I am having problems getting NServiceBus 4.6.1 dependency injection working with Saga timeouts. I am using self-hosting in an ASP.NET web application and have property injection setup. It works when messages are sent from web controllers however, when a Timeout message is handled in the saga the same DI property is not being set and is null.
Here are the key bits of the setup:
Global.asax.cs
public class MvcApplication : System.Web.HttpApplication
{
public static IWindsorContainer Container { get; private set; }
protected void Application_Start()
{
ConfigureIoC();
AreaRegistration.RegisterAllAreas();
GlobalConfiguration.Configure(WebApiConfig.Register);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
DeviceManagerDbInitializer.Instance.InitializeDatabase();
ConfigureNServiceBus();
}
protected void Application_End()
{
if (Container != null)
{
Container.Dispose();
}
}
private static void ConfigureIoC()
{
Container = new WindsorContainer()
.Install(FromAssembly.This());
var controllerFactory = new WindsorControllerFactory(Container.Kernel);
ControllerBuilder.Current.SetControllerFactory(controllerFactory);
GlobalConfiguration.Configuration.DependencyResolver
= new WindsorDependencyResolver(Container);
}
private void ConfigureNServiceBus()
{
Configure.ScaleOut(s => s.UseSingleBrokerQueue());
Configure.Instance.PeekInterval(500);
Configure.Instance.MaximumWaitTimeWhenIdle(2000);
Feature.Enable<TimeoutManager>();
Feature.Enable<Sagas>();
IStartableBus startableBus = Configure.With()
.DefineEndpointName("MyQueue")
.CastleWindsorBuilder(Container) //using NServiceBus CastleWindsor 4.6.1
.UseTransport<AzureStorageQueue>()
.UseAzureTimeoutPersister()
.AzureSagaPersister()
.PurgeOnStartup(false)
.UnicastBus()
.LoadMessageHandlers()
.RunHandlersUnderIncomingPrincipal(false)
.Log4Net(new DebugAppender { Threshold = Level.Warn })
.RijndaelEncryptionService()
.CreateBus();
Configure.Instance.ForInstallationOn<Windows>().Install();
startableBus.Start();
}
}
Saga class
public class MySaga: Saga<MySagaData>,
IAmStartedByMessages<StartMySagaCommand>,
IHandleMessages<SomeMessage>,
IHandleTimeouts<SomeTimeout>
{
public DependentService MyInjectedService {get; set;}
public override void ConfigureHowToFindSaga()
{
ConfigureMapping<StartMySagaCommand>( message => message.MyId).ToSaga( saga => saga.MyId );
ConfigureMapping<SomeMessage>( message => message.MyId).ToSaga( saga => saga.MyId );
ConfigureMapping<SomeTimeout>( message => message.MyId).ToSaga( saga => saga.MyId );
}
public void Handle(SomeMessage message)
{
// Here MyInjectedService is fine
MyInjectedService.DoSomething(message);
}
public void Timeout(SomeTimeout state)
{
// Here MyInjectedService is always null
MyInjectedService.DoSomething(state);
}
}
I have tried solutions found here, here and here but none of them fixed the issue.
I figured out the problem here. Dependency injection was not working in the Saga's timeout handler because the Castle.Windsor lifestyle was set to LifestylePerWebRequest, e.g.:
public class WindsorServicesInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register( Component.For<DependentService>()
.LifestylePerWebRequest() );
}
}
After changing the Lifestyle to LifeStyleTransient it started working. Any of the other 'non web request' lifestyles should work as well here.
In our setup the NServiceBus host is running under the web application and the regular message handlers were fine because they are being called in a controller action, e.g.:
[HttpPost]
public ActionResult DoSomething( int myId)
{
_bus.Send( "MyBus", new SomeMessage { MyId = something.MyId } );
return View();
}
When the saga handles the SomeMessage message for this it must still be part of the web request and Windsor resolves the dependency as normal. However, the timeouts are fired some time later (in this case five minutes) are they are not part of a web request. Windsor is not able to resolve the DependentService object and it stays null.
Related
I'm currently working on an ASP.NET Core Web Application.
I have a MQTT Server, which is connected to a service (IHostedService) and this service references a SignalR Hub.
So if there is a new message comming from the MQTT Server, it is forwarded to the hub and therefore to the client.
