NextJS-Auth0: How can I assign a role on signup with Auth0? - reactjs

Question

Using the library nextjs-auth0 (https://github.com/auth0/nextjs-auth0) I've been trying to make use of the handleAuth hook to grab a query arg to specify which role should be assigned to the user on signup.
An example of what I'm trying to do:
//pages/api/auth/[...auth0].js
const getLoginState = (req, loginOptions) => {
const { role } = req.query;
return { role: role };
};
export default handleAuth({
async login(req, res) {
try {
await handleLogin(req, res, { getLoginState } );
} catch (error) {
res.status(error.status || 500).end(error.message);
}
}
});
The documentation for handleAuth makes it seem like it's possible to do this ( https://auth0.github.io/nextjs-auth0/modules/handlers_login.html#getloginstate )
// from the documentation
const getLoginState = (req, loginOptions) => {
return { basket_id: getBasketId(req) };
};
From that doc - it looks like basket_id is the custom property to be saved against the user "before they visit the Identity Provider to login".
This sounds, to me, that basked_id will be saved somewhere against the users metadata once they've logged in. Is the documentation misleading, or am I misunderstanding?
How can I set the role during (or even slightly after) signup?

Answer 1

I managed to achieve what I wanted with the following Auth0 "rule":
function (user, context, callback) {
const count = context.stats && context.stats.loginsCount ? context.stats.loginsCount : 0;
if (count > 1) {
return callback(null, user, context);
}
const ManagementClient = require('auth0#2.27.0').ManagementClient;
const management = new ManagementClient({
token: auth0.accessToken,
domain: auth0.domain
});
let roles = [context.request.query.role];
const params = { id : user.user_id};
const data = { "roles" : roles};
management.users.assignRoles(params, data, function (err, user) {
if (err) {
// Handle error.
console.log(err);
}
callback(null, user, context);
});
}
Notice that the role is being read in from context.request.query.role. This pulls the query param role key off the login URL which more-or-less works how I wanted it to.
Then forward the role along from the auth in the backend:
const getLoginState = (req, loginOptions) => {
const { role } = req.query;
loginOptions.authorizationParams.role = role;
return { role: role };
};
export default handleAuth({
async login(req, res) {
try {
await handleLogin(req, res, { getLoginState });
} catch (error) {
res.status(error.status || 500).end(error.message);
}
}
});
Notice the loginOptions.authorizationParams.role = role;
So the login link can be set to: /api/auth/login?role=somerole and the rule will pick up the role and set it in the metadata part of the users info.
However: I wasn't able to get this to actually properly set the role on the user but it's enough for me, as it appears in the session.