Auth0 rule for JWT Hasura roles

rule.js

function (user, context, callback) {
  // console.log('context', context);

  const namespace = "https://hasura.io/jwt/claims";
  const roles = (context.authorization || {}).roles || [];
  const claims = {
    'x-hasura-default-role': 'user',
    'x-hasura-allowed-roles': [
      'anonymous',
      'user',
      ...roles,
    ],
    'x-hasura-user-id': user.user_id
  };
  context.accessToken[namespace] = claims;
  context.idToken[namespace] = claims;

  // console.log('claims', claims);
  callback(null, user, context);
}

Sources:
Auth0 Docs, Rules with Authorization: Add user roles to tokens
Hasura Docs, Auth0 JWT Integration with Hasura GraphQL engine: Configure Auth0 Rules & Callback URLs