add lastmod in sitemap

content/templates/jinja2/sitemap.html

@@ -1,16 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
-<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
-
-    {% for p in object.pages_slugs %}
-        <url>
-            <loc>{{ object.domain }}/pages/{{ p }}.html</loc>
-        </url>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xhtml="http://www.w3.org/1999/xhtml">
+{% for url in urlset %}
+  <url>
+    <loc>{{ url.location }}</loc>
+    {% if url.lastmod %}<lastmod>{{ url.lastmod.strftime(url.item.lastmod_format) }}</lastmod>{% endif %}
+    {% if url.changefreq %}<changefreq>{{ url.changefreq }}</changefreq>{% endif %}
+    {% if url.priority %}<priority>{{ url.priority }}</priority>{% endif %}
+    {% for alternate in url.alternates %}
+    <xhtml:link rel="alternate" hreflang="{{ alternate.lang_code }}" href="{{ alternate.location }}"/>
     {% endfor %}
-    {% for p in object.posts_slugs %}
-        <url>
-            <loc>{{ object.domain }}/posts/{{ p }}.html</loc>
-        </url>
-    {% endfor %}
-
-</urlset>
+  </url>
+{% endfor %}
+</urlset>

jssg/models.py

@@ -226,6 +226,7 @@ class Page(Document):
     """A webpage, with a title and some content."""
 
     BASE_DIR = settings.JFME_PAGES_DIRS
+    lastmod_format = settings.JFME_SITEMAP_LASTMOD_DATETIME_FORMAT
 
     def __init__(self, content: str, **metadata) -> None:
         """Create a new page.

jssg/settings.py

@@ -53,6 +53,7 @@
 JFME_TEMPLATES_DIRS = [path / "templates" for path in JFME_CONTENT_DIRS]
 JFME_STATIC_DIRS = [path / "static" for path in JFME_CONTENT_DIRS]
 JFME_NUMBER_OF_POSTS_BY_PAGE = 3
+JFME_SITEMAP_LASTMOD_DATETIME_FORMAT = "%Y-%m-%dT%H:%M:%S%z" # %Y:YYYY, %m:MM, %d:DD, %z:+/-HHMM
 
 #Django sites and sitemap app
 SITE_ID = 1

jssg/sitemaps.py

@@ -3,8 +3,10 @@
 from django.contrib.sites.models import Site
 from jssg.models import Page, Post, PostList
 from django.conf import settings
+from datetime import datetime
 
 class MySitemap(Sitemap) :
+    #Overriding get_url() to specify the domain name
     def get_urls(self, site=None, **kwargs):
         site = Site(domain=settings.JFME_DOMAIN, name=settings.JFME_DOMAIN)
         return super(MySitemap, self).get_urls(site=site, **kwargs)
@@ -23,6 +25,8 @@ def location(self, page) -> str:
             return "/" + page.rel_folder_path + "/" + page.slug + ".html"
         else :
             return "/" + page.slug + ".html"
+    def lastmod(self, post) :
+        return datetime.fromtimestamp(post.path.lstat().st_mtime)
 
 class PostSitemap(MySitemap) :
     def items(self) :
@@ -32,6 +36,8 @@ def location(self, post) -> str:
             return "/posts/article/" + post.rel_folder_path + "/" + post.slug + ".html"
         else :
             return "/posts/articles/" + post.slug + ".html"
+    def lastmod(self, post) :
+        return datetime.fromtimestamp(post.path.lstat().st_mtime)
 
 class PostListSitemap(MySitemap) :
     def items(self) :

jssg/urls.py

@@ -70,7 +70,10 @@
     distill_path(
         "sitemap.xml",
         sitemap,
-        {"sitemaps": {"constant-url": ConstantUrlSitemap, "page": PageSitemap, "posts": PostSitemap, "postlist":PostListSitemap}},
+        {
+            "sitemaps": {"constant-url": ConstantUrlSitemap, "page": PageSitemap, "posts": PostSitemap, "postlist":PostListSitemap}, 
+            "template_name":"sitemap.html"
+        },
         name="django.contrib.sitemaps.views.sitemap",
     )
 ]