From af5f110d376d62c229a2b86f7fd1e573b6168801 Mon Sep 17 00:00:00 2001
From: Tomas Kopecek <tkopecek@redhat.com>
Date: Wed, 10 Jan 2018 14:05:07 +0100
Subject: [PATCH] check for empty header

---
 koji/rpmdiff.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/koji/rpmdiff.py b/koji/rpmdiff.py
index f530da8d..6b92c12b 100755
--- a/koji/rpmdiff.py
+++ b/koji/rpmdiff.py
@@ -224,9 +224,12 @@ class Rpmdiff:
     def kojihash(self, new=False):
         """return hashed data for use in koji"""
         if new:
-            s = json.dumps(self.new_data, sort_keys=True)
+            data = self.new_data
         else:
-            s = json.dumps(self.old_data, sort_keys=True)
+            data = self.old_data
+        if not data:
+            raise ValueError("rpm header data are empty")
+        s = json.dumps(self.old_data, sort_keys=True)
         return hashlib.sha256(s).hexdigest()
 
 def _usage(exit=1):