How to rewrite the protected/private route using TypeScript and React-Router 4 and 5?

Question

I was trying to create a <PrivateRoute> as describe in the react-router documents using TypeScript. Can anyone help me out?

The privateRoute in react-router document:

const PrivateRoute = ({ component: Component, ...rest }) => (
  <Route {...rest} render={props => (
    fakeAuth.isAuthenticated ? (
      <Component {...props}/>
    ) : (
      <Redirect to={{pathname: '/login', state: { from: props.location }
   }}/>
  )
 )}/>
)

Below is my TypeScript version(it won't work) :

const PrivateRoute = (theProps: { path: string, component: React.SFC<RouteComponentProps<any> | undefined> | React.ComponentClass<RouteComponentProps<any> | undefined> }) => {
    return <Route path={theProps.path} render={props => (
        fakeAuth.isAuthenticated ? (
            <React.Component {...theProps} /> <!-- **** It will raise error *** -->
        ) : (
                <Redirect to={{
                    pathname: '/',
                    state: { from: props.location }
                }} />
            )
    )} />
}

The <React.Component {...thisProps} /> is not right. The error is: NodeInvocationException: inst.render is not a function TypeError: inst.render is not a function

Answer 1

Probably the error has to do with the typing and the implicit return in rendering. When you fix this you get ultimately to something like this:

const PrivateRoute = ({component, isAuthenticated, ...rest}: any) => {
    const routeComponent = (props: any) => (
        isAuthenticated
            ? React.createElement(component, props)
            : <Redirect to={{pathname: '/login'}}/>
    );
    return <Route {...rest} render={routeComponent}/>;
};

This component can be used like this:

<PrivateRoute
    path='/private'
    isAuthenticated={this.props.state.session.isAuthenticated}
    component={PrivateContainer}
/>

There are a few draw backs with the solution above. One of the is that you lose type safety.

Probably extending the Route component is the better idea.

import * as React from 'react';
import {Redirect, Route, RouteProps} from 'react-router';

export interface ProtectedRouteProps extends RouteProps {
    isAuthenticated: boolean;
    authenticationPath: string;
}

export class ProtectedRoute extends Route<ProtectedRouteProps> {
    public render() {
        let redirectPath: string = '';
        if (!this.props.isAuthenticated) {
            redirectPath = this.props.authenticationPath;
        }

        if (redirectPath) {
            const renderComponent = () => (<Redirect to={{pathname: redirectPath}}/>);
            return <Route {...this.props} component={renderComponent} render={undefined}/>;
        } else {
            return <Route {...this.props}/>;
        }
    }
}

So you can use the component like this:

const defaultProtectedRouteProps: ProtectedRouteProps = {
    isAuthenticated: this.props.state.session.isAuthenticated,
    authenticationPath: '/login',
};

<ProtectedRoute
    {...defaultProtectedRouteProps}
    exact={true}
    path='/'
    component={ProtectedContainer}
/>

Update (Nov 2019)

If you prefer to write functional components you can do it in a very similar manner. This also works with React Router 5:

import * as React from 'react';
import { Redirect, Route, RouteProps } from 'react-router';

export interface ProtectedRouteProps extends RouteProps {
  isAuthenticated: boolean;
  isAllowed: boolean;
  restrictedPath: string;
  authenticationPath: string;
}

export const ProtectedRoute: React.FC<ProtectedRouteProps> = props => {
  let redirectPath = '';
  if (!props.isAuthenticated) {
    redirectPath = props.authenticationPath;
  }
  if (props.isAuthenticated && !props.isAllowed) {
    redirectPath = props.restrictedPath;
  }

  if (redirectPath) {
    const renderComponent = () => <Redirect to={{ pathname: redirectPath }} />;
    return <Route {...props} component={renderComponent} render={undefined} />;
  } else {
    return <Route {...props} />;
  }
};

export default ProtectedRoute;

Update (Dec 2019)

If you want to redirect a user to the path the user wanted to access first, you need to remember the path, so you can redirect after successful authentication. The following answer will guide you through that:

Redirecting a user to the page they requested after successful authentication with react-router-dom