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Re: Facebook Linked Data

From: Kingsley Idehen <kidehen@openlinksw.com>
Date: Mon, 26 Sep 2011 12:00:05 -0400
Message-ID: <4E80A185.7060308@openlinksw.com>
To: public-lod@w3.org, "semantic-web@w3.org" <semantic-web@w3.org>
On 9/26/11 11:37 AM, Alvaro Graves wrote:
>
>     We don't have to bring httpRange-14 and its timeless imbroglio
>     into every conversation re. Linked Data :-) 
>
>
> True :) the only important thing is to make clear that facebook URIs 
> for documents are different from URIs for people.

I prefer to speak about (with computer science continnum benefits in 
mind re. terminology):
1. Data Object Identifier (Name)
2. Data Object Representation via directed graphs
3. Data Object Access Address.

Indirection (via de-reference and address-of operators) re. data access 
by reference pattern is old, thus there's a large receptive audience at 
one's disposal when using said terminology.

It costs about 12+ years to fix the broken terminology pot :-)

Kingsley
> ----
> Alvaro Graves
>
>
> On Mon, Sep 26, 2011 at 8:34 AM, Kingsley Idehen 
> <kidehen@openlinksw.com <mailto:kidehen@openlinksw.com>> wrote:
>
>     On 9/26/11 11:16 AM, Sebastian Schaffert wrote:
>
>         But then I would say the server should at least reply with a
>         30x redirect ;-)
>
>
>     Not necessarily, they choosen to implement indirection internally,
>     rather than via HTTP response headers. Naturally, doing via HTTP
>     is more flexible and thereby desirable, but we have to accept that
>     "half bread is better than none" re. this matter i.e., any kind of
>     indirection is better than no indirection re. disambiguation of
>     Data Object ID and Address for accessing its Representation.
>
>     Kingsley
>
>         Greetings,
>
>         Sebastian
>
>         Am 26.09.2011 um 17:05 schrieb Alvaro Graves:
>
>             Hi Sebastian,
>
>             AFAIK it's not a bug, but a feature :). This is done to
>             comply with the httpRange-14 issue (i.e., you can't
>             retrieve a person through HTTP but you can retrieve a
>             document _about_ a person through HTTP). Since a person
>             and a document about a person are different entities, they
>             should have different URIs.
>
>             http://www.w3.org/2001/tag/issues.html#httpRange-14
>
>             ----
>             Alvaro Graves
>
>             On Mon, Sep 26, 2011 at 7:46 AM, Sebastian
>             Schaffert<sebastian.schaffert@salzburgresearch.at
>             <mailto:sebastian.schaffert@salzburgresearch.at>>  wrote:
>             Dear Jesse,
>
>             Thanks for the effort! I am just experimenting with this.
>             If I request my own Vanity URL
>
>             http://graph.facebook.com/sebastian.schaffert
>
>             The data I get back is:
>
>             @prefix rdf:<http://www.w3.org/1999/02/22-df-syntax-ns#>  .
>             @prefix rdfs:<http://www.w3.org/2000/01/rdf-schema#>  .
>             @prefix owl:<http://www.w3.org/2002/07/owl#>  .
>             @prefix xsd:<http://www.w3.org/2001/XMLSchema#>  .
>             @prefix api:<tag:graph.facebook.com
>             <http://graph.facebook.com>,2011:/>  .
>             @prefix og:<http://ogp.me/ns#>  .
>             @prefix fb:<http://ogp.me/ns/fb#>  .
>             @prefix :<http://graph.facebook.com/schema/~/
>             <http://graph.facebook.com/schema/%7E/>>  .
>             @prefix user:<http://graph.facebook.com/schema/user#>  .
>             </561666514#>
>                    user:id "561666514" ;
>                    user:name "Sebastian Schaffert" ;
>                    user:first_name "Sebastian" ;
>                    user:last_name "Schaffert" ;
>                    user:link<http://www.facebook.com/sebastian.schaffert>
>
>
>
>             Now the problem I see here is that the URI I requested is
>             not the same URI as used in the subject of the RDF
>             triples. Same holds btw if I request the data using the ID
>             including "#". Which is bad in our case because we filter
>             out triples that do not fulfill this condition to avoid
