NextJS Authentication

When building web applications, authentication is one of the most critical components to consider. It allows you to manage user sessions and secure access to various features of your app. NextAuth.js is a powerful library designed specifically for Next.js that simplifies the implementation of authentication mechanisms. In this post, we will walk through the steps to set up authentication in a Next.js application using NextAuth.js.

What is NextAuth.js?

NextAuth.js is a complete open-source authentication solution for Next.js applications. It supports multiple authentication providers, including OAuth providers (like Google and GitHub), email/password login, and more. It abstracts much of the complexity involved in session management and provides a simple API for developers.

Step 1: Install NextAuth.js

Create a new Next.js application (if not already created):

npx create-next-app@latest my-next-app
cd my-next-app
Install NextAuth.js:

npm install next-auth

Step 2: Configure NextAuth.js

Create a directory for API routes:

Copy code
mkdir -p pages/api/auth

Step 3: Set Environment Variables

Create a .env.local file at the root of your project. Add your authentication provider credentials (e.g., Google client ID, secret, email server details).

Step 4: Create Sign-In and Sign-Out Functions

Use signIn and signOut functions from NextAuth.js to handle authentication in your components.

Step 5: Use the Session in Your Application

Use the useSession hook from NextAuth.js to access the session data in your components.

Step 6: Protecting Pages

Use getServerSideProps to check the user’s session and redirect unauthenticated users to the sign-in page.

Step 7: Testing the Authentication Flow

Start your Next.js application and test the sign-in, sign-out, and protected pages functionality.