compatiblity with cool URIs (Re: [xdi] Minutes: XDI TC TeleconThursday 1-2PM PT 2010-06-10)

["Giovanni Bartolomeo" <giovanni.bartolomeo@uniroma2.it>]

I went through an AP taken last week..

Def. Quota "Drummond Reed" <drummond.reed@xdi.org>:

> 2) PDX EXAMPLE DOCUMENT
>
>    http://wiki.oasis-open.org/xdi/PdxExample
>
> The $is topic is currently being discussed on the list. The only other topic
> we had time for on today's call was the relationship between PDX and FOAF
>
> Giovanni asked how we will proceed with this type of mapping, i.e., creating
> an XDI dictionary where the majority of the job is mapping to existing RDF
> vocabulary. Drummond gave the following example of what such a vocabulary
> mapping would look like:
>
>     $(http://some.example.com/rdf-vocabulary-uri)
>
> Giovanni wondered why the leading global context symbol was necessary. Bill
> and Drummond replied that it makes the cross-reference into an absolute XRI.
>
> http://xmlns.com/foaf/spec/#term_familyName <-- FOAF family name definition
>
> (http://xmlns.com/foaf/spec/#term_familyName) <-- relative XRI
>
> +(http://xmlns.com/foaf/spec/#term_familyName) <-- absolute XRI
>
>  Bill's POV was that this is needed because
>
> (http://xmlns.com/foaf/spec/#term_familyName)
>
> cannot be differentiated in type from
>
> (+foo)
>
> However
>
> +(http://xmlns.com/foaf/spec/#term_familyName)
>
> is differentiatable from
>
> (+foo)
>
> and we can say any XRI of the form +(xxx) maps to the URI space
>
> Giovanni:
> Not all URI associated to ontology concepts are "+" (i.e. things), they
> could be organizations "@", individuals "=", and "meta concepts" "$" as
> well.
>
> Bill:
> +(http://example.org) is not the XRI for example.org, that'd be @example. In
> other words, +(http://example.org) points to *the resource* identified by
> http://example.org
>
> Giovanni:
> What about...
>
> @example/$is/(http://example.org)
>
> Are they not  just synonyms?
>
> Bill:
> Wouldn't it be
>
> @example/$owns/(http://example.org)
>
> Not $is?
>
> Giovanni:
> Interesting, there is a discussion in the RDF/OWL community on how to
> differentiate URI pointing to resources from concepts.. it is the discussion
> about cool uri, etc... maybe you know as well. I've to check again their
> pages and come back to this topic then."
>
> Bill:
> Yes, that's what I am drawing from. If I have a URI for
> http://drummond.reed.name does that identify Drummond or does it identify a
> resource containing data about drummond. "Cool URIs Don't Change" was the
> paper that partially sparked it I think, TBLs paper.
> TBL = Tim Berners-Lee
>
> Giovanni
> right
>
> # ACTION: take a look at that paper and check their solution, then compare
> with ours
>

I've taken a look at the paper I quoted during last phc, actually it  
was a different paper than the one by TBL:

http://www.dfki.uni-kl.de/~sauermann/2006/11/cooluris/

The suggested way to proceed by this paper is as follow.

URI for giovanni, bill, drummond, etc. (resources without a  
representation, as they are people not information resources) :  
http://example.org/about#giovanni, http://example.org/about#bill,  
http://example.org/about#drummond

URI for giovanni's, bill's and drummond's representation (i.e. a human  
readable html document or machine readable rdf document - so called  
"information resources" - containing their description):  
http://example.org/people
NOTE: just one (cumulative) for all three people

Coming back to our example:

@example/$is/(http://example.org/#example)
(http://example.org/#example)/$is/@example

and the original example

+familyName/$is/(http://xmlns.com/foaf/spec/#term_familyName)
(http://xmlns.com/foaf/spec/#term_familyName)/$is/+familyName

regarding adding the gcs "+" or "@", apart from the syntactic need  
(relative vs absolute), why cannot we consider  
http://example.org/#example as it is accepted in the web, i.e. a  
"cool" URI identifying example.org? This way, cool URIs would be 100%  
compatible with XDIs (one to one mapping), facilitating the acceptance  
of our work in other standard development organizations.

Talking with you later... Kind Regards,
Giovanni



----------------------------------------------------------------
Invito da parte dell'Ateneo:
Il tuo futuro e quello della Ricerca Scientifica hanno bisogno del
tuo aiuto. Dona il  5 x mille all'Universita' di Roma Tor Vergata
codice fiscale: 80213750583 http://5x1000.uniroma2.it