Improve validation for FormAlchemy date field renderer

tailbone/forms/renderers/core.py

@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2015 Lance Edgar
+#  Copyright © 2010-2016 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -24,16 +24,16 @@
 Core Field Renderers
 """
 
-from __future__ import unicode_literals
+from __future__ import unicode_literals, absolute_import
 
 import datetime
 
-import formalchemy
+import formalchemy as fa
 from formalchemy.fields import AbstractField
 from pyramid.renderers import render
 
 
-class CustomFieldRenderer(formalchemy.FieldRenderer):
+class CustomFieldRenderer(fa.FieldRenderer):
     """
     Base class for renderers which accept customization args, and "fake out"
     FormAlchemy by pretending to still be a renderer factory when in fact it's
@@ -59,7 +59,7 @@ class CustomFieldRenderer(formalchemy.FieldRenderer):
         return self.request.rattail_config
 
 
-class DateFieldRenderer(CustomFieldRenderer, formalchemy.DateFieldRenderer):
+class DateFieldRenderer(CustomFieldRenderer, fa.DateFieldRenderer):
     """
     Date field renderer which uses jQuery UI datepicker widget when rendering
     in edit mode.
@@ -79,7 +79,12 @@ class DateFieldRenderer(CustomFieldRenderer, formalchemy.DateFieldRenderer):
         value = self._serialized_value()
         if not value:
             return None
+        try:
             return datetime.datetime.strptime(value, '%Y-%m-%d')
+        except ValueError:
+            raise fa.ValidationError("Date value must be in YYYY-MM-DD format")
+        except Exception as error:
+            raise fa.ValidationError(unicode(error))
 
     def _serialized_value(self):
         return self.params.getone(self.name)