private static async Task <HandlerResponse> InvokeActionAsyncCore(CommandHandlerContext context, CancellationToken cancellationToken)
{
Contract.Requires(context != null);
Contract.Requires(context.Descriptor != null);
CommandHandlerDescriptor handlerDescriptor = context.Descriptor;
try
{
object result = await handlerDescriptor.ExecuteAsync(context, cancellationToken);
// This is cached in a local for performance reasons. ReturnType is a virtual property on CommandHandlerDescriptor,
// or else we'd want to cache this as part of that class.
bool isDeclaredTypeHandlerResult = typeof(ICommandHandlerResult).IsAssignableFrom(handlerDescriptor.ReturnType);
if (result == null && isDeclaredTypeHandlerResult)
{
// If the return type of the action descriptor is IHandlerResult, it's not valid to return null
throw Error.InvalidOperation(Resources.DefaultHandlerInvoker_NullHandlerResult);
}
if (isDeclaredTypeHandlerResult || handlerDescriptor.ReturnType == typeof(object))
{
ICommandHandlerResult actionResult = result as ICommandHandlerResult;
if (actionResult == null && isDeclaredTypeHandlerResult)
{
// If the return type of the action descriptor is IHandlerResult, it's not valid to return an
// object that doesn't implement IHandlerResult
throw Error.InvalidOperation(Resources.DefaultHandlerInvoker_InvalidHandlerResult, result.GetType());
}
if (actionResult != null)
{
HandlerResponse response = await actionResult.ExecuteAsync(cancellationToken);
if (response == null)
{
throw Error.InvalidOperation(Resources.DefaultHandlerInvoker_NullHandlerResponse);
}
HandlerResponse.EnsureResponseHasRequest(response, context.Request);
return(response);
}
}
// This is a non-IHandlerResult, so run the converter
return(handlerDescriptor.ResultConverter.Convert(context, result));
}
catch (HandlerResponseException handlerResponseException)
{
HandlerResponse response = handlerResponseException.Response;
HandlerResponse.EnsureResponseHasRequest(response, context.Request);
return(response);
}
}
private static async Task <HandlerResponse> HandleAsyncCore(IExceptionHandler handler, ExceptionHandlerContext context, CancellationToken cancellationToken)
{
Contract.Assert(handler != null);
Contract.Assert(context != null);
await handler.HandleAsync(context, cancellationToken);
ICommandHandlerResult result = context.Result;
if (result == null)
{
return(null);
}
HandlerResponse response = await result.ExecuteAsync(cancellationToken);
if (response == null)
{
throw Error.ArgumentNull(Resources.TypeMethodMustNotReturnNull, typeof(ICommandHandlerResult).Name, "ExecuteAsync");
}
return(response);
}