/// <inheritdoc/>
/// <remarks>Commands will be loaded regardless of presence of <see cref="CommandsHandlerAttribute"/>.</remarks>
/// <exception cref="InvalidOperationException">No mapped initializer for a command was found.</exception>
public Task <IEnumerable <ICommandInstanceDescriptor> > LoadFromMethodAsync(MethodInfo method, CancellationToken cancellationToken = default)
{
List <ICommandInstanceDescriptor> results = new List <ICommandInstanceDescriptor>();
_log?.LogTrace("Loading command {Name}", method.Name);
IEnumerable <CommandAttributeBase> attributes = method.GetCustomAttributes <CommandAttributeBase>(true);
if (!attributes.Any())
{
_log?.LogWarning("Cannot initialize command from {Handler}'s method {Name} - {Attribute} missing", method.DeclaringType.FullName, method.Name, nameof(CommandAttributeBase));
return(NullTask());
}
foreach (CommandAttributeBase attribute in attributes)
{
// ensure there's a valid initializer
ICommandInitializer initializer = _initializers.GetInitializer(attribute.GetType());
if (initializer == null)
{
throw new InvalidOperationException($"No initializer found for command type {attribute.GetType().Name}");
}
// add the command
CommandInstanceDescriptor descriptor = new CommandInstanceDescriptor(attribute, method);
results.Add(new CommandInstanceDescriptor(attribute, method));
_log?.LogTrace("Command {Name} from handler {Handler} loaded", descriptor.Method.Name, descriptor.GetHandlerType().Name);
}
return(Task.FromResult <IEnumerable <ICommandInstanceDescriptor> >(results));
}
/// <summary>Gets a command initializer for the command type.</summary> /// <typeparam name="T">Type of the command.</typeparam> /// <returns>An initializer for provided command type.</returns> public static ICommandInitializer GetMappedInitializer <T>(this ICommandInitializerProvider map) where T : CommandAttributeBase => map.GetInitializer(typeof(T));