With WebJobs 3.0, they propose to use the Dependency Injection via ConfigureServices()
However, the services added with AddScoped() are behaving the exact same way as AddSingleton(): they are configured for the lifetime of the WebJob. I would prefer to have it scoped per function call. How can we achieve this?
I tried to use my custom job activator and do something like this:
public T CreateInstance<T>()
{
using (var scope = _service.CreateScope())
{
var service = scope.ServiceProvider.GetService<T>();
return service;
}
}
However, this gives me the following error:
The operation cannot be completed because the DbContext has been disposed.
The initialization is disposed before any call is made. I can't find how to connect this scoping mechanism properly.
The goal is to do have scoped dependency per function. At the moment, this is the only work around found to fix this issue.
public async Task SendEmail(
[QueueTrigger("%AzureStorage:Queue:SendEmail%")] int emailId,
ILogger logger
)
{
// Ugly workaround that I have to insert in all my functions.
using (var scope = serviceProvider.CreateScope())
using (var myService = scope.ServiceProvider.GetService<IMyService>())
{
await myService.SendEmailAsync(emailId);
}
}
Related
Are objects that are referenced, not created, within a factory implementation disposed by the container? See code below:
services.AddTransient(c => OwinContext.ServiceObject);
Will ServiceObject, which implements IDisposable, be disposed by the container considering it isn't created (i.e. new ServiceObject)?
ServiceObject is currently registered as Scoped, but we are getting ObjectDisposedException on the rare occasion. I'm guessing it's getting disposed within OWIN sometimes before our services are able to use it, which is why I was hoping of making it Transient but I'm worried the container will dispose of it more frequently.
Disposable transient registrations are tracked by the container and disposed when their scope ends.
The Microsoft documentation is not always clear about this, as this documentation seems to suggest that "The framework does not dispose of the services automatically" that are "not created by the service container." Although the documentation is not incorrect, as it primarily talks about the registration of instances through the AddSingleton<T>(T instance) extension method — it is misleading because it doesn't hold for:
AddSingleton<T>(Func<IServiceProvider, T>),
AddScoped<T>(Func<IServiceProvider, T>), and
AddTransient<T>(Func<IServiceProvider, T>).
This statement can be easily verified using the following program:
using Microsoft.Extensions.DependencyInjection;
var disposable = new FakeDisposable();
var services = new ServiceCollection();
services.AddTransient(c => disposable);
var provider = services.BuildServiceProvider(validateScopes: true);
using (var scope = provider.CreateScope())
{
scope.ServiceProvider.GetRequiredService<FakeDisposable>();
}
public class FakeDisposable : IDisposable
{
public void Dispose() => Console.WriteLine("Disposed");
}
Output:
Disposed
Conclusion: Yes, transient registrations for disposable objects are disposed of by the container.
There will be little difference between making this registration Transient or Scoped. In both cases the object will get disposed when the scope ends.
In the case of a Transient registration, though, you'll start to see the disposable get disposed of multiple times in case it gets injected multiple times. For instance:
using (var scope = provider.CreateScope())
{
scope.ServiceProvider.GetRequiredService<FakeDisposable>();
scope.ServiceProvider.GetRequiredService<FakeDisposable>();
scope.ServiceProvider.GetRequiredService<FakeDisposable>();
}
Output:
Disposed
Disposed
Disposed
From reliability, however, it's better to stick with a Scoped registration, instead of Transient. This is because MS.DI will prevent Scoped registrations from being injected into Singleton consumers (in case the Service Provider is created by calling BuildServiceProvider(validateScopes: true)). In case your ServiceContext would get injected into a Singleton, it causes it to become a Captive Dependency and keep referenced (and likely used) by that Singleton, long after it got disposed of.
The most likely reason you are getting those ObjectDisposedExceptions is because Owin tries to use the ServiceContext after your (web request) scope is disposed.
The ServiceContext object is likely being controlled and disposed of by OWIN, which doesn't make it a good candidate to be disposed of by the container. But here's the problem: MS.DI will always try to dispose of Transient and Scoped registrations and the only way to prevent this from happening is to not register your ServiceContext.
