store fragmentafterlogin in sesison storage for oidc login (#25688)

src/vector/app.tsx

@@ -38,7 +38,7 @@ import { QueryDict, encodeParams } from "matrix-js-sdk/src/utils";
 
 import { parseQs } from "./url_utils";
 import VectorBasePlatform from "./platform/VectorBasePlatform";
-import { getScreenFromLocation, init as initRouting, onNewScreen } from "./routing";
+import { getInitialScreenAfterLogin, getScreenFromLocation, init as initRouting, onNewScreen } from "./routing";
 
 // add React and ReactPerf to the global namespace, to make them easier to access via the console
 // this incidentally means we can forget our React imports in JSX files without penalty.
@@ -133,6 +133,8 @@ export async function loadApp(fragParams: {}): Promise<ReactElement> {
     const defaultDeviceName =
         snakedConfig.get("default_device_display_name") ?? platform?.getDefaultDeviceDisplayName();
 
+    const initialScreenAfterLogin = getInitialScreenAfterLogin(window.location);
+
     return (
         <MatrixChat
             onNewScreen={onNewScreen}
@@ -142,7 +144,7 @@ export async function loadApp(fragParams: {}): Promise<ReactElement> {
             startingFragmentQueryParams={fragParams}
             enableGuest={!config.disable_guests}
             onTokenLoginCompleted={onTokenLoginCompleted}
-            initialScreenAfterLogin={getScreenFromLocation(window.location)}
+            initialScreenAfterLogin={initialScreenAfterLogin}
             defaultDeviceDisplayName={defaultDeviceName}
         />
     );

src/vector/routing.ts

@@ -76,3 +76,36 @@ export function onNewScreen(screen: string, replaceLast = false): void {
 export function init(): void {
     window.addEventListener("hashchange", onHashChange);
 }
+
+const ScreenAfterLoginStorageKey = "mx_screen_after_login";
+function getStoredInitialScreenAfterLogin(): ReturnType<typeof getScreenFromLocation> | undefined {
+    const screenAfterLogin = sessionStorage.getItem(ScreenAfterLoginStorageKey);
+
+    return screenAfterLogin ? JSON.parse(screenAfterLogin) : undefined;
+}
+
+function setInitialScreenAfterLogin(screenAfterLogin?: ReturnType<typeof getScreenFromLocation>): void {
+    if (screenAfterLogin?.screen) {
+        sessionStorage.setItem(ScreenAfterLoginStorageKey, JSON.stringify(screenAfterLogin));
+    }
+}
+
+/**
+ * Get the initial screen to be displayed after login,
+ * for example when trying to view a room via a link before logging in
+ *
+ * If the current URL has a screen set that in session storage
+ * Then retrieve the screen from session storage and return it
+ * Using session storage allows us to remember login fragments from when returning from OIDC login
+ * @returns screen and params or undefined
+ */
+export function getInitialScreenAfterLogin(location: Location): ReturnType<typeof getScreenFromLocation> | undefined {
+    const screenAfterLogin = getScreenFromLocation(location);
+
+    if (screenAfterLogin.screen || screenAfterLogin.params) {
+        setInitialScreenAfterLogin(screenAfterLogin);
+    }
+
+    const storedScreenAfterLogin = getStoredInitialScreenAfterLogin();
+    return storedScreenAfterLogin;
+}