Auto register event handlers registered to IOC.

src/Volo.Abp.EventBus/Volo/Abp/EventBus/AbpEventBusModule.cs

@@ -1,13 +1,43 @@
-using Microsoft.Extensions.DependencyInjection;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Extensions.DependencyInjection;
+using Volo.Abp.EventBus.Handlers;
 using Volo.Abp.Modularity;
 
 namespace Volo.Abp.EventBus
 {
     public class AbpEventBusModule : AbpModule
     {
+        public override void PreConfigureServices(IServiceCollection services)
+        {
+            AddEventHandlers(services);
+        }
+
         public override void ConfigureServices(IServiceCollection services)
         {
             services.AddAssemblyOf<AbpEventBusModule>();
         }
+
+        private static void AddEventHandlers(IServiceCollection services)
+        {
+            var handlers = new List<Type>();
+
+            services.OnRegistred(context =>
+            {
+                if (context.ImplementationType.GetInterfaces().Any(i => typeof(IEventHandler).IsAssignableFrom(i)))
+                {
+                    handlers.Add(context.ImplementationType);
+                }
+            });
+
+            services.Configure<EventBusOptions>(options =>
+            {
+                foreach (var handler in handlers)
+                {
+                    options.Handlers.AddIfNotContains(handler);
+                }
+            });
+        }
     }
 }

src/Volo.Abp.EventBus/Volo/Abp/EventBus/EventBus.cs

@@ -8,6 +8,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
+using Microsoft.Extensions.Options;
 using Volo.Abp.DependencyInjection;
 using Volo.Abp.EventBus.Factories;
 using Volo.Abp.EventBus.Factories.Internals;
@@ -22,11 +23,6 @@ namespace Volo.Abp.EventBus
     /// </summary>
     public class EventBus : IEventBus, ISingletonDependency
     {
-        /// <summary>
-        /// Gets the default <see cref="EventBus"/> instance.
-        /// </summary>
-        public static EventBus Instance { get; } = new EventBus();
-
         /// <summary>
         /// Reference to the Logger.
         /// </summary>
@@ -37,16 +33,38 @@ namespace Volo.Abp.EventBus
         /// Key: Type of the event
         /// Value: List of handler factories
         /// </summary>
-        private readonly ConcurrentDictionary<Type, List<IEventHandlerFactory>> _handlerFactories;
+        protected ConcurrentDictionary<Type, List<IEventHandlerFactory>> HandlerFactories { get; }
 
-        /// <summary>
-        /// Creates a new <see cref="EventBus"/> instance.
-        /// Instead of creating a new instace, you can use <see cref="Instance"/> to use Global <see cref="EventBus"/>.
-        /// </summary>
-        public EventBus()
+        protected EventBusOptions Options { get; }
+
+        public EventBus(IOptions<EventBusOptions> options, IServiceProvider serviceProvider)
         {
-            _handlerFactories = new ConcurrentDictionary<Type, List<IEventHandlerFactory>>();
+            Options = options.Value;
             Logger = NullLogger<EventBus>.Instance;
+            HandlerFactories = new ConcurrentDictionary<Type, List<IEventHandlerFactory>>();
+
+            RegisterHandlersInOptions(serviceProvider);
+        }
+
+        protected virtual void RegisterHandlersInOptions(IServiceProvider serviceProvider)
+        {
+            foreach (var handler in Options.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)
+                    {
+                        Register(genericArgs[0], new IocHandlerFactory(serviceProvider, handler));
+                    }
+                }
+            }
         }
 
         /// <inheritdoc/>
@@ -416,7 +434,7 @@ namespace Volo.Abp.EventBus
         {
             var handlerFactoryList = new List<EventTypeWithEventHandlerFactories>();
 
-            foreach (var handlerFactory in _handlerFactories.Where(hf => ShouldTriggerEventForHandler(eventType, hf.Key)))
+            foreach (var handlerFactory in HandlerFactories.Where(hf => ShouldTriggerEventForHandler(eventType, hf.Key)))
             {
                 handlerFactoryList.Add(new EventTypeWithEventHandlerFactories(handlerFactory.Key, handlerFactory.Value));
             }
@@ -443,7 +461,7 @@ namespace Volo.Abp.EventBus
 
         private List<IEventHandlerFactory> GetOrCreateHandlerFactories(Type eventType)
         {
-            return _handlerFactories.GetOrAdd(eventType, (type) => new List<IEventHandlerFactory>());
+            return HandlerFactories.GetOrAdd(eventType, (type) => new List<IEventHandlerFactory>());
         }
 