This works fine. But now I would like to add a button to send MQTT messages back to the MQTT server.
To do so, I added a function in the hub, which es called by the button via SignalR.
So far so good but when adding the service now to the constructor of the hub it fails, when I open the web app (not during startup), with the following message:
fail: Microsoft.AspNetCore.SignalR.HubConnectionHandler[1]
Error when dispatching 'OnConnectedAsync' on hub.
System.InvalidOperationException: Unable to resolve service for type 'websiteApp.HostedServices.UserPromptService' while attempting to activate 'websiteApp.Hubs.UserPromptHub'.
at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, Boolean isDefaultParameterRequired)
at lambda_method(Closure , IServiceProvider , Object[] )
at Microsoft.AspNetCore.SignalR.Internal.DefaultHubActivator'1.Create()
at Microsoft.AspNetCore.SignalR.Internal.DefaultHubDispatcher'1.OnConnectedAsync(HubConnectionContext connection)
at Microsoft.AspNetCore.SignalR.Internal.DefaultHubDispatcher'1.OnConnectedAsync(HubConnectionContext connection)
at Microsoft.AspNetCore.SignalR.HubConnectionHandler'1.RunHubAsync(HubConnectionContext connection)
The service declaration looks like this:
public class UserPromptService : IHostedService, IDisposable
{
public UserPromptService(ILogger<UserPromptService> logger, IConfiguration config, UserPromptContext userPromptContext, IHubContext<UserPromptHub> userPromptHub)
{
}
}
And my hub looks like this:
public class UserPromptHub : Hub<IUserPromptHub>
{
public UserPromptHub(UserPromptService service) // everything works until I add the service here
{
service.ToString(); // just for testing
}
}
And they are configured in the Startup.cs:
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
// ...
app.UseEndpoints(endpoints =>
{
endpoints.MapRazorPages();
endpoints.MapHub<Hubs.UserPromptHub>("/userPromptHub");
});
}
As well as in the Program.cs:
public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
// ...
.ConfigureServices(services =>
{
services.AddSingleton<websiteApp.DataContext.UserPromptContext>();
services.AddHostedService<HostedServices.UserPromptService>();
});
Could you please help me to fix the problem?
One option to solve your problem would be to restructure your code a little bit.So instead of your UserPromptService be responsable for the MQTT connection you create a seperate class for that.
The following is only sudo code
You could create a new class
public class MQTTConnection
{
private readonly _yourMQTTServerConnection;
public MQTTConnection()
{
_yourMQTTServerConnection = new ServerConnection(connectionstring etc);
}
public Task<Message> GetMessage()
{
return _yourMQTTServerConnection.GetMessageAsync();
}
public Task SendMessage(Message message)
{
return _yourMQTTServerConnection.SendMessageAsync(message);
}
}
So your Hub look something like this
public class UserPromptHub : Hub<IUserPromptHub>
{
private readonly MQTTConnection _connection;
public UserPromptHub(MQTTConnection connection)
{
_connection = connection
}
public async Task MessageYouReceiveFromTheUser(object object)
{
// your business logic
await _connection.SendMessage(message);
}
public Task MessageYouSendToTheClient(object object)
{
await Clients.All.MessageYouSendToTheClient(message);
}
}
And your UserPromptService looks somehting like that
public class UserPromptService : IHostedService, IDisposable
{
public UserPromptService(ILogger<UserPromptService> logger,
IConfiguration config,
UserPromptContext userPromptContext,
IHubContext<UserPromptHub> userPromptHub,
MQTTConnection connection)
{
// map arguments to private fields
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
while(yourAppIsUpAndRunning)
{
var message = await _connection.GetMessage()
// process the message
await _hub.MessageYouSendToTheClient(yourMessage)
}
}
}
I hope my approach is understandable, if not I can add more details.
My main problem is to get the right instance of the SignalR hub.
Context: Im building a webapplication which communicates with a couple of external systems. CRUD operations in my application result in updating the databases of the external systems.
In this example i have 3 services running:
ExternalSystem | StateMachine | .NET CORE WebAPI
When i post the 'create employee' form, a RabbitMQ message will be sent from the WebAPI to the statemachine. The statemachine then sends a couple of create messages to my external system service which updates the database. Thereafter, it updates the statemachine to keep track of the createoperation.
