IOC injection of IServerSideEvents

问题:

I am writing unit tests for my IOC. One of my interfaces injects IServerEvents.

I am including events via:

  ServerEventsFeature serverEventsFeature = new ServerEventsFeature()
            {
                LimitToAuthenticatedUsers = false,
                NotifyChannelOfSubscriptions = false,
                OnConnect = (eventSubscription, dictionary) =>
                {
                },
                OnSubscribe = (eventSubscription) =>
                {
                }
            };

However, container.Resolve gives the following error when debugging (Not through unit tests) :

'container.Resolve<IServerEvents>()' threw an exception of type 'System.Exception'
    Data: {System.Collections.ListDictionaryInternal}
    HResult: -2146233088
    HelpLink: null
    InnerException: {System.InvalidOperationException: No service for type 'ServiceStack.IServerEvents' has been registered.
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
   at Funq.Container.ResolveImpl[TService](String name, Boolean throwIfMissing)}
    Message: "Error trying to resolve Service 'ServiceStack.IServerEvents' or one of its autowired dependencies (see inner exception for details)."
    Source: "ServiceStack"
    StackTrace: "   at Funq.Container.ResolveImpl[TService](String name, Boolean throwIfMissing)"
    TargetSite: {TService ResolveImpl[TService](System.String, Boolean)}

This does work in normal usage, but manual Resolve of the interface does not work.

What I am wondering is :

A) proper way to unit test this integration of server events

B) Should I merely mock the IServerEvents on the container with a RegisterAs<>() in unit tests

C) Why the injection works fine but container.Resolve() fails.

Any feedback is appreciated.

回答1:

You can't use ServerEventsFeature in a unit test, you'll only be able to make use of it in an integration test. You can find some working examples in ServerEventTests.

As ServerEventsFeature is a plugin, it needs to be registered as a plugin to function:

Plugins.Add(new ServerEventsFeature { ... });

Which when the plugin is registered will register the MemoryServerEvents dependency:

container.Register<IServerEvents>(memoryServerEvents);