Merge pull request #4153 from element-hq/valere/rtc/remove_well_known_fallback

Remove .well-known transport discovery

README.md

@@ -115,30 +115,33 @@ For more details on the packages, see the
 For operating and deploying Element Call on your own server, refer to the
 [**Self-Hosting Guide**](./docs/self_hosting.md).
 
-## 🧭 MatrixRTC Backend Discovery and Selection
+## MatrixRTC Transports
 
-For proper Element Call operation each site deployment needs a MatrixRTC backend
+For proper operation of Element Call, each deployment needs to set up a
-setup as outlined in the [Self-Hosting Guide](./docs/self_hosting.md). A typical
+MatrixRTC transport in the form of a LiveKit server as outlined in the
-federated site deployment for three different sites A, B and C is depicted below.
+[Self-Hosting Guide](./docs/self_hosting.md). A typical federated site
+deployment for three different sites A, B and C is depicted below.
 
 <p align="center">
   <img src="./docs/Federated_Setup.drawio.png" alt="Element Call federated setup">
 </p>
 
-### Backend Discovery
+### Transport Discovery
 
-The MatrixRTC backend (according to
+Element Call discovers the available MatrixRTC transports (as defined by
-[MSC4143](https://github.com/matrix-org/matrix-spec-proposals/pull/4143)) is
+[MSC4519](https://github.com/matrix-org/matrix-spec-proposals/pull/4519)) by
-announced by the Matrix site's `.well-known/matrix/client` file and discovered
+hitting the `GET /_matrix/client/unstable/org.matrix.msc4143/rtc/transports`
-via the `org.matrix.msc4143.rtc_foci` key, e.g.:
+endpoint of the Client-Server API. An example response:
 
 ```json
-"org.matrix.msc4143.rtc_foci": [
+{
+  "rtc_transports": [
     {
-        "type": "livekit",
+      "type": "livekit",
-        "livekit_service_url": "https://matrix-rtc.example.com/livekit/jwt"
+      "livekit_service_url": "https://matrix-rtc.example.com/livekit/jwt"
-    },
+    }
-]
+  ]
+}
 ```
 
 where the format for MatrixRTC using LiveKit backend is defined in
@@ -149,7 +152,7 @@ via `livekit_service_url`.
 
 ### Backend Selection
 
-- Each call participant proposes their discovered MatrixRTC backend from
+- Each call participant proposes their discovered MatrixRTC transport from
   `org.matrix.msc4143.rtc_foci` in their `org.matrix.msc3401.call.member` state event.
 - For the **LiveKit** MatrixRTC backend
   ([MSC4195](https://github.com/hughns/matrix-spec-proposals/blob/hughns/matrixrtc-livekit/proposals/4195-matrixrtc-livekit.md)),
@@ -244,10 +247,9 @@ pnpm backend
 
 > [!NOTE]
 > To ensure your local development frontend functions properly, you’ll need to
-> add certificate exceptions in your browser for `https://localhost:3000`,
+> add certificate exceptions in your browser for `https://localhost:3000` and
-> `https://matrix-rtc.m.localhost/livekit/jwt/healthz` and
+> `https://matrix-rtc.m.localhost/livekit/jwt/healthz`. This can be done either
-> `https://synapse.m.localhost/.well-known/matrix/client`. This can be either
+> by adding the minimum localhost CA
-> done by adding the minimum localhost CA
 > ([./backend/dev_tls_local-ca.crt](./backend/dev_tls_local-ca.crt)) to your web
 > browser's trusted certificates or by simply copying and pasting each URL into
 > your browser’s address bar and follow the prompts to add the exception.

backend/dev_homeserver-othersite.yaml

@@ -40,6 +40,8 @@ experimental_features:
   msc4222_enabled: true
   # sticky events for MatrixRTC user state
   msc4354_enabled: true
+  # MatrixRTC
+  msc4143_enabled: true
 
 # The maximum allowed duration by which sent events can be delayed, as
 # per MSC4140. Must be a positive value if set.  Defaults to no
@@ -54,7 +56,6 @@ enable_registration_without_verification: true
 registration_shared_secret: "test_shared_secret_for_local_dev_only"
 
 report_stats: false
-serve_server_wellknown: true
 
 # Ratelimiting settings for client actions (registration, login, messaging).
 #
@@ -67,3 +68,8 @@ rc_message:
   # Currently the heart-beat is every 5 seconds which translates into a rate of 0.2s
   per_second: 0.5
   burst_count: 30
+
+matrix_rtc:
+  transports:
+    - type: livekit
+      livekit_service_url: https://matrix-rtc.othersite.m.localhost/livekit/jwt

backend/dev_homeserver.yaml

@@ -40,6 +40,8 @@ experimental_features:
   msc4222_enabled: true
   # sticky events for MatrixRTC user state
   msc4354_enabled: true
+  # MatrixRTC
+  msc4143_enabled: true
 
