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Using Credentials provider with a custom backend in NextAuth.js!

Twisha on January 22, 2021

Hello! NextAuth is a great choice when it comes to adding authentication to your next.js app. And it's easy to see why, with it's vast coverage of ...

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Shubham Jaswal • Feb 24 '21

you can also set redirect = false and catch response from signIn function :

const res = await signIn('credentials',
      {
        email,
        password,
        callbackUrl: `${window.location.origin}/account_page` 
        redirect: false,
      }
    )
if (res?.error) handleError(res.error)
if (res.url) router.push(res.url);

signIn return a Promise which has following structure :

{
    error: string || undefined,
    status: number,
    ok: boolean,
    url: url || null
}

you can check more on next-auth.js.org/getting-started/c...

Twisha • Mar 4 '21

Cool! Happy to see it has been added as a feature. Thanks for the update :)

Juanda Martínez • May 27 '21

Thank you so much! I hated that the function reloaded the page every time I submit the form

brianwachira • Mar 30 '21

How does this work?
I have followed your example and am not getting any response in login page

Austin Webb • Aug 21 '21

You are not getting a response because the user isn't being set properly. The following code is able to handle Credentials (user & pass) and Providers auth, while setting jwt and session correctly.

callbacks: {
    jwt: async (token, user) => {
      if (user) {
        token.jwt = user.jwt;
        token.user = user.user;
        token.accessToken = user?.accessToken;
      }
      return Promise.resolve(token);
    },
    session: async (session, token) => {
      session.jwt = token.jwt;
      session.accessToken = token.accessToken ? token.accessToken :
      session.user = token.user ? token.user : session.user; 
      return Promise.resolve(session);
    },
},

David Cruz • Jun 11 '21 • Edited

Hi guys, if you need the token in an axios request, do it like this!

mnengwa • Feb 2 '21

Hi guys, the article has gotten me as far as a successful authentication, for which am grateful. However, I am unable to get the session data using getSession() or useSession() client-side for which they both return null. What are the possible causes of the bug/issue?

Twisha • Feb 3 '21 • Edited

Have you added the Provider in your _app.js ?

import { Provider } from 'next-auth/client'

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

HamidReza Ghafoori • Apr 9 '21

for me it returns undefined.
Did you solve your problem? If yes, can you explain me how?

Lucas • Jan 30 '21

I would be interested in the HTML parts as well! do you have a zip of the shell project? I'm new to building React and Next applications from the ground up and find that most tutorials omit important details, making it very difficult to figure out what they are

Twisha • Feb 2 '21

Sure thing. I'll add the HTML part soon

Bharath Radhakrishnan • Jun 5 '21

Hello Twisha, I came here after one full days googling. I wanted to create a social media sign up button for a nextjs app with with what you call a custom laravel backend. The usage of ' pages/api/[..nextauth].js ' made me asking, where are they even using the custom backend .
So Just to confirm, even you have a custom backend you have to use pages/api feature in the app and define your auth providers there and call the custom backend api's from there right ?

Twisha • Jun 7 '21

Hey Bharath,

If you are using a third party provider for authentication i.e Google, Facebook, Apple, Twitter etc. you don't need a custom backend as everything will be handled by nextauth.js.

If instead you want to use email-passsword login where the credentials are sent to your custom backend (in this case I'm assuming your Laravel app) then you can use the Credentials provider and configure it as it is explained in the article.

For third party provider logins (google, facebook, twitter etc.) nextauth has good documentation. For example this one is for Google -> next-auth.js.org/providers/google

Overall all the configurations for next-auth is in the pages/api/[..nextauth].js file.

Hope it answers your question :)

Bharath Radhakrishnan • Jun 8 '21

What I actually wanted was to save the username, email ... fields after the google / signup to my own database. I think I figured it out. I am using the callbacks options inside the [...nextauth].js to call my api to pass username and email to my backend to store in my db.

Twisha • Jun 8 '21

Ah okay I see what you mean, thanks for sharing your solution :)

Shadee Merhi • Jul 27 '21

Hi there! Thank you for this very helpful article. I understand the login process, but how would you go about creating a custom registration page? Would you have to use the same 'authorize' callback that would have to hit different API endpoints (/login, /signup)? I would love to hear your thoughts on this :)

Brhane Giday • Oct 6 '22

Please find this link.
dev.to/ekrresa/authenticating-with...

Élisson Michael • May 7 '21

Thanks for sharing this.

Twisha • May 10 '21

Glad it helped! :)

Vlad Ilie • Nov 15 '21

Hi Twisha! Great article, thanks for the tips!

I'm wondering if there is a possibility to implement a OTP Login with NextAuth. I can't find anything on the internet 🤔 Do you have some advices?

Thank you! 🎩

Twisha • Dec 20 '21

Thanks Vlăduț Ilie !

Unfortunately I have not explored that option with NextAuth yet :(

Hope you find a useful solution soon :)

Dani • May 18 '21

Muy útil ... mucha gracias!

Twisha • May 25 '21

Glad it's helpful :)

mnengwa • Feb 1 '21

Hi Twisha, nice article. However the file to configure the providers should be pages/api/auth/[...nextauth].js NOT pages/api/auth/[...next-auth].js