Jekyll include file to integrate disqus comments.

disqus.html

{% if site.disqus_short_name and page.comments != false %}
<div id="disqus_thread"></div>
<script>
 var disqus_shortname = '{{ site.disqus_short_name }}';
 var disqus_config = function () {
   // _config.yml should define the site's URL
   this.page.url = '{{ site.url }}{{ page.url }}';
   // Using an optional disqus_identifier variable, or the site.url + page.id combination
   this.page.identifier = '{% if page.disqus_identifier %}{{ page.disqus_identifier}}{% else %}{{ site.url }}{{ page.id }}{% endif %}';
 };
 (function() {
   var d = document, s = d.createElement('script');
   s.src = '//' + disqus_shortname + '.disqus.com/embed.js';     
   s.setAttribute('data-timestamp', +new Date());
   (d.head || d.body).appendChild(s);
 })();
</script>
<noscript>Please enable JavaScript to view the <a href="https://disqus.com/?ref_noscript" rel="nofollow">comments powered by Disqus.</a></noscript>
{% endif %}

Refer also to this guide https://poanchen.github.io/blog/2017/07/27/how-to-add-disqus-to-your-jekyll-site