 # The maximum allowed duration by which sent events can be delayed, as
 # per MSC4140. Must be a positive value if set.  Defaults to no
@@ -54,7 +56,6 @@ enable_registration_without_verification: true
 registration_shared_secret: "test_shared_secret_for_local_dev_only"
 
 report_stats: false
-serve_server_wellknown: true
 
 # Ratelimiting settings for client actions (registration, login, messaging).
 #
@@ -67,3 +68,8 @@ rc_message:
   # Currently the heart-beat is every 5 seconds which translates into a rate of 0.2s
   per_second: 0.5
   burst_count: 30
+
+matrix_rtc:
+  transports:
+    - type: livekit
+      livekit_service_url: https://matrix-rtc.m.localhost/livekit/jwt

backend/dev_nginx.conf

@@ -1,4 +1,4 @@
-# Synapse reverse proxy including .well-known/matrix/client
+# Synapse reverse proxy
 # domain synapse.m.localhost
 server {
     listen                  80;
@@ -11,18 +11,6 @@ server {
     ssl_certificate         /root/ssl/cert.pem;
     ssl_certificate_key     /root/ssl/key.pem;
 
-    # well-known config adding rtc_foci backend
-    # Note well-known is currently not effective due to:
-    # https://spec.matrix.org/v1.12/client-server-api/#well-known-uri the spec
-    # says it must be at https://$server_name/... (implied port 443) Hence, we
-    # currently rely for local development environment on deprecated config.json
-    # setting for livekit_service_url
-    location /.well-known/matrix/client {
-        add_header Access-Control-Allow-Origin *;
-        return 200 '{"m.homeserver": {"base_url": "https://synapse.m.localhost"}, "org.matrix.msc4143.rtc_foci": [{"type": "livekit", "livekit_service_url": "https://matrix-rtc.m.localhost/livekit/jwt"}]}';
-        default_type application/json;
-    }
-
     # Reverse proxy for Matrix Synapse Homeserver
     # This is also required for development environment.
     # Reason: the lk-jwt-service uses the federation API for the openid token
@@ -44,7 +32,7 @@ server {
 
 }
 
-# Synapse reverse proxy including .well-known/matrix/client
+# Synapse reverse proxy
 # domain synapse.othersite.m.localhost
 server {
     listen                  80;
@@ -57,18 +45,6 @@ server {
     ssl_certificate         /root/ssl/cert.pem;
     ssl_certificate_key     /root/ssl/key.pem;
 
-    # well-known config adding rtc_foci backend
-    # Note well-known is currently not effective due to:
-    # https://spec.matrix.org/v1.12/client-server-api/#well-known-uri the spec
-    # says it must be at https://$server_name/... (implied port 443) Hence, we
-    # currently rely for local development environment on deprecated config.json
-    # setting for livekit_service_url
-    location /.well-known/matrix/client {
-        add_header Access-Control-Allow-Origin *;
-        return 200 '{"m.homeserver": {"base_url": "https://synapse.othersite.m.localhost"}, "org.matrix.msc4143.rtc_foci": [{"type": "livekit", "livekit_service_url": "https://matrix-rtc.othersite.m.localhost/livekit/jwt"}]}';
-        default_type application/json;
-    }
-
     # Reverse proxy for Matrix Synapse Homeserver
     # This is also required for development environment.
     # Reason: the lk-jwt-service uses the federation API for the openid token

backend/playwright_homeserver-othersite.yaml

@@ -40,6 +40,8 @@ experimental_features:
   msc4222_enabled: true
   # sticky events for MatrixRTC user state
   msc4354_enabled: true
+  # MatrixRTC
+  msc4143_enabled: true
 
 # The maximum allowed duration by which sent events can be delayed, as
 # per MSC4140. Must be a positive value if set.  Defaults to no
@@ -54,7 +56,6 @@ enable_registration_without_verification: true
 registration_shared_secret: "test_shared_secret_for_local_dev_only"
 
 report_stats: false
-serve_server_wellknown: true
 
 # Ratelimiting settings for client actions (registration, login, messaging).
 #
@@ -84,3 +85,8 @@ rc_login:
 rc_registration:
   per_second: 10000
   burst_count: 10000
+
+matrix_rtc:
+  transports:
+    - type: livekit
+      livekit_service_url: https://matrix-rtc.othersite.m.localhost/livekit/jwt

backend/playwright_homeserver.yaml

@@ -40,6 +40,8 @@ experimental_features:
   msc4222_enabled: true
   # sticky events for MatrixRTC user state
   msc4354_enabled: true
+  # MatrixRTC
+  msc4143_enabled: true
 
 # The maximum allowed duration by which sent events can be delayed, as
 # per MSC4140. Must be a positive value if set.  Defaults to no
@@ -54,7 +56,6 @@ enable_registration_without_verification: true
 registration_shared_secret: "test_shared_secret_for_local_dev_only"
 
 report_stats: false
-serve_server_wellknown: true
 
 # Ratelimiting settings for client actions (registration, login, messaging).
 #
@@ -84,3 +85,8 @@ rc_login:
 rc_registration:
   per_second: 10000
   burst_count: 10000
+
+matrix_rtc:
+  transports:
+    - type: livekit
+      livekit_service_url: https://matrix-rtc.m.localhost/livekit/jwt

docs/self_hosting.md

@@ -68,10 +68,10 @@ As a prerequisite for the
 make sure that your Synapse server has either a `federation` or `openid`
 [listener configured](https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#listeners).
 
-### MatrixRTC Backend
+### LiveKit backend
 
-In order to **guarantee smooth operation** of Element Call, a MatrixRTC backend is
+In order to **guarantee smooth operation** of Element Call, a dedicated LiveKit
-required for each site deployment.
+backend is required for each site deployment.
 