Form -> API -> StateMachine -> ExternalSystem -> StateMachine -> API
So far so good. Now i would like to use SignalR to send the status updates to the client. So i've implemented this consumer in the API:
public class UpdatesConsumer :
IConsumer<IExternalSystemUpdateMessage>
{
private readonly IHubContext<UpdatesHub> _updaterHubContext;
public UpdatesConsumer(IHubContext<UpdatesHub> hubContext)
{
_updaterHubContext = hubContext;
}
public Task Consume(ConsumeContext<IExternalSystemUpdateMessage> context)
{
//return _updaterHubContext.Clients.Group(context.Message.CorrelationId.ToString()).SendAsync("SEND_UPDATE", context.Message.Message);// this.SendUpdate(context.Message.CorrelationId, context.Message.Message);
return _updaterHubContext.Clients.All.SendAsync("SEND_UPDATE", context.Message.Message);
}
}
This is my SignalR hub:
public class UpdatesHub :
Hub
{
public Task SendUpdate(Guid correlationId, string message)
{
return Clients.Group(correlationId.ToString()).SendAsync("SEND_UPDATE", message);
}
}
And this is how the Bus and consumer is instantiated:
public void ConfigureServices(IServiceCollection services)
{
_services = services;
services.AddMvc();
services.AddSignalR();
//services.AddSingleton<IHubContext<UpdatesHub>>();
WebAPI.CreateBus();
}
public static IServiceCollection _services;
static IBusControl _busControl;
public static IBusControl Bus
{
get
{
return _busControl;
}
}
public static void CreateBus()
{
IRMQConnection rmqSettings = Config.GetRMQConnectionConfig("rmq-settings.json", "connection");
_busControl = MassTransit.Bus.Factory.CreateUsingRabbitMq(x =>
{
var host = x.Host(BusInitializer.GetUri("", rmqSettings), h =>
{
h.Username(rmqSettings.UserName);
h.Password(rmqSettings.Password);
});
x.ReceiveEndpoint(host, "externalsystems.update",
e => { e.Consumer(() => new UpdatesConsumer((IHubContext<UpdatesHub>)Startup.__serviceProvider.GetService(typeof(IHubContext<UpdatesHub>)))); });
});
TaskUtil.Await(() => _busControl.StartAsync());
}
=========================================================================
So the problem is that _updaterHubContext.Clients in my Consumer class, always turn out to be empty. I've tested accessing the hub in a controller, and the clients do show up:
public class TestController : Controller
{
private readonly IHubContext<UpdatesHub> _hubContext;
public TestController(IHubContext<UpdatesHub> hubContext)
{
_hubContext = hubContext;
}
[HttpGet]
[Route("api/Test/")]
public IActionResult Index()
{
return View();
}
}
How can i get the right instance of the hub in my Consumer class? Or how can i access the IServiceCollection that .net is using?
Thnx in advance!
You can register your consumer so that MassTransit will resolve it from the IServiceProvider using the support provided in the MassTransit.Extensions.DependencyInjection package.
x.ReceiveEndpoint(host, "externalsystems.update", e =>
{
e.Consumer<UpdatesConsumer>(_serviceProvider);
});
Be sure to register your UpdatesConsumer in the container as well. This should resolve a new instance of the consumer for each message received on the endpoint.
Why not register Bus using Microsoft Dependency Injection. It should fix your issue, it will Resolve your consumer using IServiceProvider
I am using NServiceBus v4.3, MVC4, RavenDB 2.5 and StructureMap 2.6.4 in our solution.
I am having a similar issue under StructureMap to that described in this question's responses where I require different lifecycles for the MVC Controller and NServiceBus Handler use of RavenDB's IDocumentSession in my Web project.
Specifically in my case what happens is that if I use the HybridHttpOrThreadLocalScoped (as the above answer suggests for Windsor) lifecycle the sessions are not properly disposed of and I soon hit the 30 transaction limit error. If I use the HttpContext lifecycle my NSB event Handlers in the Web project do not get called.
