Merge remote-tracking branch 'upstream/master' into brian-qpid-transport

kombu/transport/mongodb.py

@@ -34,9 +34,9 @@ class BroadcastCursor(object):
     """Cursor for broadcast queues."""
 
     def __init__(self, cursor):
-        # Fast forward the cursor past old events
+        self._cursor = cursor
-        self._cursor = cursor.skip(cursor.count())
+
-        self._offset = cursor.count()
+        self.purge(rewind=False)
 
     def get_size(self):
         return self._cursor.count() - self._offset
@@ -44,15 +44,33 @@ class BroadcastCursor(object):
     def close(self):
         self._cursor.close()
 
-    def purge(self):
+    def purge(self, rewind=True):
-        self._cursor.rewind()
+        if rewind:
-        self._cursor = self._cursor.skip(self._cursor.count())
+            self._cursor.rewind()
+
+        # Fast forward the cursor past old events
+        self._offset = self._cursor.count()
+        self._cursor = self._cursor.skip(self._offset)
 
     def __iter__(self):
         return self
 
     def next(self):
-        msg = next(self._cursor)
+        while True:
+            try:
+                msg = next(self._cursor)
+            except pymongo.errors.OperationFailure, e:
+                # In some cases tailed cursor can become invalid
+                # and have to be reinitalized
+                if 'not valid at server' in e.message:
+                    self.purge()
+
+                    continue
+
+                raise
+            else:
+                break
+
         self._offset += 1
 
         return msg