Refactor and improvements on the event bus

framework/src/Volo.Abp.Core/System/Collections/Generic/AbpCollectionExtensions.cs

@@ -37,6 +37,33 @@ namespace System.Collections.Generic
             return true;
         }
 
+        /// <summary>
+        /// Adds items to the collection which are not already in the collection.
+        /// </summary>
+        /// <param name="source">The collection</param>
+        /// <param name="items">Item to check and add</param>
+        /// <typeparam name="T">Type of the items in the collection</typeparam>
+        /// <returns>Returns the added items.</returns>
+        public static IEnumerable<T> AddIfNotContains<T>([NotNull] this ICollection<T> source, IEnumerable<T> items)
+        {
+            Check.NotNull(source, nameof(source));
+
+            var addedItems = new List<T>();
+
+            foreach (var item in items)
+            {
+                if (source.Contains(item))
+                {
+                    continue;
+                }
+
+                source.Add(item);
+                addedItems.Add(item);
+            }
+
+            return addedItems;
+        }
+
         /// <summary>
         /// Adds an item to the collection if it's not already in the collection based on the given <paramref name="predicate"/>.
         /// </summary>

framework/src/Volo.Abp.EventBus.Distributed.RabbitMQ/Volo/Abp/EventBus/Distributed/RabbitMq/RabbitMqDistributedEventBus.cs

@@ -17,15 +17,15 @@ namespace Volo.Abp.EventBus.Distributed.RabbitMq
     public class RabbitMqDistributedEventBus : EventBusBase, IDistributedEventBus, ITransientDependency
     {
         protected RabbitMqDistributedEventBusOptions Options { get; }
-        protected IChannelPool ChannelPool { get; }
+        protected IConnectionPool ConnectionPool { get; }
         protected IRabbitMqSerializer Serializer { get; }
 
         public RabbitMqDistributedEventBus(
             IOptions<RabbitMqDistributedEventBusOptions> options,
-            IChannelPool channelPool,
+            IConnectionPool connectionPool,
             IRabbitMqSerializer serializer)
         {
-            ChannelPool = channelPool;
+            ConnectionPool = connectionPool;
             Serializer = serializer;
             Options = options.Value;
         }
@@ -57,18 +57,18 @@ namespace Volo.Abp.EventBus.Distributed.RabbitMq
 
         public override Task PublishAsync(Type eventType, object eventData)
         {
-            var eventName = eventType.FullName; //TODO: Get eventname from an attribute if available
+            var eventName = EventNameAttribute.GetName(eventType);
             var body = Serializer.Serialize(eventData);
 
-            using (var channelAccessor = ChannelPool.Acquire(Guid.NewGuid().ToString()))
+            using (var channel = ConnectionPool.Get().CreateModel())
             {
                 //TODO: Other properties like durable?
-                channelAccessor.Channel.ExchangeDeclare(Options.ExchangeName, "");
+                channel.ExchangeDeclare(Options.ExchangeName, "");
                 
-                var properties = channelAccessor.Channel.CreateBasicProperties();
+                var properties = channel.CreateBasicProperties();
                 properties.DeliveryMode = 2; //persistent
 
-                channelAccessor.Channel.BasicPublish(
+                channel.BasicPublish(
                    exchange: Options.ExchangeName,
                     routingKey: eventName,
                     mandatory: true,

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

@@ -1,8 +1,11 @@
-using System;
+using Microsoft.Extensions.DependencyInjection;
+using System;
 using System.Collections.Generic;
 using System.Linq;
-using Microsoft.Extensions.DependencyInjection;
+using Volo.Abp.EventBus.Distributed;
+using Volo.Abp.EventBus.Local;
 using Volo.Abp.Modularity;
+using Volo.Abp.Reflection;
 
 namespace Volo.Abp.EventBus
 {
@@ -15,22 +18,29 @@ namespace Volo.Abp.EventBus
 
         private static void AddEventHandlers(IServiceCollection services)
         {
-            var handlers = new List<Type>();
+            var localHandlers = new List<Type>();
+            var distributedHandlers = new List<Type>();
 
             services.OnRegistred(context =>
             {
-                if (context.ImplementationType.GetInterfaces().Any(i => typeof(IEventHandler).IsAssignableFrom(i)))
+                if (ReflectionHelper.IsAssignableToGenericType(context.ImplementationType, typeof(IEventHandler<>)))
                 {
-                    handlers.Add(context.ImplementationType);
+                    localHandlers.Add(context.ImplementationType);
+                }
+                else if (ReflectionHelper.IsAssignableToGenericType(context.ImplementationType, typeof(IDistributedEventHandler<>)))
+                {
+                    distributedHandlers.Add(context.ImplementationType);
                 }
             });
 
