RE: Issue 6413 - just thinking

Doug,

> The question is, how do you get more granularity if the service won't give you an EPR to something lower down?

That is a fair question.  But an equally fair question is, why would the service choose to provide a complete fragment access implementation to get at "lower down" sub-resources rather than provide an EPR to something lower down?  What is the use case that suggests its easier/safer/better/... to provide "lower down" access via fragment access, rather than to provide it via EPRs?

--Geoff


From: public-ws-resource-access-request@w3.org [mailto:public-ws-resource-access-request@w3.org] On Behalf Of Doug Davis
Sent: Wednesday, May 06, 2009 3:56 PM
To: public-ws-resource-access@w3.org
Subject: RE: Issue 6413 - just thinking


Geoff Bullen <Geoff.Bullen@microsoft.com> wrote on 05/06/2009 05:35:24 PM:
> Fragment access provides a generic framework for accessing fragments
> of a resource, but the client still has to have intimate knowledge
> of the way in which fragments are supported within the particular
> resource it is talking to.  How does the client gain such knowledge?
> There is no method called generateFragments that will return
> fragment definitions, so that the client can use XPath to access them.
>
> If it is OK for the client to know the details of how to setup an
> appropriate XPath query, why is it not OK for the client to know how
> to generate, say, a URI that represents the fragment (e.g. http:
> /.../myresource?section=a&subsection=b)

You need to talk with your WSA team.  EPRs are owned by the minter,
in this case the service.

> As a side note, how did the client get the top level EPR in the
> first place?  Could you not get the fragment EPRs the same way?

Sure and that's ok - as long as the EPR is opaque to the client.  As I said,
this can be done today no change is needed.

> What is actually the difference between a "resource" EPR and a "fragment" EPR?

Nothing and that's actually my point.  Once the client has an EPR to a resource,
its just a resource.  The question is, how do you get more granularity if the
service won't give you an EPR to something lower down?  ta da... fragments  ;-)

-Doug