Add 'Keyed by Service type' ServiceBehavior support in CoreWCF

Introduction

The CoreWCF 1.6.0 release introduced a new feature that allows to apply a ServiceBehavior registered in DI to only one Service when hosting multiple services in a single host.

Implementation

This feature uses the IKeyedServiceProvider capabilities introduced in .NET8 and requires the registration of the ServiceBehavior type to be done using the IServiceCollection.AddKeyedSingleton<TService, TImplementation>(object? serviceKey) extension method.

Example

In the below Startup class, the call to AddKeyedSingleton<IServiceBehavior, MyServiceBehavior>(typeof(ReverseEchoService)) apply MyServiceBehavior to ReverseEchoService only.

private class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddSingleton<EchoService>();
        services.AddSingleton<ReverseEchoService>();
        services.AddKeyedSingleton<IServiceBehavior, MyServiceBehavior>(typeof(ReverseEchoService));
        services.AddServiceModelServices();
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseServiceModel(builder =>
        {
            builder.AddService<EchoService>();
            builder.AddServiceEndpoint<EchoService, IEchoService>(new BasicHttpBinding(), "/EchoService.svc");
            builder.AddService<ReverseEchoService>();
            builder.AddServiceEndpoint<ReverseEchoService, IReverseEchoService>(new BasicHttpBinding(), "/ReverseEchoService.svc");
        });
    }
}