Some DC requirements

Below are some requirements from DC that may differ somewhat from the 
stories already in the wiki. I do see some overlap, but the stories 
themselves are different. (If someone could add these to the wiki, I'd 
be grateful. We're still having problems with wiki permissions for DC.)

I may have others but I'm posting this now because we are in the midst 
of a rain and wind storm that means that power is fragile, and it's just 
occurred to me that DSL modems really *should* have a battery backup, 
but do not.

******

Mandatory & Repeatable
by Karen Coyle
Folks in our community are used to cardinality being expressed as 
"mandatory or optional" and "repeatable or not-repeatable". We don't 
have any use cases for a more open-ended min/maxCardinality, so we wish 
to include these in our core requirements, with their "min/max" being 
defined in a layer that the requirements user does not see.

Checking the IRIs
by Karen Coyle
Europeana aggregates metadata about cultural heritage objects from 
hundreds of libraries, archives and museums. The incoming data needs to 
be thoroughly checked for accuracy. Among these checks are those on IRIs 
as values, which can vary depending on the property. Briefly, the checks are
1) the IRI must resolve, i.e. http status code = 2XX
2) the IRI value must return a media object of a given type (e.g. based 
on list of MIME types)
3) the IRI value must return an object which is of the rdf:type SKOS:Concept

Comparing values
by Karen Coyle
There are cases where the values in two or more triples have a specific 
relationship. The obvious one is "birthDate/deathDate" or 
"startDate/endDate". The validation model must allow these to be 
defined. One assumption is that the validation takes place within the 
context of a graph or node. Another is that the comparison is between 
literal values or datatypes, not IRIs. The question of whether this 
could be used more generally for ordering of lists is still being 
discussed, but it may be best to treat lists as a special case.

Defining allowed values
by Karen Coyle
Developers need to have these ways of defining the allowed values for 
each property
1) must be an IRI
2) must be an IRI matching this pattern (e.g. 
http://id.loc.gov/authorities/names/)
3) must be an IRI matching one of these patterns
4) must be a (any) literal
5) must be one of these literals ("red" "blue" "green")
6) must be a typed literal of this type (e.g. XML dataType)


-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet/+1-510-984-3600

Received on Thursday, 11 December 2014 15:24:42 UTC