We are starting to roll out supports for * wildcard in unpacked.cern.ch and DUCC.
The code is already updated, so we are already ingesting some images using the * glob.
Examples
One example is the following from our friends in cms.
https://registry.hub.docker.com/cmssw/cms:rhel7-m*
This ingest all the tags that start with rhel7-m, so rhel7-m201911, rhel7-m202001 and rhel7-m202002 at the moment.
It is possible to use the wildcard to match also prefix and not just suffixes.
Of course is possible to use the wildcard also to match all the tags of an image.
https://registry.hub.docker.com/cmssw/cms:*
Internal details
Internally we use a regex engine, we convert * to .* and match the regex to all the tags of the images.
This means that we could also add support for the + wildcard.
Tests
From preliminary tests, it seems that everything is working fine, if somebody as an image to ingest it would be very interesting to try that as well.
The relevant PR is this one for the interested: https://github.com/cvmfs/cvmfs/pull/2490