How to Add Authentication to a React App Before Deployment

How to Add Authentication to a React App Before Deployment

Auth must work right before you deploy. Here is how to add and verify authentication in a React app before going live.

Choose an Auth Approach

Use a service like Firebase Auth for simplicity, Auth0 for enterprise features, or a custom backend with JWTs for full control. Firebase is the fastest for a frontend-focused project.

Set Up an Auth Context

Create an AuthContext that tracks the current user and exposes signup, signin, and signout. Wrap your app in the provider so any component can access auth state.

Build Login and Signup Pages

Build forms that call your auth functions. Handle loading and error states, and navigate to the protected area on success.

Protect Routes

Create a ProtectedRoute component that redirects unauthenticated users to the login page. Wrap your protected pages in it so only logged-in users can access them.

Configure Authorized Domains

In your auth provider's dashboard, add your deployed domain to the list of authorized domains. If you skip this, auth redirects will fail in production.

Test the Full Flow

Before deploying, test signup, signin, signout, protected route access, and persistence across reloads. A bug in auth in production is much worse than in development.

Handle Token Refresh and Errors

Make sure your auth handles token refresh and expired sessions gracefully. Users should not be silently logged out without a clear message.

The Takeaway

Add auth by choosing an approach, setting up a context, building login and signup, protecting routes, configuring authorized domains, testing the full flow, and handling token refresh. Test thoroughly before deploy.