request('https://www.reddit.com/r/proceduralgeneration/about.json')

  .then(x => {

  console.log('Response length: ', x.length, x.substring(0, 100) + '...');

}).catch((err) => {

  console.log('Failed response: ', err);

})

function request(url, options) {

  if (!options) options = {};

  return new Promise(download);

​

  function download(resolve, reject) {

    var req = new XMLHttpRequest();

​

    if (typeof options.progress === 'function') {

      req.addEventListener("progress", updateProgress, false);

    }

​

    req.addEventListener("load", transferComplete, false);

    req.addEventListener("error", transferFailed, false);

    req.addEventListener("abort", transferCanceled, false);

    req.open('GET', url);

​

    if (options.responseType) {

      req.responseType = options.responseType;

    }

​

    req.send(null);

​

    function updateProgress(e) {

      if (e.lengthComputable) {

        options.progress({

          loaded: e.loaded,

          total: e.total,

          percent: e.loaded / e.total

        });

      }

    }

​

    function transferComplete() {

      if (req.status !== 200) {

        reject("Unexpected status code ".concat(req.status, " when calling ").concat(url));

        return;

      }

​

      var response = req.response;

​

      if (options.responseType === 'json' && typeof response === 'string') {

        // IE

        response = JSON.parse(response);

      }

​

      resolve(response);

    }

​

    function transferFailed() {

      reject("Failed to download ".concat(url));

    }

​

    function transferCanceled() {

      reject("Cancelled download of ".concat(url));

    }

  }

}