<?xml version=“1.0” encoding=“UTF-8”?>

{% assign timeframe = 172800 %}
{% assign posts = site.posts | where_exp:'doc','doc.sitemap != false' %}
{% for post in posts %}
  {% assign post_in_seconds = post.date | date: "%s" | plus: 0 %}
  {% assign recent_posts = "now" | date: "%s" | minus: timeframe  %}
  {% if post_in_seconds > recent_posts %}
  <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
      xmlns:news="http://www.google.com/schemas/sitemap-news/0.9">
    <url>
      <loc>{{ post.url | replace:'/index.html','/' | absolute_url | xml_escape }}</loc>

      <news:news>
        <news:publication>
          <news:name>{{site.publisher}}</news:name>
          <news:language>en</news:language>
        </news:publication>
        <news:publication_date>{{ post.date | date_to_xmlschema }}</news:publication_date>
        <news:title>{{ post.title }}</news:title>
      </news:news>
    </url>
  </urlset>
  {% endif %}
{% endfor %}