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Limit Ninject.MockingKernel to mocking classes in my own namespaces only

I've just switched to using the NInject.MockingKernel extension for my tests (NSubstitute).
However, it makes very hard to run my Web API integration tests because it will return mocks for all Web API interfaces also.
Can I automatically limit its application only to namespaces of my own?

I don't see how that is possible out of the box. Although it's not very hard to create such a kernel on your own.
This sample is of course very minimalistic though, but it should show you how it could be done. Or maybe there is someone with more knowledge of the Ninject internals.
public class NamespaceFilteringMockMissingBindingsResolver : MockMissingBindingResolver
{
public NamespaceFilteringMockMissingBindingsResolver(IMockProviderCallbackProvider mockProviderCallbackProvider)
: base(mockProviderCallbackProvider)
{
}
protected override bool TypeIsInterfaceOrAbstract(Type service)
{
return base.TypeIsInterfaceOrAbstract(service) && service.Namespace != null && service.Namespace.StartsWith("YourNamespace");
}
}
public class CustomNSubstituteMockingKernel : NSubstituteMockingKernel
{
public CustomNSubstituteMockingKernel()
{
this.AddComponents();
}
public CustomNSubstituteMockingKernel(INinjectSettings settings, params INinjectModule[] modules)
: base(settings, modules)
{
this.AddComponents();
}
private new void AddComponents()
{
this.Components.RemoveAll<IMissingBindingResolver>();
this.Components.Add<IMissingBindingResolver, SingletonSelfBindingResolver>();
this.Components.Add<IMissingBindingResolver, NamespaceFilteringMockMissingBindingsResolver>();
}
}
Update
You are right, you don't need to create your own kernel. You can also do it like this.
var kernel = new NSubstituteMockingKernel();
kernel.Components.RemoveAll<IMissingBindingResolver>();
kernel.Components.Add<IMissingBindingResolver, SingletonSelfBindingResolver>();
kernel.Components.Add<IMissingBindingResolver, NamespaceFilteringMockMissingBindingsResolver>();
Creating your own kernel might just be more handy than always writing those extra lines. Or you create some kind of factory method.

Using Ninject in .NET RESTful application?

I'm new to RESTful services and haven't had to freshly wire up a stack using IoC in a while, so this is giving me a mild stroke.
I have a WCF service that looks like this (simplified):
public interface IESIID
{
[OperationContract]
[WebGet(UriTemplate = "/{guid}/{id}", ResponseFormat = WebMessageFormat.Json,
BodyStyle = WebMessageBodyStyle.Wrapped)]
Message LookupESIID(string guid, string id);
}
public class ESIID : BaseREST<ESI>, IESIID
{
private readonly ITXESIIDService _bllSvc;
public ESIID(ITXESIIDService svc)
{
_bllSvc = svc;
}
public Message LookupESIID(string guid, string id)
{
return GetById(guid, id);
}
private Message GetById(string guid, string id)
{
apiAuthentication = new APIKeyAuthentication();
if (!apiAuthentication.IsValidAPIKey(guid))
return APIError();
//_bllSvc = new TXESIIDService(); <--- WANTING TO AVOID THIS!!!!
var results = _bllSvc.SelectByID(id);
return results.Count == 0 ? NoResults() : CreateMessage(results);
}
}
Fine, that's pretty straight forward. I did add a constructor parameter because with the call to the BLL TXESIIDService method.
So now, I've altered my Global file for Ninject which now looks something like this:
public class Global : NinjectWcfApplication
{
protected override void Application_Start(object sender, EventArgs e)
{
RegisterRoutes();
}
protected override IKernel CreateKernel()
{
return new StandardKernel(new RestServiceModel());
}
private static void RegisterRoutes()
{
RouteTable.Routes.Add(new ServiceRoute("ESIID", new NinjectServiceHostFactory(), typeof(ESIID)));
}
}
and also added my module:
public class RestServiceModel : NinjectModule
{
public override void Load()
{
Bind<ITXESIIDService>().To<TXESIIDService>();
Bind<IDoNotSolicitService>().To<DoNotSolicitService>();
}
}
And for troubleshooting I added by own NinjectServiceHostFactory
public class NinjectServiceHostFactory : WebServiceHostFactory
{
protected override ServiceHost CreateServiceHost(Type serviceType, Uri[] baseAddresses)
{
var serviceTypeParameter = new ConstructorArgument("serviceType", serviceType);
var baseAddressesParameter = new ConstructorArgument("baseAddresses", baseAddresses);
return KernelContainer.Kernel.Get<NinjectServiceHost>(serviceTypeParameter, baseAddressesParameter);
}
}
When I run this as in I get an error that the line:
return KernelContainer.Kernel.Get<NinjectServiceHost>(serviceTypeParameter, baseAddressesParameter);
cannot be null.
Obviously I'm missing something here, but I can't figure out what. I've tried various things at this point and most examples I see are for WCF services and the RESTful ones I've manage to find are just a bit too geared for those familiar w/Ninject or IoC regulars.
Also, In my Business and Data layers (using entity framework), I'm looking to implement Ninject there as well, is it best practice to have the layers wired up separately or is it possible to do it all in one spot?
Thanks.
UPDATE 1
I have corrected the binding issue, but this still bombs on me. I'm using Ninject.Extensions.Wcf and it's bombing looking for NinjectWcfApplication.cs file which doesn't seem right at all. I used NuGet to include a package for Ninject, could this be a version issue?

