Extend ember-simple-auth-token to check for more information

token.js

import Ember from 'ember';
import Base from 'ember-simple-auth-token/authenticators/token';

export default Base.extend({
  authenticate(credentials, headers) {
    return new Ember.RSVP.Promise((resolve, reject) => {
      const data = this.getAuthenticateData(credentials);

      this.makeRequest(data, headers).then(response => {
        if (response.data && response.data.role === 'admin') {
          Ember.run(() => {
            resolve(this.getResponseData(response));
          });
        } else {
          Ember.run(() => { reject(new Error('Unauthorised!')); });
        }
      }, xhr => {
        Ember.run(() => { reject(xhr.responseJSON || xhr.responseText); });
      });
    });
  }
});

FYI, the file can be placed inside a new folder called authenticators inside the app folder for an Ember project, i.e. app > authenticators > token.js