WCF service dependency injection
// You'll need to implement a combination of custom ServiceHostFactory, ServiceHost and IInstanceProvider.
// Given a service with this constructor signature:
//public MyService(IDependency dep)
// Register MyServiceHostFactory in your MyService.svc file, or use MyServiceHost directly in code for self-hosting scenarios.
public class MyServiceHostFactory : ServiceHostFactory
{
private readonly IDependency dep;
public MyServiceHostFactory()
{
this.dep = new MyClass();
}
protected override ServiceHost CreateServiceHost(Type serviceType,
Uri[] baseAddresses)
{
return new MyServiceHost(this.dep, serviceType, baseAddresses);
}
}
public class MyServiceHost : ServiceHost
{
public MyServiceHost(IDependency dep, Type serviceType, params Uri[] baseAddresses)
: base(serviceType, baseAddresses)
{
if (dep == null)
{
throw new ArgumentNullException("dep");
}
foreach (var cd in this.ImplementedContracts.Values)
{
cd.Behaviors.Add(new MyInstanceProvider(dep));
}
}
}
public class MyInstanceProvider : IInstanceProvider, IContractBehavior
{
private readonly IDependency dep;
public MyInstanceProvider(IDependency dep)
{
if (dep == null)
{
throw new ArgumentNullException("dep");
}
this.dep = dep;
}
#region IInstanceProvider Members
public object GetInstance(InstanceContext instanceContext, Message message)
{
return this.GetInstance(instanceContext);
}
public object GetInstance(InstanceContext instanceContext)
{
return new MyService(this.dep);
}
public void ReleaseInstance(InstanceContext instanceContext, object instance)
{
var disposable = instance as IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
}
#endregion
#region IContractBehavior Members
public void AddBindingParameters(ContractDescription contractDescription, ServiceEndpoint endpoint, BindingParameterCollection bindingParameters)
{
}
public void ApplyClientBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, ClientRuntime clientRuntime)
{
}
public void ApplyDispatchBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, DispatchRuntime dispatchRuntime)
{
dispatchRuntime.InstanceProvider = this;
}
public void Validate(ContractDescription contractDescription, ServiceEndpoint endpoint)
{
}
#endregion
}