public static ActionInfo GetActionInfo(Type actionType)
{
if (actionType == null)
{
throw new ArgumentNullException(nameof(actionType));
}
lock (_cachedActionInfosLock)
{
if (_cachedActionInfos.TryGetValue(actionType, out var actionInfo))
{
return(actionInfo);
}
if (!typeof(IAction <T>).IsAssignableFrom(actionType) || actionType.IsAbstract)
{
throw new InvalidOperationException($"Type \"{actionType.FullName}\" does not inherit from \"{typeof(IAction<T>).FullName}\".");
}
if (!TryGetActionConstructor(actionType, out var constructorInfo))
{
throw new InvalidOperationException($"No constructor for type \"{actionType.FullName}\" was found.");
}
var metadataAttr = actionType.GetCustomAttribute <ActionAttribute>(false);
var imports = GetTypesToImport(constructorInfo);
actionInfo = new ActionInfo(
actionType,
metadataAttr?.FriendlyName,
metadataAttr?.Description,
imports);
_cachedActionInfos.Add(actionType, actionInfo);
return(actionInfo);
}
}
public DefaultActionContext(IExportProvider globalExportProvider, ActionInfo actionInfo)
{
_globalExportProvider = globalExportProvider ?? throw new ArgumentNullException(nameof(globalExportProvider));
_actionInfo = actionInfo ?? throw new ArgumentNullException(nameof(actionInfo));
}
/// <summary>
/// Creates an instance of the action related to the given <see cref="ActionInfo"/>.
/// Required services and imports will be taken from the given <see cref="IServiceProvider"/> and <see cref="IExportProvider"/>.
/// </summary>
/// <param name="actionInfo">The related action-info of the action to create.</param>
/// <param name="serviceProvider">The service-provider used for dependency-injection.</param>
/// <param name="exportProvider">The export-provider used for dependency-injection.</param>
/// <exception cref="ArgumentNullException"></exception>
/// <exception cref="InvalidOperationException"></exception>
public static object CreateInstance(ActionInfo actionInfo, IServiceProvider serviceProvider, IExportProvider exportProvider)
{
if (actionInfo == null)
{
throw new ArgumentNullException(nameof(actionInfo));
}
if (serviceProvider == null)
{
throw new ArgumentNullException(nameof(serviceProvider));
}
if (exportProvider == null)
{
throw new ArgumentNullException(nameof(exportProvider));
}
var parameters = actionInfo.Constructor.GetParameters();
var parameterValues = new object[parameters.Length];
var parameterValuesSet = new bool[parameters.Length];
foreach (var curImport in actionInfo.Imports)
{
var importValue = exportProvider.GetExport(curImport.Type, curImport.Name);
if (importValue == null)
{
throw new InvalidOperationException(
string.Format(
"Unable to resolve import for type \"{0}\"{1} while attempting to activate \"{2}\".",
curImport.Type.FullName,
curImport.Name == null ? string.Empty : $" and name \"{curImport.Name}\"",
actionInfo.ActionType.FullName));
}
parameterValues[curImport.ConstructorIndex] = importValue;
parameterValuesSet[curImport.ConstructorIndex] = true;
}
for (int i = 0; i < parameters.Length; i++)
{
if (!parameterValuesSet[i])
{
var value = serviceProvider.GetService(parameters[i].ParameterType);
if (value == null)
{
if (!TryGetParameterDefaultValue(parameters[i], out var defaultValue))
{
throw new InvalidOperationException($"Unable to resolve service for type \"{parameters[i].ParameterType}\" while attempting to activate \"{actionInfo.ActionType.FullName}\".");
}
parameterValues[i] = defaultValue;
}
else
{
parameterValues[i] = value;
}
}
}
try
{
return(actionInfo.Constructor.Invoke(parameterValues));
}
catch (TargetInvocationException ex)
{
ExceptionDispatchInfo.Capture(ex.InnerException).Throw();
// The above line will always throw, but the compiler requires we throw explicitly.
throw;
}
}
public ActionException(string message, Exception innerException, ActionInfo actionInfo)
: base(message, innerException)
{
ActionInfo = actionInfo;
}
public ActionException(string message, ActionInfo actionInfo)
: this(message, null, actionInfo)
{
}
public ActionCollectionEntry(ActionInfo actionInfo, int priority)
{
ActionInfo = actionInfo ?? throw new ArgumentNullException(nameof(actionInfo));
Priority = priority;
}