next-auth

What is next-auth?

NextAuth.js is a complete open-source authentication solution for Next.js applications. It provides a simple and secure way to add authentication to your Next.js app, supporting various authentication providers, including OAuth, email/password, and custom credentials.

What are next-auth's main functionalities?

OAuth Authentication

NextAuth.js supports OAuth authentication with various providers like Google, Facebook, GitHub, etc. The code sample demonstrates how to configure Google and Facebook OAuth providers.

```javascript
import NextAuth from 'next-auth';
import Providers from 'next-auth/providers';

export default NextAuth({
  providers: [
    Providers.Google({
      clientId: process.env.GOOGLE_CLIENT_ID,
      clientSecret: process.env.GOOGLE_CLIENT_SECRET
    }),
    Providers.Facebook({
      clientId: process.env.FACEBOOK_CLIENT_ID,
      clientSecret: process.env.FACEBOOK_CLIENT_SECRET
    })
  ]
});
```

Email/Password Authentication

NextAuth.js allows email/password authentication by sending magic links to users' email addresses. The code sample shows how to configure the email provider.

```javascript
import NextAuth from 'next-auth';
import Providers from 'next-auth/providers';

export default NextAuth({
  providers: [
    Providers.Email({
      server: process.env.EMAIL_SERVER,
      from: process.env.EMAIL_FROM
    })
  ]
});
```

Custom Credentials Authentication

NextAuth.js supports custom credentials authentication, allowing you to define your own logic for authenticating users. The code sample demonstrates a simple username/password authentication.

```javascript
import NextAuth from 'next-auth';
import Providers from 'next-auth/providers';

export default NextAuth({
  providers: [
    Providers.Credentials({
      name: 'Credentials',
      credentials: {
        username: { label: 'Username', type: 'text' },
        password: { label: 'Password', type: 'password' }
      },
      authorize: async (credentials) => {
        const user = { id: 1, name: 'User' };
        if (credentials.username === 'user' && credentials.password === 'password') {
          return Promise.resolve(user);
        } else {
          return Promise.resolve(null);
        }
      }
    })
  ]
});
```

Session Management

NextAuth.js provides session management, allowing you to access the user's session data on both the client and server sides. The code sample shows how to retrieve the session in a Next.js page using getServerSideProps.

```javascript
import { getSession } from 'next-auth/client';

export async function getServerSideProps(context) {
  const session = await getSession(context);
  return {
    props: { session }
  };
}
```

Other packages similar to next-auth

passport

Passport is a popular authentication middleware for Node.js. It is highly flexible and supports a wide range of authentication strategies. Compared to NextAuth.js, Passport requires more manual setup and configuration, but it offers greater flexibility and can be used with any Node.js framework.

auth0

Auth0 is a cloud-based authentication service that provides a comprehensive solution for authentication and authorization. It supports various authentication methods and integrates well with many platforms. Compared to NextAuth.js, Auth0 is a third-party service that requires a subscription for advanced features, but it offers a more extensive set of features and easier integration with multiple platforms.

firebase-auth

Firebase Authentication is a part of Google's Firebase platform, providing backend services to authenticate users in your app. It supports email/password, phone number, and various social providers. Compared to NextAuth.js, Firebase Authentication is a managed service that integrates seamlessly with other Firebase services, but it may not offer the same level of customization as NextAuth.js.

README

NextAuth

About NextAuth

This is work in progress of version 2.0 of NextAuth, an authentication library for Next.js.

Version 2.0 is a complete re-write, designed from the ground up for serverless.

NextAuth is a complete self-hosted application solution for Next.js applications.

It allows you to easily add sign in support to an application, without any third party service dependancies.

You provide database connnection details (MySQL, Postgres, MongoDB, etc) and NextAuth does the rest!

Features

• Built for Next.js and for Serverless (but works in any environment)
• Lightweight - doesn't depend on Express or PassportJS
• Supports oAuth 1.x, oAuth 2.x and email / passwordless authentication
• Out of the box support for signing in with Google, Facebook, Twitter, GitHub, Slack, Discord, Twitch and other providers
• Exteremly simple to use client, with useSession() hook and isomorphic session() method
• Supports both SQL and document storage databases with the default database adapter (TypeORM)
• Secure / host only and http only signed cookies; session ID never exposed to client side JavaScript
• Cross Site Request Forgery proteciton (using double submit cookie method with a signed, HTTP only, host only prefixed cookie)
• Works without JavaScript in the client (e.g. great for integration with Google AMP)
• Designed to support code splitting to reduce deployed application size

Note: NextAuth is not associated with Next.js or Vercel.

Getting Started

NextAuth supports both SQL and Document databases out of the box.

There are predefined models for Users and Sessions, which you can use (or extend or replace with your own models/schemas).

