Generating WSDL Without ASP.NET

Because wsdl.exe generates classes that don't look exactly like we want them to, I've set up a process at my client to generate custom proxies. Right now, we do this as a partly manual process - we've got a simple script that downloads the WSDL from a set of web services we've developed, then generates the default proxies by running wsdl.exe against them. Then we make some simple hand edits against them to make them look how we want them to.

There are two problems with this process:

1. It requires hand editing the files every time we want to make a change.


2. The turnaround sucks - we have to deploy the web service somewhere before we can get the WSDL.

The first one I'll fix later. It's pretty easy to do right now, since most of the changes are just removing code. At some point I'll cobble together some sort of sed script or something.

The second one is sort of a pain at the moment, though. We're using Continuous Integration, which is great because it means every time someone makes a change, we get a fully tested and installed version of the product running on a web farm about twenty minutes later. But because that's currently the only way we have of deploying (setup is somewhat complex), it means that if someone adds a [WebMethod], they have to wait 20 minutes for the deployment before they can download the wsdl and update the custom proxies.

I thought it would be pretty nice if instead there was some way to generate WSDL directly from the web service assemblies. Well, after poking around a bit with Reflector, and with a little help from Tim, I'd figured out the incredibly easy code to do exactly this. Assuming you have a web service class called MyService, the following code will spew the WSDL for it to the command line:

ServiceDescriptionReflector reflector = new ServiceDescriptionReflector();
reflector.Reflect(typeof(MyService), "http://localhost/vdir/Foo.asmx");

if (reflector.ServiceDescriptions.Count > 1){
  throw new Exception("Deal with multiple service descriptions later");
}

XmlTextWriter wtr = new XmlTextWriter(Console.Out);
wtr.Formatting = Formatting.Indented;
reflector.ServiceDescriptions[0].Write(wtr);
wtr.Close();

The URL that appears in the call to Reflect is not used except to populate the address element in the WSDL.

It'll be the work of minutes to roll this code up into a little EXE that takes the class name on the command line. I'll probably add an option to reflect over all classes in an assembly, looking for anything with a [WebMethod] attribute on it somewhere and emitting that, too.