Add query API for listing active invites (#196)

* Add query API for listing active invites

This lists the invites for a user in a room that could be used to
join the room over federation.

* s/Lookup/Look up/

* Fix implements comments

src/github.com/matrix-org/dendrite/roomserver/api/query.go

@@ -117,6 +117,23 @@ type QueryMembershipsForRoomResponse struct {
 	HasBeenInRoom bool `json:"has_been_in_room"`
 }
 
+// QueryInvitesForUserRequest is a request to QueryInvitesForUser
+type QueryInvitesForUserRequest struct {
+	// The room ID to look up invites in.
+	RoomID string `json:"room_id"`
+	// The User ID to look up invites for.
+	TargetUserID string `json:"target_user_id"`
+}
+
+// QueryInvitesForUserResponse is a response to QueryInvitesForUser
+// This is used when accepting an invite or rejecting a invite to tell which
+// remote matrix servers to contact.
+type QueryInvitesForUserResponse struct {
+	// A list of matrix user IDs for each sender of an active invite targeting
+	// the requested user ID.
+	InviteSenderUserIDs []string `json:"invite_sender_user_ids"`
+}
+
 // RoomserverQueryAPI is used to query information from the room server.
 type RoomserverQueryAPI interface {
 	// Query the latest events and state for a room from the room server.
@@ -142,6 +159,12 @@ type RoomserverQueryAPI interface {
 		request *QueryMembershipsForRoomRequest,
 		response *QueryMembershipsForRoomResponse,
 	) error
+
+	// Query a list of invite event senders for a user in a room.
+	QueryInvitesForUser(
+		request *QueryInvitesForUserRequest,
+		response *QueryInvitesForUserResponse,
+	) error
 }
 
 // RoomserverQueryLatestEventsAndStatePath is the HTTP path for the QueryLatestEventsAndState API.
@@ -156,6 +179,9 @@ const RoomserverQueryEventsByIDPath = "/api/roomserver/queryEventsByID"
 // RoomserverQueryMembershipsForRoomPath is the HTTP path for the QueryMembershipsForRoom API
 const RoomserverQueryMembershipsForRoomPath = "/api/roomserver/queryMembershipsForRoom"
 
+// RoomserverQueryInvitesForUserPath is the HTTP path for the QueryInvitesForUser API
+const RoomserverQueryInvitesForUserPath = "/api/roomserver/queryInvitesForUser"
+
 // NewRoomserverQueryAPIHTTP creates a RoomserverQueryAPI implemented by talking to a HTTP POST API.
 // If httpClient is nil then it uses the http.DefaultClient
 func NewRoomserverQueryAPIHTTP(roomserverURL string, httpClient *http.Client) RoomserverQueryAPI {
@@ -206,6 +232,15 @@ func (h *httpRoomserverQueryAPI) QueryMembershipsForRoom(
 	return postJSON(h.httpClient, apiURL, request, response)
 }
 
+// QueryInvitesForUser implements RoomserverQueryAPI
+func (h *httpRoomserverQueryAPI) QueryInvitesForUser(
+	request *QueryInvitesForUserRequest,
+	response *QueryInvitesForUserResponse,
+) error {
+	apiURL := h.roomserverURL + RoomserverQueryInvitesForUserPath
+	return postJSON(h.httpClient, apiURL, request, response)
+}
+
 func postJSON(httpClient *http.Client, apiURL string, request, response interface{}) error {
 	jsonBytes, err := json.Marshal(request)
 	if err != nil {

src/github.com/matrix-org/dendrite/roomserver/query/query.go

@@ -40,18 +40,6 @@ type RoomserverQueryAPIDatabase interface {
 	// Look up the numeric IDs for a list of events.
 	// Returns an error if there was a problem talking to the database.
 	EventNIDs(eventIDs []string) (map[string]types.EventNID, error)
-	// Save a given room alias with the room ID it refers to.
-	// Returns an error if there was a problem talking to the database.
-	SetRoomAlias(alias string, roomID string) error
-	// Lookup the room ID a given alias refers to.
-	// Returns an error if there was a problem talking to the database.
-	GetRoomIDFromAlias(alias string) (string, error)
-	// Lookup all aliases referring to a given room ID.
-	// Returns an error if there was a problem talking to the database.
-	GetAliasesFromRoomID(roomID string) ([]string, error)
-	// Remove a given room alias.
-	// Returns an error if there was a problem talking to the database.
-	RemoveRoomAlias(alias string) error
 	// Look up the join events for all members in a room as requested by a given
 	// user. If the user is currently in the room, returns the room's current
 	// members, if not returns an empty array (TODO: Fix it)
@@ -59,6 +47,13 @@ type RoomserverQueryAPIDatabase interface {
 	// returns nil.
 	// If there was an issue retrieving the events, returns an error.
 	GetMembershipEvents(roomNID types.RoomNID, requestSenderUserID string) (events []types.Event, err error)
+	// Look up the active invites targeting a user in a room and return the
+	// numeric state key IDs for the user IDs who sent them.
+	// Returns an error if there was a problem talking to the database.
+	GetInvitesForUser(roomNID types.RoomNID, targetUserNID types.EventStateKeyNID) (senderUserNIDs []types.EventStateKeyNID, err error)
+	// Look up the string event state keys for a list of numeric event state keys
+	// Returns an error if there was a problem talking to the database.
+	EventStateKeys([]types.EventStateKeyNID) (map[types.EventStateKeyNID]string, error)
 }
 
