WSDL Requirements

1. WSDL should be at least as functional as IDL languages (or the
current Web) in its handling of persistent state that is known to both
clients and servers.

It should be possible for a service to return a URI that represents some
state (i.e. data and associated methods). It should be possible for the
resource associated with that URI to be strongly type-checked within
WSDL so that the set of methods applicable to it are predefined.

For example, a programming language should be able to statically type
check something like this:

po = service.createPO(...)
total = po.total()

Garbage collection is not required. The owner of a reference could
define its lifetime (just as with implicit objects managed by UUIDs, or
in the C programming language etc.).

If WSDL does not support this then it seems to me that it will not scale
to solving real-world problems.

2. I should also be able to hand a web service references to objects
created by other services, again by URL. Once again, it should be
possible to strongly type check these. The service should be able to
depend upon the strong type checking to know what methods will be
available on the data objects.

If WSDL does not support this then again it seems to me that it will not
solve real-world problems.

Summary:

WSDL needs a concept of reference with strongly typed-referents. The
reference syntax should be URIs. The referents must be describable
within WSDL as services in and of themselves.

 Paul Prescod

Received on Friday, 15 February 2002 17:13:40 UTC