EventBus
一、AbpLocalEventBusOptions,AbpDistributedEventBusOptions
IEventHandler是一个空方法,分为ILocalEventHandler<TEvent>,IDistributedEventHandler<TEvent>方法,
具有HandleEventAsync(EventType eventData))方法
保存着IEventHandler的实现类型,它通过OnRegistered遍历IServiceCollection服务的委托方法,将ILocalEventHandler<EventType>方法保存在AbpLocalEventBusOptions下列表
将IDistributedEventHandler<EventType>保存在AbpDistributedEventBusOptions下列表里
而ActionEventHandle<T> 是本地ILocalEventHandle的方法,它是 TransientDependency方法,它执行是委托方法。
二、IEventBus,它执行的是发布事件,订阅和取消订阅,EventBus是抽象方法,它的实现有NullDistributedEventBus, 这个不注入容器的
它的实现方法将Option的IEventHandler列表方法,将IEventHandle<eventType>的eventType以及EventHandlerFactory(多个实例),即从容器根据HandlerType获取IEventHandler,进行订阅在EventBus里
(1)、Local
(1)LocalBus:ISingletonDependency订阅方法:保存EventType,以及工厂方法保存在字典里protected ConcurrentDictionary<Type, List<IEventHandlerFactory>> HandlerFactories { get; }IEventHandleFactory工厂方法GetHandler(),IsInFactories(List(IEventHandlerFactory)),有以下3个>>SingleInstanceHandlerFactory:Subscribe(Type eventType, IEventHandler handler)Subscribe<TEvent>(TEvent委托,使用是的ActionEvent<TEvent>)
public IEventHandlerDisposeWrapper GetHandler() { return new EventHandlerDisposeWrapper(HandlerInstance); }
>>TransientEventHandlerFactory:
Subscribe<TEvent, THandler>()
protected virtual IEventHandler CreateHandler() { return (IEventHandler) Activator.CreateInstance(HandlerType); } public virtual IEventHandlerDisposeWrapper GetHandler() { var handler = CreateHandler(); return new EventHandlerDisposeWrapper( handler, () => (handler as IDisposable)?.Dispose() ); }
>>IocEventHandlerFactory,Option的默认Subscribe(Type eventType, IEventHandlerFactory factory)
public IEventHandlerDisposeWrapper GetHandler() { var scope = ScopeFactory.CreateScope(); return new EventHandlerDisposeWrapper( (IEventHandler) scope.ServiceProvider.GetRequiredService(HandlerType), () => scope.Dispose() ); }
将Option的handler订阅在EventBus里
protected virtual void SubscribeHandlers(ITypeList<IEventHandler> handlers) { foreach (var handler in handlers) { var interfaces = handler.GetInterfaces(); foreach (var @interface in interfaces) { if (!typeof(IEventHandler).GetTypeInfo().IsAssignableFrom(@interface)) { continue; } var genericArgs = @interface.GetGenericArguments(); if (genericArgs.Length == 1) { Subscribe(genericArgs[0], new IocEventHandlerFactory(ServiceScopeFactory, handler)); } } } }
(2)Distributed
1)LocalDistributedEventBus,它是TryRegister方法,它是SingletonDependency方法,它暴露是的服务接口是IDistributedEventBus以LocalDistributedEventBus
并没有继承EventBus抽象方法
三、Publish方法
Task PublishAsync(Type eventType, object eventData); Task PublishAsync<TEvent>(TEvent eventData) where TEvent : class;
执行ILocalEventHandler和 IDistributedEventHandler方法
每个EventType有多个List<IEventHandlerFactory> EventHandlerFactories
protected override IEnumerable<EventTypeWithEventHandlerFactories> GetHandlerFactories(Type eventType) { var handlerFactoryList = new List<EventTypeWithEventHandlerFactories>(); foreach (var handlerFactory in HandlerFactories.Where(hf => ShouldTriggerEventForHandler(eventType, hf.Key))) { handlerFactoryList.Add(new EventTypeWithEventHandlerFactories(handlerFactory.Key, handlerFactory.Value)); } return handlerFactoryList.ToArray(); }
private static bool ShouldTriggerEventForHandler(Type targetEventType, Type handlerEventType) { //Should trigger same type if (handlerEventType == targetEventType) { return true; } //Should trigger for inherited types if (handlerEventType.IsAssignableFrom(targetEventType)) { return true; } return false; }
四、RabbbitMQ