disqus-embed.php

<?php
/**
 * Plugin Name: WP Disqus Embed
 * Plugin URI: https://imaginarymedia.com.au/2015/02/11/wordpress-plugin-to-embed-disqus/
 * Description: A plugin to add Disqus embedding support via shortcode
 * Version: 0.1
 * Author: Imaginary Media
 * Author URI: https://imaginarymedia.com.au/
 * License: GPL2
 */

/*  Copyright 2015 Imaginary Media (email : support@imaginarymedia.com.au)

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License, version 2, as 
  published by the Free Software Foundation.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

if ( !defined( 'ABSPATH' ) ) exit;

// Create Disqus Shortcode
function disqus_embed($atts, $content = null) {
  extract(shortcode_atts(array("shortname" => ''), $atts));
  if ( $shortname != '') {
    $html =  '<div id="disqus_thread"></div>
              <script>
                  (function() {
                      var dsq = document.createElement("script");
                      dsq.async = true;
                      dsq.src = "//' . $shortname . '.disqus.com/embed.js";
                      (document.getElementsByTagName("head")[0] || document.getElementsByTagName("body")[0]).appendChild(dsq);
                  })();
              </script>';
    return $html;
  }
}
add_shortcode('disqus-comments', 'disqus_embed');

?>