/// <summary>
/// Returns the Cadence activity type name to be used for a activity interface or
/// implementation class.
/// </summary>
/// <param name="activityType">The activity interface or implementation type.</param>
/// <param name="activityAttribute">Specifies the <see cref="ActivityAttribute"/>.</param>
/// <returns>The type name.</returns>
/// <remarks>
/// <para>
/// If <paramref name="activityAttribute"/> is passed and <see cref="ActivityAttribute.Name"/>
/// is not <c>null</c> or empty, then the name specified in the attribute is returned.
/// </para>
/// <para>
/// Otherwise, we'll return the fully qualified name of the activity interface
/// with the leadting "I" removed.
/// </para>
/// </remarks>
internal static string GetActivityTypeName(Type activityType, ActivityAttribute activityAttribute)
{
Covenant.Requires <ArgumentNullException>(activityType != null, nameof(activityType));
if (activityAttribute != null && !string.IsNullOrEmpty(activityAttribute.Name))
{
return(activityAttribute.Name);
}
if (activityType.IsClass)
{
CadenceHelper.ValidateActivityImplementation(activityType);
activityType = CadenceHelper.GetActivityInterface(activityType);
}
else
{
CadenceHelper.ValidateActivityInterface(activityType);
}
var fullName = activityType.FullName;
var name = activityType.Name;
if (name.StartsWith("I") && name != "I")
{
// We're going to strip the leading "I" from the unqualified
// type name (unless that's the only character).
fullName = fullName.Substring(0, fullName.Length - name.Length);
fullName += name.Substring(1);
}
// We need to replace the "+" characters .NET uses for nested types into
// "." so the result will be a valid C# type identifier.
return(fullName.Replace('+', '.'));
}
/// <summary>
/// Returns the activity type and method information for an activity interface and
/// an optional target method name.
/// </summary>
/// <param name="activityInterface">The target activity interface.</param>
/// <param name="methodName">
/// Optionally specifies the target method name (as specified in the <c>[ActivityMethod]</c>
/// attribiute tagging the activity method within the interface.
/// </param>
/// <returns>The activity type name for the activity interface as well as the method information and attribute.</returns>
/// <exception cref="ArgumentException">Thrown if target method does not exist.</exception>
/// <remarks>
/// <paramref name="methodName"/> is optional. When this is passed as <c>null</c>
/// or empty, the default activity method will be targeted (if any).
/// </remarks>
internal static (string ActivityTypeName, MethodInfo TargetMethod, ActivityMethodAttribute MethodAttribute) GetActivityTarget(Type activityInterface, string methodName = null)
{
Covenant.Requires <ArgumentNullException>(activityInterface != null);
CadenceHelper.ValidateActivityInterface(activityInterface);
var activityAttribute = activityInterface.GetCustomAttribute <ActivityAttribute>();
var methodAttribute = (ActivityMethodAttribute)null;
var targetMethod = (MethodInfo)null;
if (string.IsNullOrEmpty(methodName))
{
// Look for the entrypoint method with a null or empty method name.
foreach (var method in activityInterface.GetMethods())
{
methodAttribute = method.GetCustomAttribute <ActivityMethodAttribute>();
if (methodAttribute != null)
{
if (string.IsNullOrEmpty(methodAttribute.Name))
{
targetMethod = method;
break;
}
}
}
}
else
{
// Look for the entrypoint method with the matching method name.
foreach (var method in activityInterface.GetMethods())
{
methodAttribute = method.GetCustomAttribute <ActivityMethodAttribute>();
if (methodAttribute != null)
{
if (methodName == methodAttribute.Name)
{
targetMethod = method;
break;
}
}
}
}
if (targetMethod == null)
{
throw new ArgumentException($"Activity interface [{activityInterface.FullName}] does not have a method tagged by [ActivityMethod(Name = {methodName})].", nameof(activityInterface));
}
var activityTypeName = CadenceHelper.GetActivityTypeName(activityInterface, activityAttribute);
if (!string.IsNullOrEmpty(methodAttribute.Name))
{
activityTypeName += $"::{methodAttribute.Name}";
}
return(activityTypeName, targetMethod, methodAttribute);
}
