Poll model - validate end events (#3072)

* first cut poll model

* process incoming poll relations

* allow alt event types in relations model

* allow alt event types in relations model

* remove unneccesary checks on remove relation

* comment

* Revert "allow alt event types in relations model"

This reverts commit e578d84464.

* Revert "Revert "allow alt event types in relations model""

This reverts commit 515db7a8bc.

* basic handling for new poll relations

* tests

* test room.processPollEvents

* join processBeaconEvents and poll events in client

* tidy and set 23 copyrights

* use rooms instance of matrixClient

* tidy

* more copyright

* simplify processPollEvent code

* throw when poll start event has no roomId

* updates for events-sdk move

* more type changes for events-sdk changes

* validate poll end event senders

* reformatted copyright

* undo more comment reformatting

* fix poll end validation logic to allow poll creator to end poll regardless of redaction

* Update src/models/poll.ts

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

* correct creator == sender validationin poll end

---------

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

spec/test-utils/client.ts

@@ -60,6 +60,7 @@ export const getMockClientWithEventEmitter = (
  */
 export const mockClientMethodsUser = (userId = "@alice:domain") => ({
     getUserId: jest.fn().mockReturnValue(userId),
+    getSafeUserId: jest.fn().mockReturnValue(userId),
     getUser: jest.fn().mockReturnValue(new User(userId)),
     isGuest: jest.fn().mockReturnValue(false),
     mxcUrlToHttp: jest.fn().mockReturnValue("mock-mxcUrlToHttp"),

spec/unit/models/poll.spec.ts

@@ -14,26 +14,31 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { IEvent, MatrixEvent, PollEvent } from "../../../src";
+import { IEvent, MatrixEvent, PollEvent, Room } from "../../../src";
 import { REFERENCE_RELATION } from "../../../src/@types/extensible_events";
 import { M_POLL_END, M_POLL_KIND_DISCLOSED, M_POLL_RESPONSE } from "../../../src/@types/polls";
 import { PollStartEvent } from "../../../src/extensible_events_v1/PollStartEvent";
 import { Poll } from "../../../src/models/poll";
-import { getMockClientWithEventEmitter } from "../../test-utils/client";
+import { getMockClientWithEventEmitter, mockClientMethodsUser } from "../../test-utils/client";
 
 jest.useFakeTimers();
 
 describe("Poll", () => {
+    const userId = "@alice:server.org";
     const mockClient = getMockClientWithEventEmitter({
+        ...mockClientMethodsUser(userId),
         relations: jest.fn(),
     });
     const roomId = "!room:server";
+    const room = new Room(roomId, mockClient, userId);
+    const maySendRedactionForEventSpy = jest.spyOn(room.currentState, "maySendRedactionForEvent");
     // 14.03.2022 16:15
     const now = 1647270879403;
 
     const basePollStartEvent = new MatrixEvent({
         ...PollStartEvent.from("What?", ["a", "b"], M_POLL_KIND_DISCLOSED.name).serialize(),
         room_id: roomId,
+        sender: userId,
     });
     basePollStartEvent.event.event_id = "$12345";
 
@@ -42,6 +47,8 @@ describe("Poll", () => {
         jest.setSystemTime(now);
 
         mockClient.relations.mockResolvedValue({ events: [] });
+
+        maySendRedactionForEventSpy.mockClear().mockReturnValue(true);
     });
 
     let eventId = 1;
@@ -62,7 +69,7 @@ describe("Poll", () => {
     };
 
     it("initialises with root event", () => {
-        const poll = new Poll(basePollStartEvent, mockClient);
+        const poll = new Poll(basePollStartEvent, mockClient, room);
         expect(poll.roomId).toEqual(roomId);
         expect(poll.pollId).toEqual(basePollStartEvent.getId());
         expect(poll.pollEvent).toEqual(basePollStartEvent.unstableExtensibleEvent);
@@ -73,7 +80,7 @@ describe("Poll", () => {
         const pollStartEvent = new MatrixEvent(
             PollStartEvent.from("What?", ["a", "b"], M_POLL_KIND_DISCLOSED.name).serialize(),
         );
-        expect(() => new Poll(pollStartEvent, mockClient)).toThrowError("Invalid poll start event.");
+        expect(() => new Poll(pollStartEvent, mockClient, room)).toThrowError("Invalid poll start event.");
     });
 
