supabase/examples/nextjs-with-supabase-auth/pages/api/getUser.js

import { supabase } from '../../utils/initSupabase'

// Example of how to verify and get user data server-side.
const getUser = async (req, res) => {
  const token = req.headers.token

  const { data: user, error } = await supabase.auth.api.getUser(token)

  if (error) return res.status(401).json({ error: error.message })
  return res.status(200).json(user)
}

export default getUser