Very simple link expiration for React Aps

App.js

if(window.location.search.indexOf('key') > -1 )
  {
    try {
      // Could probably do this better but I'm being lazy
      const linkKey = window.location.href.toString().split('=')[1] 
      // Side effect of being lazy means I have to add back the 2 == at the end of the string I just split
      var bytes  = CryptoJS.AES.decrypt(linkKey + '==', KEY);
      var originalText = bytes.toString(CryptoJS.enc.Utf8);
      passUser = moment(originalText).valueOf() > moment().valueOf()
    } catch (error) {
      passUser = false;
    }
  }
  if(!passUser) {
    return <NoAccess />
  } else {
    <Access />
  }

GenLink.js

import React from "react";
import CryptoJS from "crypto-js";
import moment from "moment/moment";
const KEY = 'somekey'
export default _ => {
    var ciphertext = CryptoJS.AES.encrypt(moment().add(1, 'days').endOf('day').toString(), KEY).toString();
    var bytes  = CryptoJS.AES.decrypt(ciphertext, KEY);
    var originalText = bytes.toString(CryptoJS.enc.Utf8);
    var isLinkValid = moment(originalText).valueOf() > moment().valueOf()
    const href = `${window.location.protocol}//${window.location.host}?key=${ciphertext}`;
    return(<pre className="my-8">{href}</pre>)
}

If you need a down and dirty link expiration this code works just fine. However, someone savvy could reverse engineer it from inspecting the code. DO NOT USE FOR SENSITIVE INFO!