     it("throws when poll start has no event id", () => {
@@ -81,12 +88,12 @@ describe("Poll", () => {
             ...PollStartEvent.from("What?", ["a", "b"], M_POLL_KIND_DISCLOSED.name).serialize(),
             room_id: roomId,
         });
-        expect(() => new Poll(pollStartEvent, mockClient)).toThrowError("Invalid poll start event.");
+        expect(() => new Poll(pollStartEvent, mockClient, room)).toThrowError("Invalid poll start event.");
     });
 
     describe("fetching responses", () => {
         it("calls relations api and emits", async () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             const emitSpy = jest.spyOn(poll, "emit");
             const responses = await poll.getResponses();
             expect(mockClient.relations).toHaveBeenCalledWith(roomId, basePollStartEvent.getId(), "m.reference");
@@ -94,7 +101,7 @@ describe("Poll", () => {
         });
 
         it("returns existing responses object after initial fetch", async () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             const responses = await poll.getResponses();
             const responses2 = await poll.getResponses();
             // only fetched relations once
@@ -104,7 +111,7 @@ describe("Poll", () => {
         });
 
         it("waits for existing relations request to finish when getting responses", async () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             const firstResponsePromise = poll.getResponses();
             const secondResponsePromise = poll.getResponses();
             await firstResponsePromise;
@@ -121,14 +128,14 @@ describe("Poll", () => {
             mockClient.relations.mockResolvedValue({
                 events: [replyEvent, stableResponseEvent, unstableResponseEvent],
             });
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             const responses = await poll.getResponses();
             expect(responses.getRelations()).toEqual([stableResponseEvent, unstableResponseEvent]);
         });
 
         describe("with poll end event", () => {
-            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable! });
+            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: "@bob@server.org" });
-            const unstablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.unstable! });
+            const unstablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.unstable!, sender: "@bob@server.org" });
             const responseEventBeforeEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now - 1000);
             const responseEventAtEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now);
             const responseEventAfterEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now + 1000);
@@ -140,10 +147,43 @@ describe("Poll", () => {
             });
 
             it("sets poll end event with stable event type", async () => {
-                const poll = new Poll(basePollStartEvent, mockClient);
+                const poll = new Poll(basePollStartEvent, mockClient, room);
                 jest.spyOn(poll, "emit");
                 await poll.getResponses();
 
+                expect(maySendRedactionForEventSpy).toHaveBeenCalledWith(basePollStartEvent, "@bob@server.org");
+                expect(poll.isEnded).toBe(true);
+                expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
+            });
+
+            it("does not set poll end event when sent by a user without redaction rights", async () => {
+                const poll = new Poll(basePollStartEvent, mockClient, room);
+                maySendRedactionForEventSpy.mockReturnValue(false);
+                jest.spyOn(poll, "emit");
+                await poll.getResponses();
+
+                expect(maySendRedactionForEventSpy).toHaveBeenCalledWith(basePollStartEvent, "@bob@server.org");
+                expect(poll.isEnded).toBe(false);
+                expect(poll.emit).not.toHaveBeenCalledWith(PollEvent.End);
+            });
+
+            it("sets poll end event when endevent sender also created the poll, but does not have redaction rights", async () => {
+                const pollStartEvent = new MatrixEvent({
+                    ...PollStartEvent.from("What?", ["a", "b"], M_POLL_KIND_DISCLOSED.name).serialize(),
+                    room_id: roomId,
+                    sender: "@bob:domain.org",
+                });
+                pollStartEvent.event.event_id = "$6789";
+                const poll = new Poll(pollStartEvent, mockClient, room);
+                const pollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: "@bob:domain.org" });
+                mockClient.relations.mockResolvedValue({
+                    events: [pollEndEvent],
+                });
+                maySendRedactionForEventSpy.mockReturnValue(false);
+                jest.spyOn(poll, "emit");
+                await poll.getResponses();
+
+                expect(maySendRedactionForEventSpy).not.toHaveBeenCalled();
                 expect(poll.isEnded).toBe(true);
                 expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
             });
@@ -152,7 +192,7 @@ describe("Poll", () => {
                 mockClient.relations.mockResolvedValue({
                     events: [unstablePollEndEvent],
                 });
-                const poll = new Poll(basePollStartEvent, mockClient);
+                const poll = new Poll(basePollStartEvent, mockClient, room);
                 jest.spyOn(poll, "emit");
                 await poll.getResponses();
 
@@ -161,7 +201,7 @@ describe("Poll", () => {
             });
 
             it("filters out responses that were sent after poll end", async () => {
-                const poll = new Poll(basePollStartEvent, mockClient);
+                const poll = new Poll(basePollStartEvent, mockClient, room);
                 const responses = await poll.getResponses();
 
