It [hand written WSDL] may be a better way, but the tool support is not there. Why don't web service dev tools have a WSDL editor? Why do we start with implementation instead of the interface? Some third party WSDL-editing tools are mentioned, but he says that WSDL is only part of the problem. Complex web services have lots of files, lots of manual work to make stuff look seamless.

In a nutshell: It's better to start with the interfaces, and the tools need to support programmers who want to work this way.

[Brian Jepson]

Don Box made the same point last March, I think the exact quote was "WSDL.EXE /server is the unsung hero of web service programming". The problem is that hand writing WSDL is just unbelievably painful. I got started doing interface based programming about 6 years ago, doing CORBA. CORBA IDL was OK to work with, not too hard to learn, easy to edit by hand. Then doing COM: about an order of magnitude in complexity. The wizards start looking nicer and nicer. Now WSDL, which is maybe not so complex, but is so ridiculously verbose that you'd get carpal tunnel just typing a simple contract. Tools would be really nice and would support this form of programming, but I think it's too late. The auto-generated WSDL that all the good toolkits provide is too good, and too easy. And the problem with the previous interface based systems is that you need to set up a build step to generate server implementation stubs, and then you need to make sure your server implementation code stays in sync. So you really have to get the interface right early on, or figure out a way to force the interface to stay in sync. Visual C++ did a pretty good job with this; you could do COM objects without ever seeing the IDL. The point is that WSDL matters; what goes on the wire matters. But unless the tool vendors do something to support that idea, we're going to have a lot of lazy programmers doing the wrong thing.