- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Wed, 26 Jan 2005 17:33:28 +0000
- To: kendall@monkeyfist.com
- CC: public-rdf-dawg@w3.org
Kendall Clark wrote: > Folks, > > We kicked this issue around in Espoo, especially related to our > service description language modeling efforts. I'm not sure I > understand what the best opportunity for consensus is, but presently > in the protocol document we've published, the design looks something > like this (in the HTTP binding): > > 1. queries are named by a "query" parameter > 2. the type of query is named by a "query-lang" parameter, the value > of which is a URI that identifies the query language; there is no > list of such URIs nor short names in the document presently > 3. if "query" is present, "query-lang" *must* be present too > > One of the designs I can remember being proposed or discussed in Espoo > was to "overload" (for lack of a better term) a single parameter, such > that it conveyed the semantics of the present "query" and > "query-lang". In other words, this design proposes a single parameter, > the name of which indicates the query language type, and the value of > which is (presumably) a legal sentence of that query language. For > example, "sparql" or "rdql". > > Further, the identity of this string would be encoded in the service > description and would have to be discovered (at least once) by > requesters wishing to convey queries to that service; presumably, > though we cannot enforce this, it would be a good practice for that > parameter name to change as infrequently as possible. Further, again > presumably, the parameter name could be cached by requesters, subject > to the ordinary caching and resource-freshness issues vis-a-vis HTTP. Please factor in the caching mechanisms of an application programmer reading a spec for the service instance of interest and writing the parameter names into the code. Andy > > (Putting my WG member hat back on for a second, I'm not sure why > discovering this *one* parameter name is good, but discovering other > parameter names is somehow a bad design. Will have to chew on that one > further, I guess.) > > I believe the other designs discussed in Espoo are variations -- > different parameter names, as I recall -- of the design in the present > protocol document. > > Finally, various WG members took ACTIONs to work on (parts of) an RDF > vocabulary for describing provisioning and service details of SPARQL > query processors and queryable RDF graphs. I believe there was > consensus that such a language should be included as part of the > protocol document. > > Accordingly, and in order to provide a *bit* of coordination, I'm > adding a section to my private draft of that document, which I'll > update publicly by Friday, called "SPARQL Protocol Description Language" > and using the acronym "SPDL" for that vocabulary. YMMV, of course, and > I welcome other suggestions and feedback. > > Best, > Kendall Clark >
Received on Wednesday, 26 January 2005 17:35:32 UTC