Hello, I have a nextjs app with nextauth.js and a mongodpadapter which writes all new sign ins to my database. This part is working without any problems. Now what I need is to be able to give my users roles, i need a Customer, Customer Service Rep and Admin role.

My idea is to extend the MongoDBAdapter making a new field in user called "role" which defaults to "customer". I found some stuff online aswell as on GPT but I can't get it to work. Below is this code that I currently have, which is supposed to implement a callback which gives a new role field.

I'm looking for either a way to make this role populate in my DB, but im also open to other suggestions for how to store user role. Thanks for the help.

import NextAuth from "next-auth"
import GithubProvider from "next-auth/providers/github"
import GoogleProvider from "next-auth/providers/google"
import { MongoDBAdapter } from "@auth/mongodb-adapter"
import clientPromise from "./lib/mongodb"

//auth options here

export default NextAuth({
    ...authOptions, // Spread the authOptions object
    adapter: MongoDBAdapter(clientPromise), // Pass the clientPromise directly to MongoDBAdapter
    callbacks: {
        async session({ session, user }) {
          // Add the user's role to the session object
          session.user.role = user.role ?? "customer";
          return session;
        },
        async createUser(user) {
            console.log("createUser", user)
          // Here, you modify the user object to include the role
          // No need to manually insert the user into the database; NextAuth and the adapter handle it
          user.role = "customer";
          return user;
        }
    },
})