Server

To add next-auth to a project, create a file to handle authentication requests at pages/api/auth/[...slug.js]:

import NextAuth from 'next-auth'
import Providers from 'next-auth/providers'
import Adapters from 'next-auth/adapters'

// Database options - the default adapter is TypeORM
// See https://github.com/typeorm/typeorm/blob/master/docs/using-ormconfig.md
const database = {
  type: 'sqlite',
  database: ':memory:',
}

// NextAuth Options
const options = {
  site: process.env.SITE || 'http://localhost:3000',
  providers: [
    Providers.Twitter({
      clientId: process.env.TWITTER_ID,
      clientSecret: process.env.TWITTER_SECRET,
    }),
    Providers.Google({
      clientId: process.env.GOOGLE_ID,
      clientSecret: process.env.GOOGLE_SECRET
    }),
    Providers.GitHub({
      clientId: process.env.GITHUB_ID,
      clientSecret: process.env.GITHUB_SECRET
    }),
  ],
  adapter: Adapters.Default(database)
}

export default (req, res) => NextAuth(req, res, options)

All requests to pages/api/auth/* (signin, callback, signout, etc) will now be automatically handed by NextAuth.

Note: Your project will need an NPM module suitable for your database installed (e.g. npm i sqlite3).

Client

You can now use the useSession() hook to see if a user is signed in!

import NextAuth from 'next-auth'

export default () => {
  const [session, loading] = NextAuth.useSession()

  return <>
    {loading && <p>Checking session…</p>}
    {!loading && session && <p>Signed in as {session.user.name || session.user.email}.</p>}
    {!loading && !session && <p><a href="/api/auth/signin">Sign in here</p>}
  </>
}

This is all the code you need to add support for signing in to a project!

Adding to _app.js

While calling useSession() like this will work perfectly well, it will do network request to get the session in each component you use it in. To reduce network load and improve performance, you can wrap your component tree in our Provider, which will make useSession() use React Context instead.

You can use this Provider on specific pages or add it to all by adding to your pages/_app.js (Next.js docs for _app.js):

import NextAuth from 'next-auth'

export default ({ Component, pageProps }) => {
  return (
    <NextAuth.Provider>
      <Component {...pageProps} />
    </NextAuth.Provider>
  )
}

Server Side Rendering

Authentication when Server Side Rendering is also supported with session(), which can be called client or server side:

import NextAuth from 'next-auth/client'

export default ({ session }) => <>
  {session && <p>Signed in as {session.user.name || session.user.email}.</p>}
  {!session && <p><a href="/api/auth/signin">Sign in here</a></p>}
</>

export async function getInitialProps({req}) {
  const session = await NextAuth.session({req})
  return {
    session
  }
}

You can use this method and the useSession() hook together - the hook can be pre-populated with the session object from the server side call, so that it is avalible immediately when the page is loaded, and updated client side when the page is viewed in the browser.

You can call NextAuth.session() function in client side JavaScript, without needing to pass a req object - the req object is only needed when calling the function from getServerSideProps or getInitialProps.

Configuration

Configuration options are passed to NextAuth when initalizing it (in your /api/ route).

The only things you will probably need to configure are your site name (e.g. 'http://www.example.com'), which should be set explicitly for security reasons, a list of authentication services (Twitter, Facebook, Google, etc) and a database adapter.

An "Adapter" in NextAuth is the thing that connects your application to whatever database / backend system you want to use to store data for user accounts, sessions, etc.

NextAuth comes with a default adapter that uses TypeORM so that it can be be used with many different databases without any configuration, you simply add the database driver you want to use to your project and tell NextAuth to use it.

If you have an existing database / user management system or want to use a database that isn't supported out of the box you can create and pass your own adapter to handle actions like createAccount, deleteAccount, (etc).

Simple Example

This is an example of how to use an SQLite in memory database, which can be useful for development and testing, and to check everything is working:

1. Install the database driver as a dependancy in the usual way - e.g. npm i sqlite3
2. Pass a TypeORM configuration object when calling NextAuth() in your API route.

e.g.

adapter: Adapters.Default({
  type: 'sqlite',
  database: ':memory:'
}),

You can pass database credentials securely, using environment variables for options. See the TypeORM configuration documentation for more details about supported options.

Supported Databases

The following databases are supported by the default adapter:

• cordova
• expo
• mariadb
• mongodb
• mssql
• mysql
• oracle
• postgres
• sqlite
• sqljs
• react-native

Appropriate tables / collections for Users, Sessions (etc) will be created automatically.

You can customize, extend or replace the models by passing additional options to the Adapters.Default() function.

If you are using a database that is not supported out of the box - or if you want to use NextAuth with an existing database (or have a more complex setup, with accounts and sessions spread across different systems - you can pass your own methods to be called for user and session creation / deletion (etc).

Important! Supported databases and models/scehams subject to change before release.

Customization

NextAuth automatically creates simple, unbranded authentication pages for handling Sign in, Email Verification, callbacks, etc.

The options displayed are generated based on the configuration supplied.

You can create custom authentication pages if you would like to customize the experience.

This documentation will be updated closer to release.