From 624223e370f3b5d1e7910f01d03baf541ab6f7ec Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@tremily.us>
Date: Sun, 2 Sep 2012 08:32:12 -0400
Subject: [PATCH] handler: add InvalidMessage.message_id convenience method.

---
 pygrader/handler/__init__.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/pygrader/handler/__init__.py b/pygrader/handler/__init__.py
index 1837721..3fb7b28 100644
--- a/pygrader/handler/__init__.py
+++ b/pygrader/handler/__init__.py
@@ -11,6 +11,19 @@ class InvalidMessage (ValueError):
         self.message = message
         self.error = error
 
+    def message_id(self):
+        """Return a short string identifying the invalid message.
+        """
+        if self.message is None:
+            return None
+        subject = self.message['Subject']
+        if subject is not None:
+            return repr(subject)
+        message_id = self.message['Message-ID']
+        if message_id is not None:
+            return message_id
+        return None
+
 
 class UnsignedMessage (InvalidMessage):
     def __init__(self, **kwargs):
-- 
2.26.2