Re: Linked Data and Semantic Web CoolURIs, 303 redirects and Page Rank.

[Kingsley Idehen]

On 7/23/14 5:15 PM, Michael Smethurst wrote:

On 23/07/2014 21:49, "Kingsley Idehen" <kide...@openlinksw.com> wrote:

On 7/23/14 3:40 PM, Michael Smethurst wrote:

Hi Kingsley

Very definitely starting to feel like deja vu...

On 23/07/2014 20:18, "Kingsley Idehen"<kide...@openlinksw.com>  wrote:

On 7/23/14 2:05 PM, Michael Smethurst wrote:

For internal usage it's all probably fine. But I still think it's a
pattern that shouldn't be generally encouraged.

Its a "horses for courses" matter:-)

If you choose to use hashless HTTP URIs in regards to entity

denotation,

you have to make the extra investment required (via 303 heuristics)

for

entity disambiguation [1].

My only point is: if you don't conflate "I can't send that" (303) with
"what flavour would you like" (conneg) you don't have to invest in more
servers

Note, there are changes to HTTP that also reduce some of the confusion
in this realm. For instance the use "Content-Location:" response

headers

to aid disambiguation [2].

We do use content location for the (information) resource /
representation
split but that's REST not 303 semantics

michael

There is only one kind of relation semantics in play here, and its the
semantics of denotation and connotation [1][2].

Tho derrida didn't have to pay for servers :-/

HTTP URIs denote things.

Which can't be served (303)

No, HTTP URIs simply denote things (entities). It has nothing to do with being served etc..

HTTP URLs denote documents comprised of connotation bearing content.

Which can be served in assorted representations (conneg (+ content
location))

No, HTTP URLs are a kind of HTTP URI that denote Web Documents. Put differently, HTTP URLs are for all intents an purposes a colloquialism for HTTP URIs that focuses on Web Documents, a particular entity type i.e., entities that are instances of the Classes denoted by the URIs: <http://xmlns.com/foaf/0.1/Document>, <http://purl.org/ontology/bibo/Document>, <http://purl.org/dc/terms/BibliographicResource> etc..

The very same analogy applies to WebIDs which are HTTP URIs that denote Agents i.e., entities that are instances of the Class denoted by the URI: <http://xmlns.com/foaf/0.1/Agent> .

Think the last time we had this conversation we broke the twitter scroll
bar and agreed to disagree. Or at worst misunderstand :-)

Long discussions aren't necessarily bad, they can also unravel insights that are sometimes overlooked :-) BTW -- one can also deconstruct this issue a different way, starting with HTTP URI/URLs that denote Documents. It goes something like this: 1. You have a RDF document (comprised of RDF/XML content) denoted by the HTTP URI/URL <http://www.bbc.co.uk/programmes/b006mw1h.rdf> 2. The document above describes an entity denoted by the HTTP URI <http://www.bbc.co.uk/programmes/b006mw1h#programme> .

We arrive at the same place (as illustrated by the Vapour links I shared).

My only issue with the BBC programmes URIs right now is that <http://www.bbc.co.uk/programmes/b006mw1h> doesn't make its association with <http://www.bbc.co.uk/programmes/b006mw1h#programme> discoverable to RDF user agents. That's where Microdata, RDFa, <link/>, "Link:" come into play i.e., they provide vehicles for exposing the missing relation (association, connection, relationship property/predicate etc..).

Also note:

curl -IH "Accept: application/rdf+xml" http://www.bbc.co.uk/programmes/b006mw1h

HTTP/1.1 200 OK
Server: Apache
Content-Type: text/html; charset=utf-8

curl -IH "Accept: application/rdf+xml" http://www.bbc.co.uk/programmes/b006mw1h.rdf

HTTP/1.1 200 OK
Server: Apache
Content-Type: application/rdf+xml






Kingsley

Which reinforces my point re. missing relation to aid RDF user agents. Simply tacking on ".rdf" to the end of URLs is way too brittle, when a relation (describes, describedby etc..) would do much better via RDFa, Microdata, <link/>, "Link:" etc..

michael

In regards, to the current BBC programmes URIs, if you incorporate RDFa,
<link/>, or "Link:" based relations, disambiguation without 303's or
content negotiation is possible. RDF user agents (for example) will be
able to make sense of the relations that that collective describe
documents about programmes and actual programmes.

Links:

[1] http://bit.ly/what-does-this-bbc-programmes-uri-denote -- Vapour
using RDF semantics discern what
<http://www.bbc.co.uk/programmes/b006mw1h> denotes and connotes

[2] http://bit.ly/what-does-this-bbc-programmes-doc-url-denote -- ditto
but targeting <http://www.bbc.co.uk/programmes/b006mw1h.rdf> .

--
Regards,

Kingsley Idehen 
Founder & CEO
OpenLink Software
Company Web: http://www.openlinksw.com
Personal Weblog 1: http://kidehen.blogspot.com
Personal Weblog 2: http://www.openlinksw.com/blog/~kidehen
Twitter Profile: https://twitter.com/kidehen
Google+ Profile: https://plus.google.com/+KingsleyIdehen/about
LinkedIn Profile: http://www.linkedin.com/in/kidehen
Personal WebID: http://kingsley.idehen.net/dataspace/person/kidehen#this

--
Regards,

Kingsley Idehen 
Founder & CEO
OpenLink Software
Company Web: http://www.openlinksw.com
Personal Weblog 1: http://kidehen.blogspot.com
Personal Weblog 2: http://www.openlinksw.com/blog/~kidehen
Twitter Profile: https://twitter.com/kidehen
Google+ Profile: https://plus.google.com/+KingsleyIdehen/about
LinkedIn Profile: http://www.linkedin.com/in/kidehen
Personal WebID: http://kingsley.idehen.net/dataspace/person/kidehen#this

smime.p7s
Description: S/MIME Cryptographic Signature