In my Controllers the session is wrapped in a unit of work applied via an MVC ActionFilter. I also use the UoW within the Handlers as my Registry is wired up to retrieve the session from the UoW. The code is as such:
RavenDbWebRegistry.cs
public sealed class RavenDbWebRegistry : Registry
{
public RavenDbWebRegistry()
{
// register RavenDB document store
ForSingletonOf<IDocumentStore>().Use(() =>
{
var documentStore = new DocumentStore
{
ConnectionStringName = "RavenDB",
Conventions =
{
IdentityPartsSeparator = "-",
JsonContractResolver = new PrivatePropertySetterResolver(),
},
};
documentStore.Initialize();
return documentStore;
});
For<IDocumentSession>().HybridHttpOrThreadLocalScoped().Add(ctx =>
{
var uow = (IRavenDbUnitOfWork)ctx.GetInstance<IUnitOfWork>();
return uow.DocumentSession;
});
For<IUnitOfWork>().HybridHttpOrThreadLocalScoped().Use<WebRavenDbUnitOfWork>();
}
}
Example of Web project Handler:
public class SiteCreatedEventHandler : IHandleMessages<ISiteCreatedEvent>
{
public IBus Bus { get; set; }
public IUnitOfWork Uow { get; set; }
public IDocumentSession DocumentSession { get; set; }
public void Handle(ISiteCreatedEvent message)
{
try
{
Debug.Print(#"{0}{1}", message, Environment.NewLine);
Uow.Begin();
var site = DocumentSession.Load<Site>(message.SiteId);
Uow.Commit();
//invoke Hub and push update to screen
var context = GlobalHost.ConnectionManager.GetHubContext<AlarmAndNotifyHub>();
//TODO make sure this SignalR function is correct
context.Clients.All.displayNewSite(site, message.CommandId);
context.Clients.All.refreshSiteList();
}
catch (Exception ex)
{
Uow.Rollback();
}
}
}
Usage of ActionFilter:
[RavenDbUnitOfWork]
public ViewResult CreateNew(int? id)
{
if (!id.HasValue || id.Value <= 0)
return View(new SiteViewModel { Guid = Guid.NewGuid() });
var targetSiteVm = MapSiteToSiteViewModel(SiteList(false)).FirstOrDefault(s => s.SiteId == id.Value);
return View(targetSiteVm);
}
WebRegistry (that sets up NSB in my MVC project)
public sealed class WebRegistry : Registry
{
public WebRegistry()
{
Scan(x =>
{
x.TheCallingAssembly();
x.Assembly("IS.CommonLibrary.ApplicationServices");
x.LookForRegistries();
});
IncludeRegistry<RavenDbWebRegistry>();
FillAllPropertiesOfType<IUnitOfWork>();
FillAllPropertiesOfType<IDocumentSession>();
FillAllPropertiesOfType<StatusConversionService>();
FillAllPropertiesOfType<IStateRepository<TieState>>();
FillAllPropertiesOfType<IStateRepository<DedState>>();
FillAllPropertiesOfType<ITieService>();
FillAllPropertiesOfType<IDedService>();
FillAllPropertiesOfType<IHbwdService>();
//NServiceBus
ForSingletonOf<IBus>().Use(
NServiceBus.Configure.With()
.StructureMapBuilder()
.DefiningCommandsAs(t => t.Namespace != null && t.Namespace.EndsWith("Command"))
.DefiningEventsAs(t => t.Namespace != null && t.Namespace.EndsWith("Event"))
.DefiningMessagesAs(t => t.Namespace == "Messages")
.RavenPersistence("RavenDB")
.UseTransport<ActiveMQ>()
.DefineEndpointName("IS.Argus.Web")
.PurgeOnStartup(true)
.UnicastBus()
.CreateBus()
.Start(() => NServiceBus.Configure.Instance
.ForInstallationOn<Windows>()
.Install())
);
//Web
For<HttpContextBase>().Use(() => HttpContext.Current == null ? null : new HttpContextWrapper(HttpContext.Current));
For<ModelBinderMappingDictionary>().Use(GetModelBinders());
For<IModelBinderProvider>().Use<StructureMapModelBinderProvider>();
For<IFilterProvider>().Use<StructureMapFilterProvider>();
For<StatusConversionService>().Use<StatusConversionService>();
For<ITieService>().Use<TieService>();
For<IDedService>().Use<DedService>();
For<IHbwdService>().Use<HbwdService>();
For<ISiteService>().Use<SiteService>();
IncludeRegistry<RedisRegistry>();
}
I have tried configuring my Registry using every possible combination I can think of to no avail.
Given that the StructureMap hybrid lifecycle does not work as I would expect, what must I do to achieve the correct behaviour?
