- From: Paul Groth <p.t.groth@vu.nl>
- Date: Wed, 2 Jan 2013 16:04:35 +0100
- To: Graham Klyne <Graham.Klyne@zoo.ox.ac.uk>
- Cc: Timothy Lebo <lebot@rpi.edu>, "Cresswell, Stephen" <stephen.cresswell@tso.co.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
- Message-ID: <CAJCyKRos_JVg6H6w+YJBZQyOMfk7457oJOKyS7oUbyDNC006Bw@mail.gmail.com>
This seems like the only option, in particular, if we ensure that that the template that needs to be returned is ligh-weight.... regards Paul On Wed, Jan 2, 2013 at 3:49 PM, Graham Klyne <Graham.Klyne@zoo.ox.ac.uk>wrote: > Tim, > Paul, > > Following an extended discussion with Erik Wilde, I'm now persuaded that > an new > link relation is not the best way to go for SPARQL endpoints. > > I the absence of a clear alternative proposal, I propose to stick with RDF > (in > any of its syntaxes) for the service description. > > I do think we want an easy way to distinguish different service > implementations > in an RDF service description, and my preference for this would be the > rdf:type > of the described service resource. > > Thus, if we have a provenance service that supports both the templated and > SPARQL interfaces, I would anticipate a service description along these > lines: > > [[ > <#template> a prov:ProvenanceService ; > prov:provenanceUriTemplate "http://www.example.net/prov?target={+uri} > " > . > > <#sparql> a sd:Service ; > # (description per http://www.w3.org/TR/sparql11-service-description/ > ) > sd:endpoint <http://www.example.net/sparql/> ; > sd:supportedLanguage sd:SPARQL11Query ; > sd:resultFormat <http://www.w3.org/ns/formats/RDF_XML> , > <http://www.w3.org/ns/formats/Turtle> , > <http://www.w3.org/ns/formats/SPARQL_Results_XML> , > <http://www.w3.org/ns/formats/SPARQL_Results_JSON> , > <http://www.w3.org/ns/formats/SPARQL_Results_CSV> , > <http://www.w3.org/ns/formats/SPARQL_Results_TSV> > . > ]] > > I think it's easy to see how this can generalize to accommodate alternative > services if such are introduced later. > > In practice, I anticipate that different service URIs (indicated by > multiple > provenance service link headers) would each implement a single access > mechanism, > so the multiple options within a single service description as shown above > are > not a requirement. > > Tim: you indicated previously that prov:ProvenanceService should apply to > *all* > forms of provenance service. I haven't proposed that above, but it would > be > possible to have this as a generic class for all provenance services, with > the > above example then becoming, say: > > [[ > <#template> a prov:TemplatedService, prov:ProvenanceService ; > prov:provenanceUriTemplate "http://www.example.net/prov?target={+uri} > " > . > > <#sparql> a sd:Service, prov:ProvenanceService ; > # (description per http://www.w3.org/TR/sparql11-service-description/ > ) > sd:endpoint <http://www.example.net/sparql/> ; > sd:supportedLanguage sd:SPARQL11Query ; > sd:resultFormat <http://www.w3.org/ns/formats/RDF_XML> , > <http://www.w3.org/ns/formats/Turtle> , > <http://www.w3.org/ns/formats/SPARQL_Results_XML> , > <http://www.w3.org/ns/formats/SPARQL_Results_JSON> , > <http://www.w3.org/ns/formats/SPARQL_Results_CSV> , > <http://www.w3.org/ns/formats/SPARQL_Results_TSV> > . > ]] > > If you're OK with this, I'll plan to update PROV-AQ accordingly (but I > can't > guarantee to have it done until after next week, as I'm travelling to a > meeting > then.) > > #g > -- > > On 29/11/2012 18:53, Timothy Lebo wrote: > > all, > > > > On Nov 29, 2012, at 1:36 PM, Graham Klyne <Graham.Klyne@zoo.ox.ac.uk> > wrote: > > > >> We decided to drop the merely advisory material about how to use > SPARQL, and leave that to the FAQ. But discovery of a SPARQL endpoint got > forgotten in the change (I think it was never really specified previously). > >> > >> I think the cleanest solution would to to introduce another link > relation > > > > 1) > > > > I'm not fond of another link relation just to point to one specific > service technology. > > > > To handle "discovery of SPARQL endpoints" I think we should instead > combine: > > A) GET on service gives RDF description. (as already stated) > > B) http://www.w3.org/TR/sparql11-service-description/ > > > > to return: > > > > <service-URI> a prov:ProvenanceService, sd:Service ; > > additional vocabulary from B should be used further describe the service. > > The fact that <service-URI> is a sd:Service indicates that it is a > SPARQL endpoint. > > > > > > 2) > > > > The following citation seems to be inconsistent. > > > > [SPARQL-HTTP] > > Chimezie Ogbuji. SPARQL 1.1 Service Description. 