Comments on: Design for testability – WCF proxies

By: Nigel Sampson

Nigel Sampson — Thu, 05 Nov 2009 20:38:23 +0000

Ahhh, now it makes a lot more sense.

Thanks for that

By: malovicn

malovicn — Thu, 05 Nov 2009 14:28:22 +0000

It is probablly related to the fact that "we" don’t have in our code service contract as separate interface but instead implementation class gets decorated by attributes.

If you look at Reference.cs in my sample you would find UserService interface (note NOT IUserService)

public interface UserService {

System.IAsyncResult BeginGetUsers(AsyncCallback callback, object asyncState);

ObservableCollection EndGetUsers(IAsyncResult result);

}

The main difference between our two approaches is that your comes out of box but requires one to use the BeginXXX, EndXXX syntax while mine requires some work but allows using xxxAsync + xxxCompleted event handler.

IMHO, "the more the merrier" so it is good we came out with two different approaches

By: Nigel Sampson

Nigel Sampson — Thu, 05 Nov 2009 04:17:52 +0000

Hey again, been trying pretty hard to generate a proxy that didn't contain an interface with no luck.

Did find this page msdn.microsoft.com/.../ms733133.aspx which shows the output of svcutil which includes the two interfaces.

Not sure why you (and a few of my readers) aren't getting that interface. If you do find out can you let me know at nigel.sampson@compiledexperience.com

By: Nigel Sampson

Nigel Sampson — Tue, 03 Nov 2009 21:31:53 +0000

I've been back and double checked it (running Visual Studio 2008 with Silverlight 3) and Reference.cs contained two interfaces ICocktailService and ICoctailServiceChannel. Haven't used the latter, but the former contained the BeginX and EndX method pairs (but not the events exposed by the actual implementation CocktailServiceClient).

The post is at compiledexperience.com/.../Blendable-MVVM-WCF-and-Asynch-Data-Sources but I didn't put the generated interface in (didn't think it was overly special), but had a few emails about it not being generated for others so I'm looking into why.

It's really strange, initially thought it was because both server and client were in same solution, but tried from a seperate solution to get the interface.

Will comment here when I have some definate answers (I've just checked and my work computer is generating interfaces as well).

Could it be .net 3.5 SP1?

By: malovicn

malovicn — Sun, 01 Nov 2009 20:15:17 +0000

Nigel,

I was doing this "more then a few times" in both VS2008 and VS2010 with Silverlight, Wpf and ASP .NEt and never seen that IUserServiceClient interface

What I have seen is |IUserService| (being a service contract) but in Silverlight async scenarios (and WPF if you want to have easy multy targeting scenario) that result with that interface having pairs BeginXXX and EndXxx etc -> totally different API then the one from client I am using in my post

Can you please post a link to your blog post where you presented your case? I am dying to see that

By: Nigel Sampson

Nigel Sampson — Sun, 01 Nov 2009 10:13:27 +0000

Excellent post, thanks a lot. One thing I found interesting though was that I wrote something similar around WCF and MVVM not long ago and found that WCF proxy had a pregenerated interface already on it.

What's strange is that was almost exactly the same as your service. Some tooling difference? Woud love to know your opinion