This may be a typo, but are you meaning to bind interfaces to themselves in your module? Usually you bind an interface to a concrete type. If Ninject tries to instantiate an interface type, it will definitely fail, and depending on specific error-handling behavior of your Ninject setup it'll either throw out or return null. So, make sure the module is configured to look for a real class:
public class RestServiceModel : NinjectModule
{
public override void Load()
{
Bind<ITXESIIDService>().To<TXESIIDService>();
...
}
}

You always have to call the base method when overriding a virtual method. See Application_Start().

Regarding your update: I am new to ninject so I don't know anything about older versions but I suppose you try out the Example Ninject Extensions first. If they run, you know it must be something else.

Async WCF: wait for another call

We have an old Silverlight UserControl + WCF component in our framework and we would like to increase the reusability of this feature. The component should work with basic functionality by default, but we would like to extend it based on the current project (without modifying the original, so more of this control can appear in the full system with different functionality).
So we made a plan, where everything looks great, except one thing. Here is a short summary:
Silverlight UserControl can be extended and manipulated via ContentPresenter at the UI and ViewModel inheritance, events and messaging in the client logic.
Back-end business logic can be manipulated with module loading.
This gonna be okay I think. For example you can disable/remove fields from the UI with overriden ViewModel properties, and at the back-end you can avoid some action with custom modules.
The interesting part is when you add new fields via the ContentPresenter. Ok, you add new properties to the inherited ViewModel, then you can bind to them. You have the additional data. When you save base data, you know it's succeeded, then you can start saving your additional data (additional data can be anything, in a different table at back-end for example). Fine, we extended our UserControl and the back-end logic and the original userControl still doesn't know anything about our extension.
But we lost transaction. For example we can save base data, but additional data saving throws an exception, we have the updated base data but nothing in the additional table. We really doesn't want this possibility, so I came up with this idea:
One WCF call should wait for the other at the back-end, and if both arrived, we can begin cross thread communication between them, and of course, we can handle the base and the additional data in the same transaction, and the base component still doesn't know anything about the other (it just provide a feature to do something with it, but it doesn't know who gonna do it).
I made a very simplified proof of concept solution, this is the output:
1 send begins
Press return to send the second piece
2 send begins
2 send completed, returned: 1
1 send completed, returned: 2
Service
namespace MyService
{
[ServiceContract]
[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple)]
public class Service1
{
protected bool _sameArrived;
protected Piece _same;
[OperationContract]
public Piece SendPiece(Piece piece)
{
_sameArrived = false;
Mediator.Instance.WaitFor(piece, sameArrived);
while (!_sameArrived)
{
Thread.Sleep(100);
}
return _same;
}
protected void sameArrived(Piece piece)
{
_same = piece;
_sameArrived = true;
}
}
}
Piece (entity)
namespace MyService
{
[DataContract]
public class Piece
{
[DataMember]
public long ID { get; set; }
[DataMember]
public string SameIdentifier { get; set; }
}
}
Mediator
namespace MyService
{
public sealed class Mediator
{
private static Mediator _instance;
private static object syncRoot = new Object();
private List<Tuple<Piece, Action<Piece>>> _waitsFor;
private Mediator()
{
_waitsFor = new List<Tuple<Piece, Action<Piece>>>();
}
public static Mediator Instance
{
get
{
if (_instance == null)
{
lock (syncRoot)
{
_instance = new Mediator();
}
}
return _instance;
}
}
public void WaitFor(Piece piece, Action<Piece> callback)
{
lock (_waitsFor)
{
var waiter = _waitsFor.Where(i => i.Item1.SameIdentifier == piece.SameIdentifier).FirstOrDefault();
if (waiter != null)
{
_waitsFor.Remove(waiter);
waiter.Item2(piece);
callback(waiter.Item1);
}
else
{
_waitsFor.Add(new Tuple<Piece, Action<Piece>>(piece, callback));
}
}
}
}
}
And the client side code
namespace MyClient
{
class Program
{
static void Main(string[] args)
{
Client c1 = new Client(new Piece()
{
ID = 1,
SameIdentifier = "customIdentifier"
});
Client c2 = new Client(new Piece()
{
ID = 2,
SameIdentifier = "customIdentifier"
});
c1.SendPiece();
Console.WriteLine("Press return to send the second piece");
Console.ReadLine();
c2.SendPiece();
Console.ReadLine();
}
}
class Client
{
protected Piece _piece;
protected Service1Client _service;
public Client(Piece piece)
{
_piece = piece;
_service = new Service1Client();
}
public void SendPiece()
{
Console.WriteLine("{0} send begins", _piece.ID);
_service.BeginSendPiece(_piece, new AsyncCallback(sendPieceCallback), null);
}
protected void sendPieceCallback(IAsyncResult result)
{
Piece returnedPiece = _service.EndSendPiece(result);
Console.WriteLine("{0} send completed, returned: {1}", _piece.ID, returnedPiece.ID);
}
}
}
So is it a good idea to wait for another WCF call (which may or may not be invoked, so in a real example it would be more complex), and process them together with cross threading communication? Or not and I should look for another solution?
Thanks in advance,
negra

