- From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
- Date: Fri, 03 Jun 2011 13:34:38 +0100
- To: Paul Groth <pgroth@gmail.com>
- CC: Graham Klyne <GK@ninebynine.org>, Luc Moreau <L.Moreau@ecs.soton.ac.uk>, W3C provenance WG <public-prov-wg@w3.org>
On 01/06/2011 09:16, Paul Groth wrote: > The question is, whether > 1) we build up from talking about resource state and have conventions > for dealing with resources that are dynamic; or > 2) the other way around. We take resources and then add additional > properties to discuss things like states. > I think that this summarize nicely the discussion we had about resources so far. khalid > I think you're advocating for 2). > > But in the end the question is really we should capture all notions. > Would you agree that resource and resource state are resource > representation are all important notions we need to be able to discuss. > > Is that correct? > > Thanks, > Paul > > > > > Graham Klyne wrote: >> Luc Moreau wrote: >>> Hi Graham, >>> >>> Isn't it that you used the duri scheme to name the two resource states >>> that exist in >>> this scenario? >> >> That is a possible way of describing it, but the essence of what I >> suggest is >> that the "states" (or "snapshots") are themselves resources. >> >>> In your view of the web, is there a notion of stateful resource? Does >>> it apply here? >> >> Resource state is an architectural concept in the web. Indeed, it's so >> fundamental that the notion is used throughout >> http://www.w3.org/TR/webarch/ >> without actually being defined, as far as I can tell. (Other than >> indirectly by >> reference to Fielding's thesis.) >> >> But not all resources have dynamic state. Indeed, probably most >> resources on >> the web are static. >> >> What I'm trying to do is avoid a layer of modelling complexity that I >> don't >> believe is needed: I think we can say all we need to say by just talking >> about >> resources. And in some cases, I think that talking about non-resources >> can lead >> to inconsistencies or awkwardness (sorry, no example to hand.) >> >> To some extent, this pushes the static/dynamic discussion to a different >> place, >> because in some cases the type of a resource may be significant. But I >> see that >> as a useful extension point in any case, when discussing possibly >> conflicting >> models of provenance and associated inference. What I'd really like to >> do is >> simplify the *core* model until there's nothing there for the different >> provenance models to disagree about. >> >> ... >> >> Tangentially related, I just read through Yolanda's slides >> (http://www.w3.org/2005/Incubator/prov/wiki/images/0/02/Provenance-XG-Overview.pdf), >> >> and followed up on some of the associated reports, and my feeling is >> that there's serious potential here for scope creep. >> >> One point in which I am in very strong agreement, indeed, I think it's >> probably the most important thing for us as a working group, is: >> >> Slide 36: >> "The exchange language should have a low entry point to facilitate >> widespread adoption, therefore it should be easy to do simple things" >> >> I think this is crucial the the eventual success of this group's work >> (by which I don't mean successfully advancing to REC status, but >> creating specifications that will actually be used in the web at large). >> The provenance problem is too important to mess it up my making it too >> complicated for developers to get started. >> >> So, I think that at a basic level of provenance on the web, we want to >> avoid talking about states, and snapshots, and other constructs that are >> not directly relevant to a web developer creating an application to >> record or use provenance information. I think the notion of "resource", >> interprted broadly per AWWW, etc., allows us to do that. Building upon a >> very simple core model, the subtleties can be added throug refinement of >> the core concepts. But if the core concepts are not so simple that >> developers can easily generate provenance information, this group's work >> could end up like a magnificently engineered car with no roads to >> drive on. >> >> #g >> -- >> >>> On 31/05/11 23:57, Graham Klyne wrote: >>>> Luc Moreau wrote: >>>>> Graham, >>>>> >>>>> In my example, I really mean for the two versions of the chart to be >>>>> available at >>>>> the same URI. (So, definitely, an uncool URI!) >>>>> >>>>> In that case, there is a *single* resource, but it is stateful. >>>>> Hence, there >>>>> are two *resource states*, one generated using (stats2), and the >>>>> other using (stats3). >>>> >>>> Luc, >>>> >>>> I had interpreted your scenario as using a common URI as you explain. >>>> >>>> But there are still several resources here, but they are not all >>>> exposed on the web or assigned URIs. I'm appealing here to anything >>>> that *might* be identified as opposed to things that actually are >>>> assigned URIs. (For example, the proposed duri: scheme might be used >>>> - http://tools.ietf.org/id/draft-masinter-dated-uri-07.html) >>>> >>>> (And the URI is perfectly "cool" if it is specifically intended to >>>> denote a dynamic resource. A URI used to access the current weather >>>> in London can be stable if properly managed.) >>>> >>>> (I think this is all entirely consistent with my earlier stated >>>> positions.) >>>> >>>> #g >>>> -- >>>> >>>>> Of course, if blogger had used cool uris, then, c2s2 and c2s3 would >>>>> be different resources. >>>>> >>>>> Luc >>>>> >>>>> On 05/31/2011 02:25 PM, Graham Klyne wrote: >>>>>> I see (at least) two resources associated with (c2): one generated >>>>>> using (stats2), and other using (stats3). We might call these >>>>>> (c2s2) and (c2s3). >>>>> >>> >> >> >> > >
Received on Friday, 3 June 2011 12:35:07 UTC