Look up tile server info in homeserver's .well-known area

src/components/views/location/LocationPicker.tsx

@@ -19,14 +19,14 @@ import maplibregl from 'maplibre-gl';
 import { logger } from "matrix-js-sdk/src/logger";
 import { RoomMember } from 'matrix-js-sdk/src/models/room-member';
 
-import SdkConfig from '../../../SdkConfig';
 import DialogButtons from "../elements/DialogButtons";
 import { _t } from '../../../languageHandler';
 import { replaceableComponent } from "../../../utils/replaceableComponent";
 import MemberAvatar from '../avatars/MemberAvatar';
 import MatrixClientContext from '../../../contexts/MatrixClientContext';
 import Modal from '../../../Modal';
 import ErrorDialog from '../dialogs/ErrorDialog';
+import { findMapStyleUrl } from '../messages/MLocationBody';
 
 interface IProps {
     sender: RoomMember;
@@ -69,10 +69,9 @@ class LocationPicker extends React.Component<IProps, IState> {
     };
 
     componentDidMount() {
-        const config = SdkConfig.get();
         this.map = new maplibregl.Map({
             container: 'mx_LocationPicker_map',
-            style: config.map_style_url,
+            style: findMapStyleUrl(),
             center: [0, 0],
             zoom: 1,
         });

src/components/views/messages/MLocationBody.tsx

@@ -35,6 +35,7 @@ import LocationViewDialog from '../location/LocationViewDialog';
 import TooltipTarget from '../elements/TooltipTarget';
 import { Alignment } from '../elements/Tooltip';
 import AccessibleButton from '../elements/AccessibleButton';
+import { getTileServerWellKnown } from '../../../utils/WellKnownUtils';
 
 interface IState {
     error: Error;
@@ -206,14 +207,27 @@ function ZoomButtons(props: IZoomButtonsProps): React.ReactElement<HTMLDivElemen
     </div>;
 }
 
+/**
+ * Look up what map tile server style URL was provided in the homeserver's
+ * .well-known location, or, failing that, in our local config, or, failing
+ * that, defaults to the same tile server listed by matrix.org.
+ */
+export function findMapStyleUrl(): string {
+    return (
+        getTileServerWellKnown().map_style_url ??
+        SdkConfig.get().map_style_url ??
+        "https://api.maptiler.com/maps/streets/style.json?key=fU3vlMsMn4Jb6dnEIFsx"
+    );
+}
+
 export function createMap(
     coords: GeolocationCoordinates,
     interactive: boolean,
     bodyId: string,
     markerId: string,
     onError: (error: Error) => void,
 ): maplibregl.Map {
-    const styleUrl = SdkConfig.get().map_style_url;
+    const styleUrl = findMapStyleUrl();
     const coordinates = new maplibregl.LngLat(coords.longitude, coords.latitude);
 
     const map = new maplibregl.Map({

src/utils/WellKnownUtils.ts

@@ -14,11 +14,15 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+import { UnstableValue } from 'matrix-js-sdk/src/NamespacedValue';
+
 import { MatrixClientPeg } from '../MatrixClientPeg';
 
 const CALL_BEHAVIOUR_WK_KEY = "io.element.call_behaviour";
 const E2EE_WK_KEY = "io.element.e2ee";
 const E2EE_WK_KEY_DEPRECATED = "im.vector.riot.e2ee";
+const TILE_SERVER_WK_KEY = new UnstableValue(
+    "m.tile_server", "org.matrix.msc3488.tile_server");
 
 /* eslint-disable camelcase */
 export interface ICallBehaviourWellKnown {
@@ -30,6 +34,10 @@ export interface IE2EEWellKnown {
     secure_backup_required?: boolean;
     secure_backup_setup_methods?: SecureBackupSetupMethod[];
 }
+
+export interface ITileServerWellKnown {
+    map_style_url?: string;
+}
 /* eslint-enable camelcase */
 
 export function getCallBehaviourWellKnown(): ICallBehaviourWellKnown {
@@ -48,6 +56,14 @@ export function getE2EEWellKnown(): IE2EEWellKnown {
     return null;
 }
 
+export function getTileServerWellKnown(): ITileServerWellKnown {
+    const clientWellKnown = MatrixClientPeg.get().getClientWellKnown();
+    return (
+        clientWellKnown?.[TILE_SERVER_WK_KEY.name] ??
+        clientWellKnown?.[TILE_SERVER_WK_KEY.altName]
+    );
+}
+
 export function isSecureBackupRequired(): boolean {
     const wellKnown = getE2EEWellKnown();
     return wellKnown && wellKnown["secure_backup_required"] === true;