Update Metadata on image files should trigger a "touch" operation on digilib prescale [was #35645]
If metadata for an image changes the image in the presacle cache is not touched. This however causes digilib to not use the prescaled image anymore, as the date of the image is older than the last-modified date in the metadata. So images are loaded from tgcrud than, causing slowdowns in image delivery.
So in this case loading the image via an exist-portal takes 8sec on first load, but 2 seconds after the image is in nginx cache.
After doing a touch on the image and cleaning caches the image loads in 2sec directly from prescale cache.
So on update-metadata the digilib-presacle messagebean should update the date of the image in prescale cache