Ensure feed GUIDs are unchanging and unique

Implement 'tag:' style URIs for the GUID field on our RSS feeds. This
ensures new package updates show up as new, and we aren't jumping back
and forth between generated GUIDs having 'http://' and 'https://'
prefixes.

Much of the work here is to attempt to keep old news GUIDs constant so
we don't once again make everything show up as new in newsreaders.

Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/feeds.py b/feeds.py
index cdba991..d204327 100644
--- a/feeds.py
+++ b/feeds.py
@@ -1,6 +1,7 @@
 import datetime
 from decimal import Decimal, ROUND_HALF_DOWN
 
+from django.contrib.sites.models import Site
 from django.contrib.syndication.views import Feed
 from django.core.cache import cache
 from django.db.models import Q
@@ -97,9 +98,18 @@ class PackageFeed(Feed):
         s += '.'
         return s
 
+    subtitle = description
+
     def items(self, obj):
         return obj['qs']
 
+    def item_guid(self, item):
+        # http://diveintomark.org/archives/2004/05/28/howto-atom-id
+        date = item.last_update
+        return 'tag:%s,%s:%s%s' % (Site.objects.get_current().domain,
+                date.strftime('%Y-%m-%d'), item.get_absolute_url(),
+                date.strftime('%Y%m%d%H%M'))
+
     def item_pubdate(self, item):
         return item.last_update
 
@@ -135,6 +145,7 @@ class NewsFeed(Feed):
     title = 'Arch Linux: Recent news updates'
     link = '/news/'
     description = 'The latest and greatest news from the Arch Linux distribution.'
+    subtitle = description
     title_template = 'feeds/news_title.html'
     description_template = 'feeds/news_description.html'
 
@@ -146,6 +157,9 @@ class NewsFeed(Feed):
         return News.objects.select_related('author').order_by(
                 '-postdate', '-id')[:10]
 
+    def item_guid(self, item):
+        return item.guid
+
     def item_pubdate(self, item):
         return item.postdate