-            services.Configure<EventBusOptions>(options =>
+            services.Configure<LocalEventBusOptions>(options =>
             {
-                foreach (var handler in handlers)
-                {
-                    options.Handlers.AddIfNotContains(handler);
-                }
+                options.Handlers.AddIfNotContains(localHandlers);
+            });
+
+            services.Configure<DistributedEventBusOptions>(options =>
+            {
+                options.Handlers.AddIfNotContains(distributedHandlers);
             });
         }
     }

framework/src/Volo.Abp.EventBus/Volo/Abp/EventBus/Distributed/LocalEventBusOptions.cs

@@ -0,0 +1,14 @@
+using Volo.Abp.Collections;
+
+namespace Volo.Abp.EventBus.Distributed
+{
+    public class DistributedEventBusOptions
+    {
+        public ITypeList<IEventHandler> Handlers { get; }
+
+        public DistributedEventBusOptions()
+        {
+            Handlers = new TypeList<IEventHandler>();
+        }
+    }
+}

framework/src/Volo.Abp.EventBus/Volo/Abp/EventBus/EventBusBase.cs

@@ -121,9 +121,7 @@ namespace Volo.Abp.EventBus.Local
                 {
                     var handlerType = eventHandlerWrapper.EventHandler.GetType();
 
-                    if (ReflectionHelper.IsAssignableToGenericType(
-                        handlerType,
-                        typeof(IEventHandler<>)))
+                    if (ReflectionHelper.IsAssignableToGenericType(handlerType, typeof(IEventHandler<>)))
                     {
                         var method = typeof(IEventHandler<>) //TODO: to a static field
                             .MakeGenericType(eventType)
@@ -134,9 +132,7 @@ namespace Volo.Abp.EventBus.Local
 
                         await (Task)method.Invoke(eventHandlerWrapper.EventHandler, new[] { eventData });
                     }
-                    else if (ReflectionHelper.IsAssignableToGenericType(
-                        handlerType,
-                        typeof(IDistributedEventHandler<>)))
+                    else if (ReflectionHelper.IsAssignableToGenericType(handlerType, typeof(IDistributedEventHandler<>)))
                     {
                         var method = typeof(IDistributedEventHandler<>) //TODO: to a static field
                             .MakeGenericType(eventType)

framework/src/Volo.Abp.EventBus/Volo/Abp/EventBus/EventName.cs

@@ -0,0 +1,39 @@
+using System;
+using System.Linq;
+using JetBrains.Annotations;
+
+namespace Volo.Abp.EventBus
+{
+    [AttributeUsage(AttributeTargets.Class)]
+    public class EventNameAttribute : Attribute, IEventNameProvider
+    {
+        public string Name { get; }
+
+        public EventNameAttribute([NotNull] string name)
+        {
+            Name = Check.NotNullOrWhiteSpace(name, nameof(name));
+        }
+
+        public static string GetName<TEvent>()
+        {
+            return GetName(typeof(TEvent));
+        }
+
+        public static string GetName([NotNull] Type eventType)
+        {
+            Check.NotNull(eventType, nameof(eventType));
+
+            return eventType
+                       .GetCustomAttributes(true)
+                       .OfType<IEventNameProvider>()
+                       .FirstOrDefault()
+                       ?.Name
+                   ?? eventType.FullName;
+        }
+    }
+
+    public interface IEventNameProvider
+    {
+        string Name { get; }
+    }
+}

framework/src/Volo.Abp.EventBus/Volo/Abp/EventBus/Local/LocalEventBus.cs

@@ -6,8 +6,6 @@ using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
-using System.Runtime.CompilerServices;
-using System.Threading;
 using System.Threading.Tasks;
 using Volo.Abp.Collections;
 using Volo.Abp.DependencyInjection;
@@ -26,14 +24,14 @@ namespace Volo.Abp.EventBus.Local
         /// </summary>
         public ILogger<LocalEventBus> Logger { get; set; }
 
-        protected EventBusOptions Options { get; }
+        protected LocalEventBusOptions Options { get; }
 
         protected ConcurrentDictionary<Type, List<IEventHandlerFactory>> HandlerFactories { get; }
 
         protected IServiceProvider ServiceProvider { get; }
 
         public LocalEventBus(
-            IOptions<EventBusOptions> options,
+            IOptions<LocalEventBusOptions> options,
             IServiceProvider serviceProvider)
         {
             ServiceProvider = serviceProvider;

framework/src/Volo.Abp.EventBus/Volo/Abp/EventBus/Local/LocalEventBusOptions.cs

@@ -1,12 +1,12 @@
 using Volo.Abp.Collections;
 
-namespace Volo.Abp.EventBus
+namespace Volo.Abp.EventBus.Local
 {
-    public class EventBusOptions
+    public class LocalEventBusOptions
     {
         public ITypeList<IEventHandler> Handlers { get; }
 
-        public EventBusOptions()
+        public LocalEventBusOptions()
         {
             Handlers = new TypeList<IEventHandler>();
         }