Adds button for serving the current repository as a static site using rawgit. Useful for viewing react/angular demo projects

rawgit-button.user.js

// ==UserScript==
// @name         Raw Git Button
// @description  Open rawgit.com on the current repo serving its files
// @author       nkmathew
// @namespace    http://nkmathew.net
// @require      https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js
// @include      /https:\/\/github.com\/[^/]+\/[^/]+[/]{0,1}$/
// @version      0.1.0
// @grant        GM_getValue
// @grant        GM_setValue
// ==/UserScript==

var pageUrl = location.href.replace(/github.com/, 'rawgit.com');
if (pageUrl.endsWith('/')) {
  pageUrl += 'master/';
} else {
  pageUrl += '/master/';
}

// Try to handle cases where the web root folder is in a folder called 'public'
var root = '';
var indexHtmlExists = false;
var htmlFiles = [];
jQuery('.content .css-truncate a').each(function () {
  var fname = this.text;
  if (fname === 'public') {
    root = 'public/';
  } else if (fname === 'index.html') {
    indexHtmlExists = true;
  } else if (fname.endsWith('html') || fname.endsWith('htm')) {
    htmlFiles.push(fname);
  }
});

// Find a default html file to serve in the root folder instead of hitting a 404
if (indexHtmlExists) {
  root = '';
} else {
  if (htmlFiles.length) {
    root = htmlFiles[htmlFiles.length - 1];
  }
}

var content =
  '<li class="header-nav-item" id="rawgit-item">' +
  '  <a class="header-nav-link" id="rawgit-link" href="' + pageUrl + root +
    '">Raw Git</a>' +
  '</li>';

jQuery(content).insertAfter(jQuery('.header-nav.float-left'));
jQuery('#rawgit-item').css('list-style-type', 'none');
jQuery('#rawgit-link').css('color', 'rgb(65, 131, 196)');