From 2e19b657380422b17ffa3aeb761c919d9404464a Mon Sep 17 00:00:00 2001
From: Luke Sneeringer <luke@sneeringer.com>
Date: Tue, 4 Nov 2014 13:51:08 -0600
Subject: [PATCH] Fix for run_task_system

---
 awx/main/queue.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/awx/main/queue.py b/awx/main/queue.py
index 21e84e3112..a543838ad0 100644
--- a/awx/main/queue.py
+++ b/awx/main/queue.py
@@ -52,13 +52,19 @@ class FifoQueue(object):
         """
         self._queue_name = queue_name
 
+    def __len__(self):
+        """Return the length of the Redis list."""
+        return redis.llen(self._queue_name)
+        
     def push(self, value):
         """Push a value onto the right side of the queue."""
         redis.rpush(self._queue_name, json.dumps(value))
 
     def pop(self):
         """Retrieve a value from the left side of the queue."""
-        return json.loads(redis.lpop(self._queue_name))
+        answer = redis.lpop(self._queue_name)
+        if answer:
+            return json.loads(answer)
 
 
 class PubSub(object):