The solution, therefore, is to wrap it in a "provider" object of some sort. For instance:
// New abstraction
public interface IServiceObjectProvider
{
object ServiceObject { get; }
}
// Implementation part of your Composition Root (see: https://mng.bz/K1qZ)
public class AmbientOwinServiceObjectProvider : IServiceObjectProvider
{
public object ServiceObject => OwinContext.ServiceObject;
}
// Registration:
services.AddScoped<IServiceObjectProvider, AmbientOwinServiceObjectProvider>();
// Usage:
public class MyController : Controller
{
private readonly IServiceObjectProvider provider;
public MyController(IServiceObjectProvider provider)
{
// Only store the dependency here: don't use it,
// see: https://blog.ploeh.dk/2011/03/03/InjectionConstructorsshouldbesimple/
this.provider = provider;
}
public string Index()
{
var so = this.provider.ServiceObject;
// Do something with the Service object
}
}
I use Unity in an MVC5 project (.net461) for DI and I want to register a service with multiple lifetimes.
With the classic core DI I would use RegisterScoped and that's it. Whenever the service is resolved within an Http Request I would reuse the same instance for the duration of the request. If I want to fire a background task, that background task should open a service scope, and I would resolve a new instance for the service for the duration of that scope. No need to have different registrations for the service. In the first case, the scope is created by the runtime, and in the second it is manually created by the developer. In both cases, the service provider only knows that the service is scoped, it doesn't care about where and how the scope has opened.
With Unity the first case is solved with PerRequestLifetimeManager. The second case is solved with a HierarchicalLifetimeManager.
But how should I have a combination of the two?
Whenever a service is resolved within an HttpRequest (in a controller constructor for instace) it should use the PerRequestLifetimeManager and wherever it is resolved in a child container (within the constructor of another service that is instantiated in the child container) it should use HierarchicalLifetimeManager.
How can I register the service with both managers?
At the end of the day, I had to implement my own solution which is based on (but not using) Unity.Mvc, Unity.WebApi packages, and the HierarchicalLifetimeManager.
None of the solutions I found online worked for my case. Most of them covered only the per request part, but not the per custom user scope part.
The key of the solution is not the lifetime manager but the dependency resolver. The lifetime manager for my requirements should always be HierarchicalLifetimeManager because that is what I truly need. A new container for each scope, which is covered by child containers and HierarchicalLifetimeManager.
Using Integrating ASP.NET Core Dependency Injection in MVC 4 as an example on how to implement your own dependency resolver, I came up with the solution below.
What I had to do, is to make sure a new scope is created on the beginning of the Http Request, and Disposed at the end of the Http Request. This part is covered by implementing a simple HttpModule. This part is similar to the HttpModule used by the official Unity Per Request Lifetime implementation.
Per Http Request Module
This is the module implementation
internal class UnityPerHttpRequestModule : IHttpModule
{
private static IUnityContainer _rootContainer;
public void Init(HttpApplication context)
{
context.BeginRequest += (s, e) =>
((HttpApplication)s).Context.Items[typeof(UnityPerHttpRequestModule)]
= _rootContainer.CreateChildContainer();
context.EndRequest += (s, e) =>
(((HttpApplication)s).Context.Items[typeof(UnityPerHttpRequestModule)]
as IUnityContainer)?.Dispose();
}
public static void SetRootContainer(IUnityContainer rootContainer)
{
_rootContainer = rootContainer ?? throw new ArgumentNullException(nameof(rootContainer));
}
public void Dispose() { }
}
On Beginning the request we create a new child container and place it in the HttpRequest Items dictionary.
On Ending the request we retrieve the child container from the Items dictionary and dispose it.
The static method SetRootContainer should be called once at the startup of the application to pass in the initial root Unity container, the one that services are registered on.
public class Global : HttpApplication
{
void Application_Start(object sender, EventArgs e)
{
UnityPerHttpRequestModule.SetRootContainer(UnityConfig.Container); // pass here the root container instance
...
