- From: Glen Daniels <gdaniels@sonicsoftware.com>
- Date: Tue, 19 Jul 2005 14:17:45 -0400
- To: <public-ws-addressing@w3.org>
Hi all: Currently there is no processing model for EPR extensions, and the core spec says specifically that a processor will ignore any extensions which it does not recognize or understand [1]. This means that there is no way for the minter of an EPR to express any kind of mandatory extension, which has serious consequences in the areas of versioning, policy, and the scope of possible extensions - it's hard to design/use a meaningful extension if you have no assurance it's not going to be ignored. Some example use-cases that are not adequately supported can be found in [2]. We feel that the decision not to include a "mustUnderstand" or "required" attribute and a simple processing model (i.e. "don't use the EPR if you don't understand an extension marked mandatory") was a serious mistake which should be rectified. It's a simple thing to add, it is very much in line with Web Services patterns (c.f. SOAP "MustUnderstand" and WSDL "required") and would enable many usage scenarios which are currently impossible. To be clear, what we are proposing would be a) the addition of a "wsa:required" attribute, which would be allowed on all immediate children of an endpointReference and all immediate children of the <metadata> element, and b) a description of the rules associated with this attribute. Thanks, Glen Daniels, Sonic Software Anish Karmarkar, Oracle Corporation David Orchard, BEA Systems Rebecca Bergersen, IONA [1] http://dev.w3.org/cvsweb/~checkout~/2004/ws/addressing/ws-addr-core.html ?content-type=text/html;%20charset=utf-8#eprextensibility [2] http://www.w3.org/mid/80A43FC052CE3949A327527DCD5D6B27011FA76A@MAIL01.be dford.progress.com
Received on Tuesday, 19 July 2005 18:17:37 UTC