 ![MSC4195 compatible setup](MSC4195_setup.drawio.png)
 
@@ -165,7 +165,7 @@ Using Haproxy, you can achieve this by:
     use_backend mxrtc_auth_backend if is_mxrtc_auth matrixrtc_domain
 
 # Backend
-## MatrixRTC backend
+## LiveKit backend
 backend sfu_backend
     server livekit 127.0.0.1:7880
     http-request set-path %[path,regsub(^/livekit/sfu/,/)]
@@ -187,43 +187,22 @@ backend mxrtc_auth_backend
 
 ```
 
-#### MatrixRTC backend announcement
+#### MatrixRTC transport announcement
 
-> [!IMPORTANT]
+Enable the unstable feature flag `msc4143_enabled`, and update the
-> As defined in
+[`matrix_rtc` section](https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#matrix_rtc)
-> [MSC4143](https://github.com/matrix-org/matrix-spec-proposals/pull/4143),
+of your Synapse config file:
-> the MatrixRTC backend(s) must be announced to the client via your **Matrix site's
-> `.well-known/matrix/client`** file (e.g.
-> `example.com/.well-known/matrix/client` matching the site deployment example
-> from above). The configuration is a list of Foci configs:
 
-```json
+```yaml
-"org.matrix.msc4143.rtc_foci": [
+matrix_rtc:
-    {
+  transports:
-        "type": "livekit",
+    - type: livekit
-        "livekit_service_url": "https://matrix-rtc.example.com/livekit/jwt"
+      livekit_service_url: https://matrix-rtc.example.com/livekit/jwt
-    },
-    {
-        "type": "livekit",
-        "livekit_service_url": "https://matrix-rtc-2.example.com/livekit/jwt"
-    }
-]
 ```
 
-Make sure this file is served with the correct MIME type (`application/json`).
+The transport you specify will be made available to clients over the
-Additionally, ensure the appropriate CORS headers are set to allow web clients
+`/_matrix/client/unstable/org.matrix.msc4143/rtc/transports` endpoint as defined
-to access it across origins. For more details, refer to the
+in [MSC4143](https://github.com/matrix-org/matrix-spec-proposals/pull/4143).
-[Matrix Client-Server API: 2. Web Browser Clients](https://spec.matrix.org/latest/client-server-api/#web-browser-clients).
-
-```
-Access-Control-Allow-Origin: *
-Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS
-Access-Control-Allow-Headers: X-Requested-With, Content-Type, Authorization
-```
-
-> [!NOTE]  
-> Most `org.matrix.msc4143.rtc_foci` configurations will only have one entry in
-> the array.
 
 ## Building Element Call
 
@@ -278,7 +257,7 @@ runtime. Documentation and default values for `public/config.json` can be found
 in [ConfigOptions.ts](../src/config/ConfigOptions.ts).
 
 > [!CAUTION]
-> Please note configuring MatrixRTC backend via `config.json` of
+> Please note configuring LiveKit backend via `config.json` of
 > Element Call is only available for developing and debug purposes. Relying on
 > it might break Element Call going forward!
 

locales/en/app.json

@@ -61,7 +61,7 @@
     "crypto_version": "Crypto version: {{version}}",
     "custom_livekit_url": {
       "current_url": "Currently set to: ",
-      "from_config": "Currently, no overwrite is set. Url from well-known or config is used.",
+      "from_config": "Currently, no overwrite is set. Url from config is used.",
       "label": "Custom Livekit-url",
       "reset": "Reset overwrite",
       "save": "Save",

src/config/ConfigOptions.ts

@@ -74,10 +74,7 @@ export interface ConfigOptions {
   livekit?: {
     // The link to the service that returns a livekit url and token to use it.
     // This is a fallback link in case the homeserver in use does not advertise
-    // a livekit service url in the client well-known.
+    // a livekit service url over the transports endpoint.
-    // The well known needs to be formatted like so:
-    // {"type":"livekit", "livekit_service_url":"https://livekit.example.com"}
-    // and stored under the key: "org.matrix.msc4143.rtc_foci"
     livekit_service_url: string;
   };
 

src/settings/__snapshots__/DeveloperSettingsTab.test.tsx.snap

@@ -257,7 +257,7 @@ exports[`DeveloperSettingsTab > renders and matches snapshot 1`] = `
         class="_message_1o4d9_86 _help-message_1o4d9_92"
         id="radix-_r_8_"
       >
-        Currently, no overwrite is set. Url from well-known or config is used.
+        Currently, no overwrite is set. Url from config is used.
       </span>
     </div>
   </form>

src/state/CallViewModel/CallViewModelTestUtils.ts

@@ -138,9 +138,6 @@ export function withCallViewModel(mode: MatrixRTCMode) {
         public getSyncState(): SyncState {
           return syncState;
         }
-        public getAccessToken(): string | null {
-          return "a-token";
-        }
       })() as Partial<MatrixClient> as MatrixClient,
       getMembers: () => roomMembers,
       getMembersWithMembership: () => roomMembers,

src/state/CallViewModel/localMember/LocalMember.test.ts

@@ -20,7 +20,6 @@ import {
   afterAll,
   beforeEach,
 } from "vitest";
-import { AutoDiscovery } from "matrix-js-sdk/lib/autodiscovery";
 import { BehaviorSubject, map, of } from "rxjs";
 import { logger } from "matrix-js-sdk/lib/logger";
 import { type LocalParticipant, type LocalTrack } from "livekit-client";
@@ -78,34 +77,10 @@ describe("LocalMembership", () => {
         livekit_alias: "my-oldest-member-service-alias",
       };
 
