using System; using System.Linq; using System.Reflection; using System.Threading.Tasks; using NLog; using NzbDrone.Common.Composition; using NzbDrone.Common.EnsureThat; using NzbDrone.Common.Serializer; namespace NzbDrone.Common.Messaging { [Singleton] public class MessageAggregator : IMessageAggregator { private readonly Logger _logger; private readonly IServiceFactory _serviceFactory; public MessageAggregator(Logger logger, IServiceFactory serviceFactory) { _logger = logger; _serviceFactory = serviceFactory; } public void PublishEvent(TEvent @event) where TEvent : class ,IEvent { Ensure.That(() => @event).IsNotNull(); var eventName = GetEventName(@event.GetType()); _logger.Trace("Publishing {0}", eventName); //call synchronous handlers first. foreach (var handler in _serviceFactory.BuildAll>()) { try { _logger.Debug("{0} -> {1}", eventName, handler.GetType().Name); handler.Handle(@event); _logger.Debug("{0} <- {1}", eventName, handler.GetType().Name); } catch (Exception e) { _logger.ErrorException(string.Format("{0} failed while processing [{1}]", handler.GetType().Name, eventName), e); } } foreach (var handler in _serviceFactory.BuildAll>()) { var handlerLocal = handler; Task.Factory.StartNew(() => { _logger.Debug("{0} ~> {1}", eventName, handlerLocal.GetType().Name); handlerLocal.HandleAsync(@event); _logger.Debug("{0} <~ {1}", eventName, handlerLocal.GetType().Name); }); } } private static string GetEventName(Type eventType) { if (!eventType.IsGenericType) { return eventType.Name; } return string.Format("{0}<{1}>", eventType.Name.Remove(eventType.Name.IndexOf('`')), eventType.GetGenericArguments()[0].Name); } public void PublishCommand(TCommand command) where TCommand : class, ICommand { Ensure.That(() => command).IsNotNull(); var handlerContract = typeof(IExecute<>).MakeGenericType(command.GetType()); _logger.Trace("Publishing {0}", command.GetType().Name); var handler = _serviceFactory.Build(handlerContract); _logger.Debug("{0} -> {1}", command.GetType().Name, handler.GetType().Name); try { handlerContract.GetMethod("Execute").Invoke(handler, new object[] { command }); PublishEvent(new CommandCompletedEvent(command)); } catch (TargetInvocationException e) { PublishEvent(new CommandFailedEvent(command, e)); if (e.InnerException != null) { throw e.InnerException; } throw; } finally { PublishEvent(new CommandExecutedEvent(command)); } _logger.Debug("{0} <- {1}", command.GetType().Name, handler.GetType().Name); } public void PublishCommand(string commandTypeName) { var commandType = _serviceFactory.GetImplementations(typeof(ICommand)) .Single(c => c.FullName.Equals(commandTypeName, StringComparison.InvariantCultureIgnoreCase)); //json.net is better at creating objects var command = Json.Deserialize("{}", commandType); PublishCommand((ICommand)command); } } }