Multiple instantiation when trying to use ServiceHostFactory to create a DiscoveryProxy service

[Hainesy]

I have a service that inherits from System.ServiceModel.Discovery.DiscoveryProxy.

When I plug in a ServiceHostFactory to the service activation to create a UnityServiceHost, this works, but something else in the pipeline is also trying to instantiate a second instance of the service, requiring a default parameterless constructor. I haven't had a problem with my other services using this approach.

The stack trace that is creating an instance of the service using the empty constructor is as follows:

at MyNameSpace.DiscoveryProxyService..ctor()
at CreateMyNameSpace.DiscoveryProxyService()
at System.ServiceModel.InstanceContext.GetServiceInstance(Message message)
at System.ServiceModel.Dispatcher.InstanceBehavior.EnsureServiceInstance(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage41(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage11(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)
at System.ServiceModel.Dispatcher.ChannelHandler.DispatchAndReleasePump(RequestContext request, Boolean cleanThread, OperationContext currentOperationContext)
at System.ServiceModel.Dispatcher.ChannelHandler.HandleRequest(RequestContext request, OperationContext currentOperationContext) at System.ServiceModel.Dispatcher.ChannelHandler.AsyncMessagePump(IAsyncResult result)
at System.ServiceModel.Dispatcher.ChannelHandler.OnAsyncReceiveComplete(IAsyncResult result)
at System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result)
at System.Runtime.AsyncResult.Complete(Boolean completedSynchronously)
at System.ServiceModel.Channels.TransportDuplexSessionChannel.TryReceiveAsyncResult.OnReceive(IAsyncResult result)
at System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result) 
at System.Runtime.AsyncResult.Complete(Boolean completedSynchronously)
at System.ServiceModel.Channels.SynchronizedMessageSource.ReceiveAsyncResult.OnReceiveComplete(Object state)
at System.ServiceModel.Channels.SessionConnectionReader.OnAsyncReadComplete(Object state)
at System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result) 
at System.Net.LazyAsyncResult.Complete(IntPtr userToken) 
at System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken) 
at System.Net.Security.NegotiateStream.ProcessFrameBody(Int32 readBytes, Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.NegotiateStream.ReadCallback(AsyncProtocolRequest asyncRequest) 
at System.Net.AsyncProtocolRequest.CompleteRequest(Int32 result) 
at System.Net.FixedSizeReader.CheckCompletionBeforeNextRead(Int32 bytes) 
at System.Net.FixedSizeReader.ReadCallback(IAsyncResult transportResult) 
at System.Runtime.AsyncResult.Complete(Boolean completedSynchronously) 
at System.ServiceModel.Channels.ConnectionStream.IOAsyncResult.OnAsyncIOComplete(Object state) 
at System.Net.Sockets.SocketAsyncEventArgs.OnCompleted(SocketAsyncEventArgs e) 
at System.Net.Sockets.SocketAsyncEventArgs.FinishOperationSuccess(SocketError socketError, Int32 bytesTransferred, SocketFlags flags) 
at System.Net.Sockets.SocketAsyncEventArgs.CompletionPortCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)

And the one that is correctly using the ServiceHostFactory:

at MyNameSpace.DiscoveryProxyService..ctor(IDiscoveryPersistence persistence)
at lambda_method(Closure , IBuilderContext )
at Microsoft.Practices.ObjectBuilder2.DynamicBuildPlanGenerationContext.<>c__DisplayClass1.<GetBuildMethod>b__0(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context) 
at Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) 
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides) 
at Microsoft.Practices.Unity.UnityContainer.Resolve(Type t, String name, ResolverOverride[] resolverOverrides) 
at MyNameSpace.UnityServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses)
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) 
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(ServiceActivationInfo serviceActivationInfo, EventTraceActivity eventTraceActivity) 
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) 
at System.ServiceModel.ServiceHostingEnvironment.EnsureServiceAvailableFast(String relativeVirtualPath, EventTraceActivity eventTraceActivity) 
at System.ServiceModel.Channels.SharedTcpTransportManager.OnDuplicatedVia(Uri via) 
at System.ServiceModel.Channels.SharedConnectionListener.SharedListenerProxy.HandleOnVia(DuplicateContext duplicateContext) 
at System.ServiceModel.Channels.SharedConnectionListener.SharedListenerProxy.System.ServiceModel.Activation.IConnectionDuplicator.BeginDuplicate(DuplicateContext duplicateContext, AsyncCallback callback, Object state) 
at AsyncInvokeBeginBeginDuplicate(Object , Object[] , AsyncCallback , Object )
at System.ServiceModel.Dispatcher.AsyncMethodInvoker.InvokeBegin(Object instance, Object[] inputs, AsyncCallback callback, Object state)
at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc) 
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage11(MessageRpc& rpc) 
at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet) 
at System.ServiceModel.Dispatcher.ChannelHandler.DispatchAndReleasePump(RequestContext request, Boolean cleanThread, OperationContext currentOperationContext) 
at System.ServiceModel.Dispatcher.ChannelHandler.HandleRequest(RequestContext request, OperationContext currentOperationContext) 
at System.ServiceModel.Dispatcher.ChannelHandler.AsyncMessagePump(IAsyncResult result) 
at System.ServiceModel.Dispatcher.ChannelHandler.OnAsyncReceiveComplete(IAsyncResult result) 
at System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result) 
at System.Runtime.AsyncResult.Complete(Boolean completedSynchronously) 
at System.ServiceModel.Channels.TransportDuplexSessionChannel.TryReceiveAsyncResult.OnReceive(IAsyncResult result) 
at System.Runtime.Fx.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result) 
at System.Runtime.AsyncResult.Complete(Boolean completedSynchronously) 
at System.ServiceModel.Channels.SynchronizedMessageSource.ReceiveAsyncResult.OnReceiveComplete(Object state) 
at System.ServiceModel.Channels.SessionConnectionReader.OnAsyncReadComplete(Object state) 
at System.ServiceModel.Channels.PipeConnection.OnAsyncReadComplete(Boolean haveResult, Int32 error, Int32 numBytes) 
at System.ServiceModel.Channels.OverlappedContext.CompleteCallback(UInt32 error, UInt32 numBytes, NativeOverlapped* nativeOverlapped) 
at System.Runtime.Fx.IOCompletionThunk.UnhandledExceptionFrame(UInt32 error, UInt32 bytesRead, NativeOverlapped* nativeOverlapped) 
at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)

[Uriil]

I am sorry, but I am new to discovery services and won't be able to help you