-      const focusConfigFromWellKnown = {
-        type: "livekit",
-        livekit_service_url: "http://my-well-known-service-url.com",
-      };
-      const focusConfigFromWellKnown2 = {
-        type: "livekit",
-        livekit_service_url: "http://my-well-known-service-url2.com",
-      };
-      const clientWellKnown = {
-        "org.matrix.msc4143.rtc_foci": [
-          focusConfigFromWellKnown,
-          focusConfigFromWellKnown2,
-        ],
-      };
-
       mockConfig({
         livekit: { livekit_service_url: "http://my-default-service-url.com" },
       });
 
-      vi.spyOn(AutoDiscovery, "getRawClientConfig").mockImplementation(
-        async (domain) => {
-          if (domain === "example.org") {
-            return Promise.resolve(clientWellKnown);
-          }
-          return Promise.resolve({});
-        },
-      );
-
       const mockedSession = vi.mocked({
         room: {
           roomId: "roomId",
@@ -132,7 +107,7 @@ describe("LocalMembership", () => {
         ownMemberMock,
         {
           livekit_alias: "roomId",
-          livekit_service_url: "http://my-well-known-service-url.com",
+          livekit_service_url: "http://my-livekit-service-url.com",
           type: "livekit",
         },
         {
@@ -150,7 +125,7 @@ describe("LocalMembership", () => {
         [
           {
             livekit_alias: "roomId",
-            livekit_service_url: "http://my-well-known-service-url.com",
+            livekit_service_url: "http://my-livekit-service-url.com",
             type: "livekit",
           },
         ],
@@ -161,50 +136,6 @@ describe("LocalMembership", () => {
         }),
       );
     });
-
-    it("It should not fail with configuration error if homeserver config has livekit url but not fallback", () => {
-      mockConfig({});
-      vi.spyOn(AutoDiscovery, "getRawClientConfig").mockResolvedValue({
-        "org.matrix.msc4143.rtc_foci": [
-          {
-            type: "livekit",
-            livekit_service_url: "http://my-well-known-service-url.com",
-          },
-        ],
-      });
-
-      const mockedSession = vi.mocked({
-        room: {
-          roomId: "roomId",
-          client: {
-            getDomain: vi.fn().mockReturnValue("example.org"),
-            getOpenIdToken: vi.fn().mockResolvedValue({
-              access_token: "ACCCESS_TOKEN",
-              token_type: "Bearer",
-              matrix_server_name: "localhost",
-              expires_in: 10000,
-            }),
-          },
-        },
-        memberships: [],
-        getFocusInUse: vi.fn(),
-        joinRTCSession: vi.fn(),
-      }) as unknown as MatrixRTCSession;
-
-      enterRTCSession(
-        mockedSession,
-        ownMemberMock,
-        {
-          livekit_alias: "roomId",
-          livekit_service_url: "http://my-well-known-service-url.com",
-          type: "livekit",
-        },
-        {
-          encryptMedia: true,
-          matrixRTCMode: MATRIX_RTC_MODE,
-        },
-      );
-    });
   });
 
   const defaultCreateLocalMemberValues = {

src/state/CallViewModel/localMember/LocalMember.ts

@@ -117,7 +117,6 @@ export type LocalMemberState =
     };
 
 /*
- * - get well known
  * - get oldest membership
  * - get transport to use
  * - get openId + jwt token

src/state/CallViewModel/localMember/LocalTransport.test.ts

@@ -63,8 +63,7 @@ describe("LocalTransport", () => {
       client: {
         // eslint-disable-next-line @typescript-eslint/naming-convention
         _unstable_getRTCTransports: async () => Promise.resolve([]),
-        getAccessToken: vi.fn().mockReturnValue("access_token"),
+        getDomain: () => "example.org",
-        getDomain: () => "",
         baseUrl: "example.org",
         // These won't be called in this error path but satisfy the type
         getOpenIdToken: vi.fn(),
@@ -77,9 +76,11 @@ describe("LocalTransport", () => {
     await flushPromises();
 
     expect(() => advertised$.value).toThrow(
-      new MatrixRTCTransportMissingError(""),
+      new MatrixRTCTransportMissingError("example.org"),
+    );
+    expect(() => active$.value).toThrow(
+      new MatrixRTCTransportMissingError("example.org"),
     );
-    expect(() => active$.value).toThrow(new MatrixRTCTransportMissingError(""));
   });
 
