Make sure `eventType` is not `null`.

framework/src/Volo.Abp.AspNetCore.Mvc.Dapr.EventBus/Volo/Abp/AspNetCore/Mvc/Dapr/EventBus/AbpAspNetCoreMvcDaprEventBusModule.cs

@@ -97,13 +97,21 @@ public class AbpAspNetCoreMvcDaprEventBusModule : AbpModule
         if (IsAbpDaprEventData(data))
         {
             var daprEventData = daprSerializer.Deserialize(data, typeof(AbpDaprEventData)).As<AbpDaprEventData>();
-            var eventData = daprSerializer.Deserialize(daprEventData.JsonData, distributedEventBus.GetEventType(daprEventData.Topic));
-            await distributedEventBus.TriggerHandlersAsync(distributedEventBus.GetEventType(daprEventData.Topic), eventData, daprEventData.MessageId, daprEventData.CorrelationId);
+            var eventType = distributedEventBus.GetEventType(daprEventData.Topic);
+            if (eventType != null)
+            {
+                var eventData = daprSerializer.Deserialize(daprEventData.JsonData, eventType);
+                await distributedEventBus.TriggerHandlersAsync(eventType, eventData, daprEventData.MessageId, daprEventData.CorrelationId);
+            }
         }
         else
         {
-            var eventData = daprSerializer.Deserialize(data, distributedEventBus.GetEventType(topic!));
-            await distributedEventBus.TriggerHandlersAsync(distributedEventBus.GetEventType(topic!), eventData);
+            var eventType = distributedEventBus.GetEventType(topic);
+            if (eventType != null)
+            {
+                var eventData = daprSerializer.Deserialize(data, eventType);
+                await distributedEventBus.TriggerHandlersAsync(eventType, eventData);
+            }
         }
 
         httpContext.Response.StatusCode = 200;

framework/src/Volo.Abp.EventBus.Dapr/Volo/Abp/EventBus/Dapr/DaprDistributedEventBus.cs

@@ -153,7 +153,13 @@ public class DaprDistributedEventBus : DistributedEventBusBase, ISingletonDepend
 
     public async override Task PublishFromOutboxAsync(OutgoingEventInfo outgoingEvent, OutboxConfig outboxConfig)
     {
-        await PublishToDaprAsync(outgoingEvent.EventName, Serializer.Deserialize(outgoingEvent.EventData, GetEventType(outgoingEvent.EventName)), outgoingEvent.Id, outgoingEvent.GetCorrelationId());
+        var eventType = GetEventType(outgoingEvent.EventName);
+        if (eventType == null)
+        {
+            return;
+        }
+
+        await PublishToDaprAsync(outgoingEvent.EventName, Serializer.Deserialize(outgoingEvent.EventData, eventType), outgoingEvent.Id, outgoingEvent.GetCorrelationId());
 
         using (CorrelationIdProvider.Change(outgoingEvent.GetCorrelationId()))
         {
@@ -168,21 +174,9 @@ public class DaprDistributedEventBus : DistributedEventBusBase, ISingletonDepend
 
     public async override Task PublishManyFromOutboxAsync(IEnumerable<OutgoingEventInfo> outgoingEvents, OutboxConfig outboxConfig)
     {
-        var outgoingEventArray = outgoingEvents.ToArray();
-
-        foreach (var outgoingEvent in outgoingEventArray)
+        foreach (var outgoingEvent in outgoingEvents)
         {
-            await PublishToDaprAsync(outgoingEvent.EventName, Serializer.Deserialize(outgoingEvent.EventData, GetEventType(outgoingEvent.EventName)), outgoingEvent.Id, outgoingEvent.GetCorrelationId());
-
-            using (CorrelationIdProvider.Change(outgoingEvent.GetCorrelationId()))
-            {
-                await TriggerDistributedEventSentAsync(new DistributedEventSent()
-                {
-                    Source = DistributedEventSource.Outbox,
-                    EventName = outgoingEvent.EventName,
-                    EventData = outgoingEvent.EventData
-                });
-            }
+           await PublishFromOutboxAsync(outgoingEvent, outboxConfig);
         }
     }
 
@@ -201,7 +195,7 @@ public class DaprDistributedEventBus : DistributedEventBusBase, ISingletonDepend
 
     public async override Task ProcessFromInboxAsync(IncomingEventInfo incomingEvent, InboxConfig inboxConfig)
     {
-        var eventType = EventTypes.GetOrDefault(incomingEvent.EventName);
+        var eventType = GetEventType(incomingEvent.EventName);
         if (eventType == null)
         {
             return;
@@ -243,9 +237,9 @@ public class DaprDistributedEventBus : DistributedEventBusBase, ISingletonDepend
         );
     }
 
-    public Type GetEventType(string eventName)
+    public Type? GetEventType(string eventName)
     {
-        return EventTypes.GetOrDefault(eventName)!;
+        return EventTypes.GetOrDefault(eventName);
     }
 
     protected virtual async Task PublishToDaprAsync(Type eventType, object eventData, Guid? messageId = null, string? correlationId = null)

framework/src/Volo.Abp.EventBus.Rebus/Volo/Abp/EventBus/Rebus/RebusDistributedEventBus.cs

@@ -250,7 +250,12 @@ public class RebusDistributedEventBus : DistributedEventBusBase, ISingletonDepen
         OutgoingEventInfo outgoingEvent,
         OutboxConfig outboxConfig)
     {
-        var eventType = EventTypes.GetOrDefault(outgoingEvent.EventName)!;
+        var eventType = EventTypes.GetOrDefault(outgoingEvent.EventName);
+        if (eventType == null)
+        {
+            return;
+        }
+
         var eventData = Serializer.Deserialize(outgoingEvent.EventData, eventType);
 
         var headers = new Dictionary<string, string>();

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

@@ -72,6 +72,8 @@ public class LocalDistributedEventBus : DistributedEventBusBase, ISingletonDepen
 
     public override IDisposable Subscribe(Type eventType, IEventHandlerFactory factory)
     {
+        var eventName = EventNameAttribute.GetNameOrDefault(eventType);
+        EventTypes.GetOrAdd(eventName, eventType);
         return LocalEventBus.Subscribe(eventType, factory);
     }
 
@@ -157,7 +159,12 @@ public class LocalDistributedEventBus : DistributedEventBusBase, ISingletonDepen
             EventData = outgoingEvent.EventData
         });
 
-        var eventType = EventTypes.GetOrDefault(outgoingEvent.EventName)!;
+        var eventType = EventTypes.GetOrDefault(outgoingEvent.EventName);
+        if (eventType == null)
+        {
+            return;
+        }
+
         var eventData = JsonSerializer.Deserialize(Encoding.UTF8.GetString(outgoingEvent.EventData), eventType)!;
         await LocalEventBus.PublishAsync(eventType, eventData, false);
     }