If you want to extend your application without changing any existing code, you can use MEF that is Microsoft Extensibility Framework.
For using MEF with silverlight see: http://development-guides.silverbaylabs.org/Video/Silverlight-MEF
I would not wait for 2 WCF calls from Silverlight, for the following reasons:
You are making your code more complex and less maintainable
You are storing business knowledge, that two services should be called together, in the client
I would call a single service that aggreagated the two services.

It doesn't feel like a great idea to me, to be honest. I think it would be neater if you could package up both "partial" requests in a single "full" request, and wait for that. Unfortunately I don't know the best way of doing that within WCF. It's possible that there's a generalized mechanism for this, but I don't know about it. Basically you'd need some loosely typed service layer where you could represent a generalized request and a generalized response, routing the requests appropriately in the server. You could then represent a collection of requests and responses easily.
That's the approach I'd look at, personally - but I don't know how neatly it will turn out in WCF.

Can I use WCF duplex binding to relay message?

I have a Client Application, a server and another client, lets call it third party. I have a callback interface as part of my contract that is implemented both by the third party and the client.
The third party will call a server operation(method) then the server will trigger a callback but instead of calling the callback of the third party, it will call the callback implementation of the client.

Yes, you can absolutely do that.
The easiest way is to implement your service as a PerSession service, and capture the callback context on initialization/construction. Typically I will add the service object (which really represents a connection at that point) to an internal core object.
Then, when you get in a message from a client, you can make a call to any of the service objects (not through the contract), and internally forward the data to the associated client.
This is a pretty minimal implementation of the concept, without exception handling, and some pretty bad design (static class BAD!). I haven't tested this, but the principles should hold even if I missed crossing an i or dotting a t. This example also forwards the calls to all clients, but selecting an individual client follows the same basic pattern.
Trying to do this with a singleton service will be more difficult, and a per-call service obviously won't work :)
[ServiceContract(CallbackContract = typeof(ICallback))]
public interface IContract
{
[OperationContract(IsOneWay = true)]
void SendTheData(string s);
}
public interface ICallback
{
[OperationContract(IsOneWay = true)]
void ForwardTheData(string s);
}
[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Reentrant, InstanceContextMode = InstanceContextMode.PerSession)]
public class ServiceConnection : IContract
{
private ICallback m_callback;
public ServiceConnection()
{
m_callback = OperationContext.Current.GetCallbackChannel<ICallback>();
ServiceCore.Add(this);
}
public void SendTheData(string s)
{
ServiceCore.DataArrived(s);
}
public void SendToClient(string s)
{
m_callback.ForwardTheData(s);
}
}
static public class ServiceCore
{
static private List<ServiceConnection> m_connections = new List<ServiceConnection>();
public static void DataArrived(string s)
{
foreach(ServiceConnection conn in m_connections)
{
conn.SendTheData(s);
}
}
public static void Add(ServiceConnection connection)
{
m_connections.Add(connection);
}
}

