1 files changed, 15 insertions, 0 deletions

diff --git a/src/mailman/rest/validator.py b/src/mailman/rest/validator.py
index d8297e519..cf32ca838 100644
--- a/src/mailman/rest/validator.py
+++ b/src/mailman/rest/validator.py
@@ -23,9 +23,13 @@ __metaclass__ = type
 __all__ = [
     'Validator',
     'enum_validator',
+    'subscriber_validator',
     ]
 
 
+from uuid import UUID
+
+
 COMMASPACE = ', '
 
 
@@ -42,6 +46,17 @@ class enum_validator:
         return self._enum_class[enum_value]
 
 
+
+    
+def subscriber_validator(subscriber):
+    """Convert an email-or-int to an email-or-UUID."""
+    try:
+        return UUID(int=int(subscriber))
+    except ValueError:
+        return subscriber
+
+
+
 class Validator:
     """A validator of parameter input."""