Vanilla Javascript to swap urls for Styles and Scripts

loader.js

// local vs remote hostred url (needed for static storage usually)
const prefix = isLocal() ? '.' : 'http://example.com';
// Stylesheet path
const cssPath = '/assets/styles/css/app.css';
// Script path
const scriptPath = '/assets/scripts/js/app.js';
// HTML tag attributes
const cnfgs = [
  { link: { rel: 'stylesheet', type: 'text/css', href: prefix + cssPath } },
  { script: { src: prefix + scriptPath } }
];

// loop to add the above configuration to the document head
cnfgs.forEach((cnfg) => {
  const [ type ] = Object.keys(cnfg);
  const el = document.createElement(type);
  Object.assign(el, cnfg[ type ]);
  document.head.appendChild(el);
});

function isLocal() { return /localhost/.test(location.hostname); }