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Upgrading from react router v5 to v6

Following this tutorial series to try to build a simple React, Electron, and firebase app.
This project mirrors this demo project. I'm getting a lot of compile errors, mostly outdated content and dependencies, but managed to fix most of them up. The main thing I'm struggling with now is upgrading some code from react-router v5 to v6, specifically in app.js
import React, { useState, useEffect } from "react";
import { Router, Routes, Route, Navigate } from "react-router-dom";
import AddMoviePage from "../pages/add-movie-page";
import EditMoviePage from "../pages/edit-movie-page";
import AccountPage from "../pages/account-page";
import MoviesPage from "../pages/movies-page";
import NotFoundPage from "../pages/not-found-page";
import { auth } from "../data/firebase";
import Nav from "./nav";
import { createMemoryHistory } from "history";
function AuthenticatedRoute(props) {
const { isAuthenticated, children, ...routeProps } = props;
return <Route {...routeProps}>{isAuthenticated ? children : <Navigate to="/account" />}</Route>;
}
function App() {
const [user, setUser] = useState(null);
const isAuthenticated = user !== null;
useEffect(() => {
const unsubscribe = auth.onAuthStateChanged((currentUser) => {
setUser(currentUser);
});
return unsubscribe;
}, []);
const history = createMemoryHistory();
console.log(history);
return (
<Router history={history}>
<Nav user={user} />
<Routes>
<Route path="/account">
<AccountPage user={user} />
</Route>
<AuthenticatedRoute path="/" exact isAuthenticated={isAuthenticated}>
<MoviesPage user={user} />
</AuthenticatedRoute>
<AuthenticatedRoute path="/add" isAuthenticated={isAuthenticated}>
<AddMoviePage user={user} />
</AuthenticatedRoute>
<AuthenticatedRoute path="/edit/:id" isAuthenticated={isAuthenticated}>
<EditMoviePage user={user} />
</AuthenticatedRoute>
<Route path="*">
<NotFoundPage />
</Route>
</Routes>
</Router>
);
}
export default App;
I'm getting the following error and can't really figure out what's going on:
Uncaught TypeError: Cannot read properties of undefined (reading 'pathname')
The above error occurred in the <Router> component.

Issues
The main issue here is that you are importing and using the low-level Router component instead of one of the high-level routers (i.e. BrowserRouter, MemoryRouter, HashRouter, etc). The Router component has a couple required props and history isn't one of them.
Router Interface:
declare function Router(
props: RouterProps
): React.ReactElement | null;
interface RouterProps {
basename?: string;
children?: React.ReactNode;
location: Partial<Location> | string; // <-- required!
navigationType?: NavigationType;
navigator: Navigator; // <-- required!
static?: boolean;
}
The high-level routers all instantiate/manage a history reference internally and pass the required props and render the base Router.
Additional issues found in the code:
Another issue is that in react-router-dom#6 custom route components are no longer valid. Only Route components can be rendered by the Routes component. You'll instead convert your older v5 custom route components, a.k.a. AuthenticatedRoute, either into Wrapper components that render the children prop, or as the preferred method a Layout Route.
A final related issue is that Route components and only be rendered by the Routes component or other Route components in the case of building nested routes. In other words, the only valid children components of a Route component is another Route component. The routed content you want to be rendered on a route is passed to the Route component's element prop.
Solution
Convert AuthenticatedRoute to a layout route.
import { Navigate, Outlet } from 'react-router-dom';
function AuthenticatedRoute({ isAuthenticated }) {
if (isAuthenticated === undefined) {
// Don't render the protected content or redirect until we confirm
// authentication status.
return null; // or loading indicator/spinner/etc
}
return isAuthenticated ? <Outlet /> : <Navigate to="/account" replace />;
}
It seems you are wanting to really use a MemoryRouter since you are instantiating your own MemoryHistory object. Import and render the MemoryRouter directly. Move the route "children" onto their respective route's element prop.
Example:
...
import {
MemoryRouter as Router, // <-- import high-level router
Routes,
Route,
Navigate,
Outlet
} from "react-router-dom";
...
function AuthenticatedRoute({ isAuthenticated }) {
if (isAuthenticated === undefined) {
return null; // or loading indicator/spinner/etc
}
return isAuthenticated ? <Outlet /> : <Navigate to="/account" replace />;
}
function App() {
const [user, setUser] = useState(); // <-- initially not auth'd or unauth'd
useEffect(() => {
const unsubscribe = auth.onAuthStateChanged((currentUser) => {
setUser(currentUser); // <-- sets to user object or null
});
return unsubscribe;
}, []);
return (
<Router> // <-- Now really a MemoryRouter
<Nav user={user} />
<Routes>
<Route path="/account" element={<AccountPage user={user} />} />
<Route element={<AuthenticatedRoute isAuthenticated={user} />}>
<Route path="/" element={<MoviesPage user={user} />} />
<Route path="/add" element={<AddMoviePage user={user} />} />
<Route path="/edit/:id" element={<EditMoviePage user={user} />} />
</Route>
<Route path="*" element={<NotFoundPage />} />
</Routes>
</Router>
);
}
export default App;