From a quick read of the Microsoft Duplex service documentation I don't think that will do what you want. There could be some other clever Kung Fu WCF way to do it but in my case I created a "PassThruService" for the server that implemented the same contract as the real service and sent any requests received onto the client.
This is a part of my code that explains the thrust of it.
private const int OPERATION_TIMEOUT = 5000;
private MyServiceClient m_client = new MyServiceClient();
public bool IsAlive() {
try {
logger.Debug("PassThruService IsAlive.");
bool isAlive = false;
ManualResetEvent isAliveMRE = new ManualResetEvent(false);
m_client.IsAliveComplete += (s, a) => { isAlive = a.Result; isAliveMRE.Set(); };
m_client.IsAliveAsync();
if (isAliveMRE.WaitOne(OPERATION_TIMEOUT)) {
return isAlive;
}
else {
throw new TimeoutException();
}
}
catch (Exception excp) {
logger.Error("Exception PassThruService IsAlive. " + excp.Message);
throw;
}

I don't fully see what you're really asking here.... but I'll try to give some tips anyway.
Relaying messages or routing is not very well supported in WCF in .NET 3.5 - the infrastructure is there, but it's still a lot of work to set it up manually.
The best intro I know into this topic for WCF in .NET 3.5 is a two-part article by Michele Leroux Bustamante on MSDN magazine:
Building a WCF Router, Part 1
Building a WCF Router, Part 2
Part 2 has a section on duplex routers - does that help you in your quest at all??
WCF in .NET 4.0 promises to bring additional support for routing - there will be a RoutingService base class which can be leveraged to write routing services, and it will allow for configurable, content- or metadata-based routing - whatever it is that you need.
.NET 4.0 is scheduled to be released sometime later this year (2009) - hopefully! So while this is still the future, it's looking rosy!
Marc

I think I found the solution..
Here's the link.
http://msdn.microsoft.com/en-us/magazine/cc163537.aspx
Try to look at figure 6. That's what I'm trying to achieve.

.Net Remoting to WCF Challenge!