Is the UoW necessary/beneficial with RavenDB? I like it (having adapted it from my earlier NHibernate UoW ActionFilter) because of the way it manages the lifecycle of my sessions within Controller Actions, but am open to other approaches.
What I would ideally like is a way to - within the Web project - assign entirely different IDocumentSessions to Controllers and Handlers, but have been unable to work out any way to do so.
Firstly, RavenDB already implements unit of work by the wrapping IDocumentSession, so no need for it. Opening a session, calling SaveChanges() and disposing has completed the unit of work
Secondly, Sessions can be implemented in a few ways for controllers.
The general guidance is to set up the store in the Global.asax.cs. Since there is only 1 framework that implements IDocumentSession - RavenDB, you might as well instantiate it from the Global. If it was NHibernate or Entity Framework behind a repository, I'd understand. But IDocumentSession is RavenDB specific, so go with a direct initialization in the Application_Start.
public class Global : HttpApplication
{
public void Application_Start(object sender, EventArgs e)
{
// Usual MVC stuff
// This is your Registry equivalent, so insert it into your Registry file
ObjectFactory.Initialize(x=>
{
x.For<IDocumentStore>()
.Singleton()
.Use(new DocumentStore { /* params here */ }.Initialize());
}
public void Application_End(object sender, EventArgs e)
{
var store = ObjectFactory.GetInstance<IDocumentStore>();
if(store!=null)
store.Dispose();
}
}
In the Controllers, add a base class and then it can open and close the sessions for you. Again IDocumentSession is specific to RavenDB, so dependency injection doesn't actually help you here.
public abstract class ControllerBase : Controller
{
protected IDocumentSession Session { get; private set; }
protected override void OnActionExecuting(ActionExecutingContext context)
{
Session = ObjectFactory.GetInstance<IDocumentStore>().OpenSession();
}
protected override void OnActionExecuted(ActionExecutedContext context)
{
if(this.IsChildAction)
return;
if(content.Exception != null && Session != null)
using(context)
Session.SaveChanges();
}
}
Then from there, inherit from the base controller and do your work from there:
public class CustomerController : ControllerBase
{
public ActionResult Get(string id)
{
var customer = Session.Load<Customer>(id);
return View(customer);
}
public ActionResult Edit(Customer c)
{
Session.Store(c);
return RedirectToAction("Get", c.Id);
}
}
Finally, I can see you're using StructureMap, so it only takes a few basic calls to get the Session from the DI framework:
public class SiteCreatedEventHandler : IHandleMessages<ISiteCreatedEvent>
{
public IBus Bus { get; set; }
public IUnitOfWork Uow { get; set; }
public IDocumentSession DocumentSession { get; set; }
public SiteCreatedEventHandler()
{
this.DocumentSession = ObjectFactory.GetInstance<IDocumentStore>().OpenSession();
}
public void Handle(ISiteCreatedEvent message)
{
using(DocumentSession)
{
try
{
Debug.Print(#"{0}{1}", message, Environment.NewLine);
///// Uow.Begin(); // Not needed for Load<T>
var site = DocumentSession.Load<Site>(message.SiteId);
//// Uow.Commit(); // Not needed for Load<T>
// invoke Hub and push update to screen
var context = GlobalHost.ConnectionManager.GetHubContext<AlarmAndNotifyHub>();
// TODO make sure this SignalR function is correct
context.Clients.All.displayNewSite(site, message.CommandId);
context.Clients.All.refreshSiteList();
}
catch (Exception ex)
{
//// Uow.Rollback(); // Not needed for Load<T>
}
}
}
I have an ASP.NET MVC app with SignalR and WebAPI. The app uses Ninject for dependency injection, but apparently SignalR and WebAPI are getting different kernels, so it fails to share a singleton object that should be shared for all the application.
I can see clearly in the log how an instance is created when SignalR gets a connection request, and other when WebAPI gets a request.
I want to have the same Ninject kernel shared among these three elements, so I can have unique singletons.
