Visual Studio Hacks

Generate Web Services Code #99

Chapter 13, Enhancing Visual Studio

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HACK

always a good thing, since Visual Studio assumes an XML-based RPC view

of Web Services.

There is an idea in Web Services development called contract-first or con-

tract-driven development. The basic idea is that, instead of letting Visual

Studio generate a WSDL file for you, you should write this WSDL file by

hand using a WSDL, XML, or text editor.

WSDL stands for Web Services Description Language. It is

an XML format used to describe a Web Service’s interface by

defining its operations and message exchange patterns. The

actual messages are defined using a schema definition lan-

guage like XSD.

Why would you want to write something by hand that Visual Studio will

usually generate for you? Letting Visual Studio generate your WSDL is kind

of like picking up a car on the lot and then letting the dealer take care of the

contract for you. Sure, you get the car—but who knows what you are com-

mitted to. By writing your WSDL first, you have complete control over how

your Web Service will be seen to the outside world, including its interface

and data structures. This is really just a continuation of the idea of contract-

driven development that has been around for years—the idea of first creat-

ing a contract that your object will implement and that your clients will con-

sume.

Writing the WSDL to your Web Services can be a task in