simplify the expected feed structure

I don't think there's any need for a million directories, on second
thought, so just put YYMMDD prefixed files in the feed/ directory

Signed-off-by: Brian S. Stephan <bss@incorporeal.org>

incorporealcms/feed.py

@@ -1,8 +1,8 @@
 """Generate Atom and RSS feeds based on content in a blog-ish location.
 
-This parses a special root directory, feed/, for feed/YYYY/MM/DD/file files,
+This parses a special root directory, feed/, for YYYYMMDD-foo.md files,
 and combines them into an Atom or RSS feed. These files *should* be symlinks
-to the real pages, which may mirror the same YYYY/MM/DD/file naming scheme
+to the real pages, which may mirror the same YYYYMMDD-foo.md file naming scheme
 under pages/ (which may make sense for a blog) if they want, but could just
 as well be pages/foo content.
 
@@ -68,6 +68,6 @@ def serve_feed(feed_type):
 
 def _generate_feed_id(feed_entry_path):
     """For a relative file path, generate the Atom/RSS feed ID for it."""
-    date = re.sub(r'.*/(\d+)/(\d+)/(\d+).*', r'\1-\2-\3', feed_entry_path)
+    date = re.sub(r'.*(\d{4})(\d{2})(\d{2}).*', r'\1-\2-\3', feed_entry_path)
     cleaned = feed_entry_path.replace('#', '/').replace('feed/', '', 1).replace(app.instance_path, '')
     return f'tag:{app.config["DOMAIN_NAME"]},{date}:{cleaned}'

incorporealcms/templates/base.html

@@ -9,6 +9,8 @@
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <link rel="stylesheet" href="{{ user_style }}">
 <link rel="icon" href="{% if config.FAVICON %}{{ config.FAVICON }}{% else %}{{ url_for('static', filename='img/favicon.png') }}{% endif %}">
+<link rel="alternate" type="application/atom+xml" href="/feed/atom" />
+<link rel="alternate" type="application/rss+xml" href="/feed/rss" />
 
 <div {% block site_class %}class="site-wrap site-wrap-normal-width"{% endblock %}>
     {% block header %}