W3C home > Mailing lists > Public > public-lod@w3.org > November 2010

Facebook OpenGraphProtocol (was Re: Is 303 really necessary?)

From: Tim Berners-Lee <timbl@w3.org>
Date: Sun, 28 Nov 2010 10:08:19 -0500
Cc: Ian Davis <lists@iandavis.com>, William Waites <ww@styx.org>, Richard Light <richard@light.demon.co.uk>, Linked Data community <public-lod@w3.org>
Message-Id: <5C5765FE-C83C-45D9-A18F-E590501534F2@w3.org>
To: Giovanni Tummarello <giovanni.tummarello@deri.org>
Giovani,

When you say "the rest of the web", this issue is specifically one 
with Facebook Open Graph Protocol, which i a new development.

When you look at the triples
http://inspector.sindice.com/inspect?url=http://www.rottentomatoes.com/celebrity/antonio_banderas/#TRIPLES
(Nice view)
the you get many triples about the page,  like
<http://www.rottentomatoes.com/celebrity/antonio_banderas/> <http://www.w3.org/1999/xhtml/vocab#stylesheet> <http://images.rottentomatoescdn.com/files/inc_beta/css/2.0.0/header_v2.css?v=glo20101121> .
This clearly is about the document.
(I don' think it is very interesting as data, so defining it to be part of the
RDF triples of a document without the alternative of a more constrained set
is another issue.) 

The ones which are from the OGP are like
<http://www.rottentomatoes.com/celebrity/antonio_banderas/> <http://opengraphprotocol.org/schema/type> "actor" .

There are of course various ways of mapping this to what you and
would have probably coded up. 

1) One way if to just recognize that the
predicates in the OGP are relations to the page.


{ ?page fb:image ?x. ?page foaf:primarySubject ?y } => { ?y foaf:image ?x }.

and that is not the end of the world.

But it is consistent.


2) There is another way, and that is to make a new RDFA syntax really easy to
add triples specifically about the subject of the page.




Note that the 303/208 issue is separate to this. This OGP problem remains if you use 208 or 200)

Tim



On 2010-11 -28, at 08:52, Giovanni Tummarello wrote:

>> - the rest of the web continue to use 200
>> 
>> Tim
> 
> yes but the rest of the web will use 200 also to show what we would
> consider 208, e.g.
> 
> http://www.rottentomatoes.com/celebrity/antonio_banderas/
> 
> see the trilples
> http://inspector.sindice.com/inspect?url=http://www.rottentomatoes.com/celebrity/antonio_banderas/#TRIPLES
> 
> http://www.rottentomatoes.com/celebrity/antonio_banderas/
> 
> is clearly a web page but its also an actor, it is pointed by their
> graph in other pages as such and the same page contains the opengraph
> triple  "type" "actor"
> 
> We should not get ourself in the position to have to try to evangelize
> all to change something for reasons that are really not apparent to
> your normal web world. I think the solution we should be seeking
> consider RDFa publishing via normal 200 code as the example above
> absolutely ok
> 
> an agent would then be able to distinguish which properties apply to
> the "page" and which to the "actor" looking at the.. properties
> themselves i guess?  sad but possibly unavoidable?

No, absolutely horrible.  
A total disaster IMHO. 
Think how many properties of a library catalog card and a book both have.
What do you do with these triples

<> a Book.
<> a CardCatalog.
<> creator  people:AGEdelan3.
<> creator people:HSWhite23.
<> length 1052.
<> length  105675.

That way lies madness.


> 
> Giovanni
> 
Received on Sunday, 28 November 2010 15:08:26 UTC

This archive was generated by hypermail 2.3.1 : Sunday, 31 March 2013 14:24:30 UTC