Create and Implement Your Own Authentication System with NEXT.JS, TypeScript, and NEXTAUTH 🔒

In this tutorial, we will walk through the process of building and deploying your own authentication system using NEXT.JS, TypeScript, and NEXTAUTH. Authentication is a crucial aspect of many web applications, as it ensures that only authorized users can access certain features and functionalities. NEXT.JS is a popular framework for building React applications, and NEXTAUTH is a powerful authentication library that simplifies the process of adding authentication to your projects. By combining these tools with TypeScript, we can create a secure and efficient authentication system for our web applications.

To get started, make sure you have Node.js and npm installed on your machine. You can install them by visiting the Node.js website and following the installation instructions. Once you have Node.js and npm set up, create a new NEXT.JS project by running the following command in your terminal:

npx create-next-app@latest --ts

This command will create a new NEXT.JS project using TypeScript. Navigate into the project directory by running cd your-project-name and install the required dependencies by running npm install.

Next, install NEXTAUTH and its dependencies by running the following command:

npm install next-auth

Now that we have our project set up and all the necessary dependencies installed, we can start building our authentication system. The first step is to create a custom authentication provider using NEXTAUTH. Create a new file in the pages/api/auth directory called [_provider].ts and add the following code:

import { NextApiRequest, NextApiResponse } from "next";
import NextAuth, { InitOptions } from "next-auth";
import Providers from "next-auth/providers";
import { NextAuthOptions } from "next-auth/internals";

const options: NextAuthOptions & InitOptions = {
  pages: {
    signIn: "/auth/signin",
  },
  providers: [
    Providers.GitHub({
      clientId: process.env.GITHUB_ID,
      clientSecret: process.env.GITHUB_SECRET,
    }),
  ],
};

export default (req: NextApiRequest, res: NextApiResponse) =>
  NextAuth(req, res, options);

In this code snippet, we are configuring our NEXTAUTH provider to use GitHub as the authentication provider. You will need to set up a GitHub OAuth App and obtain the client ID and client secret values. You can do this by visiting the GitHub developer settings page.

Next, create a new file in the pages/api/auth directory called signin.ts and add the following code:

import { NextApiRequest, NextApiResponse } from "next";
import { signIn } from "next-auth/react";

export default async (req: NextApiRequest, res: NextApiResponse) => {
  await signIn("github", { callbackUrl: "/" });
};

In this code snippet, we are implementing the sign-in functionality using the signIn method provided by the NEXTAUTH library.

Next, create a new file in the pages/api/auth directory called signout.ts and add the following code:

import { NextApiRequest, NextApiResponse } from "next";
import { signOut } from "next-auth/react";

export default async (req: NextApiRequest, res: NextApiResponse) => {
  await signOut({ redirect: "/" });
};

In this code snippet, we are implementing the sign-out functionality using the signOut method provided by the NEXTAUTH library.

Now that we have set up our authentication provider and the sign-in and sign-out functionality, we can implement the authentication flow in our application. Create a new file in the pages/_app.tsx directory and add the following code:

import { Provider } from "next-auth/react";
import { AppProps } from "next/app";

export default function App({ Component, pageProps }: AppProps) {
  return (
    <Provider session={pageProps.session}>
      <Component {...pageProps} />
    </Provider>
  );
}

In this code snippet, we are wrapping our application component with the Provider component provided by the NEXTAUTH library. This will make the session object accessible throughout our application.

Finally, we can add authentication guards to our pages by creating a new file in the lib/auth.ts directory and adding the following code:

import { useSession } from "next-auth/react";
import { useRouter } from "next/router";
import { useEffect } from "react";

const useRequireAuth = () => {
  const { data: session, status } = useSession();
  const router = useRouter();

  useEffect(() => {
    if (status === "loading") return;
    if (!session) router.replace("/auth/signin");
  }, [session, status]);
};

export { useRequireAuth };

In this code snippet, we are creating a custom hook called useRequireAuth that checks if the user is authenticated. If the user is not authenticated, the hook will redirect them to the sign-in page. We can then use this hook in our pages to protect certain routes and ensure that only authenticated users can access them.

With our authentication system set up, we can now build and deploy our NEXT.JS application. To build the application, run the following command in your terminal:

npm run build

Once the build process is complete, you can deploy your application to a hosting provider of your choice, such as Vercel or Netlify. Make sure to set up environment variables for the client ID and client secret values in your hosting provider’s dashboard.

And that’s it! You have successfully built and deployed your own authentication system using NEXT.JS, TypeScript, and NEXTAUTH. Feel free to customize the authentication provider and add more advanced features to suit your application’s requirements. Happy coding! 🚀🔐