RE: property value clarification

Albert Lunde wrote:
"This may be reasonable in some other context; but right now, it looks
me,
like WEBDAV intends to treat dead properties as containers which can be
set
to arbitrary (internationalized) string values, with no further
knowledge
of data type and symantics."

I don't believe that is true. If that were true, then query 
would be hopeless. One can not do query in a satisfactory
way without facing the data types issue. However, query is 
not hopeless, because your assertion is not true. There are, 
in fact, data types underlying DAV. Otherwise, the model 
would be just junk and should be thrown out. The WebDAV draft
just does not address data types explicitly. It leaves data 
types to be developed by other DAV efforts, and their
expression in XML to XML committees.

"Bringing in the "XML Data" datatypes you refer to would be 
a significant change to WEBDAV."

I don't believe that it is a change to WebDAV at all. Data 
types were there underneath WebDAV all along, so it is not 
a change to WebDAV. Note that data types are being brought 
into *XML* -- not just WebDAV, *all XML* -- by an XML 
committee. XML Data is a change to XML, not WebDAV. Given 
the existence of XML Data and the fact that WebDAV chose XML 
as it serialization format, it doesn't make sense for WebDAV
to go off and express datatypes some other way. They
are simply already there in XML "for free".

Due to the fast pace of the internet, standards generally
can not create interdependencies on each other. So, WebDAV
has no dependency on XML Data. However, certain outcomes
of related standards efforts are generally anticipated, 
and some effort made to mesh smoothly with them when they 
complete. That is also the reason why only a piece of the 
whole DAV design is in the WebDAV draft. Other pieces are 
in other drafts (e.g., Advanced Collections, Versioning, 
DASL, etc.). That is also partly why the property model 
is not completely explained in the WebDAV draft. 

DAV is a very large design coming out in pieces. We need to 
let it come out in pieces. If we wait for all the pieces, 
it would take several years at best, and more than likely 
it would fail.

Alan Babich

P.S.: A well written white paper that motivates and explains
the design and the reasoning behind the tradeoffs might
help the discussions. Then you could see what the model is
and what the stuff that isn't in the drafts is supposed to 
be. Such a draft would be extremely valuable to newcomers.
However, nobody has the time to write it.

Received on Sunday, 1 November 1998 23:45:50 UTC