Emit an event when the client receives TURN servers (#2529)

* Emit an event when the client receives TURN servers

* Add tests

* Fix lints

spec/unit/matrix-client.spec.ts

@@ -14,8 +14,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+import { mocked } from "jest-mock";
+
 import { logger } from "../../src/logger";
-import { MatrixClient } from "../../src/client";
+import { MatrixClient, ClientEvent } from "../../src/client";
 import { Filter } from "../../src/filter";
 import { DEFAULT_TREE_POWER_LEVELS_TEMPLATE } from "../../src/models/MSC3089TreeSpace";
 import {
@@ -35,10 +37,16 @@ import * as testUtils from "../test-utils/test-utils";
 import { makeBeaconInfoContent } from "../../src/content-helpers";
 import { M_BEACON_INFO } from "../../src/@types/beacon";
 import { ContentHelpers, Room } from "../../src";
+import { supportsMatrixCall } from "../../src/webrtc/call";
 import { makeBeaconEvent } from "../test-utils/beacon";
 
 jest.useFakeTimers();
 
+jest.mock("../../src/webrtc/call", () => ({
+    ...jest.requireActual("../../src/webrtc/call"),
+    supportsMatrixCall: jest.fn(() => false),
+}));
+
 describe("MatrixClient", function() {
     const userId = "@alice:bar";
     const identityServerUrl = "https://identity.server";
@@ -160,6 +168,24 @@ describe("MatrixClient", function() {
         return new Promise(() => {});
     }
 
+    function makeClient() {
+        client = new MatrixClient({
+            baseUrl: "https://my.home.server",
+            idBaseUrl: identityServerUrl,
+            accessToken: "my.access.token",
+            request: function() {} as any, // NOP
+            store: store,
+            scheduler: scheduler,
+            userId: userId,
+        });
+        // FIXME: We shouldn't be yanking http like this.
+        client.http = [
+            "authedRequest", "getContentUri", "request", "uploadContent",
+        ].reduce((r, k) => { r[k] = jest.fn(); return r; }, {});
+        client.http.authedRequest.mockImplementation(httpReq);
+        client.http.request.mockImplementation(httpReq);
+    }
+
     beforeEach(function() {
         scheduler = [
             "getQueueForEvent", "queueEvent", "removeEventFromQueue",
@@ -177,21 +203,7 @@ describe("MatrixClient", function() {
         store.getClientOptions = jest.fn().mockReturnValue(Promise.resolve(null));
         store.storeClientOptions = jest.fn().mockReturnValue(Promise.resolve(null));
         store.isNewlyCreated = jest.fn().mockReturnValue(Promise.resolve(true));
-        client = new MatrixClient({
+        makeClient();
-            baseUrl: "https://my.home.server",
-            idBaseUrl: identityServerUrl,
-            accessToken: "my.access.token",
-            request: function() {} as any, // NOP
-            store: store,
-            scheduler: scheduler,
-            userId: userId,
-        });
-        // FIXME: We shouldn't be yanking http like this.
-        client.http = [
-            "authedRequest", "getContentUri", "request", "uploadContent",
-        ].reduce((r, k) => { r[k] = jest.fn(); return r; }, {});
-        client.http.authedRequest.mockImplementation(httpReq);
-        client.http.request.mockImplementation(httpReq);
 
         // set reasonable working defaults
         acceptKeepalives = true;
@@ -1299,6 +1311,93 @@ describe("MatrixClient", function() {
         });
     });
 
+    describe("pollingTurnServers", () => {
+        afterEach(() => {
+            mocked(supportsMatrixCall).mockReset();
+        });
+
+        it("is false if the client isn't started", () => {
+            expect(client.clientRunning).toBe(false);
+            expect(client.pollingTurnServers).toBe(false);
+        });
+
+        it("is false if VoIP is not supported", async () => {
+            mocked(supportsMatrixCall).mockReturnValue(false);
+            makeClient(); // create the client a second time so it picks up the supportsMatrixCall mock
+            await client.startClient();
+            expect(client.pollingTurnServers).toBe(false);
+        });
+
+        it("is true if VoIP is supported", async () => {
+            mocked(supportsMatrixCall).mockReturnValue(true);
+            makeClient(); // create the client a second time so it picks up the supportsMatrixCall mock
+            await client.startClient();
+            expect(client.pollingTurnServers).toBe(true);
+        });
+    });
+
+    describe("checkTurnServers", () => {
+        beforeAll(() => {
+            mocked(supportsMatrixCall).mockReturnValue(true);
+        });
+
+        beforeEach(() => {
+            makeClient(); // create the client a second time so it picks up the supportsMatrixCall mock
+        });
+
+        afterAll(() => {
+            mocked(supportsMatrixCall).mockReset();
+        });
+
+        it("emits an event when new TURN creds are found", async () => {
+            const turnServer = {
+                uris: [
+                    "turn:turn.example.com:3478?transport=udp",
+                    "turn:10.20.30.40:3478?transport=tcp",
+                    "turns:10.20.30.40:443?transport=tcp",
+                ],
+                username: "1443779631:@user:example.com",
+                password: "JlKfBy1QwLrO20385QyAtEyIv0=",
+            };
+            jest.spyOn(client, "turnServer").mockResolvedValue(turnServer);
+
+            const events: any[][] = [];
+            const onTurnServers = (...args) => events.push(args);
+            client.on(ClientEvent.TurnServers, onTurnServers);
+            expect(await client.checkTurnServers()).toBe(true);
+            client.off(ClientEvent.TurnServers, onTurnServers);
+            expect(events).toEqual([[[{
+                urls: turnServer.uris,
+                username: turnServer.username,
+                credential: turnServer.password,
+            }]]]);
+        });
+
+        it("emits an event when an error occurs", async () => {
+            const error = new Error(":(");
+            jest.spyOn(client, "turnServer").mockRejectedValue(error);
+
+            const events: any[][] = [];
+            const onTurnServersError = (...args) => events.push(args);
+            client.on(ClientEvent.TurnServersError, onTurnServersError);
+            expect(await client.checkTurnServers()).toBe(false);
+            client.off(ClientEvent.TurnServersError, onTurnServersError);
+            expect(events).toEqual([[error, false]]); // non-fatal
+        });
+
+        it("considers 403 errors fatal", async () => {
+            const error = { httpStatus: 403 };
+            jest.spyOn(client, "turnServer").mockRejectedValue(error);
+
+            const events: any[][] = [];
+            const onTurnServersError = (...args) => events.push(args);
+            client.on(ClientEvent.TurnServersError, onTurnServersError);
+            expect(await client.checkTurnServers()).toBe(false);
+            client.off(ClientEvent.TurnServersError, onTurnServersError);
+            expect(events).toEqual([[error, true]]); // fatal
+        });
+    });
+
     describe("encryptAndSendToDevices", () => {
         it("throws an error if crypto is unavailable", () => {
             client.crypto = undefined;

