Rewrite links leaving site

external-links.js

const $ = require('jquery');

$('a').each(function() {

  var $this = $(this);

  var url = $this.attr('href');
  var redir = `//${location.host}/`;
  var href = /http(s|):\/\//i;
  var hrefPat = new RegExp(href);

  if (hrefPat.test(url) && !!!$this.attr('data-allowext')) {
    
    var www = /(www|)\.example\.com/i;
    var wwwPat = new RegExp(www);

    if (!wwwPat.test(url)) {
      var newurl = redir + 'leaving-example/' + 
        '?dest=' + encodeURIComponent(url.toString()) + 
        '&ref=' + encodeURIComponent(location.pathname)
      $this.attr('href', newurl);
    }
  }
});