Call WCF service from a background thread - multithreading

Question

I’m working on a piece of code which would take in an API request to a WebAPI controller and through that invoke a WCF web service. This would block until the WCF service responded and cause issues such as timeouts and performance problems. I can't use async/await for this particular use case for a number of reasons beyond my control.
I’m looking at kicking this WCF call off on a separate thread, so in the WebAPI controller I do something like:
New Thread(()=>{
//Call WCF service here
//Do something with the response
}).Start();
However, the code is blowing up. The line that calls the WCF service was moved into the above codeblock unchanged, but now I’m getting:
Cannot access a disposed object. Object name:
'System.ServiceModel.Channels.ServiceChannel'.
Looking at the stack trace when the exception is thrown, I can see the server stack trace as follows:
Server stack trace: at
System.ServiceModel.Channels.CommunicationObject.ThrowIfDisposedOrImmutable()
at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan
timeout) at
System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call(ServiceChannel
channel, TimeSpan timeout) at
System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan
timeout, CallOnceManager cascade) at
System.ServiceModel.Channels.ServiceChannel.Call(String action,
Boolean oneway, ProxyOperationRuntime operation, Object[] ins,
Object[] outs, TimeSpan timeout) at
System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage
methodCall, ProxyOperationRuntime operation) at
System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage
message)
Im not hugely experienced with WCF so wondered if there was some quirk regarding calling this service in a background thread or if there was something else I needed to do instead?
I’ve tried Googling this but all the results are pertaining to calling a background thread from within a WCF service, not calling a WCF service from a background.
Any ideas?

Answer 1

I am pretty much sure, that you creating instance of WCF service outside thread. So previously it looked like:
using(var client = new WcfServiceClient())
{
client.CallSomeMethod();
}
And you changed it to something like:
using(var client = new WcfServiceClient())
{
new Thread(() => {
client.CallSomeMethod();
}).Start();
}
And what you need to is to move client creation into Thread:
new Thread(() => {
using(var client = new WcfServiceClient())
{
client.CallSomeMethod();
}
}).Start();
}

Answer 2

So I figured this out in the end. It was a Unity problem. For some reason, whereas the existing code was:
container.RegisterType<IMyServiceWrapper, MyServiceImplementation>()
I had to explicitly tell Unity how to resolve the constructor parameter:
container.RegisterType<IMyServiceWrapper, MyServiceImplementation>(
new InjectionConstructor(container.Resolve<IMyDependentService>()));
Unfortunately, I have no idea why this was required or why it fixed it?