--- a/commitwatcher/agent.py	Fri Sep 27 14:23:53 2013 -0700
+++ b/commitwatcher/agent.py	Sat Sep 28 05:10:14 2013 -0700
@@ -3,6 +3,7 @@
 """
 
 import feedparser
+from abc import abstractmethod
 from .commit import Commit
 from .store import MemoryStore
 
@@ -38,10 +39,30 @@
         feed = feedparser.parse(self.feed())
         for entry in feed['entries']:
 
-            # get paths from diff
             link = entry['link']
-            print link
             files = self.files(link)
             # TODO
 
             # TODO            commit = Commit()
+
+class FeedAgentDiff(FeedAgent):
+    """read files from diff"""
+
+    def diff_url(self, link):
+        """
+        returns diff_url from revision link:
+
+        >>> diff_url('http://hg.mozilla.org/mozilla-central/rev/4e1a3919e741')
+        'http://hg.mozilla.org/mozilla-central/raw-rev/4e1a3919e741'
+        """
+        return '/raw-rev/'.join(link.rsplit('/rev/', 1))
+
+    def files(self, revision):
+        """
+        revision -- revision link
+        """
+
+        raw_rev = self.diff_url(revision)
+        print raw_rev
+
+        # get paths from diff