Simplest Next.js Authentication for your SaaS

Next.js is a popular framework for building React applications and it makes it easy to create a robust authentication system for your SaaS product. In this article, we will discuss the simplest way to implement authentication in a Next.js application.

Step 1: Install necessary packages

First, you need to install some packages that will help you with authentication in your Next.js app. You can do this by running the following command:

npm install next-auth

Step 2: Configure NextAuth

NextAuth is a library that makes it easy to add authentication to your Next.js app. You can configure it by creating a new file in your project called `pages/api/auth/[…nextauth].js` and adding the following code:

import NextAuth from "next-auth"
import Providers from "next-auth/providers"

export default NextAuth({
  providers: [
    Providers.GitHub({
      clientId: process.env.GITHUB_ID,
      clientSecret: process.env.GITHUB_SECRET,
    }),
  ],
})

In this example, we are using GitHub as the authentication provider. You can easily switch to other providers such as Google, Facebook, or Twitter by changing the `Providers.GitHub` to `Providers.Google`, `Providers.Facebook`, or `Providers.Twitter` respectively.

Step 3: Add authentication to your pages

Now that you have configured NextAuth, you can add authentication to your pages by using the `getSession` and `signIn` functions provided by NextAuth. Here is an example of how you can do this:

import { signIn, getSession } from "next-auth/react"

export default function Home() {
  const session = getSession()

  return (
    
      {session ? (
         signOut()}>Sign out
      ) : (
         signIn()}>Sign in with GitHub
      )}
    
  )
}

Step 4: Protect your routes

Finally, you can protect your routes by adding a custom `useSession` hook to check if the user is authenticated. Here is an example of how you can do this:

import { useSession } from "next-auth/react"

export default function ProtectedPage() {
  const session = useSession()

  if (!session) {
    return 
You need to be authenticated to access this page.
  }

  return 
Welcome, {session.user.name}!
}

And that’s it! You now have a simple authentication system in your Next.js app for your SaaS product. Feel free to customize it further to fit your needs.