W3C home > Mailing lists > Public > public-rdf-dawg@w3.org > October to December 2012

RE: Ambiguity between SPARQL 1.1 RDF protocol query via GET and SD retrieval

From: Polleres, Axel <axel.polleres@siemens.com>
Date: Tue, 9 Oct 2012 09:29:49 +0200
To: "greg@evilfunhouse.com" <greg@evilfunhouse.com>, "chimezie@gmail.com" <chimezie@gmail.com>, "sandro@w3.org" <sandro@w3.org>
CC: "public-rdf-dawg@w3.org" <public-rdf-dawg@w3.org>
Message-ID: <9DA51FFE5E84464082D7A089342DEEE80149E3ECC526@ATVIES9917WMSX.ww300.siemens.net>
Hi,

@sandro, is it ok to fix editorial things like aligning wording and maybe putting in some anchors
to cross-references terminology in the last transition from PR to Rec still?

Axel


> -----Original Message-----
> From: Gregory Williams [mailto:greg@evilfunhouse.com]
> Sent: Montag, 08. Oktober 2012 18:41
> To: Chime Ogbuji
> Cc: SPARQL Group
> Subject: Re: Ambiguity between SPARQL 1.1 RDF protocol query
> via GET and SD retrieval
>
> On Oct 6, 2012, at 1:07 PM, Chime Ogbuji wrote:
>
> > While porting over my implementation of the SPARQL 1.1 RDF
> protocol, I noticed that the language in the Service
> Description specification about how a service description
> document is dereferenced is a bit ambiguous.
> >
> > "SPARQL services made available via the SPARQL Protocol
> should return a service description document at the service
> endpoint when dereferenced using the HTTP GET operation"
> >
> > Whereas the SPARQL 1.1 RDF Protocol document says:
> >
> > "Protocol clients may send protocol requests via the HTTP
> GET method. When using the GET method, clients must URL
> percent encode (http://www.ietf.org/rfc/rfc3986.txt) all
> parameters and include them as query parameter
> (http://www.ietf.org/rfc/rfc3986.txt) strings with the names
> given above"
> >
> > Under the query string parameters column for this binding
> it says: "query (exactly 1)".
> >
> > Unless I've missed text elsewhere that clarifies this,
> reading both as they are written begs the question about
> whether a query via GET binding request SHOULD return an SD
> document. My assumption is that the distinction is between a
> GET request to the service endpoint *without* a query
> parameter versus a request *with* this parameter - returning
> an SD document if the query parameter is not provided.
> >
> > This distinction should be made explicit. Some suggested
> text (in SD specification):
> >
> > "[...] should return a service description document at the
> service endpoint when dereferenced using the HTTP GET
> operation without any query parameter strings provided"
>
> I agree that the language here could be made better by being
> more specific. In looking this over, I also noticed that the
> terminology between the two documents has drifted a bit
> (which is a bit embarrassing since I edited both). SD says:
>
> """
> A SPARQL [Protocol] service is commonly referred to as a
> "SPARQL endpoint".
> """
>
> while Protocol has two different definitions for "Service"
> and "Endpoint":
>
> """
> SPARQL Protocol service
> An HTTP server that services HTTP requests and sends back
> HTTP responses for SPARQL Protocol operations. The URI at
> which a SPARQL Protocol service listens for requests is
> generally known as a SPARQL endpoint. (Also known as: service)
>
> SPARQL endpoint
> The URI at which a SPARQL Protocol service listens for
> requests from SPARQL Protocol clients.
> """
>
> Does anyone (esp. chairs) think fixing this before the
> upcoming publication would be a problem (or perhaps it's
> something that could be fixed post-publication)? I don't
> think fixing this is a substantive change as I believe the
> spec text, examples, and tests are all pretty clear about
> what is meant, but certainly don't want to cause problems for
> anyone who thinks otherwise.
>
> thanks,
> .greg
>
>
>
Received on Tuesday, 9 October 2012 07:30:20 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:15:49 GMT