This is what I have done so far:
The first thing I have done is creating a NinjectModule declaring the binding:
public class MyDependencyModule: NinjectModule
{
public override void Load()
{
var binding = Bind<MustBeSingleton>().ToSelf();
binding.OnActivation((ctx, o) =>
{
Debug.Print("Registering item " + o.GetHashCode());
HostingEnvironment.RegisterObject(o);
});
binding.OnDeactivation(o =>
{
Debug.Print("Unregistering game connection " + o.GetHashCode());
});
binding.InSingletonScope();
}
}
I have also created a wrapper for Ninject in order to plug it in WebAPI:
public class NinjectDependencyScope : IDependencyScope
{
private IResolutionRoot resolver;
internal NinjectDependencyScope(IResolutionRoot resolver)
{
this.resolver = resolver;
}
public void Dispose()
{
IDisposable disposable = resolver as IDisposable;
if (disposable != null)
disposable.Dispose();
resolver = null;
}
public object GetService(Type serviceType)
{
if (resolver == null)
throw new ObjectDisposedException("this", "This scope has already been disposed");
return resolver.TryGet(serviceType);
}
public IEnumerable<object> GetServices(Type serviceType)
{
if (resolver == null)
throw new ObjectDisposedException("this", "This scope has already been disposed");
return resolver.GetAll(serviceType);
}
}
public class NinjectDependencyResolver : NinjectDependencyScope, IDependencyResolver
{
private IKernel kernel;
public NinjectDependencyResolver(IKernel kernel)
: base(kernel)
{
this.kernel = kernel;
}
public IDependencyScope BeginScope()
{
return new NinjectDependencyScope(kernel.BeginBlock());
}
}
Also, I have created another wrapper for SignalR:
public class SignalRNinjectDependencyResolver : DefaultDependencyResolver
{
private readonly IKernel _kernel;
public SignalRNinjectDependencyResolver(IKernel kernel)
{
_kernel = kernel;
}
public override object GetService(Type serviceType)
{
return _kernel.TryGet(serviceType) ?? base.GetService(serviceType);
}
public override IEnumerable<object> GetServices(Type serviceType)
{
return _kernel.GetAll(serviceType).Concat(base.GetServices(serviceType));
}
}
Then I have created a Ninject kernel that does all the config:
public class ApplicationDependencies:StandardKernel
{
public ApplicationDependencies()
:base(new MyDependencyModule())
{
System.Web.Http.GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(this);
Microsoft.AspNet.SignalR.GlobalHost.DependencyResolver = new SignalRNinjectDependencyResolver(this);
}
}
The MVC application, uses NinjectHttpApplication as base class, so I indicate the kernel that must be used this way:
public class MvcApplication : Ninject.Web.Common.NinjectHttpApplication
{
protected override Ninject.IKernel CreateKernel()
{
return new ApplicationDependencies();
}
}
Also, in the SignalR configuration I specify the Resolver:
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.MapSignalR<MyPersistentConnection>("/updates", new ConnectionConfiguration()
{
Resolver = GlobalHost.DependencyResolver
});
}
}
(I have tried also without specifying the resolver, and it does not work either).
Any idea?
Cheers.
I found the answer in another post: Singleton Scope binding not working as intended
Rather than binding as a singleton, "ToConstant" must be used:
var binding = Bind<MustBeSingleton>().ToConstant(new MustBeSingleton());
I have created a simple demo project with ASP.NET MVC, WebAPI and SignalR using the same dependency injection context.
https://drive.google.com/file/d/0B52OsuSSsroNX0I5aWFFb1VrRm8/edit?usp=sharing
The web app, contains a single page that shows the AppDomain and GetHashCode of an object that is supposed to be unique across the three frameworks, giving a result similar to:
Dependency Test
Framework IMySingletonService instance
MVC AppDomainId:2 / HashCode:5109846
WebAPI AppDomainId:2 / HashCode:5109846
SignalR AppDomainId:2 / HashCode:5109846
Other problem was, that Ninject was disposing my singleton because was IDisposable. I don't really understand why this happens, but that is another war.
Cheers.
In order keep this 3 things working.. you should check these references out:
Web API + Ninject
http://www.peterprovost.org/blog/2012/06/19/adding-ninject-to-web-api/
SignalR + Ninject https://github.com/SignalR/SignalR/wiki/Extensibility (last part:
When using ASP.NET MVC, configure SignalR first, then ASP.NET MVC)
For the second one, I refactored a little bit, since I need the kernel for SignalR Dependency Resolver
// Route SignalR.
