def __call__(self, request):
if not IQuickChangenoteLayer.providedBy(request):
return
# Archetypes will call us three times, and that complicates things.
# Either the change note is there or it isn't. If its there the first
# time, its not about to disappear during the processing of the
# request. Therefore annotate the return value on the request.
cache_key = "validate_changenote_result"
_marker = object()
cache = IAnnotations(request)
data = cache.get(cache_key, _marker)
if data is not _marker:
return data
context = aq_inner(self.context)
if IQuickChangenoteLayer.providedBy(request) and \
changenoteRequired(context) and isVersionable(context) and \
supportsAutoVersion(context):
value = request.form.get(self.field_name,
request.get(self.field_name, ''))
if len(value) == 0:
errors = {self.field_name: _(
u'A change note must be provided')}
cache[cache_key] = errors
return errors
cache[cache_key] = None
return None
def required(self):
""" returns whether a change note is required on each save. """
return changenoteRequired(self.context)