 // RoomserverQueryAPI is an implementation of api.RoomserverQueryAPI
@@ -220,6 +215,39 @@ func (r *RoomserverQueryAPI) QueryMembershipsForRoom(
 	return nil
 }
 
+// QueryInvitesForUser implements api.RoomserverQueryAPI
+func (r *RoomserverQueryAPI) QueryInvitesForUser(
+	request *api.QueryInvitesForUserRequest,
+	response *api.QueryInvitesForUserResponse,
+) error {
+	roomNID, err := r.DB.RoomNID(request.RoomID)
+	if err != nil {
+		return err
+	}
+
+	targetUserNIDs, err := r.DB.EventStateKeyNIDs([]string{request.TargetUserID})
+	if err != nil {
+		return err
+	}
+	targetUserNID := targetUserNIDs[request.TargetUserID]
+
+	senderUserNIDs, err := r.DB.GetInvitesForUser(roomNID, targetUserNID)
+	if err != nil {
+		return err
+	}
+
+	senderUserIDs, err := r.DB.EventStateKeys(senderUserNIDs)
+	if err != nil {
+		return err
+	}
+
+	for _, senderUserID := range senderUserIDs {
+		response.InviteSenderUserIDs = append(response.InviteSenderUserIDs, senderUserID)
+	}
+
+	return nil
+}
+
 // SetupHTTP adds the RoomserverQueryAPI handlers to the http.ServeMux.
 func (r *RoomserverQueryAPI) SetupHTTP(servMux *http.ServeMux) {
 	servMux.Handle(
@@ -278,4 +306,18 @@ func (r *RoomserverQueryAPI) SetupHTTP(servMux *http.ServeMux) {
 			return util.JSONResponse{Code: 200, JSON: &response}
 		}),
 	)
+	servMux.Handle(
+		api.RoomserverQueryInvitesForUserPath,
+		common.MakeAPI("queryInvitesForUser", func(req *http.Request) util.JSONResponse {
+			var request api.QueryInvitesForUserRequest
+			var response api.QueryInvitesForUserResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.ErrorResponse(err)
+			}
+			if err := r.QueryInvitesForUser(&request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: 200, JSON: &response}
+		}),
+	)
 }

src/github.com/matrix-org/dendrite/roomserver/storage/storage.go

@@ -161,7 +161,12 @@ func (d *Database) EventStateKeyNIDs(eventStateKeys []string) (map[string]types.
 	return d.statements.bulkSelectEventStateKeyNID(eventStateKeys)
 }
 
-// EventNIDs implements query.RoomQueryDatabase
+// EventStateKeys implements query.RoomserverQueryAPIDatabase
+func (d *Database) EventStateKeys(eventStateKeyNIDs []types.EventStateKeyNID) (map[types.EventStateKeyNID]string, error) {
+	return d.statements.bulkSelectEventStateKey(eventStateKeyNIDs)
+}
+
+// EventNIDs implements query.RoomserverQueryAPIDatabase
 func (d *Database) EventNIDs(eventIDs []string) (map[string]types.EventNID, error) {
 	return d.statements.bulkSelectEventNID(eventIDs)
 }
@@ -336,7 +341,7 @@ func (d *Database) RoomNID(roomID string) (types.RoomNID, error) {
 	return roomNID, err
 }
 
-// LatestEventIDs implements query.RoomserverQueryAPIDB
+// LatestEventIDs implements query.RoomserverQueryAPIDatabase
 func (d *Database) LatestEventIDs(roomNID types.RoomNID) ([]gomatrixserverlib.EventReference, types.StateSnapshotNID, int64, error) {
 	eventNIDs, currentStateSnapshotNID, err := d.statements.selectLatestEventNIDs(roomNID)
 	if err != nil {
@@ -353,6 +358,13 @@ func (d *Database) LatestEventIDs(roomNID types.RoomNID) ([]gomatrixserverlib.Ev
 	return references, currentStateSnapshotNID, depth, nil
 }
 
+// GetInvitesForUser implements query.RoomserverQueryAPIDatabase
+func (d *Database) GetInvitesForUser(
+	roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
+) (senderUserIDs []types.EventStateKeyNID, err error) {
+	return d.statements.selectInviteActiveForUserInRoom(targetUserNID, roomNID)
+}
+
 // SetRoomAlias implements alias.RoomserverAliasAPIDB
 func (d *Database) SetRoomAlias(alias string, roomID string) error {
 	return d.statements.insertRoomAlias(alias, roomID)