From 21d267cb112e9030a0f17271fecd052dbe35b50a Mon Sep 17 00:00:00 2001
From: flosch <flori@n-schlachter.de>
Date: Mon, 26 Jul 2010 17:28:59 +0200
Subject: [PATCH] Now order_by() works like queries for referencing deeper
 fields (replacing . with __). old: order_by('mydoc.myattr') / new:
 order_by('mydoc__myattr'). Closes #45

---
 mongoengine/queryset.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mongoengine/queryset.py b/mongoengine/queryset.py
index ffbe5255..0b9218af 100644
--- a/mongoengine/queryset.py
+++ b/mongoengine/queryset.py
@@ -670,11 +670,13 @@ class QuerySet(object):
         """
         key_list = []
         for key in keys:
+            if not key: continue
             direction = pymongo.ASCENDING
             if key[0] == '-':
                 direction = pymongo.DESCENDING
             if key[0] in ('-', '+'):
                 key = key[1:]
+            key = key.replace('__', '.')
             key_list.append((key, direction))
 
         self._ordering = key_list