private static void CreateActionDescriptors(TypeInfo commandHandler, HandlerMethodsMapping methodsMapping)
{
var commandHandlerDescriptor = new HandlerParentObjectDescriptor(commandHandler);
var actionHandlers = GetHandlerForCommandHandler(commandHandler);
foreach (var actionHandler in actionHandlers)
{
var(commandType, descriptor) = CreateActionDescriptor(actionHandler, commandHandlerDescriptor);
commandHandlerDescriptor.AddActionDescriptor(descriptor);
methodsMapping.Add(commandType, descriptor);
}
}
public HandlerMethodDescriptor(Type commandType, MethodInfo action, HandlerParentObjectDescriptor handlerParentObjectDescriptor)
{
Action = action;
CommandType = commandType;
HandlerParentObjectDescriptor = handlerParentObjectDescriptor;
}
private static (Type, HandlerMethodDescriptor) CreateActionDescriptor(MethodInfo method, HandlerParentObjectDescriptor handlerParentObjectDescriptor)
{
var parameters = method.GetParameters();
if (parameters.Length != 1)
{
throw new InvalidOperationException("An command handler must have only one parameter, this parameter being the command");
}
if (!method.ReturnType.IsAssignableFrom(typeof(Task)))
{
throw new InvalidOperationException("An command handler must have return an ICommandActionResult");
}
var commandType = parameters.First().ParameterType;
var descriptor = new HandlerMethodDescriptor(commandType, method, handlerParentObjectDescriptor);
return(commandType, descriptor);
}