   it("throws FailToGetOpenIdToken when OpenID fetch fails", async () => {
@@ -103,10 +104,8 @@ describe("LocalTransport", () => {
       useOldestMember: false,
       memberships$: constant(new Epoch<CallMembership[]>([])),
       client: {
-        baseUrl: "https://lk.example.org",
+        baseUrl: "https://example.org",
-        // Use empty domain to skip .well-known and use config directly
+        getDomain: () => "example.org",
-        getDomain: () => "",
-        getAccessToken: vi.fn().mockReturnValue("access_token"),
         // eslint-disable-next-line @typescript-eslint/naming-convention
         _unstable_getRTCTransports: async () => Promise.resolve([]),
         getOpenIdToken: vi.fn(),
@@ -150,11 +149,10 @@ describe("LocalTransport", () => {
       client: {
         // eslint-disable-next-line @typescript-eslint/naming-convention
         _unstable_getRTCTransports: async () => Promise.resolve([]),
-        getDomain: () => "",
+        getDomain: () => "example.org",
         getOpenIdToken: vi.fn(),
         getDeviceId: vi.fn(),
-        baseUrl: "https://lk.example.org",
+        baseUrl: "https://example.org",
-        getAccessToken: vi.fn().mockReturnValue("access_token"),
       },
       ownMembershipIdentity: ownMemberMock,
       forceJwtEndpoint: JwtEndpointVersion.Legacy,
@@ -221,13 +219,12 @@ describe("LocalTransport", () => {
         useOldestMember: true,
         memberships$: scope.behavior(memberships$.pipe(trackEpoch())),
         client: {
-          getDomain: () => "",
+          getDomain: () => "example.org",
           // eslint-disable-next-line @typescript-eslint/naming-convention
           _unstable_getRTCTransports: async () => Promise.resolve([]),
-          getAccessToken: vi.fn().mockReturnValue("access_token"),
           getOpenIdToken: vi.fn(),
           getDeviceId: vi.fn(),
-          baseUrl: "https://lk.example.org",
+          baseUrl: "https://example.org",
         },
         ownMembershipIdentity: ownMemberMock,
         forceJwtEndpoint: JwtEndpointVersion.Legacy,
@@ -278,14 +275,13 @@ describe("LocalTransport", () => {
         useOldestMember: true,
         memberships$: scope.behavior(memberships$.pipe(trackEpoch())),
         client: {
-          getDomain: () => "",
+          getDomain: () => "example.org",
           // eslint-disable-next-line @typescript-eslint/naming-convention
           _unstable_getRTCTransports: async () =>
             Promise.resolve([aliceTransport]),
-          getAccessToken: vi.fn().mockReturnValue("access_token"),
           getOpenIdToken: vi.fn(),
           getDeviceId: vi.fn(),
-          baseUrl: "https://lk.example.org",
+          baseUrl: "https://example.org",
         },
         ownMembershipIdentity: ownMemberMock,
         forceJwtEndpoint: JwtEndpointVersion.Legacy,
@@ -330,10 +326,9 @@ describe("LocalTransport", () => {
         memberships$: constant(new Epoch<CallMembership[]>([])),
         client: {
           baseUrl: "https://example.org",
-          getDomain: vi.fn().mockReturnValue(""),
+          getDomain: vi.fn().mockReturnValue("example.org"),
           // eslint-disable-next-line @typescript-eslint/naming-convention
           _unstable_getRTCTransports: vi.fn().mockResolvedValue([]),
-          getAccessToken: vi.fn().mockReturnValue("access_token"),
           getOpenIdToken: vi.fn(),
           getDeviceId: vi.fn(),
         },
@@ -433,51 +428,6 @@ describe("LocalTransport", () => {
       ).rejects.toThrow(expect.any(FailToGetOpenIdToken));
     });
 
-    it("supports getting transport via well-known", async () => {
-      localTransportOpts.client.getDomain.mockReturnValue("example.org");
-      fetchMock.getOnce("https://example.org/.well-known/matrix/client", {
-        "org.matrix.msc4143.rtc_foci": [
-          { type: "livekit", livekit_service_url: "https://lk.example.org" },
-        ],
-      });
-      const { advertised$, active$ } =
-        createLocalTransport$(localTransportOpts);
-      openIdResolver.resolve?.(openIdResponse);
-      expect(advertised$.value).toBe(null);
-      expect(active$.value).toBe(null);
-      await flushPromises();
-      const expectedTransport = {
-        livekit_service_url: "https://lk.example.org",
-        type: "livekit",
-      };
-      expect(advertised$.value).toStrictEqual(expectedTransport);
-      expect(active$.value).toStrictEqual({
-        transport: expectedTransport,
-        sfuConfig: {
-          jwt: "e30=.eyJzdWIiOiJAbWU6ZXhhbXBsZS5vcmc6QUJDREVGIiwidmlkZW8iOnsicm9vbSI6IiFleGFtcGxlX3Jvb21faWQifX0=.e30=",
-          livekitAlias: "Akph4alDMhen",
-          livekitIdentity: "@lk_user:ABCDEF",
-          url: "https://lk.example.org",
-        },
-      });
-      expect(fetchMock.done()).toEqual(true);
-    });
-
-    it("fails fast if the openId request fails for the well-known config", async () => {
-      localTransportOpts.client.getDomain.mockReturnValue("example.org");
-      fetchMock.getOnce("https://example.org/.well-known/matrix/client", {
-        "org.matrix.msc4143.rtc_foci": [
-          { type: "livekit", livekit_service_url: "https://lk.example.org" },
-        ],
-      });
-      openIdResolver.reject(
-        new FailToGetOpenIdToken(new Error("Test driven error")),
-      );
-      await expect(async () =>
-        lastValueFrom(createLocalTransport$(localTransportOpts).active$),
-      ).rejects.toThrow(expect.any(FailToGetOpenIdToken));
-    });
-
     it("throws if no options are available", async () => {
       const { advertised$, active$ } = createLocalTransport$({
         scope: testScope(),
@@ -488,11 +438,10 @@ describe("LocalTransport", () => {
         delayId$: constant(null),
         memberships$: constant(new Epoch<CallMembership[]>([])),
         client: {
-          getDomain: () => "",
+          getDomain: () => "example.org",
           baseUrl: "https://example.org",
           // eslint-disable-next-line @typescript-eslint/naming-convention
           _unstable_getRTCTransports: async () => Promise.resolve([]),
-          getAccessToken: vi.fn().mockReturnValue("access_token"),
           // These won't be called in this error path but satisfy the type
           getOpenIdToken: vi.fn(),
           getDeviceId: vi.fn(),
@@ -501,10 +450,10 @@ describe("LocalTransport", () => {
       await flushPromises();
 
