Allow hiding the room directory at all

- helpful together with allow list

config/config.default.json

@@ -26,4 +26,6 @@
   //"enableAllowList": true,
   // use room ids starting with a `!`, not aliases
   //"roomAllowList": ["!ypQyNeReyEPUCKYjPU:matrix.org"],  // e.g. room about Matrix Reputation
+  // Hide room directory (will enable auto redirect to first entry of allow list)
+  //"hideRoomDirectory": true,
 }

server/routes/room-directory-routes.js

@@ -14,6 +14,7 @@ const checkIfAllowed = require('../lib/matrix-utils/check-room-allowed');
 const fetchAccessibleRooms = require('../lib/matrix-utils/fetch-accessible-rooms');
 const renderHydrogenVmRenderScriptToPageHtml = require('../hydrogen-render/render-hydrogen-vm-render-script-to-page-html');
 const setHeadersToPreloadAssets = require('../lib/set-headers-to-preload-assets');
+const MatrixViewerURLCreator = require('matrix-viewer-shared/lib/url-creator');
 
 const config = require('../lib/config');
 const basePath = config.get('basePath');
@@ -25,6 +26,8 @@ assert(matrixServerName);
 const matrixAccessToken = config.get('matrixAccessToken');
 assert(matrixAccessToken);
 
+const matrixViewerURLCreator = new MatrixViewerURLCreator(basePath);
+
 const router = express.Router({
   caseSensitive: true,
   // Preserve the req.params values from the parent router.
@@ -35,6 +38,11 @@ router.get(
   '/',
   identifyRoute('app-room-directory-index'),
   asyncHandler(async function (req, res) {
+    if (config.get("hideRoomDirectory")) {
+      res.redirect(matrixViewerURLCreator.roomUrl(config.get("roomAllowList")[0]));
+      return;
+    }
+
     const searchTerm = req.query.search;
     const homeserver = req.query.homeserver;
     const paginationToken = req.query.page;
@@ -84,6 +92,7 @@ router.get(
 
     // limit to allow list
     // Because filtering happens after checking the directory this may lead into a bad UX.
+    // Consider setting hideDirectory
     if (config.get("enableAllowList")) {
       const checkResults = await Promise.all(rooms.map((r) => r.room_id).map(checkIfAllowed));
       rooms = rooms.filter((_v, index) => checkResults[index]);