>             importing "invalid" data.
>
>             Also, the data should IMHO contain a @base statement
>             defining the base for the</561666514#>, because when
>             importing the data the original URI is sometimes no longer
>             available.
>
>             Lastly, the returned data does not contain the trailing
>             "." required by turtle (see
>             http://www.w3.org/TeamSubmission/turtle/#sec-grammar-grammar).
>
>             Are there plans to fix this? For me, the more readable
>             data would look like this:
>
>             @prefix rdf:<http://www.w3.org/1999/02/22-df-syntax-ns#>  .
>             @prefix rdfs:<http://www.w3.org/2000/01/rdf-schema#>  .
>             @prefix owl:<http://www.w3.org/2002/07/owl#>  .
>             @prefix xsd:<http://www.w3.org/2001/XMLSchema#>  .
>             @prefix api:<tag:graph.facebook.com
>             <http://graph.facebook.com>,2011:/>  .
>             @prefix og:<http://ogp.me/ns#>  .
>             @prefix fb:<http://ogp.me/ns/fb#>  .
>             @prefix user:<http://graph.facebook.com/schema/user#>  .
>             <http://graph.facebook.com/sebastian.schaffert>
>                    user:id "561666514" ;
>                    user:name "Sebastian Schaffert" ;
>                    user:first_name "Sebastian" ;
>                    user:last_name "Schaffert" ;
>                    user:link<http://www.facebook.com/sebastian.schaffert>
>
>
>
>             Am 23.09.2011 um 14:09 schrieb Jesse Weaver:
>
>                 APOLOGIES FOR CROSS-POSTING
>
>                 I would like to bring to subscribers' attention that
>                 Facebook now
>                 supports RDF with Linked Data URIs from its Graph API.
>                  The RDF is in
>                 Turtle syntax, and all of the HTTP(S) URIs in the RDF
>                 are dereferenceable
>                 in accordance with httpRange-14.  Please take some
>                 time to check it out.
>
>                 If you have a vanity URL (mine is jesserweaver), you
>                 can get RDF about you:
>
>                 curl -H 'Accept: text/turtle'
>                 http://graph.facebook.com/<vanity-url>
>                 curl -H 'Accept: text/turtle'
>                 http://graph.facebook.com/jesserweaver
>                 If you don't have a vanity URL but know your Facebook
>                 ID, you can use
>                 that instead (which is actually the fundamental method).
>
>                 curl -H 'Accept: text/turtle'
>                 http://graph.facebook.com/<facebook-id>
>                 curl -H 'Accept: text/turtle'
>                 http://graph.facebook.com/1340421292
>
>                      From there, try dereferencing URIs in the Turtle.
>                      Have fun!
>
>                 Jesse Weaver
>                 Ph.D. Student, Patroon Fellow
>                 Tetherless World Constellation
>                 Rensselaer Polytechnic Institute
>                 http://www.cs.rpi.edu/~weavej3/
>                 <http://www.cs.rpi.edu/%7Eweavej3/>
>
>
>
>
>
>             Sebastian
>             --
>             | Dr. Sebastian Schaffert
>             sebastian.schaffert@salzburgresearch.at
>             <mailto:sebastian.schaffert@salzburgresearch.at>
>             | Salzburg Research Forschungsgesellschaft
>             http://www.salzburgresearch.at
>             | Head of Knowledge and Media Technologies Group +43 662
>             2288 423 <tel:%2B43%20662%202288%20423>
>             | Jakob-Haringer Strasse 5/II
>             | A-5020 Salzburg
>
>
>
>         Sebastian
>
>
>
>     -- 
>
>     Regards,
>
>     Kingsley Idehen
>     President&  CEO
>     OpenLink Software
>     Web: http://www.openlinksw.com
>     Weblog: http://www.openlinksw.com/blog/~kidehen
>     <http://www.openlinksw.com/blog/%7Ekidehen>
>     Twitter/Identi.ca: kidehen
>
>
>
>
>
>
>


-- 

Regards,

Kingsley Idehen	
President&  CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen








Received on Monday, 26 September 2011 16:00:39 UTC

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