Next.js: Update Auth0 user metadata

.env.local

AUTH0_ISSUER_BASE_URL='https://YOUR_AUTH0_DOMAIN.auth0.com'
AUTH0_SCOPE='openid read:current_user create:current_user_metadata update:current_user_metadata'

[...auth0].js

// api/auth/[...auth0].js
import { handleAuth, handleLogin } from '@auth0/nextjs-auth0';

export default handleAuth({
  async login(req, res) {
    try {
      await handleLogin(req, res, {
        authorizationParams: {
          audience: `${process.env.AUTH0_ISSUER_BASE_URL}/api/v2/`,
          // Need to specify scope here, for some reason nextjs-auth0
          // doesn't automagicallyread the scope variable from process.env
          // like it does with other variables
          scope: process.env.AUTH0_SCOPE,
        },
      });
    } catch (error) {
      res.status(error.status || 400).end(error.message);
    }
  },
});

me.js

// api/private/me.js
import axios from 'axios';
import { withApiAuthRequired, getSession } from '@auth0/nextjs-auth0';
import { ManagementClient } from 'auth0';

const userHandler = async (req, res) => {
  const { body } = req;

  const session = await getSession(req, res);
  const id = session.user.sub;
  const accessToken = session.accessToken;

  try {
    const params = body;

    const currentUserManagementClient = new ManagementClient({
      token: accessToken,
      domain: process.env.AUTH0_ISSUER_BASE_URL.replace('https://', ''),
      scope: process.env.AUTH0_SCOPE,
    });

    const user = await currentUserManagementClient.updateUserMetadata(
      { id },
      params
    );

    res.status(200).json(params);
  } catch (err: any) {
    console.log(err);
    res.status(500).json({ statusCode: 500, message: err.message });
  }
};

export default withApiAuthRequired(userHandler);