Google Apps Script polyfills

GASPolyfills.js

function fetch(url,options2) {
  if (options2) {
    if (options2.body) {
      options2.payload = options2.body.toString("binary");
      options2.body = undefined;
    }
  }
  return new Promise(function (resolve, reject) {
    try {
      var data = UrlFetchApp.fetch(url, options2);
    } catch(e) {console.log(e.message)}
    resolve({
      headers:data.headers,
      text:function(){return data.getContentText()}
    });
  });
}