src/client.ts

@@ -1,5 +1,5 @@
 /*
-Copyright 2015-2021 The Matrix.org Foundation C.I.C.
+Copyright 2015-2022 The Matrix.org Foundation C.I.C.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -506,7 +506,7 @@ interface ITurnServerResponse {
     ttl: number;
 }
 
-interface ITurnServer {
+export interface ITurnServer {
     urls: string[];
     username: string;
     credential: string;
@@ -791,6 +791,8 @@ export enum ClientEvent {
     DeleteRoom = "deleteRoom",
     SyncUnexpectedError = "sync.unexpectedError",
     ClientWellKnown = "WellKnown.client",
+    TurnServers = "turnServers",
+    TurnServersError = "turnServers.error",
 }
 
 type RoomEvents = RoomEvent.Name
@@ -861,6 +863,8 @@ export type ClientEventHandlerMap = {
     [ClientEvent.DeleteRoom]: (roomId: string) => void;
     [ClientEvent.SyncUnexpectedError]: (error: Error) => void;
     [ClientEvent.ClientWellKnown]: (data: IClientWellKnown) => void;
+    [ClientEvent.TurnServers]: (servers: ITurnServer[]) => void;
+    [ClientEvent.TurnServersError]: (error: Error, fatal: boolean) => void;
 } & RoomEventHandlerMap
     & RoomStateEventHandlerMap
     & CryptoEventHandlerMap
@@ -937,7 +941,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     protected clientWellKnownPromise: Promise<IClientWellKnown>;
     protected turnServers: ITurnServer[] = [];
     protected turnServersExpiry = 0;
-    protected checkTurnServersIntervalID: ReturnType<typeof setInterval>;
+    protected checkTurnServersIntervalID: ReturnType<typeof setInterval> | null = null;
     protected exportedOlmDeviceToImport: IExportedOlmDevice;
     protected txnCtr = 0;
     protected mediaHandler = new MediaHandler(this);
@@ -1230,6 +1234,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         this.callEventHandler = null;
 
         global.clearInterval(this.checkTurnServersIntervalID);
+        this.checkTurnServersIntervalID = null;
+
         if (this.clientWellKnownIntervalID !== undefined) {
             global.clearInterval(this.clientWellKnownIntervalID);
         }
@@ -6343,6 +6349,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         return this.turnServersExpiry;
     }
 
+    public get pollingTurnServers(): boolean {
+        return this.checkTurnServersIntervalID !== null;
+    }
+
     // XXX: Intended private, used in code.
     public async checkTurnServers(): Promise<boolean> {
         if (!this.canSupportVoip) {
@@ -6370,17 +6380,21 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                     // The TTL is in seconds but we work in ms
                     this.turnServersExpiry = Date.now() + (res.ttl * 1000);
                     credentialsGood = true;
+                    this.emit(ClientEvent.TurnServers, this.turnServers);
                 }
             } catch (err) {
                 logger.error("Failed to get TURN URIs", err);
-                // If we get a 403, there's no point in looping forever.
                 if (err.httpStatus === 403) {
+                    // We got a 403, so there's no point in looping forever.
                     logger.info("TURN access unavailable for this account: stopping credentials checks");
                     if (this.checkTurnServersIntervalID !== null) global.clearInterval(this.checkTurnServersIntervalID);
                     this.checkTurnServersIntervalID = null;
+                    this.emit(ClientEvent.TurnServersError, err, true); // fatal
+                } else {
+                    // otherwise, if we failed for whatever reason, try again the next time we're called.
+                    this.emit(ClientEvent.TurnServersError, err, false); // non-fatal
                 }
             }
-            // otherwise, if we failed for whatever reason, try again the next time we're called.
         }
 
         return credentialsGood;