                 // just response type events
@@ -173,7 +213,7 @@ describe("Poll", () => {
 
     describe("onNewRelation()", () => {
         it("discards response if poll responses have not been initialised", () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             jest.spyOn(poll, "emit");
             const responseEvent = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now);
 
@@ -184,24 +224,107 @@ describe("Poll", () => {
         });
 
         it("sets poll end event when responses are not initialised", () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             jest.spyOn(poll, "emit");
-            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable! });
+            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: userId });
 
             poll.onNewRelation(stablePollEndEvent);
 
             expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
         });
 
+        it("does not set poll end event when sent by invalid user", async () => {
+            maySendRedactionForEventSpy.mockReturnValue(false);
+            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: "@charlie:server.org" });
+            const responseEventAfterEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now + 1000);
+            mockClient.relations.mockResolvedValue({
+                events: [responseEventAfterEnd],
+            });
+            const poll = new Poll(basePollStartEvent, mockClient, room);
+            await poll.getResponses();
+            jest.spyOn(poll, "emit");
+
+            poll.onNewRelation(stablePollEndEvent);
+
+            // didn't end, didn't refilter responses
+            expect(poll.emit).not.toHaveBeenCalled();
+            expect(poll.isEnded).toBeFalsy();
+            expect(maySendRedactionForEventSpy).toHaveBeenCalledWith(basePollStartEvent, "@charlie:server.org");
+        });
+
+        it("does not set poll end event when an earlier end event already exists", async () => {
+            const earlierPollEndEvent = makeRelatedEvent(
+                { type: M_POLL_END.stable!, sender: "@valid:server.org" },
+                now,
+            );
+            const laterPollEndEvent = makeRelatedEvent(
+                { type: M_POLL_END.stable!, sender: "@valid:server.org" },
+                now + 2000,
+            );
+
+            const poll = new Poll(basePollStartEvent, mockClient, room);
+            await poll.getResponses();
+
+            poll.onNewRelation(earlierPollEndEvent);
+
+            // first end event set correctly
+            expect(poll.isEnded).toBeTruthy();
+
+            // reset spy count
+            jest.spyOn(poll, "emit").mockClear();
+
+            poll.onNewRelation(laterPollEndEvent);
+            // didn't set new end event, didn't refilter responses
+            expect(poll.emit).not.toHaveBeenCalled();
+            expect(poll.isEnded).toBeTruthy();
+        });
+
+        it("replaces poll end event and refilters when an older end event already exists", async () => {
+            const earlierPollEndEvent = makeRelatedEvent(
+                { type: M_POLL_END.stable!, sender: "@valid:server.org" },
+                now,
+            );
+            const laterPollEndEvent = makeRelatedEvent(
+                { type: M_POLL_END.stable!, sender: "@valid:server.org" },
+                now + 2000,
+            );
+            const responseEventBeforeEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now - 1000);
+            const responseEventAtEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now);
+            const responseEventAfterEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now + 1000);
+            mockClient.relations.mockResolvedValue({
+                events: [responseEventAfterEnd, responseEventAtEnd, responseEventBeforeEnd, laterPollEndEvent],
+            });
+
+            const poll = new Poll(basePollStartEvent, mockClient, room);
+            const responses = await poll.getResponses();
+
+            // all responses have a timestamp < laterPollEndEvent
+            expect(responses.getRelations().length).toEqual(3);
+            // first end event set correctly
+            expect(poll.isEnded).toBeTruthy();
+
+            // reset spy count
+            jest.spyOn(poll, "emit").mockClear();
+
+            // add a valid end event with earlier timestamp
+            poll.onNewRelation(earlierPollEndEvent);
+
+            // emitted new end event
+            expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
+            // filtered responses and emitted
+            expect(poll.emit).toHaveBeenCalledWith(PollEvent.Responses, responses);
+            expect(responses.getRelations()).toEqual([responseEventAtEnd, responseEventBeforeEnd]);
+        });
+
         it("sets poll end event and refilters responses based on timestamp", async () => {
-            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable! });
+            const stablePollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: userId });
             const responseEventBeforeEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now - 1000);
             const responseEventAtEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now);
             const responseEventAfterEnd = makeRelatedEvent({ type: M_POLL_RESPONSE.name }, now + 1000);
             mockClient.relations.mockResolvedValue({
                 events: [responseEventAfterEnd, responseEventAtEnd, responseEventBeforeEnd],
             });
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             const responses = await poll.getResponses();
             jest.spyOn(poll, "emit");
 