       expect(() => advertised$.value).toThrow(
-        new MatrixRTCTransportMissingError(""),
+        new MatrixRTCTransportMissingError("example.org"),
       );
       expect(() => active$.value).toThrow(
-        new MatrixRTCTransportMissingError(""),
+        new MatrixRTCTransportMissingError("example.org"),
       );
     });
   });
@@ -529,11 +478,10 @@ describe("LocalTransport", () => {
       delayId$: delayId$,
       memberships$: constant(new Epoch<CallMembership[]>([])),
       client: {
-        getDomain: () => "",
+        getDomain: () => "example.org",
         baseUrl: "https://example.org",
         // eslint-disable-next-line @typescript-eslint/naming-convention
         _unstable_getRTCTransports: async () => Promise.resolve([]),
-        getAccessToken: vi.fn().mockReturnValue("access_token"),
         // These won't be called in this error path but satisfy the type
         getOpenIdToken: vi.fn(),
         getDeviceId: vi.fn(),

src/state/CallViewModel/localMember/LocalTransport.ts

@@ -26,7 +26,6 @@ import {
   tap,
 } from "rxjs";
 import { logger as rootLogger, type Logger } from "matrix-js-sdk/lib/logger";
-import { AutoDiscovery } from "matrix-js-sdk/lib/autodiscovery";
 import { type CallMembershipIdentityParts } from "matrix-js-sdk/lib/matrixrtc/EncryptionManager";
 
 import { type Behavior } from "../../Behavior.ts";
@@ -57,7 +56,7 @@ interface Props {
   memberships$: Behavior<Epoch<CallMembership[]>>;
   client: Pick<
     MatrixClient,
-    "getDomain" | "baseUrl" | "_unstable_getRTCTransports" | "getAccessToken"
+    "getDomain" | "baseUrl" | "_unstable_getRTCTransports"
   > &
     OpenIDClientParts;
   // Used by the jwt service to create the livekit room and compute the livekit alias.
@@ -150,7 +149,6 @@ export const createLocalTransport$ = ({
   const transportDiscovery = new RtcTransportAutoDiscovery({
     client: client,
     resolvedConfig: Config.get(),
-    wellKnownFetcher: AutoDiscovery.getRawClientConfig.bind(AutoDiscovery),
     logger: logger,
   });
 
@@ -309,7 +307,7 @@ async function doOpenIdAndJWTFromUrl(
   roomId: string,
   client: Pick<
     MatrixClient,
-    "getDomain" | "baseUrl" | "_unstable_getRTCTransports" | "getAccessToken"
+    "getDomain" | "baseUrl" | "_unstable_getRTCTransports"
   > &
     OpenIDClientParts,
   delayId?: string,
@@ -339,7 +337,7 @@ function observeLocalTransportForOldestMembership(
   preferredTransport$: Observable<LocalTransportWithSFUConfig>,
   client: Pick<
     MatrixClient,
-    "getDomain" | "baseUrl" | "_unstable_getRTCTransports" | "getAccessToken"
+    "getDomain" | "baseUrl" | "_unstable_getRTCTransports"
   > &
     OpenIDClientParts,
   ownMembershipIdentity: CallMembershipIdentityParts,

src/state/CallViewModel/localMember/RtcTransportAutoDiscovery.test.ts

@@ -13,7 +13,7 @@ import {
   type MockedObject,
   vi,
 } from "vitest";
-import { type IClientWellKnown, MatrixError } from "matrix-js-sdk";
+import { MatrixError } from "matrix-js-sdk";
 import { logger as rootLogger } from "matrix-js-sdk/lib/logger";
 import {
   type LivekitTransportConfig,
@@ -33,9 +33,9 @@ const backendTransport: LivekitTransportConfig = {
   livekit_service_url: "https://backend.example.org",
 };
 
-const wellKnownTransport: LivekitTransportConfig = {
+const configTransport: LivekitTransportConfig = {
   type: "livekit",
-  livekit_service_url: "https://well-known.example.org",
+  livekit_service_url: "https://config.example.org",
 };
 
 function makeClient(): MockedObject<DiscoveryClient> {
@@ -43,7 +43,6 @@ function makeClient(): MockedObject<DiscoveryClient> {
     getDomain: vi.fn().mockReturnValue("example.org"),
     baseUrl: "https://matrix.example.org",
     _unstable_getRTCTransports: vi.fn().mockResolvedValue([]),
-    getAccessToken: vi.fn().mockReturnValue("access_token"),
     getOpenIdToken: vi.fn(),
     getDeviceId: vi.fn(),
   } as unknown as MockedObject<DiscoveryClient>;
@@ -59,12 +58,6 @@ function makeResolvedConfig(livekitServiceUrl?: string): ResolvedConfigOptions {
   } as ResolvedConfigOptions;
 }
 
-function makeWellKnown(rtcFoci?: Transport[]): IClientWellKnown {
-  return {
-    "org.matrix.msc4143.rtc_foci": rtcFoci,
-  } as unknown as IClientWellKnown;
-}
-
 describe("RtcTransportAutoDiscovery", () => {
   beforeEach(() => {
     vi.clearAllMocks();
@@ -75,33 +68,27 @@ describe("RtcTransportAutoDiscovery", () => {
     { transports: [{ type: "not_livekit" }, backendTransport] },
   ];
   it.each(VALID_TEST_CASES)(
-    "prefers backend transport over well-known and app config $transports",
+    "prefers backend transport other app config $transports",
     async ({ transports }) => {
-      // it("prefers backend transport over well-known and app config", async () => {
       const client = makeClient();
       client._unstable_getRTCTransports.mockResolvedValue(transports);
 
