- From: Pat Hayes <phayes@ihmc.us>
- Date: Fri, 23 Aug 2013 21:19:47 -0700
- To: Ivan Herman <ivan@w3.org>
- Cc: W3C RDF WG <public-rdf-wg@w3.org>, Felix Sasaki <fsasaki@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