W3C home > Mailing lists > Public > public-rdf-wg@w3.org > August 2013

Re: Draft Review of the ITS 2.0 draft document

From: Pat Hayes <phayes@ihmc.us>
Date: Fri, 23 Aug 2013 21:19:47 -0700
Cc: W3C RDF WG <public-rdf-wg@w3.org>, Felix Sasaki <fsasaki@w3.org>
Message-Id: <8C1DEE00-23C2-46D2-AA5F-5578FD15260B@ihmc.us>
To: Ivan Herman <ivan@w3.org>
Ivan

While I sympathise with, and share, your discomfort, I don't see that this is an issue particularly for RDF to comment upon. RDF, as you note, treats IRIs as opaque, so this entire discussion seems irrelevant to RDF-WG. Maybe some other WG, or the TAG, should be asked to take up this issue with ITS WG ?

Pat


On Aug 23, 2013, at 5:57 AM, Ivan Herman wrote:

> As recorded as an action (wait, it was not recorded on the call because tracker got confused by several ivan-s:-) I reviewed the ITS 2.0 document, as requested by the ITS WG via Felix Sasaki[1]. The section that is relevant for this Working Group is the mapping to an external ontology, called NIF[2]. Actually, the details of that ontology are also not relevant for this Working Group; the issue is to map the attributes set on the textual content of an HTML (or XML) document into RDF.
> 
> To take the example of the document:
> 
> <html><body><h2 translate="yes">Welcome to <span 
>  its-ta-ident-ref="http://dbpedia.org/resource/Dublin" its-within-text="yes"
>  translate="no">Dublin</span> in 
>  <b translate="no" its-within-text="yes">Ireland</b>!</h2></body></html>
> 
> the goal is to produce a set of RDF statements of the form:
> 
> <URI_TO_IDENTIFY_A_TEXT_PORTION>
>   nif:property1 value1;
>   nif:property2 value2;
>   nif:prop <URI_TO_IDENTIFY_A_TEXT_POSITION>
>   ...
> 
> The really interesting question is how to define the two URI-s <URI_TO_IDENTIFY_A_TEXT_PORTION> and <URI_TO_IDENTIFY_A_TEXT_POSITION>, where, say, the first should somehow refer to "Welcome to Dublin Ireland!" and the other should tell the world that this text is within the <h2> element of the file.
> 
> The current mapping uses the following two URI-s
> 
> <http://example.com/exampledoc.html#char=0,29>
> <http://example.com/exampledoc.html#xpath(/html/body[1]/h2[1])>
> 
> although it is quite obvious what these are for, I sense some sort of a problem with these. We may end in a rathole, but...
> 
> - We refer to IRI-s in our concept document: RFC3987
> - IRI-s map to URI-s: RFC3987
> - What RFC3987 says about fragments is:
> 
> "The fragment's format and resolution is therefore dependent on the media type [RFC2046] of a potentially retrieved representation, even though such a retrieval is only performed if the URI is dereferenced.  If no such representation exists, then the semantics of the fragment are considered unknown and are effectively unconstrained."
> 
> The way I translate is that if I want to have a proper URI, where I expect the media type to be BLA, then the fragment ID should somehow be defined for BLA. Although RDF regards IRI-s as opaque, I would still feel uneasy to do otherwise.
> 
> Looking at the URI-s above
> 
> - The 'char' fragment is defined by rfc 5147, but is defined for text/plain only. ITS talks about XML and HTML, ie, talks about resources whose media types are definitely _not_ text/plain
> - The xpath fragment id is fine for XML. But it is not defined for text/html and, knowing how XML is frown upon by the HTML WG, I do not expect that to ever change.
> 
> In view of this, I do not feel comfortable with the choice of the mapping. The URI-s are not dereferenceable, neither are they correct...
> 
> That being said, I may be too picky and we could let this go, also considering the fact that this section is _not_ normative in ITS.
> 
> I had some discussion with Felix and also with Sebastian Hellmann, who is the author of NIF; one proposal I had was to use a URI of the form
> 
> http://www.w3.org/its?resource=http://example.com/exampldoc.html&char=0,29 
> 
> which, if some simple service is provided, can provide some simple information back, and is ok as a URI. I think that would be acceptable to them. But again, this WG may decide that I am just way too pedantic...
> 
> Ivan
> 
> P.S. It is of course possible to radically change the mapping with some blank nodes in the middle to avoid the issue...
> 
> [1] http://lists.w3.org/Archives/Public/public-rdf-wg/2013Aug/0000.html
> [2] http://www.w3.org/TR/2013/WD-its20-20130820/#conversion-to-nif
> 
> ----
> Ivan Herman, W3C 
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> FOAF: http://www.ivan-herman.net/foaf.rdf
> 
> 
> 
> 
> 
> 
> 

------------------------------------------------------------
IHMC                                     (850)434 8903 home
40 South Alcaniz St.            (850)202 4416   office
Pensacola                            (850)202 4440   fax
FL 32502                              (850)291 0667   mobile (preferred)
phayes@ihmc.us       http://www.ihmc.us/users/phayes
Received on Saturday, 24 August 2013 04:20:13 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:04:31 UTC