How can I use IWantToRunBeforeConfigurationIsFinalized , inject propertys into the handlers *and* continue using the Nservicebus test framework? - autofac

Question

Nervicebus 4.6 Unit Testing issue
I recently discovered IWantToRunBeforeConfigurationIsFinalized to inject propertys into a handler, changed all my service code and now suddenly all my NserviceBus.Test fails.
public void run {
Configure.Instance.Configurer.ConfigureProperty<MyMessage_Handler>(h => h.MyProperty, "somevalue");
}
When i atttempt a unit test
var message = new MyMessage
{
...
...
};
Test.Handler<MyMessage_Handler>().WithExternalDependencies(m =>
{
m.PropertyA = aValue;
m.PropertyB = bValue;
})
.ExpectPublish<MyEvent>(m =>
{
Assert.That(...);
return true;
})
.OnMessage<MyMessage>(message);
I receive the following exception
TestFixture failed: SetUp : System.InvalidOperationException : Cannot
configure properties for a type that hasn't been configured yet:
at
NServiceBus.ObjectBuilder.Autofac.AutofacObjectBuilder.ConfigureProperty(Type
component, String property, Object value) in
y:\BuildAgent\work\31f8c64a6e8a2d7c\src\NServiceBus.Core\ObjectBuilder\Autofac\AutofacObjectBuilder.cs:line
114
However if i configure the bus like this, calling configurecomponent on the handler. The test framework works
This was my original method, it works fine but i prefer the approach of IWantToRunBeforeConfigurationIsFinalized to cleanly seperate the logic.
Configure.With()
.DefaultBuilder()
.PurgeOnStartup(false)
.RunCustomAction(() => Configure.Instance.Configurer.ConfigureComponent<MyMessage_Handler>(DependencyLifecycle.InstancePerUnitOfWork))
.RunCustomAction(() => {
Configure.Instance.Configurer.ConfigureProperty<MyMessage_Handler>(h => h.MyProperty, "myValue");
}
...
How can I use IWantToRunBeforeConfigurationIsFinalized , inject propertys into the handlers and continue using the Nservicebus test framework?

Answer 1

It seems odd to try to configure properties directly on handlers. If it's only needed by one handler, then it should be dealt with in that handler, perhaps in a static constructor in that handler class.
At any rate, you're putting yourself at the mercy of when types are loaded up and registered into the container, which isn't necessarily deterministic across different versions of NServiceBus, and clearly not when dealing with the testing framework.
Instead, what if you created a new class:
public class ReferenceValues
{
public string MyProperty { get; set; }
}
Then, you could register this type normally, from any point in the endpoint startup. Preferably, as an INeedInitialization since most of the extensibility points go away in NServiceBus 5.x and INeedInitialization is really the only game in town.
// V4 code
public class SetupReferenceValues : INeedInitialization
{
public void Init()
{
Configure.Component<ReferenceValues>(DependencyLifecycle.SingleInstance)
.ConfigureProperty(rv => rv.MyProperty, "myValue");
}
}
Then, in your handler:
public class MyHandler : IHandleMessages<MyMessage>
{
public ReferenceValues Values { get; set; }
public void Handle(MyMessage message)
{
Console.WriteLine(Values.MyProperty);
}
}
I believe this should work from the testing framework as well.