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Re: Facebook Linked Data

From: Kingsley Idehen <kidehen@openlinksw.com>
Date: Mon, 26 Sep 2011 11:37:46 -0400
Message-ID: <4E809C4A.4010803@openlinksw.com>
To: public-lod@w3.org
On 9/26/11 11:24 AM, Alvaro Graves wrote:
> No, because you are requesting a document
> ----
> Alvaro Graves
>
> No, because you are requesting a _document_ (in my case 
> http://graph.facebook.com/672247057) which describes a person 
> (http://graph.facebook.com/672247057#). When I request a document (and 
> it exists) the expected HTTP code should be 200.

Object ID -- http://graph.facebook.com/672247057#
Object Representation Address (how you actually get at the data): 
http://graph.facebook.com/672247057 .

Courtesy of Linked Data indirection you have two routes to the data. 
Thus, when you use the Object ID (Name) a more powerful abstraction 
kicks in, one that's in line with fundamentals of Object Identity i.e., 
an Object has Identity distinct from its Representation.

Kingsley
>
>
> On Mon, Sep 26, 2011 at 8:16 AM, Sebastian Schaffert 
> <sebastian.schaffert@salzburgresearch.at 
> <mailto:sebastian.schaffert@salzburgresearch.at>> wrote:
>
>     But then I would say the server should at least reply with a 30x
>     redirect ;-)
>
>     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
>     --
>     | 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
>
>


-- 

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 15:38:24 UTC

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