UserStore.js

var mixin = lang.mixin;

var API_URL = 'http://jsonplaceholder.typicode.com';

var UserStore = declare(Store, {
  
  constructor: function() {
    this.apiUrl = API_URL;
    this.headers = {}; // any custom headers here
  },
  
  _request: function(target, options) {
    var def = new Deferred();
    
    options = mixin({
      handleAs: 'json',
      url: this.apiUrl + target,
      method: 'get'
    }, options);
    options.headers = mixin({}, options.headers, this.headers);
    
    esriRequest(options)
      .then(function(results) {
      // normally do any cleanup here
      // if needed
      def.resolve(results);
    })
    .otherwise(function(err) { def.reject(err); });
    
    return def.promise;
  },
  
  get: function(id) {
    if (id == null) { // loose check, 0 could be allowed
      return this.fetch();
    }
    return this._request('/users/' + id);
  },
  
  fetch: function() {
    var queryLog = this.queryLog;
    return new QueryResults(
    this._request('/users')
    .then(function(data) {
      queryLog.map(function(entry) { data = entry.querier(data); });
      return data;
    }));
  }
  
});