Persistence of service for multiple requests - web-services

Question

I had originally thought that a particular "service interface" and in my example one that inherits from ServiceStack.ServiceInterface.Service is recreated with every request. I recently found out that perhaps it's not the case, as dependencies( and members in general) are retaining internal state. I was just hoping if someone could point me in the right direction as to expected behavior and why it behaves this way. I'm primarily interested in two scenarios, one for IIS hosting, and one for VS hosting / debugging.

Answer 1

A Service in ServiceStack is registered and autowired like any other IOC dependency. Every request a new instance of the Service is created and autowired with its dependencies.
Whether the service is autowired with existing instances or not depends on how the dependency is registered, e.g if you use the built-in Funq IOC:
By default dependencies are registered with Singleton scope, i.e. it will inject the same instance everytime:
container.Register<IFoo>(c => new Foo());
container.Register<IFoo>(c => new Foo()).ReusedWithin(ReuseScope.Container);
You can also specify RequestScope so a new instance is created and injected per request:
container.Register<IFoo>(c => new Foo()).ReusedWithin(ReuseScope.Request);
Finally there's transient scope where a new instance is created and injected each time:
container.Register<IFoo>(c => new Foo()).ReusedWithin(ReuseScope.None);
To re-cap a new instance of your service is indeed created per request, but whether you get a new instance or not depends on the Registration scope of your dependencies:
public class MyService : Service {
public IFoo Foo { get; set; } // auto-wired using above registration rules
}