/// <summary>
/// Adds the action with the given type to the collection.
/// </summary>
/// <param name="actionType">The type of the action.</param>
/// <param name="priority">The priority of the action. Actions with a lower value will be executed first. Note that this only affects actions which are independent from each other.</param>
public void AddAction(Type actionType, int priority = 0)
{
var actionInfo = ActionActivator.GetActionInfo(actionType);
var indexToInsert = _actions.Count;
for (int i = _actions.Count - 1; i >= 0; i--)
{
if (_actions[i].Priority <= priority)
{
break;
}
indexToInsert = i;
}
_actions.Insert(indexToInsert, new ActionCollectionEntry(actionInfo, priority));
}
public async Task ExecuteAsync(T context)
{
// Check whether the target wants to be able to trace which actions were executed on it
var trace = context is IActionTracingContainer atc ? atc.ActionTrace : null;
try
{
trace?.AddEvent(ActionTraceEvent.Begin, ToString());
foreach (var curItem in _items)
{
if (curItem == null)
{
continue;
}
// Build the action-identifier for tracing
var actionIdentifier = trace == null
? null
: curItem.ActionContext.Name + (curItem.ActionContext.Description == null ? null : $"({curItem.ActionContext.Description})");
try
{
trace?.AddEvent(ActionTraceEvent.Begin, actionIdentifier);
IAction <T> instance = null;
try
{
// Create the actual instance of the action
instance = (IAction <T>)ActionActivator.CreateInstance(
curItem.ActionInfo,
curItem.ServiceProvider,
curItem.ExportProvider);
await instance.ExecuteAsync(context, _cancellationToken);
}
finally
{
try
{
if (instance is IDisposable d)
{
d.Dispose();
}
#if (NETSTANDARD2_1 || NET)
if (instance is IAsyncDisposable ad)
{
await ad.DisposeAsync();
}
#endif
}
catch (Exception ex)
{
throw new ActionException($"An unexpected exception occured during disposing action of type \"{instance.GetType().FullName}\".", ex, curItem.ActionInfo);
}
}
// Add all exports to the global export-provider when the action finished successfully
// -> If the action would throw an exception we don't want to add already exported objects to it
foreach (var curExport in curItem.ActionContext.ExportProvider)
{
if (!curItem.ExportProvider.TryExport(curExport.Type, curExport.Name, curExport.Value))
{
throw new InvalidOperationException($"An object of type \"{curExport.Type.FullName}\" with name \"{curExport.Name}\" was already exported.");
}
}
trace?.AddEvent(ActionTraceEvent.End, actionIdentifier);
}
catch (Exception ex)
{
trace?.AddEvent(ActionTraceEvent.UnexpectedEnd, actionIdentifier, ex);
if (ex is ActionException)
{
throw;
}
}
}
trace?.AddEvent(ActionTraceEvent.End, ToString());
}
catch (Exception ex)
{
trace?.AddEvent(ActionTraceEvent.UnexpectedEnd, ToString(), ex);
if (ex is ActionException)
{
throw;
}
}
}