CODEWITHSUNDEEP
wcfninject
stevehayter
stevehayter

Reputation: 816

WCF & Ninject - Getting Ninject Kernel Into An IDispatchMessageInspector Instance

I've currently rigged up Ninject into a WCF application (using ninject.extensions.wcf), and the basics are working fine. However, I've added a custom IDispatchMessageInspector and IServiceBehavior in order to authenticate each service call (by check the database against some credentials), but I'm not entirely sure how to get Ninject working within the IDispatchMessageInspector.

The code I have so far is:

public class MyServiceInspector: IDispatchMessageInspector
{
    #region Methods

    public object AfterReceiveRequest(ref Message request, IClientChannel channel, InstanceContext instanceContext)
    {
        // TODO: Get credentials from request here, and hit database.

        return null;
    }

    public void BeforeSendReply(ref Message reply, object correlationState)
    {
        // Do nothing
    } 

   #endregion
}

The IServiceBehavior which initiates this is as follows:

public class MyServiceBehaviour : Attribute, IServiceBehavior
{
    #region Methods

    public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
    {
        // Do nothing
    }

    public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
    {
        // Loop through channels and endpoints
        foreach (ChannelDispatcher cDispatcher in serviceHostBase.ChannelDispatchers)
        {
            foreach (EndpointDispatcher eDispatcher in cDispatcher.Endpoints)
            {
                // Add credentials inspector
                eDispatcher.DispatchRuntime.MessageInspectors.Add(new MyServiceInspector());
            }
        }
    }

    public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
    {
        // Do nothing
    }

    #endregion
}

I've scoured the internet looking for examples, but I can't seem to find anything. Is this even possible?

Upvotes: 1

Views: 575

Answers (2)

tlemster
tlemster

Reputation: 59

I know this answer is very late, but hopefully it helps other people coming across this issue.

I had the same problem today.. I needed a message inspector with injected dependencies. They added a NinjectBehaviorExtensionElement class to Ninjext.Extensions.WCF from version 3.2. So here's how i injected dependencies in my Message Inspector:

The Message Inspector:

 public class MyMessageInspector : IDispatchMessageInspector
 {
    public MyMessageInspector(IInjectedDependency injectedDependency)
    {

    }

    public object AfterReceiveRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel, System.ServiceModel.InstanceContext instanceContext)
    {
    }

    public void BeforeSendReply(ref System.ServiceModel.Channels.Message reply, object correlationState)
    {
    }
 }

The Behavior:

public class MyMessageInspectionBehavior : IEndpointBehavior
{
    private readonly IDispatchMessageInspector _messageInspector;

    public MyMessageInspectionBehavior(IDispatchMessageInspector messageInspector)
    {
        _messageInspector = messageInspector;
    }

    public void AddBindingParameters(ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection bindingParameters)
    {
    }

    public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
    {
    }

    public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
    {
        endpointDispatcher.DispatchRuntime.MessageInspectors.Add(_messageInspector);
    }

    public void Validate(ServiceEndpoint endpoint)
    {
    }

}

The Ninject Binding:

this.Bind<IDispatchMessageInspector>()
    .To<MyMessageInspector>()
    .WhenInjectedInto<IEndpointBehavior>();

The last step is the Configuration:

<system.serviceModel>
<extensions>
  <behaviorExtensions>
    <add name="MyCustomMessageInspector" 
         type="Ninject.Extensions.Wcf.BaseNinjectBehaviorExtensionElement+NinjectBehaviorExtensionElement`1[[MyNamespace.MyMessageInspectionBehavior, MyAssemblyName]], Ninject.Extensions.Wcf" />
  </behaviorExtensions>
</extensions>
<behaviors>
  <endpointBehaviors>
    <behavior>
      <MyCustomMessageInspector />
    </behavior>
  </endpointBehaviors>

Upvotes: 2

stevehayter
stevehayter

Reputation: 816

I have parked this for now, as there doesn't seem to be any solution. I am simply connecting to my context directly with a view to improving it in the future.

Upvotes: 0

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