diff -rN -u old-trunk/buildbot/changes/hgpoller.py new-trunk/buildbot/changes/hgpoller.py
--- old-trunk/buildbot/changes/hgpoller.py	1969-12-31 19:00:00.000000000 -0500
+++ new-trunk/buildbot/changes/hgpoller.py	2007-08-03 02:20:40.000000000 -0400
@@ -0,0 +1,113 @@
+import time
+import rfc822
+from urllib import urlopen
+from xml.dom import minidom, Node
+
+from twisted.python import log, failure
+from twisted.internet import defer, reactor
+from twisted.internet.task import LoopingCall
+
+from buildbot.changes import base, changes
+
+class HgPoller(base.ChangeSource):
+    """This source will poll a Mercurial server over HTTP using
+    the built-in RSS feed for changes and submit them to the
+    change master."""
+
+    compare_attrs = ['hgURL', 'branch', 'pollInterval']
+    parent = None
+    loop = None
+    volatile = ['loop']
+    working = False
+    
+    def __init__(self, hgURL, branch, pollInterval=30):
+        """
+        @type   hgURL:          string
+        @param  hgURL:          The base URL of the Hg repo
+                                (e.g. http://hg.mozilla.org/)
+        @type   branch:         string
+        @param  branch:         The branch to check (e.g. mozilla-central)
+        @type   pollInterval:   int
+        @param  pollInterval:   The time (in seconds) between queries for
+                                changes
+        """
+        
+        self.hgURL = hgURL
+        self.branch = branch
+        self.pollInterval = pollInterval
+        self.lastChange = time.time()
+        self.lastPoll = time.time()
+
+    def startService(self):
+        self.loop = LoopingCall(self.poll)
+        base.ChangeSource.startService(self)
+        reactor.callLater(0, self.loop.start, self.pollInterval)
+
+    def stopService(self):
+        self.loop.stop()
+        return base.ChangeSource.stopService(self)
+    
+    def describe(self):
+        return "Getting changes from the Mercurial repo at %s%s" % \
+               (self.hgURL, self.branch)
+    
+    def poll(self):
+        if self.working:
+            log.msg("Not polling because last poll is still working")
+        else:
+            self.working = True
+            d = self._get_changes()
+            d.addCallback(self._process_changes)
+            d.addCallbacks(self._finished_ok, self._finished_failure)
+
+    def _finished_ok(self, res):
+        assert self.working
+        self.working = False
+
+        return res
+
+    def _finished_failure(self, res):
+        log.msg("Hg poll failed: %s" % res)
+        assert self.working
+        self.working = False
+        return None
+
+    def _make_url(self):
+        return "%s%s/?rss-log" % (self.hgURL, self.branch)
+    
+    def _get_changes(self):
+        url = self._make_url()
+        log.msg("Polling Hg server at %s" % url)
+        
+        self.lastPoll = time.time()
+        return defer.maybeDeferred(urlopen, url)
+
+    def _parse_changes(self, query):
+        dom = minidom.parseString(query.read())
+        items = dom.getElementsByTagName("item")
+        changes = []
+        for i in items:
+            d = dict()
+            for k in ["description", "link", "author", "pubDate"]:
+                d[k] = i.getElementsByTagName(k)[0].firstChild.wholeText
+            # strip out HTML newlines
+            d["description"] = d["description"].replace("<br/>","")
+            # need to parse date with timezone, and turn into a UTC timestamp
+            d["pubDate"] = rfc822.mktime_tz(rfc822.parsedate_tz(d["pubDate"]) )
+            changes.append(d)
+        changes = [c for c in changes if c["pubDate"] > self.lastChange]
+        changes.reverse() # want t hem in reverse chronological order
+        return changes
+    
+    def _process_changes(self, query):
+        change_list = self._parse_changes(query)
+        for change in change_list:
+            c = changes.Change(who = change["author"],
+                               files = [], # sucks
+                               comments = change["description"],
+                               when = change["pubDate"],
+                               branch = self.branch)
+            self.parent.addChange(c)
+        self.lastChange = max(self.lastPoll, *[c["pubDate"] for c in
+                                                   change_list])
+