React: Login

npm install @auth0/auth0-react

Under the hood, the Auth0 React SDK uses React Context to manage the authentication state of your users. One way to integrate Auth0 with your React app is to wrap your root component with an Auth0Provider that you can import from the SDK.

import React from "react";
import ReactDOM from "react-dom";
import App from "./App";
import { Auth0Provider } from "@auth0/auth0-react";

ReactDOM.render(
  <Auth0Provider
    domain="{yourDomain}"
    clientId="{yourClientId}"
    authorizationParams={{
      redirect_uri: window.location.origin
    }}
  >
    <App />
  </Auth0Provider>,
  document.getElementById("root")
);

The Auth0Provider component takes the following props:

• domain and clientId: The values of these properties correspond to the "Domain" and "Client ID" values present under the "Settings" of the single-page application that you registered with Auth0.

• authorizationParams.redirect_uri: The URL to where you'd like to redirect your users after they authenticate with Auth0.

Auth0Provider stores the authentication state of your users and the state of the SDK — whether Auth0 is ready to use or not. It also exposes helper methods to log in and log out your users, which you can access using the useAuth0() hook.

The Auth0 React SDK gives you tools to quickly implement user authentication in your React application, such as creating a login button using the loginWithRedirect() method from the useAuth0() hook. Executing loginWithRedirect() redirects your users to the Auth0 Universal Login Page, where Auth0 can authenticate them. Upon successful authentication, Auth0 will redirect your users back to your application.

import React from "react";
import { useAuth0 } from "@auth0/auth0-react";

const LoginButton = () => {
  const { loginWithRedirect } = useAuth0();

  return <button onClick={() => loginWithRedirect()}>Log In</button>;
};

export default LoginButton;

Now that you can log in to your React application, you need a way to log out. You can create a logout button using the logout() method from the useAuth0() hook. Executing logout() redirects your users to your Auth0 logout endpoint (https://YOUR_DOMAIN/v2/logout) and then immediately redirects them to your application.

import React from "react";
import { useAuth0 } from "@auth0/auth0-react";

const LogoutButton = () => {
  const { logout } = useAuth0();

  return (
    <button onClick={() => logout({ logoutParams: { returnTo: window.location.origin } })}>
      Log Out
    </button>
  );
};

export default LogoutButton;

The Auth0 React SDK helps you retrieve the profile information associated with logged-in users quickly in whatever component you need, such as their name or profile picture, to personalize the user interface. The profile information is available through the user property exposed by the useAuth0() hook. Take this Profile component as an example of how to use it:

import React from "react";
import { useAuth0 } from "@auth0/auth0-react";

const Profile = () => {
  const { user, isAuthenticated, isLoading } = useAuth0();

  if (isLoading) {
    return <div>Loading ...</div>;
  }

  return (
    isAuthenticated && (
      <div>
        <img src={user.picture} alt={user.name} />
        <h2>{user.name}</h2>
        <p>{user.email}</p>
      </div>
    )
  );
};

export default Profile;

The user property contains sensitive information and artifacts related to the user's identity. As such, its availability depends on the user's authentication status. To prevent any render errors, use the isAuthenticated property from useAuth0() to check if Auth0 has authenticated the user before React renders any component that consumes the user property. Ensure that the SDK has completed loading before accessing the isAuthenticated property, by checking that isLoading is false.