GlobalHost.DependencyResolver = NinjectWebCommon.GetSignalrResolver();
RouteTable.Routes.MapHubs();
I defined GetSignalrResolver inside of NinjectWebCommon like this:
public static Microsoft.AspNet.SignalR.Ninject.NinjectDependencyResolver GetSignalrResolver()
{
return new Microsoft.AspNet.SignalR.Ninject.NinjectDependencyResolver(bootstrapper.Kernel);
}
Note: There are 2 different DependencyResolver: one for Web API (1) assigned to GlobalConfiguration.Configuration.DependencyResolver and the other for SignalR (2) assigned to GlobalHost.DependencyResolver
in order to use a dependency resolver for both WebApi and SignalR you need to implement a class that looks like this:
public class NinjectDependencyResolver : Microsoft.AspNet.SignalR.DefaultDependencyResolver,
System.Web.Http.Dependencies.IDependencyResolver
{
public readonly IKernel Kernel;
public NinjectDependencyResolver(string moduleFilePattern)
: base()
{
Kernel = new StandardKernel();
Kernel.Load(moduleFilePattern);
}
public override object GetService(Type serviceType)
{
var service = Kernel.TryGet(serviceType) ?? base.GetService(serviceType);
return service;
}
public override IEnumerable<object> GetServices(Type serviceType)
{
IEnumerable<object> services = Kernel.GetAll(serviceType).ToList();
if (services.IsEmpty())
{
services = base.GetServices(serviceType) ?? services;
}
return services;
}
public System.Web.Http.Dependencies.IDependencyScope BeginScope()
{
return this;
}
public void Dispose()
{ }
}
then in your startup class you should register NinjectDependencyResolver for both WebApi and SignalR, like this:
public void Configuration(IAppBuilder app)
{
var dependencyResolver = new NinjectDependencyResolver("*.dll");
var httpConfiguration = new HttpConfiguration();
httpConfiguration.DependencyResolver = dependencyResolver;
app.UseWebApi(httpConfiguration);
var hubConfig = new HubConfiguration { Resolver = dependencyResolver };
app.MapSignalR(hubConfig);
}
I have a self hosted ServiceStack application, and I try to build ISession per request. I suppose the following will work:
Bind<ISession>()
.ToMethod(NapraviSesiju)
.InNamedScope(ControllerScope)
.InScope(s => ReuseScope.Request)
.OnActivation(s => s.BeginTransaction())
.OnDeactivation(s =>
{
if (!s.Transaction.IsActive) return;
try
{
s.Transaction.Commit();
}
catch (Exception e)
{
s.Transaction.Rollback();
}
});
private ISession NapraviSesiju(IContext kontekst)
{
var sesija = kontekst.Kernel.Get<ISessionFactory>().OpenSession();
return sesija;
}
This works, but request deactivation is not instant (it happens after 30 seconds, or 1 minute, and some requests don't deactivate at all).
Can someone please tell me the correct way to handle NHibernate Sessions this way?
UPDATE
Can I use this then:
public class AppHost : AppHostHttpListenerBase
{
private IKernel _jezgro;
public override void Configure(Container container)
{
_jezgro = new StandardKernel(new NHibernateModul());
container.Adapter = new NinjectIocAdapter(_jezgro);
}
public override void Release(object instance)
{
_jezgro.Release(((IHasSession)instance).Sesija); //Release Sesija from SomeServis object below
}
}
public class SomeServis : RestServiceBase<Some>, IHasSession //implements NHibernate Session
{
public ISession Sesija { get; set; } //IHasSession implementation. Injected by Ninject.
}
Bind<ISession>()
.ToMethod(NapraviSesiju)
.InScope(s => ReuseScope.Request) //reuse per request scope. Is this really needed, since release is happening at Release in AppHost?
.OnActivation(s => s.BeginTransaction())
.OnDeactivation(s =>
{
if (!s.Transaction.IsActive) return;
try
{
s.Transaction.Commit();
}
catch (Exception)
{
s.Transaction.Rollback();
}
});
The bottom of the IOC Container wiki page explains the Release behavior of IOC resources. The easiest way to handle disposed resources is to implement the IRelease method and delegate the Released instances back into Ninject, e.g:
public class NinjectIocAdapter : IContainerAdapter, IRelease
{
private readonly IKernel kernel;
//...
public void Release(object instance)
{
this.kernel.Release(instance);
}
}