-      const wellKnownFetcher = vi
-        .fn<(domain: string) => Promise<IClientWellKnown>>()
-        .mockResolvedValue(makeWellKnown([wellKnownTransport]));
-
       const discovery = new RtcTransportAutoDiscovery({
         client,
-        resolvedConfig: makeResolvedConfig("https://config.example.org"),
+        resolvedConfig: makeResolvedConfig(configTransport.livekit_service_url),
-        wellKnownFetcher,
         logger: rootLogger,
       });
 
-      await expect(
+      const discoveredTransport = await discovery.discoverPreferredTransport();
-        discovery.discoverPreferredTransport(),
+
-      ).resolves.toStrictEqual(backendTransport);
+      expect(discoveredTransport).toStrictEqual(backendTransport);
+      expect(discoveredTransport).not.toStrictEqual(configTransport);
 
       expect(client._unstable_getRTCTransports).toHaveBeenCalledTimes(1);
-      expect(wellKnownFetcher).not.toHaveBeenCalled();
     },
   );
 
-  it("Retries limit_exceeded backend transport over well-known", async () => {
+  it("Retries limit_exceeded backend transport", async () => {
     const client = makeClient();
     client._unstable_getRTCTransports
       .mockRejectedValueOnce(
@@ -116,14 +103,9 @@ describe("RtcTransportAutoDiscovery", () => {
       )
       .mockResolvedValue([backendTransport]);
 
-    const wellKnownFetcher = vi
-      .fn<(domain: string) => Promise<IClientWellKnown>>()
-      .mockResolvedValue(makeWellKnown([wellKnownTransport]));
-
     const discovery = new RtcTransportAutoDiscovery({
       client,
       resolvedConfig: makeResolvedConfig("https://config.example.org"),
-      wellKnownFetcher,
       logger: rootLogger,
     });
 
@@ -132,7 +114,6 @@ describe("RtcTransportAutoDiscovery", () => {
     );
 
     expect(client._unstable_getRTCTransports).toHaveBeenCalledTimes(2);
-    expect(wellKnownFetcher).not.toHaveBeenCalled();
   });
 
   const INVALID_TEST_CASES: Array<{ transports: Transport[] }> = [
@@ -140,67 +121,30 @@ describe("RtcTransportAutoDiscovery", () => {
     { transports: [{ type: "not_livekit" }] },
   ];
   it.each(INVALID_TEST_CASES)(
-    "falls back to well-known when backend has no (valid) livekit transports $transports",
+    "falls back to config when backend has no (valid) livekit transports $transports",
     async ({ transports }) => {
       const client = makeClient();
       client._unstable_getRTCTransports.mockResolvedValue(transports);
 
-      const wellKnownFetcher = vi
-        .fn<(domain: string) => Promise<IClientWellKnown>>()
-        .mockResolvedValue(makeWellKnown([wellKnownTransport]));
-
       const discovery = new RtcTransportAutoDiscovery({
         client,
-        resolvedConfig: makeResolvedConfig("https://config.example.org"),
+        resolvedConfig: makeResolvedConfig(configTransport.livekit_service_url),
-        wellKnownFetcher,
         logger: rootLogger,
       });
 
-      await expect(
+      const discoveredTransport = await discovery.discoverPreferredTransport();
-        discovery.discoverPreferredTransport(),
+      expect(discoveredTransport).not.toStrictEqual(backendTransport);
-      ).resolves.toStrictEqual(wellKnownTransport);
+      expect(discoveredTransport).toStrictEqual(configTransport);
-
-      expect(wellKnownFetcher).toHaveBeenCalledWith("example.org");
     },
   );
 
-  it("falls back to app config when backend fails and well-known has no rtc_foci", async () => {
+  it("returns null when backend and config are all unavailable", async () => {
-    const client = makeClient();
-    client._unstable_getRTCTransports.mockRejectedValue(
-      new MatrixError({ errcode: "M_UNKNOWN" }, 404),
-    );
-
-    const wellKnownFetcher = vi
-      .fn<(domain: string) => Promise<IClientWellKnown>>()
-      .mockResolvedValue({} as IClientWellKnown);
-
-    const discovery = new RtcTransportAutoDiscovery({
-      client,
-      resolvedConfig: makeResolvedConfig("https://config.example.org"),
-      wellKnownFetcher,
-      logger: rootLogger,
-    });
-
-    await expect(discovery.discoverPreferredTransport()).resolves.toStrictEqual(
-      {
-        type: "livekit",
-        livekit_service_url: "https://config.example.org",
-      },
-    );
-  });
-
-  it("returns null when backend, well-known and config are all unavailable", async () => {
     const client = makeClient();
     client._unstable_getRTCTransports.mockResolvedValue([]);
 
