NEW ISSUE: use RDDL instead of XML Schema at the namespace URI?

Background:

As many of you are aware, there is an ongoing debate on what kind of
resource should be placed at the namespace URI.  The TAG has been unable
to recommend a practice in this area, despite a lot of discussion.

The W3C, AIUI, has a policy that there should be some document at the
namespace URI, but does not enforce a particular format.  In general
namespace URIs seem to return HTML documents.

There are also many proponents of RDDL [1], which is simply an XHTML
document with some machine-processable XLinks in it pointing to
associated resources like schemas.

Justification:

One advantage of RDDL is that it would enable one to discover, through
the namespace URI, a number of schemas for the namespace.  This is
especially interesting when errata are taken into account.  The WS-I BP
promulgated some fixes to the WSDL 1.1 schema, but since it is also
desirable to have a stable document at the namespace URI, it published
alternative dated versions with various fixes in them, and pointed to
those dated versions from the spec.  It might have been simpler and more
discoverable to find all the related (dated) schemas through a RDDL
document at the namespace URI.

Proposal:

Place a RDDL document at each of the namespace URIs defined by WS-A.
Provide a "latest schema" link as well as dated links to the schema.
State in the document that the resources (schemas) at the dated links
are immutable, the list of dated schemas may grow to incorporate fixes,
and the latest schema link will always point to the latest.

A necessary related change to the specs is for sections of the specs
which say that a schema is available "at" the namespace URI to be
updated to say "through" the namespace URI, or some such.

Caveat:

Microsoft feels there are some benefits to this proposal to the extent
that it doesn't take us down the rabbit hole of attempting to solve the
general problem of what should go at a namespace URI.  We would prefer
the status quo to spending significant amounts of time on this subject.

[1] http://www.rddl.org/

Received on Thursday, 7 April 2005 23:34:13 UTC