2011, Work in progress. > URL: http://www.w3.org/TR/sparql11-http-rdf-update/ > > > > 3) > > > > In > http://dvcs.w3.org/hg/prov/raw-file/tip/paq/prov-aq.html#provenance-service-description > > I do not think the prov:provenanceUriTemplate property should be so > prominent. > > > > The first example: > > > > <service-URI> a prov:ProvenanceService ; > > prov:provenanceUriTemplate "service-URI?target={+uri}" . > > should be trimmed to: > > > > <service-URI> a prov:ProvenanceService ; > > > > with prov:provenanceUriTemplate being described as an OPTIONAL > description in subsequent discussion (as it stands now, it appears to be > required). > > This, too, is an assumption on how a service could be accessed. > > > > -Tim > > > > > > > > > > > > > >> for a SPARQL query endpoint (but to not get into details of how to > formulate the queries, other than to say that they are presented via SPARQL > HTTP protocol, and executed over provenance formulated as RDF according to > PROV-O). > >> > >> I'll raise an issue for this. > >> > >> #g > >> -- > >> > >> Tracker, this is issue 609 > >> > >> > >> On 29/11/2012 15:59, Paul Groth wrote: > >>> It's a good question. I wonder if we can somehow role this into > >>> provenance-service url? > >>> > >>> Paul > >>> > >>> > >>> On Thu, Nov 29, 2012 at 4:30 PM, Cresswell, Stephen < > stephen.cresswell@tso.co.uk > >>> <mailto:stephen.cresswell@tso.co.uk>> wrote: > >>> > >>> Hi,____ > >>> > >>> __ __ > >>> > >>> It still seems to me appropriate for PROV-AQ to include some > method by which > >>> publishers of a resource can indicate a SPARQL endpoint for > provenance > >>> queries.____ > >>> > >>> There was some discussion on this about a year ago, but it got > stuck on > >>> unresolved questions about named graphs, and doesn’t seem to have > made it > >>> into the document.____ > >>> > >>> __ __ > >>> > >>> Has there been a decision not to accommodate this, or is it still a > >>> possibility?____ > >>> > >>> __ __ > >>> > >>> > http://lists.w3.org/Archives/Public/public-prov-wg/2011Dec/0067.html____ > >>> > >>> > http://lists.w3.org/Archives/Public/public-prov-wg/2011Dec/0040.html____ > >>> > >>> > http://lists.w3.org/Archives/Public/public-prov-wg/2011Dec/0039.html____ > >>> > >>> __ __ > >>> > >>> Stephen Cresswell____ > >>> > >>> __ __ > >>> > >>> This email is confidential and may also be privileged and/or > proprietary to > >>> The Stationery Office Limited. It may be read, copied and used > only by the > >>> intended recipient(s). Any unauthorised use of this email is > strictly > >>> prohibited. If you have received this email in error please > contact us > >>> immediately and delete it and any copies you have made. Thank you > for your > >>> cooperation. > >>> > >>> The Stationery Office Limited is registered in England under > Company No. > >>> 3049649 at 1-5 Poland Street, London, W1F 8PR > >>> > >>> > >>> > >>> > >>> -- > >>> -- > >>> Dr. Paul Groth (p.t.groth@vu.nl <mailto:p.t.groth@vu.nl>) > >>> http://www.few.vu.nl/~pgroth/ <http://www.few.vu.nl/%7Epgroth/> > >>> Assistant Professor > >>> - Knowledge Representation & Reasoning Group | > >>> Artificial Intelligence Section | Department of Computer Science > >>> - The Network Institute > >>> VU University Amsterdam > >> > >> > > > > > -- -- Dr. Paul Groth (p.t.groth@vu.nl) http://www.few.vu.nl/~pgroth/ Assistant Professor - Knowledge Representation & Reasoning Group | Artificial Intelligence Section | Department of Computer Science - The Network Institute VU University Amsterdam
Received on Wednesday, 2 January 2013 15:05:03 UTC