@@ -216,7 +339,7 @@ describe("Poll", () => {
         });
 
         it("filters out irrelevant relations", async () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             // init responses
             const responses = await poll.getResponses();
             jest.spyOn(poll, "emit");
@@ -230,7 +353,7 @@ describe("Poll", () => {
         });
 
         it("adds poll response relations to responses", async () => {
-            const poll = new Poll(basePollStartEvent, mockClient);
+            const poll = new Poll(basePollStartEvent, mockClient, room);
             // init responses
             const responses = await poll.getResponses();
             jest.spyOn(poll, "emit");

src/models/poll.ts

@@ -18,6 +18,7 @@ import { M_POLL_END, M_POLL_RESPONSE, PollStartEvent } from "../@types/polls";
 import { MatrixClient } from "../client";
 import { MatrixEvent } from "./event";
 import { Relations } from "./relations";
+import { Room } from "./room";
 import { TypedEventEmitter } from "./typed-event-emitter";
 
 export enum PollEvent {
@@ -64,13 +65,12 @@ export class Poll extends TypedEventEmitter<Exclude<PollEvent, PollEvent.New>, P
     private responses: null | Relations = null;
     private endEvent: MatrixEvent | undefined;
 
-    public constructor(private rootEvent: MatrixEvent, private matrixClient: MatrixClient) {
+    public constructor(private rootEvent: MatrixEvent, private matrixClient: MatrixClient, private room: Room) {
         super();
         if (!this.rootEvent.getRoomId() || !this.rootEvent.getId()) {
             throw new Error("Invalid poll start event.");
         }
         this.roomId = this.rootEvent.getRoomId()!;
-        // @TODO(kerrya) proper way to do this?
         this.pollEvent = this.rootEvent.unstableExtensibleEvent as unknown as PollStartEvent;
     }
 
@@ -101,7 +101,7 @@ export class Poll extends TypedEventEmitter<Exclude<PollEvent, PollEvent.New>, P
      * @returns void
      */
     public onNewRelation(event: MatrixEvent): void {
-        if (M_POLL_END.matches(event.getType())) {
+        if (M_POLL_END.matches(event.getType()) && this.validateEndEvent(event)) {
             this.endEvent = event;
             this.refilterResponsesOnEnd();
             this.emit(PollEvent.End);
@@ -136,7 +136,8 @@ export class Poll extends TypedEventEmitter<Exclude<PollEvent, PollEvent.New>, P
             M_POLL_RESPONSE.altName!,
         ]);
 
-        const pollEndEvent = allRelations.events.find((event) => M_POLL_END.matches(event.getType()));
+        const potentialEndEvent = allRelations.events.find((event) => M_POLL_END.matches(event.getType()));
+        const pollEndEvent = this.validateEndEvent(potentialEndEvent) ? potentialEndEvent : undefined;
         const pollCloseTimestamp = pollEndEvent?.getTs() || Number.MAX_SAFE_INTEGER;
 
         const { responseEvents } = filterResponseRelations(allRelations.events, pollCloseTimestamp);
@@ -172,4 +173,30 @@ export class Poll extends TypedEventEmitter<Exclude<PollEvent, PollEvent.New>, P
 
         this.emit(PollEvent.Responses, this.responses);
     }
+
+    private validateEndEvent(endEvent?: MatrixEvent): boolean {
+        if (!endEvent) {
+            return false;
+        }
+        /**
+         * Repeated end events are ignored -
+         * only the first (valid) closure event by origin_server_ts is counted.
+         */
+        if (this.endEvent && this.endEvent.getTs() < endEvent.getTs()) {
+            return false;
+        }
+
+        /**
+         * MSC3381
+         * If a m.poll.end event is received from someone other than the poll creator or user with permission to redact
+         * others' messages in the room, the event must be ignored by clients due to being invalid.
+         */
+        const roomCurrentState = this.room.currentState;
+        const endEventSender = endEvent.getSender();
+        return (
+            !!endEventSender &&
+            (endEventSender === this.rootEvent.getSender() ||
+                roomCurrentState.maySendRedactionForEvent(this.rootEvent, endEventSender))
+        );
+    }
 }

src/models/room.ts

@@ -1897,7 +1897,7 @@ export class Room extends ReadReceipt<RoomEmittedEvents, RoomEventHandlerMap> {
         const processPollStartEvent = (event: MatrixEvent): void => {
             if (!M_POLL_START.matches(event.getType())) return;
             try {
-                const poll = new Poll(event, this.client);
+                const poll = new Poll(event, this.client, this);
                 this.polls.set(event.getId()!, poll);
                 this.emit(PollEvent.New, poll);
             } catch {}