templates/sitemap.gsp

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
<!-- sort by uri to avoid generating spurious changes -->
<%published_content.toSorted{ it.uri }.each {content -> %>
    <url>
    	<loc>${config.site_host}/${content.uri}</loc>
    	<lastmod>${content.date.format("yyyy-MM-dd")}</lastmod>
    </url>
<%}%>
</urlset>