old_contents: {
    class UsersService {
      create(user) {
        console.log('CREATED!');
        console.log(user);
      }
    }
  
    angular
      .module('meganote.users')
      .service('UsersService', UsersService);
  }
  
new_contents: {
    angular
      .module('meganote.users')
      .service('UsersService', [
        '$http',
        'API_BASE',
        ($http, API_BASE) =>{
  
          class UsersService {
            create(user) {
              return $http.get(API_BASE)
                .then(res => {
                  console.log(res.data);
                });
            }
          }
  
          return new UsersService();
        }
      ]);
  }
  
subject: Refactor sign-up directive to use UsersService