}
}
We also need to register the module with owin.
using Microsoft.Owin;
using Microsoft.Web.Infrastructure.DynamicModuleHelper;
using Owin;
[assembly: OwinStartup(typeof(MyApp.Startup))]
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(MyApp.Startup), nameof(MyApp.Startup.InitScopedServicesModule))]
namespace MyApp
{
public partial class Startup
{
public static void InitScopedServicesModule()
{
DynamicModuleUtility.RegisterModule(typeof(UnityPerHttpRequestModule));
}
public void Configuration(IAppBuilder app)
{
}
}
}
MVC Dependency Resolver
Now the http module is registered and we have a new scope created on each request. Now we need to instruct MVC and WebApi to use that scope. For this, we need to create the appropriate dependency resolvers. I created one dependency resolver for MVC and one for WebApi since they need to implement different interfaces (I could have implemented both in the same class though).
The dependency resolver for MVC is this:
internal class UnityMvcPerHttpRequestDependencyResolver : IDependencyResolver
{
private readonly IUnityContainer rootContainer;
internal UnityMvcPerHttpRequestDependencyResolver(IUnityContainer rootContainer)
{
this.rootContainer = rootContainer;
}
internal IUnityContainer Current => (HttpContext.Current?.Items[typeof(UnityPerHttpRequestModule)] as IUnityContainer) ?? this.rootContainer;
public void Dispose() { }
public object GetService(Type serviceType)
{
try
{
return Current.Resolve(serviceType);
}
catch (ResolutionFailedException)
{
return null;
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
return Current.ResolveAll(serviceType);
}
catch (ResolutionFailedException)
{
return null;
}
}
}
What the resolver does is that it checks for an HTTP Context and gets the unity container in the Context's item dictionary and uses this container to resolve the services. So effectively, if the service requested is registered with a Hierarchical Lifetime, a new instance of that service will be created within the child container (aka within the context of the request). Since the child container is disposed at the end of the request by the http module, any services instantiated in the child container are also disposed.
Things to notice here:
The IDependencyResolver interface here is the System.Web.Mvc.IDependencyResolver. This is the interface expected by the MVC. The WebApi expects a difference IDependencyResolver (same name, different namespaces)
Catching ResolutionFailedException. If you don't catch those exceptions, the application will crash.
Now that we have the MVC dependecy resolver, we need to instruct MVC to use this resolver.
public static class UnityMvcActivator
{
public static void Start()
{
FilterProviders.Providers.Remove(FilterProviders.Providers.OfType<FilterAttributeFilterProvider>().First());
FilterProviders.Providers.Add(new UnityFilterAttributeFilterProvider(UnityConfig.Container));
//DependencyResolver.SetResolver(new UnityDependencyResolver(UnityConfig.Container));
DependencyResolver.SetResolver(new UnityMvcPerHttpRequestDependencyResolver(UnityConfig.Container));
// TODO: Uncomment if you want to use PerRequestLifetimeManager
//Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility.RegisterModule(typeof(UnityPerRequestHttpModule));
}
}
Things to notice here:
Do not register the official UnityPerRequestHttpModule since we implement our own. ( I could probably use that module but my implementation would depend on the inner implementation of the official module and I don't want that, since it may change later)
Web Api Dependency Resolver
Simlilar to MVC dependency resolver, we need to implement one for the Web Api
internal class UnityWebApiPerHttpRequestDependencyResolver : IDependencyResolver
{
private readonly IUnityContainer rootContainer;
internal UnityWebApiPerHttpRequestDependencyResolver(IUnityContainer rootContainer)
{
this.rootContainer = rootContainer;
}
internal IUnityContainer Current => (HttpContext.Current?.Items[typeof(UnityPerHttpRequestModule)] as IUnityContainer) ?? this.rootContainer;
public IDependencyScope BeginScope() => this;
// Dispose, GetService and GetServices are the same as MVC dependency resolver
}
Things to notice here:
IDependencyResolver here is of type System.Web.Http.Dependencies.IDependencyResolver. It is not the same as MVC's IDependencyResolver.
This Dependency resolver interface implements one more method: BeginScope. This is important here. WebApi pipeline is different that MVC pipeline. WebApi engine, by default, calls BeginScope to open a new scope for each web api request, and uses that scope to resolve controllers and services. So, Web api has already a scoped mechanism. BUT we have already created a scope ourselves with our per request module and we want to use that scope. So what we have to do here is to not create a new scope again. It already exists. So calling BeginScope on our resolver should return the same resolver scope, thus we return this.
