Re: Is 303 really necessary? (dealing with ambiguity)

Hi David,

David Booth wrote:
> There are millions of people that use URIs to identify billions of web
> pages, and the vast majority have never heard of RDF.

Most of these millions haven't heard of, nor care about, the HTML
contained in the web page either. Thus, saying that millions of people
use the URI to denote the underlying HTML document seems like a stretch
of imagination.

> If your toucan
> URI returns a 200 response just like billions of other URIs then it
> *does* identify a web page, even if you are also using that URI in some
> RDF document to identify a toucan -- a document that would just be
> gobbledygook to most of the world.

Reading W3 mailing lists have made me wary of words like "identify". You
can get a home page by doing a HTTP GET on the URI, but the relationship
to the original URI is not well defined. Why can't we just leave it like
that. Use RDF for describing resources in detail.

> And others may well make statements
> about that web page.  For example, someone crawling the web may make a
> statement saying that <http://iandavis.com/2010/303/toucan> returned
> 1027 bytes in response to a GET request.  They may not say it in RDF --
> they might say it in XML or any other language.

As long as they they are aware that they are talking about a specific
representation of this resource I can't see any problem with this. If
they think they are stating something about the resource itself, well
they would be wrong even if the current URI was an "information
resource". They apparently need to learn more about web technology -
representations, caching, con-neg, &c.

> (Indeed, they may know
> nothing about RDF.)  But they still use
> http://iandavis.com/2010/303/toucan to identify the web page, and no
> amount of RDF can change that fact.  Furthermore, their statements may
> eventually be translated to RDF -- perhaps by someone else -- and merged
> with other assertions that use <http://iandavis.com/2010/303/toucan> to
> refer to the toucan.  

OK, they might. Do you have any examples of problems with Ian's approach
that are likely to happen at the moment?

> So I don't think it is reasonable or realistic to think that we can
> *avoid* creating an ambiguity by returning additional RDF statements
> with the 200 response.  Rather, the heuristic that you propose is a way
> for applications to *deal* with that ambiguity by tracking the
> provenance of the information: if one set of assertions was derived from
> an HTTP 200 response code, and another set of assertions was derived
> from an RDF document that you trust, then ignore the assertions that
> were derived from the HTTP 200 response code.

By not drawing ill-founded conclusions about the nature of the resource
through the response code, ambiguity could have been avoided in the
first place.

Tore rEiksson

_______________________________________________________________
Tore Eriksson [tore.eriksson at po.rd.taisho.co.jp]

Received on Monday, 8 November 2010 07:18:58 UTC