Re-work FalafelDateTime logic a bit

need to be more "standard" in how (de)serialize works etc.

also be sure to show error messages if present, not just field helptext

tailbone/forms/core.py

@@ -886,9 +886,6 @@ class Form(object):
             if field.cstruct is colander.null:
                 return '[]'
 
-        if isinstance(field.schema.typ, types.FalafelDateTime):
-            return field.cstruct
-
         try:
             return self.jsonify_value(field.cstruct)
         except Exception as error:
@@ -980,32 +977,31 @@ class Form(object):
             if field and isinstance(field.schema.typ, deform.FileData):
                 attrs['class_'] = 'file'
 
-            # show helptext if present
-            # TODO: older logic did this only if field was *not*
-            # readonly, perhaps should add that back..
-            if self.has_helptext(fieldname):
-                msgkey = 'message'
-                if self.dynamic_helptext.get(fieldname):
-                    msgkey = ':message'
-                attrs[msgkey] = self.render_helptext(fieldname)
+            # next we will build array of messages to display..some
+            # fields always show a "helptext" msg, and some may have
+            # validation errors..
+            field_type = None
+            messages = []
 
             # show errors if present
             error_messages = self.get_error_messages(field) if field else None
             if error_messages:
+                field_type = 'is-danger'
+                messages.extend(error_messages)
 
-                # TODO: this surely can't be what we ought to do
-                # here..?  seems like we must pass JS but not JSON,
-                # sort of, so we custom-write the JS code to ensure
-                # single instead of double quotes delimit strings
-                # within the code.
-                message = '[{}]'.format(', '.join([
+            # show helptext if present
+            # TODO: older logic did this only if field was *not*
+            # readonly, perhaps should add that back..
+            if self.has_helptext(fieldname):
+                messages.append(self.render_helptext(fieldname))
+
+            # ..okay now we can declare the field messages and type
+            if field_type:
+                attrs['type'] = field_type
+            if messages:
+                attrs[':message'] = '[{}]'.format(', '.join([
                     "'{}'".format(msg.replace("'", r"\'"))
-                    for msg in error_messages]))
-
-                attrs.update({
-                    'type': 'is-danger',
-                    ':message': message,
-                })
+                    for msg in messages]))
 
             # merge anything caller provided
             attrs.update(bfield_attrs)

tailbone/forms/types.py

@@ -102,17 +102,28 @@ class FalafelDateTime(colander.DateTime):
         app = self.request.rattail_config.get_app()
         dt = app.localtime(appstruct, from_utc=True)
 
-        return json.dumps({
+        return {
             'date': str(dt.date()),
             'time': str(dt.time()),
-        })
+        }
 
     def deserialize(self, node, cstruct):
         if not cstruct:
             return colander.null
 
+        try:
+            date = datetime.datetime.strptime(cstruct['date'], '%Y-%m-%d').date()
+        except:
+            node.raise_invalid("Missing or invalid date")
+
+        try:
+            time = datetime.datetime.strptime(cstruct['time'], '%H:%M:%S').time()
+        except:
+            node.raise_invalid("Missing or invalid time")
+
+        result = datetime.datetime.combine(date, time)
+
         app = self.request.rattail_config.get_app()
-        result = datetime.datetime.strptime(cstruct, '%Y-%m-%dT%H:%M:%S')
         result = app.localtime(result)
         result = app.make_utc(result)
         return result

tailbone/forms/widgets.py

@@ -242,6 +242,17 @@ class FalafelDateTimeWidget(dfwidget.DateTimeInputWidget):
     """
     template = 'datetime_falafel'
 
+    def serialize(self, field, cstruct, **kw):
+        readonly = kw.get('readonly', self.readonly)
+        values = self.get_template_values(field, cstruct, kw)
+        template = self.readonly_template if readonly else self.template
+        return field.renderer(template, **values)
+
+    def deserialize(self, field, pstruct):
+        if pstruct  == '':
+            return colander.null
+        return pstruct
+
 
 class FalafelTimeWidget(dfwidget.TimeInputWidget):
     """