Now that we have created the WebApi resolver, we have to also register it to web api.
using System.Web.Http;
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(MyApp.UnityWebApiActivator), nameof(MyApp.UnityWebApiActivator.Start))]
namespace MyApp
{
/// <summary>
/// Provides the bootstrapping for integrating Unity with WebApi when it is hosted in ASP.NET.
/// </summary>
public static class UnityWebApiActivator
{
/// <summary>
/// Integrates Unity when the application starts.
/// </summary>
public static void Start()
{
// Use UnityHierarchicalDependencyResolver if you want to use
// a new child container for each IHttpController resolution.
// var resolver = new UnityHierarchicalDependencyResolver(UnityConfig.Container);
var resolver = new UnityWebApiPerHttpRequestDependencyResolver(UnityConfig.Container);
GlobalConfiguration.Configuration.DependencyResolver = resolver;
}
}
}
Registering services
Now that we have set up and registered all our Resolvers and modules, the last thing to do is to remember to register each scoped service with HierarchicalLifetimeManager. Since our scoped solution depends on child containers, registering our scoped services that way will suffice.
Conclusion
And with that, I managed to implement a working scoped DI solution with Unity. The example below did not work with the official Per Request Lifetime solution, but worked with my custom implementation.
class TestController{
private readonly IMyScopedService service;
private readonly IUnityContainer container;
public TestController(IUnityContainer container, IMyScopedService service){
this.service = service;
this.container = container;
}
public ActionResult Post( ... ){
var childContainer = this.container.CreateChildContainer();
var scopedService = childContainer.GetService<IMyScopedService>()
HostingEnviroment.QueueBackgroundWorkItem(() => {
using(childContainer){
scopedService.DoWork();
}
});
}
}
With the official PerRequestLifetimeManager solution, this.service and scopedService were the same instance. The scoped service was instantiated in the http context, then the same instance was fetched again from the child container (since it was registerd with PerRequestLifetimeManager and not HierarchicalLifetimeManager) and passed to the background Job. The background job outlives the http request. The instance is disposed when the Http requests ends, but it is still being used in the background job which probably runs in another thread. Concurrency issues (and more) arise. For instance you can't use the same instance of an EF DbContext in multiple threads.
With the custom implementation above, the example works. scopedService is a different instance since it is registered with a HierarchicalLifetimeManager. this.services is disposed when the http request ends but scopedService lives during the whole execution of the background Job.
What we effectively do is control the lifetime of the services by controlling the lifetime of child containers. And I have the impression that this is the solution for every scoped service scenario.
Register all scoped services with HierarchicalLifetimeManager
Control the lifetime of services by controlling the lifetime of the child containers.
I am very new with orleans and trying to grasp everything with grains and so forth.
What i got is that in my startup.cs file i add the SignalR like this
public IServiceProvider ConfigureServices(IServiceCollection services)
{
Program.WriteConsole("Adding singletons");
services
.AddSingleton(achievementManager)
.AddMvc();
services.AddSingleton(SignalRClient);
return services.BuildServiceProvider();
}
So far everything is fine i can start my host/application and it connects to SignalR as it should. But what i cant wrap my head around is how do i get this down to my grain? if i had a controller i would simply send it down in the constructor on startup but how do i do this with a grain? Or can i even do it like this. Any guidance is appreciated.
In the grain then i want to do something like this
[StatelessWorker]
[Reentrant]
public class NotifierGrain : Grain, INotifierGrain
{
private HubConnection SignalRClient { get; }
public NotifierGrain(HubConnection signalRClient)
{
SignalRClient = signalRClient;
SignalRClient.SendAsync(Methods.RegisterService, Constants.ServiceName);
}
public Task NotifyClients(object message, MessageType type)
{
var registerUserNotification = (RegisterUserNotificationModel)message;
SignalRClient.SendAsync(Methods.RegisterUserToMultipleGroups, registerUserNotification.UserId, registerUserNotification.InfoIds);
}
return Task.CompletedTask;
}
Then i try to call the Notify method from another grain like this
var notifier = GrainFactory.GetGrain<INotifierGrain>(Constants.NotifierGrain);
await notifier.NotifyClients(notification, MessageType.RegisterUser);
But trying to do this ends up with an error like this
InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.SignalR.Client.HubConnection' while attempting to activate 'User.Implementation.Grains.NotifierGrain'.
