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Adding a service reference to ASP.NET vNext/ASP.NET Core 1.0

Recently I started a new project in ASP.NET vNext aka ASP.NET 5, or as it is known since yesterday, ASP.NET Core 1.0. Since right now the framework is still in RC stage, there is next to no documentation to speak of… but that is a topic for another day.

But I had to add several WCF service references to the project to communicate with the back-end server. While we used to have a reasonably nice dialog for service references, it no longer exists in VS 2015 for ASP.NET Core 1.0. However – there is a plugin for adding “Connected services”, read about it at http://blogs.msdn.com/b/webdev/archive/2015/12/15/wcf-connected-service-visual-studio-extension-preview-for-asp-net-5-projects.aspx.

And I cannot stress this enough – while this plugin is in preview/current stage, do not use it. It is not capable of re-using code in referenced assemblies, which means it generates new classes instead of re-using old ones – and it cannot re-create generic classes. E.g. Response<User> becomes ResponseOfUserFq_SrmLzS, which is really not what is expected or wanted.

Instead, use good old svcutil from command line (you should probably create a cmd file, since you’ll probably want to update the service reference repeatedly):

svcutil.exe /l:cs /t:code /n:*,Your.Project.Desired.NameSpace /r:"fullpath-to-dto-assembly.dll" /r:"fullpath-to-model-assembly.dll" /r:"fullpath-to-vendor-assembly.dll" /o:Reference.cs http://localhost:9000/SomeServices/OurService.svc?fullwsdl

This will fetch the service info and create the service client (Reference.cs) and output.config while re-using all of the classes from assemblies specified with the /r keys. /n key allows you to specify the namespace for the generated code.

Note that the code generated with svcutil will require full .NET framework, not just .NET Core 1.0.

After I had figured out all of the above, I put my service configuration to wwwroot\web.config and expected it to work.

Nope. Enpoint configuration not found. No matter what I did, I could not get my development server (Kestrel) to read the <system.serviceModel> wwwroot\web.config. However, invalid XML in there gave an instant error… explain that?!

Googling was not all that helpful. There seems to be no way for ASP.NET Core to read service configuration from JSON files. But then I stumbled upon a lead – release announcement for ASP.NET 5 beta 7 had a single line announcing support of app.config when running on a full .NET framework.

And this is what I needed to do – instead of using good ol’ web.config (oh, how I hate thee!), you have to create an app.config in the root folder of your website (not wwwroot!), same place where project.json lives. You can just move the output.config there and rename it to app.config – and System.ServiceModel will now happily read the configuration from there.