Blob file download in Angular.js using $resource Part 2

gistfile2.js

/* global Blob */

(function () {
  'use strict';

  angular
    .module('app')
    .factory('Email', Email);

  function Email($resource) {
    var url = 'emails/'
      , EmailBase
      , xlsxContentType = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';

    EmailBase = $resource(url + ':emailId', {emailId: '@id'}, {
      getFile: {
        method: 'GET',
        url: url + ':emailId/files/:fileName',
        params: {
          emailId: '@id',
          fileName: '@fileName'
        },
        headers: {
          accept: xlsxContentType
        },
        responseType: 'arraybuffer',
        cache: false,
        transformResponse: function (data) {
          return {
            response: new Blob([data], {type: xlsxContentType})
          };
        }
      }
    });

    return EmailBase;
  }
}());