Minutes of telecon 2012-08-21

Persons present: Omar, Markus, Gerard, Matthew, Patrick

Points discussed (not in temporal order):

Starting with a clean slate as far as the current working draft is concerned (while harvesting from the current text what's useful): None of the persons present object.

But: We'll have to first come up with a report that summarizes current usage of utypes (plus, when we have a better idea of where we want to go, the impact of any changes to current practice). Matthew volunteers to edit this report. Markus will help out.

Omar will be editor of the working draft, and we assume Mireille will also want to be part of the effort.

Omar will circulate a list of the use cases over the DM list; there's already something on this page (http://wiki.ivoa.net/twiki/bin/view/IVOA/UtypesTigerTeam), but it needs smoothing and elaboration. Documents will end up in volute.

We need to make explicit what are the prime use cases driving utypes. Not all of the ones on the wiki may be achieveable.

Attempts to define utypes: Are they "pointers into a data model instance", much like xpath points into a XML document? That much seems not very contentious. As far as this function is concerned, it is seen that inheritance and embedding are not very well dealt with now.

"I should be able to serialize and deserialize a data model instance in any way I want" using utypes (Matthew). But we obviously need to pose additional constraints on what the target formats need to be able to to (e.g., represent key-value pairs).

What formats do we actually care about? VOTable obviously, FITS probably (though some say people that want FITS won't care about data models), SAMP messages. JSON? No agreement. CSV doesn't have enough of a header to allow utype mapping, probably.

We've got about 8 weeks until the interop. What do we want to get done by then? We want the use cases in a form so TCG/plenary/whoever can decide which absolutely have to be covered, where we as Tiger Team provide comments/suggest priorities. We also must have the overview of where utypes are already used. Telecons every two weeks.