diff -r f4a4556f23da -r 2eb06486273a server/sources/datafeed.py
--- a/server/sources/datafeed.py	Thu Jan 22 10:43:24 2015 +0100
+++ b/server/sources/datafeed.py	Wed Jan 07 16:22:27 2015 +0100
@@ -319,6 +319,8 @@
         * handle file:// URL
         * other will be considered as plain content, useful for testing purpose
         """
+        if headers is None:
+            headers = {}
         if url.startswith('http'):
             url = self.normalize_url(url)
             if data: