RE: DASL Charter

On the third hand we will want DASL to be able to fully leverage XML typing,
even if this means DASL won't work properly against non-XML native systems.
This is a perfect example of a feature that DAV provides that we want to be
able to fully leverage, even if it means not working with other systems.

		Yaron

> -----Original Message-----
> From:	Jim Whitehead [SMTP:ejw@ics.uci.edu]
> Sent:	Tuesday, March 03, 1998 2:44 PM
> To:	'Surendra Reddy'; Alex Hopmann; www-webdav-dasl@w3.org
> Subject:	RE: DASL Charter
> 
> Unfortunately, I think the text "other interoperable HTTP applications" is
> 
> *way* too broad.  This could be construed to mean, among other things:
>   - Internet Printing Protocol (IPP) properties
>   - any RPC-like protocol bolted-on to (passed through) POST
> 
> I had an "aha" moment when Alex wrote:
> 
> > Also, those two queries look identical. Please keep in mind that DAV
> > has a totally open ended property framework, so <d:dma-guid> is a
> > property just like any other.
> 
> The emerging consensus on this list appears to be that DASL should support
> 
> searching on repositories whose data model is equivalent (or can be made
> to 
> look equivalent) to the DAV resource data model (i.e., a body plus 
> properties which are name, value pairs).  So, my stab at rewriting the 
> Charter is to modify the first sentence, which now says:
> 
> > The goal of this working group is to provide searching
> > interoperability among the variety of underlying storage
> > systems whose data can be exposed by the WEBDAV extensions to
> > HTTP.
> 
> Change this to read:
> 
> The goal of this working group is to provide searching
> interoperability among the variety of underlying storage
> systems whose data can be exposed (viewed? are compatible with?)
> through the HTTP plus WebDAV data model.
> 
> So, if, as you and Jim Davis have suggested, the properties of a
> repository 
> can be expressed in XML as name, value pairs where the name is a URI
> (which 
> can be an encoding of the property namespace of an underlying repository),
> 
> and the value can be encoded as well-formed XML, then the properties are 
> compatible with the HTTP + WebDAV  resource data model, and are amenable
> to 
> searching via DASL.
> 
> One concern I have with cross-repository searching is the problem of 
> typing.  As near as I can tell, WebDAV is the only system of those 
> mentioned in this thread which uses XML for its typing.  Others, like DMA,
> 
> have a type system for properties, and it seems to me this type system 
> might creep into the search syntax if we're not careful.  On the other 
> hand, by using XML to encode search syntax and search results, perhaps we 
> can avoid this entire issue.
> 
> - Jim
> 
> On Tuesday, March 03, 1998 10:07 AM, Surendra Reddy 
> [SMTP:skreddy@us.oracle.com] wrote:
> >      Alex,
> >
> >         |:The goal of this working group is to provide searching
> >         |:interoperability among the variety of underlying storage
> >         |:systems whose data can be exposed by the WEBDAV extensions to
> >         |:HTTP. The working group will define HTTP extensions that
> enable
> >         |:server-executed queries to locate resources based upon their
> >         |:property values and text content.
> >
> >     I would recommend the following changes to DASL charter.
> >
> >     "The goal of this working group is to define and develop an
> >     extensible  DAV Searching and Locating protocol as
> >     extensions to HTTP.The working group will define HTTP
> >     extensions that enable  server-executed queries to locate resources
> >     based upon their property values and text content as exposed by
> >     DAV as well as other interoperable HTTP applications."
> >
> >      With this change incorporated, I am full agreement with DASL 
> charter.
> >
> >     Appreciate your comments.
> >
> >  Best regards,
> >
> > Surendra

Received on Tuesday, 3 March 1998 19:58:01 UTC