--- a/connectors/ConnectorBase.py	Fri Feb 01 14:14:13 2019 +0100
+++ b/connectors/ConnectorBase.py	Wed Feb 13 09:41:35 2019 +0100
@@ -9,14 +9,14 @@
 
     #chuncksize = 16384
     chuncksize = 1024*1024
-    def BlobFromFile(self, filepath): 
+    def BlobFromFile(self, filepath, seed):
         s = md5.new()
-        blobID = s.digest()  # empty md5, to support empty blob
+        s.update(seed)
+        blobID = self.SeedBlob(seed)
         with open(filepath, "rb") as f:
-            while True:
+            while blobID == s.digest():
                 chunk = f.read(self.chuncksize) 
                 if len(chunk) == 0: return blobID
                 blobID = self.AppendChunkToBlob(chunk, blobID)
                 s.update(chunk)
-                if blobID != s.digest(): return None