debian-mirror-gitlab/app/assets/javascripts/lib/utils/users_cache.js

import Api from '../../api';
import Cache from './cache';

class UsersCache extends Cache {
  retrieve(username) {
    if (this.hasData(username)) {
      return Promise.resolve(this.get(username));
    }

    return Api.users('', { username }).then(({ data }) => {
      if (!data.length) {
        throw new Error(`User "${username}" could not be found!`);
      }

      if (data.length > 1) {
        throw new Error(`Expected username "${username}" to be unique!`);
      }

      const user = data[0];
      this.internalStorage[username] = user;
      return user;
    });
    // missing catch is intentional, error handling depends on use case
  }
}

export default new UsersCache();