/// <summary>
/// Creates middleware object from descriptor
/// </summary>
private IMiddleware CreateInstance(MiddlewareDescriptor descriptor)
{
if (descriptor.Instance != null)
{
return(descriptor.Instance);
}
if (descriptor.ConstructorParameters.Length == 0)
{
return((IMiddleware)Activator.CreateInstance(descriptor.MiddlewareType));
}
object[] parameters = new object[descriptor.ConstructorParameters.Length];
for (int i = 0; i < descriptor.ConstructorParameters.Length; i++)
{
Type type = descriptor.ConstructorParameters[i];
if (typeof(IServiceScope).IsAssignableFrom(type))
{
parameters[i] = _scope;
}
else
{
parameters[i] = _scope.ServiceProvider.GetService(type);
}
}
return((IMiddleware)Activator.CreateInstance(descriptor.MiddlewareType, parameters));
}
/// <summary>
/// Uses singleton middleware objects.
/// Same object is used for all requests
/// </summary>
public void UseMiddleware(IMiddleware middleware)
{
MiddlewareDescriptor desc = new MiddlewareDescriptor
{
Instance = middleware,
MiddlewareType = middleware.GetType(),
ConstructorParameters = null
};
Descriptors.Add(desc);
}
/// <summary>
/// Uses middleware, creates new instance for per request.
/// </summary>
public void UseMiddleware <TMiddleware>() where TMiddleware : IMiddleware
{
ConstructorInfo ctor = typeof(TMiddleware).GetConstructors().FirstOrDefault();
if (ctor == null)
{
throw new ArgumentException(typeof(TMiddleware) + " has no acceptable constructor");
}
MiddlewareDescriptor desc = new MiddlewareDescriptor
{
Instance = null,
MiddlewareType = typeof(TMiddleware),
ConstructorParameters = ctor.GetParameters().Select(x => x.ParameterType).ToArray()
};
Descriptors.Add(desc);
}
