Re: Facebook Linked Data

Hi Sebastian.

Please see in-line comments below.

On Sep 26, 2011, at 7:46 AM, Sebastian Schaffert 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,2011:/> .
> @prefix og: <http://ogp.me/ns#> .
> @prefix fb: <http://ogp.me/ns/fb#> .
> @prefix : <http://graph.facebook.com/schema/~/> .
> @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>
>

That's strange.  The data I get back is:

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-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,2011:/> .
@prefix og: <http://ogp.me/ns#> .
@prefix fb: <http://ogp.me/ns/fb#> .
@prefix : <http://graph.facebook.com/schema/~/> .
@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> ;
	user:username "sebastian.schaffert" ;
	user:gender "male" ;
	user:locale "de_DE" .

>
>
> 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.
>

I'm not sure I see the issue here.  http://graph.facebook.com/sebastian.schaffert 
  is a URL at which data about the person represented by http://graph.facebook.com/561666514# 
  can be found.  Following httpRange-14, since http://graph.facebook.com//561666514# 
  is a hash URI, the fragment (in this case, just '#') should be  
stripped away and http://graph.facebook.com/561666514 should return  
data about the person represented by http://graph.facebook.com/561666514# 
  with 200 OK.

> 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.
>

There is no explicit base here, and that is acceptable in Turtle.  The  
data is not (and should not be) customized to the limitations of a  
particular tool.

> Lastly, the returned data does not contain the trailing "." required  
> by turtle (see http://www.w3.org/TeamSubmission/turtle/#sec-grammar-grammar) 
> .
>

The data I received (above) does include the trailing ".", after three  
more triples.

> 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,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/
>>
>>
>>
>>
>>
>
> Sebastian
> -- 
> | Dr. Sebastian Schaffert          sebastian.schaffert@salzburgresearch.at
> | Salzburg Research Forschungsgesellschaft  http://www.salzburgresearch.at
> | Head of Knowledge and Media Technologies Group          +43 662  
> 2288 423
> | Jakob-Haringer Strasse 5/II
> | A-5020 Salzburg
>
>

Jesse Weaver
Ph.D. Student, Patroon Fellow
Tetherless World Constellation
Rensselaer Polytechnic Institute
http://www.cs.rpi.edu/~weavej3/index.xhtml

Received on Monday, 26 September 2011 17:57:06 UTC