WCF custom service host factory not being called - wcf

Question

I've implemented a WCF Service Library (.Net 4.5) which works fine.
Then I tried to implement Unity DI using a custom Servcie Host Factory. Debugging application I noticed that CreateServiceHost method in my factory not being called so that my service constructor which uses a dependency as parameter not being called and I get this error:
"System.InvalidOperationException: The service type provided could not be loaded as a service because it does not have a default (parameter-less) constructor. To fix the problem, add a default constructor to the type, or pass an instance of the type to the host."
my custom Service Host Factory:
namespace Amir.CodingChallenge.WcfService.Unity
{
public class UnityServiceHostFactory : ServiceHostFactory
{
protected override ServiceHost CreateServiceHost(Type serviceType, Uri[] baseAddresses)
{
UnityServiceHost serviceHost = new UnityServiceHost(serviceType,baseAddresses);
// I register types in RegisterComponents method by coding.
serviceHost.Container = UnityConfig.RegisterComponents();
return serviceHost;
}
}
}
my service:
namespace Amir.CodingChallenge.WcfService
{
public class MovieService : IMovieService
{
IShowService showService;
public MovieService(IShowService showService)
{
this.showService = showService;
}
...
}
}
and App.Config:
<system.serviceModel>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true">
<serviceActivations>
<add service="Amir.CodingChallenge.WcfService.MovieService"
relativeAddress="./MovieService.svc"
factory="Amir.CodingChallenge.WcfService.Unity.UnityServiceHostFactory"/>
</serviceActivations>
</serviceHostingEnvironment>
<services>
<service name="Amir.CodingChallenge.WcfService.MovieService">
<endpoint address="" binding="wsHttpBinding" contract="Amir.CodingChallenge.WcfService.IMovieService">
<identity>
<dns value="localhost" />
</identity>
</endpoint>
<endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
<host>
<baseAddresses>
<add baseAddress="http://localhost:49875/Amir.CodingChallenge.WcfService/MovieService/" />
</baseAddresses>
</host>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior>
<!-- To avoid disclosing metadata information,
set the values below to false before deployment -->
<serviceMetadata httpGetEnabled="True" httpsGetEnabled="True"/>
<!-- To receive exception details in faults for debugging purposes,
set the value below to true. Set to false before deployment
to avoid disclosing exception information -->
<serviceDebug includeExceptionDetailInFaults="False" />
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
"Amir.CodingChallenge.WcfService" is my app Assembly name.
Am I doing something wrong in config? Any help would be appreciated.
And the rest of my codes to give further info in below.
UnityConfig class:
namespace Amir.CodingChallenge.WcfService.Unity
{
public static class UnityConfig
{
static UnityContainer container;
public static UnityContainer RegisterComponents()
{
if (container == null)
container = new UnityContainer();
RegisterTypes();
return container;
}
private static void RegisterTypes()
{
container.RegisterType<IShowService, ShowService>(new HierarchicalLifetimeManager());
}
}
}
UnityServiceHost class:
namespace Amir.CodingChallenge.WcfService.Unity
{
public class UnityServiceHost : ServiceHost
{
public UnityContainer Container { set; get; }
public UnityServiceHost()
: base()
{
Container = new UnityContainer();
}
public UnityServiceHost(Type serviceType, params Uri[] baseAddresses)
: base(serviceType, baseAddresses)
{
Container = new UnityContainer();
}
protected override void OnOpening()
{
if (this.Description.Behaviors.Find<UnityServiceBehavior>() == null)
this.Description.Behaviors.Add(new UnityServiceBehavior(Container));
base.OnOpening();
}
}
}
UnityServiceBehavior class:
namespace Amir.CodingChallenge.WcfService.Unity
{
public class UnityServiceBehavior : IServiceBehavior
{
public UnityInstanceProvider InstanceProvider { get; set; }
private ServiceHost serviceHost = null;
public UnityServiceBehavior()
{
InstanceProvider = new UnityInstanceProvider();
}
public UnityServiceBehavior(UnityContainer unity)
{
InstanceProvider = new UnityInstanceProvider();
InstanceProvider.Container = unity;
}
public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
{
foreach (ChannelDispatcherBase cdb in serviceHostBase.ChannelDispatchers)
{
ChannelDispatcher cd = cdb as ChannelDispatcher;
if (cd != null)
{
foreach (EndpointDispatcher ed in cd.Endpoints)
{
InstanceProvider.ServiceType = serviceDescription.ServiceType;
ed.DispatchRuntime.InstanceProvider = InstanceProvider;
}
}
}
}
public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase) { }
public void AddBindingParameters(
ServiceDescription serviceDescription,
ServiceHostBase serviceHostBase,
Collection<ServiceEndpoint> endpoints,
BindingParameterCollection bindingParameters)
{
}
}
}
UnityInstanceProvider class:
namespace Amir.CodingChallenge.WcfService.Unity
{
public class UnityInstanceProvider : IInstanceProvider
{
public UnityContainer Container { set; get; }
public Type ServiceType { set; get; }
public UnityInstanceProvider()
: this(null)
{
}
public UnityInstanceProvider(Type type)
{
ServiceType = type;
Container = new UnityContainer();
}
#region IInstanceProvider Members
public object GetInstance(InstanceContext instanceContext, Message message)
{
return Container.Resolve(ServiceType);
}
public object GetInstance(InstanceContext instanceContext)
{
return GetInstance(instanceContext, null);
}
public void ReleaseInstance(InstanceContext instanceContext, object instance)
{
}
#endregion
}
}

Answer 1

Make sure that you are linking to the UnityServiceHostFactory in your Service Markup
<%# ServiceHost
Language="C#" Debug="true"
Service="WcfServiceApplication.Implementation.ProductService"
Factory="WcfServiceApplication.DependencyInjection.WCF.UnityServiceHostFactory"
%>
Finding the Markup code was the issue for me. Just right click on the Svc and click "View Markup"
Then you can add in the UnityServiceHostFactory as the Factory value
Link to Source of Answer

Answer 2

Ensure that the build is copying the project dll to the correct location.
In my case, I was copying for 'bin\debug' and the correct would be 'bin\'.