I am trying to migrate my .net remoting code to wcf but I'm finding it difficult. Can someone help me migrate this simple Remoting based program below to use WCF? The program implements a simple publisher/subscriber pattern where we have a single TemperatureProviderProgram that publishers to many TemperatureSubcriberPrograms that subcribe to the TemperatureProvider.
To run the programs:
Copy the TemperatureProviderProgram and TemperatureSubcriberProgram into seperate console application projects.
Copying to remaining classes and interfaces into a common Class Library project then add a reference to System.Runtime.Remoting library
Add a reference to the Class Library project from the console app projects.
Complie and run 1 TemperatureProviderProgram and multiple TemperatureSubcriberProgram.
Please note no IIS or xml should be used. Thanks in advance.
public interface ITemperatureProvider
{
void Subcribe(ObjRef temperatureSubcriber);
}
[Serializable]
public sealed class TemperatureProvider : MarshalByRefObject, ITemperatureProvider
{
private readonly List<ITemperatureSubcriber> _temperatureSubcribers = new List<ITemperatureSubcriber>();
private readonly Random randomTemperature = new Random();
public void Subcribe(ObjRef temperatureSubcriber)
{
ITemperatureSubcriber tempSubcriber = (ITemperatureSubcriber)RemotingServices.Unmarshal(temperatureSubcriber);
lock (_temperatureSubcribers)
{
_temperatureSubcribers.Add(tempSubcriber);
}
}
public void Start()
{
Console.WriteLine("TemperatureProvider started...");
BinaryServerFormatterSinkProvider provider = new BinaryServerFormatterSinkProvider();
provider.TypeFilterLevel = System.Runtime.Serialization.Formatters.TypeFilterLevel.Full;
TcpServerChannel tcpChannel = new TcpServerChannel("TemperatureProviderChannel", 5001, provider);
ChannelServices.RegisterChannel(tcpChannel, false);
RemotingServices.Marshal(this, "TemperatureProvider", typeof(ITemperatureProvider));
while (true)
{
double nextTemp = randomTemperature.NextDouble();
lock (_temperatureSubcribers)
{
foreach (var item in _temperatureSubcribers)
{
try
{
item.OnTemperature(nextTemp);
}
catch (SocketException)
{}
catch(RemotingException)
{}
}
}
Thread.Sleep(200);
}
}
}
public interface ITemperatureSubcriber
{
void OnTemperature(double temperature);
}
[Serializable]
public sealed class TemperatureSubcriber : MarshalByRefObject, ITemperatureSubcriber
{
private ObjRef _clientRef;
private readonly Random portGen = new Random();
public void OnTemperature(double temperature)
{
Console.WriteLine(temperature);
}
public override object InitializeLifetimeService()
{
return null;
}
public void Start()
{
BinaryServerFormatterSinkProvider provider = new BinaryServerFormatterSinkProvider();
provider.TypeFilterLevel = System.Runtime.Serialization.Formatters.TypeFilterLevel.Full;
int port = portGen.Next(1, 65535);
TcpServerChannel tcpChannel = new TcpServerChannel(string.Format("TemperatureSubcriber_{0}", Guid.NewGuid()), port, provider);
ChannelServices.RegisterChannel(tcpChannel, false);
ITemperatureProvider p1 = (ITemperatureProvider)RemotingServices.Connect(typeof(ITemperatureProvider), "tcp://localhost:5001/TemperatureProvider");
_clientRef = RemotingServices.Marshal(this, string.Format("TemperatureSubcriber_{0}_{1}.rem", Environment.MachineName, Guid.NewGuid()));
p1.Subcribe(_clientRef);
}
}
public class TemperatureProviderProgram
{
static void Main(string[] args)
{
TemperatureProvider tp = new TemperatureProvider();
tp.Start();
}
}
public class TemperatureSubcriberProgram
{
static void Main(string[] args)
{
Console.WriteLine("Press any key to start TemperatureSubcriber.");
Console.ReadLine();
TemperatureSubcriber ts = new TemperatureSubcriber();
ts.Start();
Console.ReadLine();
}
}

In WCF, with a "push" from the server you're really talking about duplex comms; the MarshalByRefObject is largely redundant here (AFAIK). The page here discusses various scenarios, including duplex/callbacks.
If the issue is xml (for some philosophical reason), then simply using NetDataContractSerializer rather than DataContractSerializer might help.
The other approach is to have the clients "pull" data periodically; this works well if you need to support basic http, etc.

What it sounds like you want to do is use WCF NetTcpBinding with Callbacks.
Take a look at this: http://www.codeproject.com/KB/WCF/publisher_subscriber.aspx
"Learning WCF" by Michele Bustamante is also very good. You can get Chpt1 for VS2008 at her website along with the code for the book. Chpt1 will explain/demo setting up connections and such. She also has downloadable sample code. One of the Samples is a DuplexPublishSubscribe.

You will need to modify your logic a bit. If you want to migrate this app to WCF. You will need to have clients pull data from the service at regular intervals.
You will also need a Windows service or application to host the WCF like the console you are using in the previous code.

Well I build real time systems so polling is not an option - I need to push data.
Also I am finding there is no WCF equivalent of System.Runtime.Remoting.ObjRef! This is an extremely useful type that encapsulates a service endpoint and can be serialise and passed around the network to other remoting service.
Think I’ll be sticking with good old remoting until the ObjRef equivalent is introduced.

Yes it is true, just one correction..
ObjRefs are created automatically when any MarshalByRefObject derived object is going outside the appdomain.
So in this case your ITemperatureProvider interface Subscribe method shoud take ITemperatureSubscriber instead of objref.
And then on client side just call p1.Subscribe(this) and the remoting layer will generate ObjRef from the object that will be serialized and sent. (sending b reference)