♻️(frontend) Refactor Auth component for improved redirection logic

Move redirects from render
to a guarded useEffect
to avoid triggering multiple redirects
on every re-render.

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to
 
 ### Changed
 
+- ♻️(frontend) Refactor Auth component for improved redirection logic #1461
 - ♻️(frontend) replace Arial font-family with token font #1411
 - ♿(frontend) improve accessibility:
   - ♿(frontend) enable enter key to open documentss #1354

src/frontend/apps/impress/src/features/auth/components/Auth.tsx

@@ -1,8 +1,7 @@
-import { Loader } from '@openfun/cunningham-react';
 import { useRouter } from 'next/router';
-import { PropsWithChildren } from 'react';
+import { PropsWithChildren, useEffect, useState } from 'react';
 
-import { Box } from '@/components';
+import { Loading } from '@/components';
 import { useConfig } from '@/core';
 
 import { HOME_URL } from '../conf';
@@ -14,57 +13,65 @@ export const Auth = ({ children }: PropsWithChildren) => {
     useAuth();
   const { replace, pathname } = useRouter();
   const { data: config } = useConfig();
-
-  if (isLoading && !isFetchedAfterMount) {
-    return (
-      <Box $height="100vh" $width="100vw" $align="center" $justify="center">
-        <Loader />
-      </Box>
-    );
-  }
+  const [isRedirecting, setIsRedirecting] = useState(false);
 
   /**
-   * If the user is authenticated and wanted initially to access a document,
-   * we redirect to the document page.
+   * If the user is authenticated and initially wanted to access a specific page, redirect him to that page now.
    */
-  if (authenticated) {
+  useEffect(() => {
+    if (!authenticated || isRedirecting) {
+      return;
+    }
+
     const authUrl = getAuthUrl();
     if (authUrl) {
-      void replace(authUrl);
-      return (
-        <Box $height="100vh" $width="100vw" $align="center" $justify="center">
-          <Loader />
-        </Box>
-      );
+      setIsRedirecting(true);
+      void replace(authUrl).then(() => setIsRedirecting(false));
     }
+  }, [authenticated, isRedirecting, pathname, replace]);
+
+  /**
+   * If the user is not authenticated and not on a allowed pages
+   */
+  useEffect(() => {
+    if (isLoading || authenticated || pathAllowed || isRedirecting) {
+      return;
     }
 
     /**
-   * If the user is not authenticated and the path is not allowed, we redirect to the login page.
+     * The homepage feature is enabled, redirect them to the homepage
      */
-  if (!authenticated && !pathAllowed) {
     if (config?.FRONTEND_HOMEPAGE_FEATURE_ENABLED) {
-      void replace(HOME_URL);
-    } else {
-      gotoLogin();
+      if (pathname !== HOME_URL) {
+        setIsRedirecting(true);
+        void replace(HOME_URL).then(() => setIsRedirecting(false));
       }
-    return (
-      <Box $height="100vh" $width="100vw" $align="center" $justify="center">
-        <Loader />
-      </Box>
-    );
+
+      return;
     }
 
     /**
-   * If the user is authenticated and the path is the home page, we redirect to the index.
+     * Redirect them to login page
      */
-  if (pathname === HOME_URL && authenticated) {
-    void replace('/');
-    return (
-      <Box $height="100vh" $width="100vw" $align="center" $justify="center">
-        <Loader />
-      </Box>
-    );
+    setIsRedirecting(true);
+    gotoLogin();
+  }, [
+    authenticated,
+    pathAllowed,
+    config?.FRONTEND_HOMEPAGE_FEATURE_ENABLED,
+    replace,
+    isLoading,
+    isRedirecting,
+    pathname,
+  ]);
+
+  const shouldShowLoader =
+    (isLoading && !isFetchedAfterMount) ||
+    isRedirecting ||
+    (!authenticated && !pathAllowed);
+
+  if (shouldShowLoader) {
+    return <Loading $height="100vh" $width="100vw" />;
   }
 
   return children;

src/frontend/apps/impress/src/features/auth/conf.ts

@@ -1,6 +1,6 @@
 import { baseApiUrl } from '@/api';
 
-export const HOME_URL = '/home';
+export const HOME_URL: string = '/home';
 export const LOGIN_URL = `${baseApiUrl()}authenticate/`;
 export const LOGOUT_URL = `${baseApiUrl()}logout/`;
 export const PATH_AUTH_LOCAL_STORAGE = 'docs-path-auth';

src/frontend/apps/impress/src/features/auth/utils.ts

@@ -1,7 +1,15 @@
 import { terminateCrispSession } from '@/services/Crisp';
 
-import { LOGIN_URL, LOGOUT_URL, PATH_AUTH_LOCAL_STORAGE } from './conf';
+import {
+  HOME_URL,
+  LOGIN_URL,
+  LOGOUT_URL,
+  PATH_AUTH_LOCAL_STORAGE,
+} from './conf';
 
+/**
+ * Get the stored auth URL from local storage
+ */
 export const getAuthUrl = () => {
   const path_auth = localStorage.getItem(PATH_AUTH_LOCAL_STORAGE);
   if (path_auth) {
@@ -10,8 +18,15 @@ export const getAuthUrl = () => {
   }
 };
 
+/**
+ * Store the current path in local storage if it's not the homepage or root
+ * so we can redirect the user to this path after login
+ */
 export const setAuthUrl = () => {
-  if (window.location.pathname !== '/') {
+  if (
+    window.location.pathname !== '/' &&
+    window.location.pathname !== `${HOME_URL}/`
+  ) {
     localStorage.setItem(PATH_AUTH_LOCAL_STORAGE, window.location.pathname);
   }
 };

src/frontend/apps/impress/src/pages/home/index.tsx

@@ -1,7 +1,30 @@
+import { useRouter } from 'next/router';
+import { useEffect } from 'react';
+
+import { Loading } from '@/components';
+import { useAuth } from '@/features/auth';
 import { HomeContent } from '@/features/home';
 import { NextPageWithLayout } from '@/types/next';
 
 const Page: NextPageWithLayout = () => {
+  const { authenticated } = useAuth();
+  const { replace } = useRouter();
+
+  /**
+   * If the user is authenticated we redirect him to the index page (grid).
+   */
+  useEffect(() => {
+    if (!authenticated) {
+      return;
+    }
+
+    void replace('/');
+  }, [authenticated, replace]);
+
+  if (authenticated) {
+    return <Loading $height="100vh" $width="100vw" />;
+  }
+
   return <HomeContent />;
 };