         private class EventTypeWithEventHandlerFactories

src/Volo.Abp.EventBus/Volo/Abp/EventBus/EventBusOptions.cs

@@ -0,0 +1,15 @@
+using Volo.Abp.Collections;
+using Volo.Abp.EventBus.Handlers;
+
+namespace Volo.Abp.EventBus
+{
+    public class EventBusOptions
+    {
+        public ITypeList<IEventHandler> Handlers { get; }
+
+        public EventBusOptions()
+        {
+            Handlers = new TypeList<IEventHandler>();
+        }
+    }
+}

src/Volo.Abp.EventBus/Volo/Abp/EventBus/Factories/IocHandlerFactory.cs

@@ -10,18 +10,10 @@ namespace Volo.Abp.EventBus.Factories
     /// </summary>
     public class IocHandlerFactory : IEventHandlerFactory
     {
-        /// <summary>
-        /// Type of the handler.
-        /// </summary>
         public Type HandlerType { get; }
 
         private readonly IServiceProvider _iocResolver;
 
-        /// <summary>
-        /// Creates a new instance of <see cref="IocHandlerFactory"/> class.
-        /// </summary>
-        /// <param name="iocResolver"></param>
-        /// <param name="handlerType">Type of the handler</param>
         public IocHandlerFactory(IServiceProvider iocResolver, Type handlerType)
         {
             _iocResolver = iocResolver;
@@ -42,10 +34,6 @@ namespace Volo.Abp.EventBus.Factories
             return HandlerType;
         }
 
-        /// <summary>
-        /// Releases handler object using Ioc container.
-        /// </summary>
-        /// <param name="handler">Handler to be released</param>
         public void ReleaseHandler(IEventHandler handler)
         {
             //TODO: Scope!!!

test/Volo.Abp.EventBus.Tests/Volo.Abp.EventBus.Tests.csproj

@@ -13,6 +13,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <ProjectReference Include="..\..\src\Volo.Abp.Autofac\Volo.Abp.Autofac.csproj" />
     <ProjectReference Include="..\AbpTestBase\AbpTestBase.csproj" />
     <ProjectReference Include="..\..\src\Volo.Abp.Ddd\Volo.Abp.Ddd.csproj" />
     <ProjectReference Include="..\..\src\Volo.Abp.EventBus\Volo.Abp.EventBus.csproj" />

test/Volo.Abp.EventBus.Tests/Volo/Abp/EventBus/EventBusTestBase.cs

@@ -10,5 +10,10 @@ namespace Volo.Abp.EventBus
         {
             EventBus = GetRequiredService<IEventBus>();
         }
+
+        protected override void SetAbpApplicationCreationOptions(AbpApplicationCreationOptions options)
+        {
+            options.UseAutofac();
+        }
     }
 }

test/Volo.Abp.EventBus.Tests/Volo/Abp/EventBus/EventBus_DI_Services_Test.cs

@@ -0,0 +1,21 @@
+using System.Threading.Tasks;
+using Shouldly;
+using Xunit;
+
+namespace Volo.Abp.EventBus
+{
+    public class EventBus_DI_Services_Test : EventBusTestBase
+    {
+        [Fact]
+        public async Task Should_Automatically_Register_EventHandlers_From_Services()
+        {
+            EventBus.Trigger(new MySimpleEventData(1));
+            await EventBus.TriggerAsync(new MySimpleEventData(2));
+            EventBus.Trigger(new MySimpleEventData(3));
+            await EventBus.TriggerAsync(new MySimpleEventData(4));
+
+            GetRequiredService<MySimpleEventDataHandler>().TotalData.ShouldBe(10);
+            GetRequiredService<MySimpleAsyncEventDataHandler>().TotalData.ShouldBe(10);
+        }
+    }
+}

test/Volo.Abp.EventBus.Tests/Volo/Abp/EventBus/MySimpleAsyncEventDataHandler.cs

@@ -0,0 +1,17 @@
+using System.Threading.Tasks;
+using Volo.Abp.DependencyInjection;
+using Volo.Abp.EventBus.Handlers;
+
+namespace Volo.Abp.EventBus
+{
+    public class MySimpleAsyncEventDataHandler : IAsyncEventHandler<MySimpleEventData>, ISingletonDependency
+    {
+        public int TotalData { get; private set; }
+
+        public Task HandleEventAsync(MySimpleEventData eventData)
+        {
+            TotalData += eventData.Value;
+            return Task.CompletedTask;
+        }
+    }
+}

test/Volo.Abp.EventBus.Tests/Volo/Abp/EventBus/MySimpleEventDataHandler.cs

@@ -0,0 +1,15 @@
+using Volo.Abp.DependencyInjection;
+using Volo.Abp.EventBus.Handlers;
+
+namespace Volo.Abp.EventBus
+{
+    public class MySimpleEventDataHandler : IEventHandler<MySimpleEventData>, ISingletonDependency
+    {
+        public int TotalData { get; private set; }
+
+        public void HandleEvent(MySimpleEventData eventData)
+        {
+            TotalData += eventData.Value;
+        }
+    }
+}