request. It will look in current
+// state to see if there is an event with that type and state key, if there
+// is then (by default) we return the content, otherwise a 404.
+// If eventFormat=true, sends the whole event else just the content.
 // nolint:gocyclo
 func OnIncomingStateTypeRequest(
 	ctx context.Context, device *userapi.Device, rsAPI api.RoomserverInternalAPI,
-	roomID, evType, stateKey string,
+	roomID, evType, stateKey string, eventFormat bool,
 ) util.JSONResponse {
 	var worldReadable bool
 	var wantLatestState bool
-	wantAllState := evType == ""
-
-	// Work out the state to fetch. If we want the entire room state then
-	// we leave the stateToFetch empty. Otherwise we specify what we want.
-	stateToFetch := []gomatrixserverlib.StateKeyTuple{}
-	if !wantAllState {
-		stateToFetch = append(stateToFetch, gomatrixserverlib.StateKeyTuple{
-			EventType: evType,
-			StateKey:  stateKey,
-		})
-	}
 
 	// Always fetch visibility so that we can work out whether to show
 	// the latest events or the last event from when the user was joined.
 	// Then include the requested event type and state key, assuming it
 	// isn't for the same.
-	stateToFetchIncVisibility := stateToFetch
+	stateToFetch := []gomatrixserverlib.StateKeyTuple{
-	if !wantAllState && evType != gomatrixserverlib.MRoomHistoryVisibility && stateKey != "" {
+		{
-		stateToFetchIncVisibility = append(
+			EventType: evType,
-			stateToFetchIncVisibility,
+			StateKey:  stateKey,
-			gomatrixserverlib.StateKeyTuple{
+		},
-				EventType: gomatrixserverlib.MRoomHistoryVisibility,
+	}
-				StateKey:  "",
+	if evType != gomatrixserverlib.MRoomHistoryVisibility && stateKey != "" {
-			},
+		stateToFetch = append(stateToFetch, gomatrixserverlib.StateKeyTuple{
-		)
+			EventType: gomatrixserverlib.MRoomHistoryVisibility,
+			StateKey:  "",
+		})
 	}
 
 	// First of all, get the latest state of the room. We need to do this
@@ -77,7 +192,7 @@ func OnIncomingStateTypeRequest(
 	stateRes := api.QueryLatestEventsAndStateResponse{}
 	if err := rsAPI.QueryLatestEventsAndState(ctx, &api.QueryLatestEventsAndStateRequest{
 		RoomID:       roomID,
-		StateToFetch: stateToFetchIncVisibility,
+		StateToFetch: stateToFetch,
 	}, &stateRes); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("queryAPI.QueryLatestEventsAndState failed")
 		return jsonerror.InternalServerError()
@@ -144,7 +259,7 @@ func OnIncomingStateTypeRequest(
 		"state_at_event": !wantLatestState,
 	}).Info("Fetching state")
 
-	var events []*gomatrixserverlib.HeaderedEvent
+	var event *gomatrixserverlib.HeaderedEvent
 	if wantLatestState {
 		// If we are happy to use the latest state, either because the user is
 		// still in the room, or because the room is world-readable, then just
@@ -152,7 +267,7 @@ func OnIncomingStateTypeRequest(
 		// to find the state event, if provided.
 		for _, ev := range stateRes.StateEvents {
 			if ev.Type() == evType && ev.StateKeyEquals(stateKey) {
-				events = append(events, &ev)
+				event = &ev
 				break
 			}
 		}
@@ -163,36 +278,42 @@ func OnIncomingStateTypeRequest(
 		err := rsAPI.QueryStateAfterEvents(ctx, &api.QueryStateAfterEventsRequest{
 			RoomID:       roomID,
 			PrevEventIDs: []string{membershipRes.EventID},
-			StateToFetch: stateToFetch,
+			StateToFetch: []gomatrixserverlib.StateKeyTuple{
+				{
+					EventType: evType,
+					StateKey:  stateKey,
+				},
+			},
 		}, &stateAfterRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
 			return jsonerror.InternalServerError()
 		}
 		if len(stateAfterRes.StateEvents) > 0 {
-			events = append(events, &stateAfterRes.StateEvents[0])
+			event = &stateAfterRes.StateEvents[0]
 		}
 	}
 
 	// If there was no event found that matches all of the above criteria then
 	// return an error.
-	if !wantAllState && len(events) == 0 {
+	if event == nil {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
 			JSON: jsonerror.NotFound(fmt.Sprintf("Cannot find state event for %q", evType)),
 		}
 	}
 
-	// Turn the events into client events.
+	stateEvent := stateEventInStateResp{
-	var res []gomatrixserverlib.ClientEvent
+		ClientEvent: gomatrixserverlib.HeaderedToClientEvent(*event, gomatrixserverlib.FormatAll),
-	for _, event := range events {
+	}
-		res = append(
+
-			res,
+	var res interface{}
-			gomatrixserverlib.HeaderedToClientEvent(*event, gomatrixserverlib.FormatAll),
+	if eventFormat {
-		)
+		res = stateEvent
+	} else {
+		res = stateEvent.Content
 	}
 
-	// Return the client events.
 	return util.JSONResponse{
 		Code: http.StatusOK,
 		JSON: res,