Re: URIs within URIs

Hi Ruben,
Cool posting.

Can you tell me id there is a pattern for the uri= style stuff, where you want everything the service wants to say about the URI, in any position?
For a simple site this might look like the SCBD for the URI?
And I guess that raises the question of bnodes as well.
I have looked a bit at the paper and the spec, but couldn’t find it and I’m feeling lazy - sorry :-)

I suppose I am looking at LDF from the point of view of it is a way of specifying the invoking URI pattern, and what my services would look like if they were using such patterns to be invoked - although maybe that is misuse?

Best
Hugh

On 22 Aug 2014, at 17:19, Ruben Verborgh <ruben.verborgh@ugent.be> wrote:

> Hi Luca,
> 
>> I'm wondering whether there has been any research regarding the idea
>> of having URIs contain an actual URI, that would then resolve
>> information about what the linked dataset states about the input URI.
>> 
>> Example:
>> 
>> http://foo.com/alice -> returns data about what foo.com has regarding alice
>> 
>> http://bar.com/endpoint?uri=http%3A%2F%2Ffoo.com%2Falice -> doesn't
>> just resolve the alice URI above, but returns what bar.com wants to
>> say about the alice URI
> 
> This specific use case has been one of the motivations behind Triple Pattern Fragments [1][2].
> Section 4.3 of our publication on the Linked Data on the Web workshop [2] specifically tackles this issue.
> 
> The problem with dereferencing is that the URI of a concept
> only leads to the information about this concept by the particular source
> that has created this specific URI—even though there might be others.
> For instance, even if http://example.org/#company was the official URI of
> the company EXAMPLE, it is unlikely the source of the most objective information
> about this company. But how can we find that information then?
> 
> And the problem gets worse with URIs like http://xmlns.com/foaf/0.1/Person.
> This URI gives you exactly 0 persons, as strange as this might seem to an outsider.
> 
> 
> With Triple Pattern Fragments, you can say:
> “give me all information this particular dataset has about concept X.”
> For instance, given the resource http://dbpedia.org/resource/Barack_Obama,
> here is data for this person *in a specific dataset*:
> http://data.linkeddatafragments.org/dbpedia?subject=http%3A%2F%2Fdbpedia.org%2Fresource%2FBarack_Obama
> 
> Here is data about http://xmlns.com/foaf/0.1/Person in that same dataset:
> http://data.linkeddatafragments.org/dbpedia?object=http%3A%2F%2Fxmlns.com%2Ffoaf%2F0.1%2FPerson
> 
> Note how these resources are *not* created by hacking URI patterns manually;
> instead, you can find them through a hypermedia form:
>    - http://data.linkeddatafragments.org/dbpedia
> This form woks for both HTML and RDF clients, thanks to the Hydra Core Vocabulary.
> In other words, this interface is a hypermedia-driven REST interface through HTTP.
> 
> 
> This gets us to a deeper difference between (current) Linked Data and the rest of the Web:
> Linked Data uses only links as hypermedia controls,
> whereas the remainder of the Web uses links *and forms*.
> Forms are a much more powerful mechanism to discover information.
> 
> So part of what we want to achieve with Triple Pattern Fragments
> is to broaden the usage of Linked Data from links to more expressive hypermedia.
> This truly allows “anybody to say anything about anything”—
> and to discover that information, too!
> 
>> I know SPARQL endpoints already have this functionality, but was
>> wondering whether any formal research was done towards this direction
>> rather than a full-blown SPARQL endpoint.
>> 
> 
>> The reason I'm looking for this sort of thing is because I simply need
>> to ask certain third-party datasets whether they have data about a URI
>> (inbound links).
> 
> Consider using a Triple Pattern Fragments server [3].
> Their handy and very cheap to host in comparison to SPARQL servers!
> 
> Best,
> 
> Ruben
> 
> [1] http://www.hydra-cg.com/spec/latest/triple-pattern-fragments/
> [2] http://ceur-ws.org/Vol-1184/ldow2014_paper_04.pdf
> [3] https://github.com/LinkedDataFragments/Server.js

-- 
Hugh Glaser
   20 Portchester Rise
   Eastleigh
   SO50 4QS
Mobile: +44 75 9533 4155, Home: +44 23 8061 5652

Received on Friday, 22 August 2014 17:21:00 UTC