Redirecting to pages depending on conditionals in ReactJS

Given is an application with 3 pages:
"Mainpage"
"PrivatPage"
"UserManagementPage"
After successful login the user is redirected to a "PrivatPage". On the "PrivatPage" the user has the possibility to return to the "MainPage" or to go to the "UserManagementPage". The part with the redirecting from the "MainPage" to the "PrivatPage" works.
The code looks like this:
import PublicPage from "./components/PublicPage";
import PrivatePage from "./components/PrivatePage";
import UserManagementPage from "./components/UserManagementPage";
import React, { useState, Component } from "react";
import { connect } from "react-redux";
const mapStateToProps = state => {
return state;
};
class App extends Component {
render() {
const accessToken = this.props.accessToken;
console.log(accessToken);
let workspace;
if (accessToken) {
workspace = <PrivatePage />;
} else {
workspace = <PublicPage />;
}
return <div className="App">{workspace}</div>;
}
}
export default connect(mapStateToProps)(App);
But how do I use the conditionals to get to the "UserManagementPage" ?

if you consider functional components, you could use BrowserRouter as follows with react-router-dom.
If you need to handle authentication, you can f.e. build a custom <PrivateRoute /> component and use this on your protected routes instead of <Route />. I always keep these routes in a separate file and import them in App.js.
Here for demo purposes routes in App.js:
import { BrowserRouter as Router } from "react-router-dom";
// import your page components
// and add everything else you want to add to your component
const App = () => {
return (
<>
<Router>
<Routes>
<Route path="/login" element={<Login />} />
<Route path="/private" element={<PrivatePage />} />
<Route path="/public" element={<PublicPage />} />
<Route path="/user" element={<UserManagementPage />} />
</Routes>
</Router>
</>
);
};
export default App;

Adding on to private blocks answer you would then in your components use the
<Redirect to='/your-route' />
You would then create a boolean state variable and once it return true you could redirect immediatley like this (where you are rendering jsx):
render() {
{booleanState && <Redirect to='/your-route' />}
}

How properly setup react-router-dom in Home Route?

I have this index.js:
<Provider store={store}>
<Router history={history}>
<App/>
</Router>
</Provider>
this App.js:
<Switch>
<Route exact path="/" component={Home} />
<Route
path="/login"
render={() => <Login userError={this.state.userError} />}
/>
<Route path="/registration" component={Registration} />;
</Switch>
and Home.js:
<div className="Home">
<Header/>
<div className="content">
<Sidenav/>
<Switch>
<Route path="/friends" component={Friends}/>
</Switch>
<Feed/>
</div>
</div>
I want Friends component to be rendered inside content block, but now if I try to reach /friends route via Link I am getting blank page. If I set /friends Route in App.js, it will be OK, but I won't have it in my content class, because it will be another page.
May you give me a hand with that?
Also in feature I will be have more items to display in content, that's why I put Switch in Home.js
Thanks in advance!

Move your content class and <Friends>
The issue you're having is that the component Home is not rendering when you visit /friends because it will only render when you go to /
To fix this just move the Route into the App.js file, along with the content class into the Friends component.
To make this easier, you could make your content class into a component. This way you could wrap it around all of the stuff you render.
Or move <Friends> and wrap content
What I mean by this is that you could also create your own Route component that wraps whatever component passed to it in a Content component. It might look similar to this:
const ContentRoute = ({ component, ...props }) => (
<Route {...props} component={() => (
<Content>
<component />
</Content>
)}>
</Route>
)

