ASP.NET Core–Configuring a WCF service

In an ASP.NET Core application(using the full .NET framework) we had to consume a WCF service.

Should be easy right? Unfortunately it turned out that be more work than I expected. In a first post I explained the steps how to generate a Client Proxy, this post is about  setting the configuration.

WCF configuration can be a daunting beast with a lot of options and things that can go wrong. The code generated by the proxy hardcodes (some part) of the configuration in the WCF proxy and provides you a partial method to override it but that’s not the approach we want to take.

	static partial void ConfigureEndpoint(System.ServiceModel.Description.ServiceEndpoint serviceEndpoint, System.ServiceModel.Description.ClientCredentials clientCredentials);
	public Service1Client() :
	base(Service1Client.GetDefaultBinding(), Service1Client.GetDefaultEndpointAddress())
	{
	this.Endpoint.Name = EndpointConfiguration.BasicHttpBinding_IService1.ToString();
	ConfigureEndpoint(this.Endpoint, this.ClientCredentials);
	}

view raw reference.cs hosted with ❤ by GitHub

I know we’ll host the WCF service in IIS, so adding a web.config and putting the configuration logic over there sounds nice…

Let’s try that:

• Open the generated proxy reference file  and remove the call to Service1Client.GetDefaultBinding() and Service1Client.GetDefaultEndpointAddress() in the constructor. (Note: this is only for testing purposes)

• Right click on your ASP.NET Core project and add a web.config file.
• Right click on the web.config and choose Edit WCF configuration.

• Go to the Client section and choose Create a New Client…

• Follow the steps through the Wizard. After completing it you should have something like this inside your web.config:

	<configuration>
	<system.serviceModel>
	<client>
	<endpoint address="http://localhost:32457/service1.svc" binding="basicHttpBinding"
	bindingConfiguration="" contract="ServiceReference1.IService1"
	name="" kind="" endpointConfiguration="" />
	</client>
	</system.serviceModel>
	</configuration>

view raw web.config hosted with ❤ by GitHub

• Let’s now try to create a client proxy instance and execute a call:

	public void Configure(IApplicationBuilder app, IHostingEnvironment env)
	{
	if (env.IsDevelopment())
	{
	app.UseDeveloperExceptionPage();
	}
	app.Run(async (context) =>
	{
	using (var client = new Service1Client())
	{
	await client.DoWorkAsync();
	}
	await context.Response.WriteAsync("Hello World!");
	});
	}

view raw Startup.cs hosted with ❤ by GitHub

• Unfortunately, this didn’t work and we end with an exception when we try to run our application:

• If that doesn’t work, where should we put this configuration? (And yes, I know I can do everything through code but that is not what I want here).
• An ASP.NET Core project is an executable behind the scenes. The only thing that IIS does is forward the request to Kestrel that invokes the DotNet process.
• This executable has its own configuration file that is generated for you out of the box behind the scenes.

• If you want to change this config, you have to add an app.config instead of a web.config to your project. Let’s just rename the file, rebuild our project and try again…

• This time it works!