未知的鉴别值"MyEvent" [英] Unknown discriminator value 'MyEvent'

问题描述

在 joliver/EventStore 中使用MongoDB持久性引擎会导致错误Unknown discriminator value 'MyEvent'.仅当我尝试加载所有事件以重播this.storeEvent.Advanced.GetFrom(new DateTime(2010, 1,1))

Using the MongoDB persistance engine in joliver/EventStore causing the error Unknown discriminator value 'MyEvent'. The issue is only caused when I try to load all events for replaying the events like this.storeEvent.Advanced.GetFrom(new DateTime(2010, 1,1))

问题是由ExtensionsMethods.cs引起的

The issues is caused in ExtensionsMethods.cs

public class MyClassEvent : IDomainEvent { ... }

public static Commit ToCommit(this BsonDocument doc, IDocumentSerializer serializer)
    {
        if (doc == null)
            return null;

        var id = doc["_id"].AsBsonDocument;
        var streamId = id["StreamId"].AsGuid;
        var commitSequence = id["CommitSequence"].AsInt32;

        var events = doc["Events"].AsBsonArray.Select(e => e.AsBsonDocument["Payload"].IsBsonDocument ? BsonSerializer.Deserialize<EventMessage>(e.AsBsonDocument["Payload"].AsBsonDocument) : serializer.Deserialize<EventMessage>(e.AsBsonDocument["Payload"].AsByteArray)).ToList();
        var streamRevision = doc["Events"].AsBsonArray.Last().AsBsonDocument["StreamRevision"].AsInt32;
        return new Commit(
            streamId,
            streamRevision,
            doc["CommitId"].AsGuid,
            commitSequence,
            doc["CommitStamp"].AsDateTime,
            BsonSerializer.Deserialize<Dictionary<string, object>>(doc["Headers"].AsBsonDocument),
            events);
    }

我的配置是这样的:

 Wireup.Init()                
            .UsingMongoPersistence(connectionName, new DocumentObjectSerializer())
            .UsingBsonSerialization()    
            .UsingAsynchronousDispatcher()                                
            .PublishTo(this.container.Resolve<IPublishMessages>())
            .Build();

但是尝试了几乎所有类型的序列化器选项.

But have tried almost all kind of serializer options.

推荐答案

尝试使用BsonClassMap.RegisterClassMap方法注册对象(本身就是事件消息以及EventStore有效负载的主题).看来EventStore的mongo扩展可以很好地处理字符串有效载荷，但不能很好地处理反序列化的对象...就我而言，至少注册分类是解决问题的方法.

Try to register your objects (itself the event messages as well as the subjects of the EventStore payloads) using the BsonClassMap.RegisterClassMap method. It seems EventStore's mongo extension handles the string payloads well, but not the deserialized objects ... at least registering the classed was the solution in my case.

这篇关于未知的鉴别值"MyEvent"的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！