Orleans supports constructor injection, so you can inject the SignalRClient into your grain constructor. In your code you are already correctly registering the client using services.AddSingleton(SignalRClient), so I will focus on how to inject the type into your grain.
I do not know what the type the SignalR client object is, but in this example I assume that the type is "SignalRClient":
[StatelessWorker]
[Reentrant]
public class NotifierGrain : Grain, INotifierGrain
{
private readonly SignalRClient signalRClient;
public NotifierGrain(SignalRClient signalRClient)
{
this.signalRClient = signalRClient;
}
public async Task NotifyClients(object message, MessageType type)
{
var registerUserNotification = (RegisterUserNotificationModel)message;
await this.signalRClient.SendAsync(
MessageMethods.RegisterUserToMultipleGroups,
registerUserNotification.UserId,
registerUserNotification.infoIds);
}
}
Depends how you're thinking to use SignalR Server, if you're going to host your SignalR server with Microsoft Orleans for sure you need to have backplane to handle the Orleans cluster communications.
You can use SignalR Orleans which has everything done out of the box for you :)
Also if you need a reactive SignalR library for the frontend, you can use Sketch7 SignalR Client
PS I m one of the authors of both libraries.
I would like to use ASP.NET Core's default DI container to setup DI for my Service Fabric project.
//This is what I've got so far, and it works great
ServiceRuntime.RegisterServiceAsync(
"MyServiceType",
context => new MyService(context, new MyMonitor()
).GetAwaiter().GetResult();
//This is how I use it
public MyService(StatefulServiceContext context, IMonitor myMonitor)
: base(context)
{
this._myMonitor = myMonitor;
}
How would I set up DI, if MyMonitor class has a dependency on a ConfigProvider class, like this:
public MyMonitor(IConfigProvider configProvider)
{
this._configProvider = configProvider;
}
I think this question will give you some light: Why does ServiceRuntime.RegisterServiceAsync return before the serviceFactory func completes?
Technically, the ServiceRuntime.RegisterServiceAsync() is a dependency registration, it requires you to pass the serviceTypeName and the factory method responsible for creating the services Func<StatelessServiceContext, StatelessService> serviceFactory
The factory method receives the context and returns a service (Stateful or stateless).
For DI, you should register all dependencies in advance and call resolve services to create the constructor, something like:
var provider = new ServiceCollection()
.AddLogging()
.AddSingleton<IFooService, FooService>()
.AddSingleton<IMonitor, MyMonitor>()
.BuildServiceProvider();
ServiceRuntime.RegisterServiceAsync("MyServiceType",
context => new MyService(context, provider.GetService<IMonitor>());
}).GetAwaiter().GetResult();
PS:
Never Register the context (StatelessServiceContext\StatefulServiceContext) in the DI, in a shared process approach, multiple partitions might be hosted on same process and will have multiple contexts.
This code snippet is not tested, I've used in the past, don't have access to validate if matches the same code, but is very close to the approach used, might need some tweaks.
Hi #OscarCabreraRodrÃguez
I am working on the project that simplifies development of Service Fabric Reliable Services and it has great built-in support for dependency injection scenarios.
You can find general information project page, wiki and specific information about dependency injection here.
The idea is that project abstracts you from working with Service instance directly instead providing you with a set of more concrete objects.
Here is a simple example for ASP.NET Core application:
public static void Main(string[] args)
{
new HostBuilder()
.DefineStatefulService(
serviceBuilder =>
{
serviceBuilder
.UseServiceType("ServiceType")
.DefineAspNetCoreListener(
listenerBuilder =>
{
listenerBuilder
.UseEndpoint("ServiceEndpoint")
.UseUniqueServiceUrlIntegration()
.ConfigureWebHost(
webHostBuilder =>
{
webHostBuilder
.ConfigureServices(
services =>
{
// You can configure as usual.
services.AddTransient<IMyService, MyService>();
})
.UseStartup<Startup>();
});
});
})
.Build()
.Run();
[Route("api")]
public class ApiController : Controller
{
public ApiController(IMyService service) { }
[HttpGet]
[Route("value")]
public string GetValue()
{
return $"Value from {nameof(ApiController)}";
}
}
Hope I understand your use case correctly and this information is relevant.
