This comprehensive guide walks you through implementing OAuth 2.0 authentication in React applications, covering everything from initial setup to production deployment.

Prerequisites

• React 18+
• Node.js 16+
• Basic understanding of authentication concepts

Step 1: Project Setup

First, install the necessary dependencies:

npm install @authcompany/react-sdk react-router-dom

Step 2: Configure Authentication Provider

Create an authentication context:

import { createContext, useContext } from 'react';
import { AuthProvider } from '@authcompany/react-sdk';

const AuthContext = createContext();

export function AuthWrapper({ children }) {
  return (
    <AuthProvider
      clientId={process.env.REACT_APP_CLIENT_ID}
      domain={process.env.REACT_APP_AUTH_DOMAIN}
      redirectUri={window.location.origin + '/callback'}
    >
      {children}
    </AuthProvider>
  );
}

Step 3: Implement Protected Routes

Create a protected route component:

import { useAuth } from '@authcompany/react-sdk';
import { Navigate } from 'react-router-dom';

function ProtectedRoute({ children }) {
  const { isAuthenticated, isLoading } = useAuth();
  
  if (isLoading) return <div>Loading...</div>;
  if (!isAuthenticated) return <Navigate to="/login" />;
  
  return children;
}

Step 4: Add Login/Logout Functionality

Implement authentication controls:

function LoginButton() {
  const { loginWithRedirect } = useAuth();
  
  return (
    <button onClick={() => loginWithRedirect()}>
      Log In
    </button>
  );
}

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

Step 5: Handle Callback Route

Create a callback component to handle the OAuth redirect:

import { useEffect } from 'react';
import { useAuth } from '@authcompany/react-sdk';
import { useNavigate } from 'react-router-dom';

function CallbackPage() {
  const { handleRedirectCallback } = useAuth();
  const navigate = useNavigate();
  
  useEffect(() => {
    const handleCallback = async () => {
      await handleRedirectCallback();
      navigate('/dashboard');
    };
    
    handleCallback();
  }, []);
  
  return <div>Processing authentication...</div>;
}

Security Best Practices

1. Always use PKCE for public clients
2. Store tokens securely (avoid localStorage)
3. Implement proper CORS policies
4. Use HTTPS in production
5. Validate tokens on the backend

Troubleshooting Common Issues

• Redirect URI mismatch errors
• CORS configuration problems
• Token expiration handling
• State management conflicts

With this implementation, you'll have a secure OAuth 2.0 authentication flow in your React application that follows industry best practices.