I'd like to extend the dexterity image object and add a "Last Accessed Date" field (plone 5.2) which would update anytime it is rendered. I know I can use XML schema to add fields, this is something a little more. Especially since this field needs to update when the object gets rendered. I extended objects back in the archetypes days but I am not sure the best way for dexterity. Most of the documentation only goes as deep as xml.
Why? My staff love uploading images, we have over 1500 now. Some are never used anymore and I want to purge the old ones. I can't tell what is used and what is not.
Due to retention policies of my work, we cannot keep access logs going back very long.
My thought is even if a bot hit a page which has the image, it is a valid image. I'm looking at images that have no association with content anymore. The site also hosts images for external sites too, so using a plone link check, won't work for those use cases.