SIgnalR - An item with the same key has already been added - wcf

Question

i am having an issue regarding a signalr (version 1.2.2. I cannot update toto 2+)/autofac/Nunit implementation. I am using an MVC client with a WCF service whixh pushes notifications to client. When I' m running the app using the web client and the service everything works as expected. When i try to test my service through NUnit everytime i try to create the hubcontext
GlobalHost.ConnectionManager.GetHubContext<ProductHub>()
i get
An item with the same key has already been added.
here is the full stack trace
at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
at System.Linq.Enumerable.ToDictionary[TSource,TKey,TElement](IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector, IEqualityComparer`1 comparer)
at Microsoft.AspNet.SignalR.Hubs.ReflectedHubDescriptorProvider.BuildHubsCache()
at System.Lazy`1.CreateValue()
at System.Lazy`1.LazyInitValue()
at System.Lazy`1.get_Value()
at Microsoft.AspNet.SignalR.Hubs.ReflectedHubDescriptorProvider.TryGetHub(String hubName, HubDescriptor& descriptor)
at Microsoft.AspNet.SignalR.Hubs.DefaultHubManager.c__DisplayClass1.b__0(IHubDescriptorProvider p)
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
at Microsoft.AspNet.SignalR.Hubs.DefaultHubManager.GetHub(String hubName)
at Microsoft.AspNet.SignalR.Hubs.HubManagerExtensions.EnsureHub(IHubManager hubManager, String hubName, IPerformanceCounter[] counters)
at Microsoft.AspNet.SignalR.Infrastructure.ConnectionManager.GetHubContext(String hubName)
at Microsoft.AspNet.SignalR.Infrastructure.ConnectionManager.GetHubContext[T]()
Here is the autofac and signalr registration in global.asax service file
protected void Application_Start(object sender, EventArgs e)
{
RouteTable.Routes.MapHubs(new HubConfiguration { EnableCrossDomain = true });
var builder = new ContainerBuilder();
builder.RegisterType<Product_WCF_Service>().AsSelf();
builder.RegisterType<DbFactory>().As<IDbFactory>();
builder.RegisterType<UnitOfWork>().As<IUnitOfWork>();
builder.RegisterAssemblyTypes(
new[] {
typeof(ProductService).Assembly
})
.Where(t => t.Name.EndsWith("Service"))
.AsImplementedInterfaces();
builder.RegisterAssemblyTypes(
new[] {
typeof(ProductRepository).Assembly
})
.Where(t => t.Name.EndsWith("Repository"))
.AsImplementedInterfaces();
builder.RegisterType<ProductHub>().ExternallyOwned();
var container = builder.Build();
container.Resolve<IUnitOfWork>();
container.Resolve<IDbFactory>();
GlobalHost.DependencyResolver = new AutofacDependencyResolver(container);
AutofacHostFactory.Container = container;
AutoMapperConfiguration.Configure();
}
My service implementation
public class Product_WCF_Service : IProduct_WCF_Service
{
IUnitOfWork UnitOfWork;
IProductService ProductService;
public Product_WCF_Service(IUnitOfWork unitOfWork, IProductService productService)
{
this.ProductService = productService;
this.UnitOfWork = unitOfWork;
}
}
And my NUnit test which causes the exception to be thrown
[TestFixture]
public class WCF_Product_Service_Tests
{
private Mock<IProduct_WCF_Service> ProductWCFService;
private Mock<IUnitOfWork> UnitOfWork;
private Mock<IProductService> ProductService;
public WCF_Product_Service_Tests()
{
this.ProductWCFService = new Mock<IProduct_WCF_Service>();
this.UnitOfWork = new Mock<IUnitOfWork>();
this.ProductService = new Mock<IProductService>();
}
[Test]
public void RetreiveDataFromWCF_Service()
{
byte commitStatus = 1;
string response = string.Empty;
var service = new Product_WCF_Service(this.UnitOfWork.Object, this.ProductService.Object);
service.CreateProduct("", out response, out commitStatus);
}}
It's driving me crazy as i cannot test my service at all!

Answer 1

OK I searched around and finally i found a solution. I' leave it here just in case someone finds this useful
when registering autofac i enabled the property injection
var signalRConfig = new HubConfiguration();
var builder = new ContainerBuilder();
builder.RegisterType<ServiceHub>().ExternallyOwned(); // SignalR hub registration
builder.Register(i => signalRConfig.Resolver.Resolve<IConnectionManager>().GetHubContext<ServiceHub>()).ExternallyOwned();
builder.RegisterType<Product_WCF_Service>().AsSelf();
builder.RegisterType<DbFactory>().As<IDbFactory>().InstancePerLifetimeScope();
builder.RegisterType<UnitOfWork>().As<IUnitOfWork>().InstancePerLifetimeScope();
builder.RegisterAssemblyTypes(
new[] {
typeof(ProductService).Assembly
})
.Where(t => t.Name.EndsWith("Service"))
.AsImplementedInterfaces();
builder.RegisterAssemblyTypes(
new[] {
typeof(ProductRepository).Assembly
})
.Where(t => t.Name.EndsWith("Repository"))
.AsImplementedInterfaces();
builder.RegisterType<Product_WCF_Service>()
.PropertiesAutowired();
var container = builder.Build();
signalRConfig.Resolver = new Autofac.Integration.SignalR.AutofacDependencyResolver(container);
signalRConfig.EnableCrossDomain = true;
RouteTable.Routes.MapHubs(signalRConfig);
AutofacHostFactory.Container = container;
AutoMapperConfiguration.Configure();
In my service i added the hubcontext as a property in
public class Product_WCF_Service : IProduct_WCF_Service{
IUnitOfWork UnitOfWork;
IProductService ProductService;
public IHubContext InstanceHubContext { get; set; }
public Product_WCF_Service(IUnitOfWork unitOfWork, IProductService productService)
{
this.ProductService = productService;
this.UnitOfWork = unitOfWork;
}
and it worked as expected! I can now access the hubcontext as usual
this.InstanceHubContext.Clients.All.onNotSavedProduct(message);
Of course you will also need the Autofac.Integration.SignalR and Autofac.Integration.Wcf packages