From 597b2454ec9cf6744e65bd96737b57849ead8179 Mon Sep 17 00:00:00 2001
From: Adam Sampson <ats@offog.org>
Date: Wed, 7 May 2003 01:08:21 +0000
Subject: [PATCH] Fix an interesting bug: if a feed hadn't changed for long
 enough that the articles from it had been expired, then when it *did* change
 those articles would be shown again. The fix is to only do expiry on feeds
 that have received some items this update. (Which also means that feeds that
 never update will never expire, which is probably a desirable feature.)

---
 rawdoglib/rawdog.py | 41 +++++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/rawdoglib/rawdog.py b/rawdoglib/rawdog.py
index aec0d65..9853ff9 100644
--- a/rawdoglib/rawdog.py
+++ b/rawdoglib/rawdog.py
@@ -39,8 +39,11 @@ class Feed:
 		self.last_update = 0
 	
 	def update(self, articles, now, force = 0):
+		"""Fetch articles from a feed and add them to the collection.
+		Returns 1 if any articles were read, 0 otherwise."""
+
 		if not force and (now - self.last_update) < (self.period * 60):
-			return
+			return 0
 		self.last_update = now
 
 		try:
@@ -48,12 +51,13 @@ class Feed:
 				self.modified,	"rawdog/" + VERSION)
 		except:
 			print "Error fetching " + self.url
-			return
+			return 0
 
 		self.etag = p.get("etag")
 		self.modified = p.get("modified")
 		# In the event that the feed hasn't changed, then both channel
-		# and feed will be empty.
+		# and feed will be empty. In this case we return 0 so that
+		# we know not to expire articles that came from this feed.
 
 		channel = p["channel"]
 		if channel.has_key("title"):
@@ -62,6 +66,7 @@ class Feed:
 			self.link = channel["link"]
 
 		feed = self.url
+		seen_items = 0
 		for item in p["items"]:
 			title = item.get("title")
 			link = item.get("link")
@@ -76,6 +81,9 @@ class Feed:
 				articles[article.hash].last_seen = now
 			else:
 				articles[article.hash] = article
+			seen_items = 1
+
+		return seen_items
 
 	def get_html_name(self):
 		if self.title is not None:
@@ -233,18 +241,27 @@ class Rawdog(Persistable):
 		for url in self.feeds.keys():
 			if not seenfeeds.has_key(url):
 				del self.feeds[url]
-	
-		if feedurl is None:	
-			for url in self.feeds.keys():	
-				self.feeds[url].update(self.articles, now)
+
+		if feedurl is None:
+			update_feeds = self.feeds.keys()
+			force = 0
+		elif self.feeds.has_key(feedurl):
+			update_feeds = [feedurl]
+			force = 1
 		else:
-			if self.feeds.has_key(feedurl):
-				self.feeds[feedurl].update(self.articles, now, 1)
-			else:
-				print "No such feed: " + feedurl
+			print "No such feed: " + feedurl
+			update_feeds = []
+	
+		seen_some_items = {}
+		for url in update_feeds:
+			if self.feeds[url].update(self.articles, now, force):
+				seen_some_items[url] = 1
 
 		for key in self.articles.keys():
-			if self.articles[key].can_expire(now) or not self.feeds.has_key(self.articles[key].feed):
+			article = self.articles[key]
+			if ((not self.feeds.has_key(article.feed))
+			    or (seen_some_items.has_key(article.feed)
+			        and article.can_expire(now))):
 				del self.articles[key]
 
 		self.modified()
-- 
2.35.1