You can access demo here
Here what I have done. This demonstrates how to set layout when page's changing.
- src/
-- components/
--- Header.js
--- Sidenav.js
-- pages/
--- Home.js
--- Login.js
--- withBase.js
-- App.js
-- BaseLayout.js
-- routes.js
At first, let's make dummy components.
components/Header
import React from 'react';
export default () => (
<div>
This is Header.
</div>
);
components/Sidenav
import React from 'react';
export default () => (
<div>
This is Sidenav.
</div>
);
Then, pages.
pages/Home
import React from 'react';
import { NavLink } from 'react-router-dom';
import withBase from './withBase';
const Home = () => (
<div>
<p>Welcome Home!!!</p>
<NavLink to="/login">Go to login page</NavLink>
</div>
);
export default withBase(Home);
pages/Login
import React from 'react';
import { NavLink } from 'react-router-dom';
import withBase from './withBase';
const Login = () => (
<div>
<p>You have to login here...</p>
<NavLink to="/">Go home</NavLink>
</div>
);
export default withBase(Login);
pages/withBase
import React from 'react';
export default WrappedComponent => (
class extends React.Component {
componentDidMount() {
this.props.showHeaderSidenav();
}
render() {
return <WrappedComponent />;
}
}
);
As you see, withBase is a HOC. It runs showHeaderSidenav when the page is mounted.
App
import React from 'react';
import { Switch, Route } from 'react-router-dom';
import BaseLayout from './BaseLayout';
import routes from './routes';
export default class extends React.Component {
state = {
withHeaderSidenav: true
}
showHeaderSidenav = (withHeaderSidenav = true) => {
this.setState({ withHeaderSidenav });
}
render() {
return (
<BaseLayout withHeaderSidenav={this.state.withHeaderSidenav}>
<Switch>
{routes.map(route => (
<Route
exact
key={route.path}
path={route.path}
render={() => (
<route.component
showHeaderSidenav={() => this.showHeaderSidenav(route.withHeaderSidenav)}
/>
)}
/>
))}
</Switch>
</BaseLayout>
);
}
}
BaseLayout
import React from 'react';
import Header from './components/Header';
import Sidenav from './components/Sidenav';
export default ({ withHeaderSidenav, children }) => (
<div>
{withHeaderSidenav && <Header />}
<div className="content">
{withHeaderSidenav && <Sidenav />}
{children}
</div>
</div>
);
We can say that BaseLayout is like a wrapper. It contains dynamic components which will be shown based on withHeaderSidenav prop.
Finally...
routes
import Home from './pages/Home';
import Login from './pages/Login';
export default [
{
path: '/',
component: Home,
withHeaderSidenav: true
},
{
path: '/login',
component: Login,
withHeaderSidenav: false
},
];

You could have moved(declared) content component inside Friends component. I do not see the reason why content component should live outside of Friends component. You can declare content component inside any component that needs it.Content component does not have to mess with routing implementation

React router grab URL segment in component

I'm using a simple router in React
<Router>
<div>
<Switch>
<Route path="/" component={ Home } exact />
<Route path="/contact" component={ Contact } />
<Route path="/:slug" component={ Post } />
</Switch>
</div>
</Router>
I'm pulling posts from a blog using REST and have a router component named Post for single blog posts. Any Route that doesn't match with home or contact, uses the post component.
How can I get or pass the route slug/url segment in the Post component? For example if the url segment/slug is /some-blog-post-title, I want to retrieve it, preferably using a React Router function/method if it exists.

You can get the parameters in the props.match.params object. To get your :slug parameter you would write props.match.params.slug.
Example
class Post extends React.Component {
componentDidMount() {
this.getPost(this.props.match.params.slug);
}
componentDidUpdate(prevProps) {
if (prevProps.match.params.slug !== this.props.match.params.slug) {
this.getPost(this.props.match.params.slug);
}
}
getPost = slug => {
// ...
};
render() {
return <h2>{this.props.match.params.slug}</h2>;
}
}

If you want to grab urls in a functional component
App.js
import React, { Component } from 'react';
import { BrowserRouter as Router, Switch, Route } from 'react-router-dom';
import User from './User';
class App extends Component {
render() {
return (
<Router>
<Switch>
<Route exact path='/user/:userName' component={User} />
<Route>
<div>Default page</div>
</Route>
</Switch>
</Router>
);
}
}
export default App;
Inside the functional component you can grab it
import React from 'react';
import { useParams } from 'react-router-dom';
const User = () => {
const { userName } = useParams();
return (
<div>Username: { userName }</div>
);
}
export default User;

React Router v4 - Nesting Routes Issue

I have the following App component.
class App extends React.Component {
constructor() {
super();
this.state = {}
}
// various methods that interact with state defined here
render() {
const Main = () => (
<div className="main-wrapper">
<ListPicker/>
<ListPane/>
</div>
);
const Search = () => (
<div className="search-wrapper">
<ul className="search-results">
<li>Search Results</li>
</ul>
</div>
);
return (
<div className="app-wrapper">
<Title/>
<SearchBar listResults={this.listResults}/>
<Route exact path="/" component={Main}/>
<Route path="/search" component={Search}/>
</div>
)
}
}
Which is rendered in index.js:
import React from 'react';
import { render } from 'react-dom';
import {
BrowserRouter as Router,
Route
} from 'react-router-dom';
import App from './components/App';
const Root = () => {
return (
<Router>
<div>
<Route exact path="/" component={App}/>
</div>
</Router>
)
};
render(<Root/>, document.getElementById('root'));
Towards the bottom of App you can see I'm trying to have either the Main component or Search component render below <Title/> and <SearchBar/> based on the paths / or /search. As far as I can tell from the React-Router docs, I'm doing what's shown in their example app, but I can't get this to work correctly. With this current setup Main renders fine at / but when navigating to /search nothing renders inside of <Root/>. I also tried wrapping those two <Routes/> in a <Switch/> but got the same result. Am I missing something?

You put a exact Route in you index.js. So the route /search can't find a way. So change to:
const Root = () => {
return (
<Router>
<div>
<Route path="/" component={App}/>
</div>
</Router>
)
};