Thursday october 28th Christian Weyer did a very good presentation to celebrate the 2nd aniversary of the Dutch user group dotned. Christian is a team member of thinktecture, just like Ingo Rammer who did a dotned presentation last july.

Christain's subject was "Contract first". In the new hype of web services and SOA we are told that it is all about the contract. First define the contract, after that you can implement it, for instance in a webservice. The problem is that all tools focus on implementation. Create a new webservice in Visual Studio and you are thrown right into the implementation code. Eeven in VS 2005 team system there is no tool for defining a contract.

Contract designers are nothing new, take stuff like IDL the interface description language for COM. Mmyself I have spent days and days in the Delphi type library editor which is a visual tool to edit an IDL out of which a typelibrary and an implementation skeleton is generated. Christain demonstrated an add on for VS he is building himself. It works with xsd schemas, not just for the data types your service is working with but also for the operations your service supports. It was a clear story full of revelations. The full story and the tool can be found here on the thinktecture website. Absolutely recomended !

Peter