- From: David Orchard <dorchard@bea.com>
- Date: Thu, 22 Jan 2004 09:41:16 -0800
- To: <www-ws-desc@w3.org>
From my blog entry, [0]: I've finally published the opus on what can and could be done to provide compatible evolution of Schemas [1] . It lists all the ways people can do extensibility and versioning now, such as wildcards (##other, ##any, ##targetnamespace), Extension Elements, and Type Extension. And then it goes into a number of things, including potential changes to Schema, that could be done to better meet the requirements for loosely coupled Web components. I argue in Web Services = or != Distributed Objects [2] that Schema authors tend to make tightly coupled Web services because they can't fully version or evolve them. I proposed one simple schema design with related rules in Versioning XML Languages [3], but I didn't have time to do justice to all the current and possible techniques. That deficiency I consider rectified. I've also made a collection of links to mine and others (notably David Bau) writings on extensibility and compatibility in my compatibility index page [4]. You can see the relationship amongst the writings on the importance of loose coupling, how extensibility and versioning enable it, what you can and can't do with XML schema today. I hope this material helps in discussions about compatible evolution of web service descriptions. I would also be glad to do a tutorial or overview at the WSDL WG F2F next week. Cheers, Dave Orchard [0] http://www.pacificspirit.com/blog/2004/01/19/providing_compatible_schema_evo lution [1] http://www.pacificspirit.com/Authoring/Compatibility/ProvidingCompatibleSche maEvolution.html [2] http://www.pacificspirit.com/blog/2004/01/12/web_services_or_distributed_obj ects [3] http://www.xml.com/pub/a/2003/12/03/versioning.html [4] http://www.pacificspirit.com/Authoring/Compatibility/
Received on Thursday, 22 January 2004 12:40:02 UTC