具有 List<T> 成员的 MassTransit Job Consumer 消息未反序列化

Question

我已成功设置、配置和运行 MassTransit (v8.0.3) JobConsumers 示例，现在正尝试自定义我的项目。修改后，提交作业时遇到反序列化问题：

Newtonsoft.Json.JsonSerializationException: Cannot deserialize the current JSON array (e.g. [1,2,3]) into type 'MyNamespace.Foo' because the type requires a JSON object (e.g. {"name":"value"}) to deserialize correctly.
To fix this error either change the JSON to a JSON object (e.g. {"name":"value"}) or change the deserialized type to an array or a type that implements a collection interface (e.g. ICollection, IList) like List<T> that can be deserialized from a JSON array. JsonArrayAttribute can also be added to the type to force it to deserialize from a JSON array.
Path 'foos[0]'.
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.EnsureArrayContract(JsonReader reader, Type objectType, JsonContract contract)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateList(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, Object existingValue, String id)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateList(IList list, JsonReader reader, JsonArrayContract contract, JsonProperty containerProperty, String id)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateList(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, Object existingValue, String id)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
   at Newtonsoft.Json.Serialization.JsonSerializerProxy.DeserializeInternal(JsonReader reader, Type objectType)
   at MassTransit.Serialization.JsonConverters.InterfaceProxyConverter.CachedConverter`1.MassTransit.Serialization.JsonConverters.BaseJsonConverter.IConverter.Deserialize(JsonReader reader, Type objectType, JsonSerializer serializer) in /_/src/MassTransit.Newtonsoft/Serialization/JsonConverters/InterfaceProxyConverter.cs:line 31
   at MassTransit.Serialization.JsonConverters.BaseJsonConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer) in /_/src/MassTransit.Newtonsoft/Serialization/JsonConverters/BaseJsonConverter.cs:line 15
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.DeserializeConvertable(JsonConverter converter, JsonReader reader, Type objectType, Object existingValue)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
   at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)
   at Newtonsoft.Json.JsonSerializer.Deserialize[T](JsonReader reader)
   at MassTransit.Serialization.NewtonsoftObjectDeserializer.DeserializeObject[T](Object value, T defaultValue) in /_/src/MassTransit.Newtonsoft/Serialization/NewtonsoftObjectDeserializer.cs:line 34
   at MassTransit.Serialization.BaseSerializerContext.DeserializeObject[T](Object value, T defaultValue) in /_/src/MassTransit/Serialization/EnvelopeSerializerContext.cs:line 52
   at MassTransit.JobServiceEventExtensions.GetJob[TJob](ConsumeContext`1 context) in /_/src/MassTransit/JobServiceEventExtensions.cs:line 24
   at MassTransit.JobService.FinalizeJobConsumer`1.Consume(ConsumeContext`1 context) in /_/src/MassTransit/JobService/JobService/FinalizeJobConsumer.cs:line 45
   at MassTransit.Middleware.MethodConsumerMessageFilter`2.MassTransit.IFilter<MassTransit.ConsumerConsumeContext<TConsumer,TMessage>>.Send(ConsumerConsumeContext`2 context, IPipe`1 next) in /_/src/MassTransit/Middleware/MethodConsumerMessageFilter.cs:line 27
   at MassTransit.Middleware.LastPipe`1.Send(TContext context) in /_/src/MassTransit.Abstractions/Middleware/Middleware/LastPipe.cs:line 30
   at MassTransit.Consumer.DelegateConsumerFactory`1.Send[TMessage](ConsumeContext`1 context, IPipe`1 next) in /_/src/MassTransit/Consumers/Consumer/DelegateConsumerFactory.cs:line 29
   at MassTransit.Consumer.DelegateConsumerFactory`1.Send[TMessage](ConsumeContext`1 context, IPipe`1 next) in /_/src/MassTransit/Consumers/Consumer/DelegateConsumerFactory.cs:line 39
   at MassTransit.Middleware.ConsumerMessageFilter`2.MassTransit.IFilter<MassTransit.ConsumeContext<TMessage>>.Send(ConsumeContext`1 context, IPipe`1 next) in /_/src/MassTransit/Middleware/ConsumerMessageFilter.cs:line 46

我正在使用 MassTransit.Newtonsoft 来支持 JSON，因为我在我的项目中使用它，并且升级到 MassTransit v8 时遇到问题。在这里配置：

x.UsingRabbitMq((context, cfg) =>
{
    cfg.UseNewtonsoftJsonSerializer();
    cfg.UseNewtonsoftJsonDeserializer();

    ...
}

这是我的消息定义（替换示例的 ConvertVideo），精简到最小的失败案例：

public interface ProcessFoos
{
    List<Foo> Foos { get; }
}

其中 Foo 定义为：

public class Foo
{
   public string FooID { get; set; } 
}

我正在通过以下电话从其他消费者那里开始新工作：

var foos = new List<Foo>
{
    new Foo { FooID = "foo" }
};

Response<JobSubmissionAccepted> response = await _processFoosClient.GetResponse<JobSubmissionAccepted>(new
{
    Foos = foos
});

我的工作消费者如下所示：

public class ProcessFoosJobConsumer : IJobConsumer<ProcessFoos>
{
    public async Task Run(JobContext<ProcessFoos> context)
    {
        // Never gets here due to the deserialization issue
        var processFoos = context.Job;
        ...
    }
}

根据 MassTransit 文档和我在研究时发现的所有内容，这似乎应该得到支持，我可能只是缺少一些简单的东西。

Answer 1

我只是添加了这个：

configurator.UseNewtonsoftJsonSerializer();

在现有项目中，将List<T> 属性添加到工作合同中，并且工作序列化完全没有问题。如果您在 GitHub 上有一个独立项目可以重现该问题，欢迎您在 GitHub 上创建讨论。

TL;DR：在我的机器上工作。