-    const wellKnownFetcher = vi
-      .fn<(domain: string) => Promise<IClientWellKnown>>()
-      .mockResolvedValue({} as IClientWellKnown);
-
     const discovery = new RtcTransportAutoDiscovery({
       client,
       resolvedConfig: makeResolvedConfig(undefined),
-      wellKnownFetcher,
       logger: rootLogger,
     });
 

src/state/CallViewModel/localMember/RtcTransportAutoDiscovery.ts

@@ -8,7 +8,7 @@ import {
   isLivekitTransportConfig,
   type LivekitTransportConfig,
 } from "matrix-js-sdk/lib/matrixrtc";
-import { type IClientWellKnown, type MatrixClient } from "matrix-js-sdk";
+import { type MatrixClient } from "matrix-js-sdk";
 import { type Logger } from "matrix-js-sdk/lib/logger";
 
 import type { ResolvedConfigOptions } from "../../../config/ConfigOptions.ts";
@@ -16,33 +16,27 @@ import { doNetworkOperationWithRetry } from "../../../utils/matrix.ts";
 
 type TransportDiscoveryClient = Pick<
   MatrixClient,
-  "getDomain" | "_unstable_getRTCTransports" | "getAccessToken"
+  "getDomain" | "_unstable_getRTCTransports"
 >;
 
 export interface RtcTransportAutoDiscoveryProps {
   client: TransportDiscoveryClient;
   resolvedConfig: ResolvedConfigOptions;
-  wellKnownFetcher: (domain: string) => Promise<IClientWellKnown>;
   logger: Logger;
 }
 
 export class RtcTransportAutoDiscovery {
   private readonly client: TransportDiscoveryClient;
   private readonly resolvedConfig: ResolvedConfigOptions;
-  private readonly wellKnownFetcher: (
-    domain: string,
-  ) => Promise<IClientWellKnown>;
   private readonly logger: Logger;
 
   public constructor({
     client,
     resolvedConfig,
-    wellKnownFetcher,
     logger,
   }: RtcTransportAutoDiscoveryProps) {
     this.client = client;
     this.resolvedConfig = resolvedConfig;
-    this.wellKnownFetcher = wellKnownFetcher;
     this.logger = logger.getChild("[RtcTransportAutoDiscovery]");
   }
 
@@ -56,21 +50,7 @@ export class RtcTransportAutoDiscovery {
       return backendTransport;
     }
 
-    this.logger.info("No backend transport found, falling back to well-known");
+    // 2) app config URL
-    // 2) .well-known transports
-    const wellKnownTransport = await this.tryWellKnownTransports();
-    if (wellKnownTransport) {
-      this.logger.info(
-        `Found .well-known transport: ${wellKnownTransport.livekit_service_url}`,
-      );
-      return wellKnownTransport;
-    }
-
-    this.logger.info(
-      "No .well-known transport found, falling back to app config",
-    );
-
-    // 3) app config URL
     const configTransport = this.tryConfigTransport();
     if (configTransport) {
       this.logger.info(
@@ -110,44 +90,6 @@ export class RtcTransportAutoDiscovery {
     return null;
   }
 
-  /**
-   * Fetches the first rtc_foci from the .well-known/matrix/client.
-   * This will not throw errors, but instead just log them and return null if the expected config is not found or malformed.
-   * @private
-   */
-  private async tryWellKnownTransports(): Promise<LivekitTransportConfig | null> {
-    // Legacy MSC4143 (to be removed) WELL_KNOWN: Prioritize the .well-known/matrix/client, if available.
-    const client = this.client;
-    const domain = client.getDomain();
-    if (domain) {
-      // we use AutoDiscovery instead of relying on the MatrixClient having already
-      // been fully configured and started
-
-      const wellKnownFoci = await this.wellKnownFetcher(domain);
-
-      const fociConfig = wellKnownFoci["org.matrix.msc4143.rtc_foci"];
-      if (fociConfig) {
-        if (!Array.isArray(fociConfig)) {
-          this.logger.warn(
-            `org.matrix.msc4143.rtc_foci is not an array in .well-known`,
-          );
-        } else {
-          return fociConfig[0];
-        }
-      } else {
-        this.logger.info(
-          `No .well-known "org.matrix.msc4143.rtc_foci" found for ${domain}`,
-          wellKnownFoci,
-        );
-      }
-    } else {
-      // Should never happen, but just in case
-      this.logger.warn(`No domain configured for client`);
-    }
-
-    return null;
-  }
-
   private tryConfigTransport(): LivekitTransportConfig | null {
     const url = this.resolvedConfig.livekit?.livekit_service_url;
     if (url) {

src/utils/errors.ts

@@ -12,7 +12,7 @@ import { i18nKey } from "./i18n";
 
 export enum ErrorCode {
   /**
-   * Configuration problem due to no MatrixRTC backend/SFU is exposed via .well-known and no fallback configured.
+   * Configuration problem due to no MatrixRTC transport provided by homeserver and no fallback configured.
    */
   MISSING_MATRIX_RTC_TRANSPORT = "MISSING_MATRIX_RTC_TRANSPORT",
   CONNECTION_LOST_ERROR = "CONNECTION_LOST_ERROR",
@@ -67,7 +67,7 @@ export class ElementCallError extends Error {
 }
 
 /**
- * Configuration problem due to no MatrixRTC backend/SFU is exposed via .well-known and no fallback configured.
+ * Configuration problem due to no MatrixRTC transport provided by homeserver and no fallback configured.
  */
 export class MatrixRTCTransportMissingError extends ElementCallError {
   public domain: string;

src/widget.ts

@@ -198,7 +198,7 @@ export const initializeWidget = (
         // be otherwise)
         await Config.init();
         seedSettingsFromConfig(Config.get().media_quality);
-        await client.startClient({ clientWellKnownPollPeriod: 60 * 10 });
+        await client.startClient();
         return client;
       };