def update_thumbnails_on_modify(obj, event):
for attr in event.descriptions:
if attr.interface is None: continue
fields = [x for x, y in schema.getFields(attr.interface).items() if
IImageField.providedBy(y)]
for fname in attr.attributes:
if fname in fields:
update_thumbs(obj, fname)
def update_thumbnails_on_create(obj, event):
for iface in component.providedBy(obj).flattened():
for fname, field in schema.getFields(iface).items():
if IImageField.providedBy(field):
update_thumbs(obj, fname)