I've set up a Web API project using Ninject, and I've used the fix detailed here for getting it to work with the latest version of the Web API. Everything is working fine, but I'm now trying to write some tests.
I'm using in-memory hosting to run the project for the tests, as detailed here, as I have a DelegatingHandler that performs authentication and then sets a property on the request message that is used by all the Api Controllers.
So, I've got a base class for my tests, and have a SetUp method where I set up the HttpServer and configuration, which I've pretty much taken from my working Ninject code:
[SetUp]
public void Setup()
{
bootstrapper = new Bootstrapper();
DynamicModuleUtility.RegisterModule(
typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(
typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
var config = new HttpConfiguration();
config.Routes.MapHttpRoute("Login",
"api/auth/token",
new { controller = "Users", action = "Login" });
config.IncludeErrorDetailPolicy =
IncludeErrorDetailPolicy.Always;
config.DependencyResolver =
new NinjectResolver(CreateKernel());
config.MessageHandlers.Add(
new AuthenticationHandler(CreateUserManager()));
Server = new HttpServer(config);
}
This is how I create the MoqMockingKernel:
private static IKernel CreateKernel()
{
var kernel = new MoqMockingKernel();
kernel.Bind<Func<IKernel>>()
.ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>()
.To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
GlobalConfiguration.Configuration.DependencyResolver =
new NinjectResolver(kernel);
return kernel;
}
And this is how I register the objects to use:
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IUserManager>().ToMock();
kernel.Bind<UsersController>().ToSelf();
}
While I'm not testing the Controller per se, I do want a proper instance of it to be called, which is why I'm binding it ToSelf. I must admit that I am assuming that this is correct. This is an example of a test:
public void UserCannotLogin()
{
System.Net.Http.HttpClient client =
new System.Net.Http.HttpClient(Server);
string json = string.Format(
"{{ \"Username\": \"{0}\", \"Password\": \"{1}\" }}",
"wrong", "wrong");
HttpRequestMessage request =
CreateRequest(#"api/auth/token", json, HttpMethod.Get);
Action action = () => client.SendAsync(request);
using (var response = client.SendAsync(request).Result)
{
response.StatusCode.Should()
.Be(HttpStatusCode.Unauthorized);
}
}
I'm basically getting a 404 error. When I debug it, it does go to my DelegatingHandler, but it doesn't go to my controller.
I get the feeling that I'm fundamentally missing a point here, and it may not even be possible to do what I'm trying to do, but if anyone has any suggestions for either how to do this, or a different way to achieve the same thing, I'm all ears.
Update I think that it's because the default behaviour of the MockingKernel is to provide a Mock unless told otherwise, so it is returning a Mock of IHttpControllerSelector. I've set up a couple of default ones now:
kernel.Bind<IHttpControllerSelector>()
.To<DefaultHttpControllerSelector>();
kernel.Bind<IContentNegotiator>()
.To<DefaultContentNegotiator>();
It's still not working, I think because there are no formatters specified. I'll try that tomorrow and see if that gets me there.
Ok, I think that I was correct when I said that I was fundamentally missing a point here, but I'll answer this in case it helps someone else avoid the same mistake!
The Ninject MockingKernel is, I think, primarily about auto-mocking, so where you have a lot of interfaces you don't care about how they are set up in your test, you can ignore them in your tests and they will be automatically created for you.
In the case of the Web API, this is most definitely not the case, as you don't want the controller selector class to be auto mocked, otherwise you won't end up calling your controllers.
So, the solution I've come up with is to stick with using a standard Ninject Kernel, and then bind your interface to a constant Mock object:
kernel.Bind<IUserManager>().ToConstant(CreateUserManager());
private IUserManager CreateUserManager()
{
Mock<IUserManager> userManager = new Mock<IUserManager>();
// Set up the methods you want mocked
return userManager.Object;
}
Doing this, I've been able to successfully write tests that use an HttpClient to call an in-memory HttpServer that successfully call my DelegatingHandler and then end up at my controllers.