Fix well-known lookup for sliding sync labs check (#12519)

* Fix well-known lookup for sliding sync labs check

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Add test

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Iterate

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

---------

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/SlidingSyncManager.ts

@@ -359,10 +359,10 @@ export class SlidingSyncManager {
         let proxyUrl: string | undefined;
 
         try {
-            const clientWellKnown = await AutoDiscovery.findClientConfig(client.baseUrl);
+            const clientWellKnown = await AutoDiscovery.findClientConfig(client.getDomain()!);
             proxyUrl = clientWellKnown?.["org.matrix.msc3575.proxy"]?.url;
         } catch (e) {
-            // client.baseUrl is invalid, `AutoDiscovery.findClientConfig` has thrown
+            // client.getDomain() is invalid, `AutoDiscovery.findClientConfig` has thrown
         }
 
         if (proxyUrl != undefined) {
@@ -401,7 +401,7 @@ export class SlidingSyncManager {
 
         const proxyUrl = await this.getProxyFromWellKnown(client);
         if (proxyUrl != undefined) {
-            const response = await fetch(proxyUrl + "/client/server.json", {
+            const response = await fetch(new URL("/client/server.json", proxyUrl), {
                 method: Method.Get,
                 signal: timeoutSignal(10 * 1000), // 10s
             });

test/SlidingSyncManager-test.ts

@@ -17,6 +17,7 @@ limitations under the License.
 import { SlidingSync } from "matrix-js-sdk/src/sliding-sync";
 import { mocked } from "jest-mock";
 import { MatrixClient, MatrixEvent, Room } from "matrix-js-sdk/src/matrix";
+import fetchMockJest from "fetch-mock-jest";
 
 import { SlidingSyncManager } from "../src/SlidingSyncManager";
 import { stubClient } from "./test-utils";
@@ -39,6 +40,8 @@ describe("SlidingSyncManager", () => {
         mocked(client.getRoom).mockReturnValue(null);
         manager.configure(client, "invalid");
         manager.slidingSync = slidingSync;
+        fetchMockJest.reset();
+        fetchMockJest.get("https://proxy/client/server.json", {});
     });
 
     describe("setRoomVisible", () => {
@@ -236,7 +239,7 @@ describe("SlidingSyncManager", () => {
     describe("checkSupport", () => {
         beforeEach(() => {
             SlidingSyncController.serverSupportsSlidingSync = false;
-            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("proxy");
+            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("https://proxy/");
         });
         it("shorts out if the server has 'native' sliding sync support", async () => {
             jest.spyOn(manager, "nativeSlidingSyncSupport").mockResolvedValue(true);
@@ -252,6 +255,25 @@ describe("SlidingSyncManager", () => {
             expect(manager.getProxyFromWellKnown).toHaveBeenCalled();
             expect(SlidingSyncController.serverSupportsSlidingSync).toBeTruthy();
         });
+        it("should query well-known on server_name not baseUrl", async () => {
+            fetchMockJest.get("https://matrix.org/.well-known/matrix/client", {
+                "m.homeserver": {
+                    base_url: "https://matrix-client.matrix.org",
+                    server: "matrix.org",
+                },
+                "org.matrix.msc3575.proxy": {
+                    url: "https://proxy/",
+                },
+            });
+            fetchMockJest.get("https://matrix-client.matrix.org/_matrix/client/versions", { versions: ["v1.4"] });
+
+            mocked(manager.getProxyFromWellKnown).mockRestore();
+            jest.spyOn(manager, "nativeSlidingSyncSupport").mockResolvedValue(false);
+            expect(SlidingSyncController.serverSupportsSlidingSync).toBeFalsy();
+            await manager.checkSupport(client);
+            expect(SlidingSyncController.serverSupportsSlidingSync).toBeTruthy();
+            expect(fetchMockJest).not.toHaveFetched("https://matrix-client.matrix.org/.well-known/matrix/client");
+        });
     });
     describe("nativeSlidingSyncSupport", () => {
         beforeEach(() => {
@@ -266,7 +288,7 @@ describe("SlidingSyncManager", () => {
                     expect(feature).toBe("org.matrix.msc3575");
                     return true;
                 });
-            const proxySpy = jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("proxy");
+            const proxySpy = jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("https://proxy/");
 
             expect(SlidingSyncController.serverSupportsSlidingSync).toBeFalsy();
             await manager.checkSupport(client); // first thing it does is call nativeSlidingSyncSupport
@@ -287,14 +309,14 @@ describe("SlidingSyncManager", () => {
             expect(manager.startSpidering).toHaveBeenCalled();
         });
         it("uses the proxy declared in the client well-known", async () => {
-            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("proxy");
+            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("https://proxy/");
             await manager.setup(client);
             expect(manager.configure).toHaveBeenCalled();
-            expect(manager.configure).toHaveBeenCalledWith(client, "proxy");
+            expect(manager.configure).toHaveBeenCalledWith(client, "https://proxy/");
             expect(manager.startSpidering).toHaveBeenCalled();
         });
         it("uses the legacy `feature_sliding_sync_proxy_url` if it was set", async () => {
-            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("proxy");
+            jest.spyOn(manager, "getProxyFromWellKnown").mockResolvedValue("https://proxy/");
             jest.spyOn(SettingsStore, "getValue").mockImplementation((name: string) => {
                 if (name === "feature_sliding_sync_proxy_url") return "legacy-proxy";
             });