JpaSagaStore与Jackson一起无法正确存储状态

Question

在SpringBoot应用程序中，我有以下配置：

axon:
  axonserver:
    servers: "${AXON_SERVER:localhost}"
  serializer:
    general: jackson
    messages: jackson
    events: jackson

logging.level:
  org.axonframework.modelling.saga: debug

将场景缩小到最小，佐贺类的相关部分：

@Slf4j
@Saga
@ProcessingGroup("AuctionEventManager")
public class AuctionEventManagerSaga {
    @Autowired
    private transient EventScheduler eventScheduler;

    private ScheduleToken scheduleToken;
    private Instant auctionTimerStart;

    @StartSaga
    @SagaEventHandler(associationProperty = "auctionEventId")
    protected void on(final AuctionEventScheduled event) {
        this.auctionTimerStart = event.getTimerStart();

        // Cancel any pre-existing previous job, since the scheduling thread might be lost upon a crash/restart of JVM.
        if (this.scheduleToken != null) {
            this.eventScheduler.cancelSchedule(this.scheduleToken);
        }

        this.scheduleToken = this.eventScheduler.schedule(
            this.auctionTimerStart,
            AuctionEventStarted.builder()
                .auctionEventId(event.getAuctionEventId())
                .build()
        );
    }

    @EndSaga
    @SagaEventHandler(associationProperty = "auctionEventId")
    protected void on(final AuctionEventStarted event) {
        log.info(
            "[AuctionEventManagerSaga] Current state: {scheduleToken={}, auctionTimerStart={}}",
            this.scheduleToken,
            this.auctionTimerStart
        );
    }
}

@Value
@Builder
@JsonDeserialize(builder = AuctionEventStarted.AuctionEventStartedBuilder.class)
public class AuctionEventStarted {
    AuctionEventId auctionEventId;

    @JsonPOJOBuilder(withPrefix = "")
    public static final class AuctionEventStartedBuilder {}
}

2020-05-12 15:40:01.180 DEBUG 1 --- [mandProcessor-4] o.a.m.saga.repository.jpa.JpaSagaStore   : Updating saga id c8aff7f7-d47f-4616-8a96-a40044cb7e3b as {}

1-Axon如何安全地管理Jackson忽略@autowired、来自@saga类的瞬态和静态属性？我尝试在非状态属性上手动定义@jsonignore，但仍然不起作用。

2-Axon安全地将XStream配置为忽略内部类（主要是作为私有静态final实现的构建器类）？

提前感谢，

    @Override
    public Class<AuctionEventManagerSaga> handledType() {
        return AuctionEventManagerSaga.class;
    }

    @Override
    public void serialize(
        final AuctionEventManagerSaga value,
        final JsonGenerator gen,
        final SerializerProvider serializers
    ) throws IOException {
        gen.writeStartObject();
        gen.writeObjectField("scheduleToken", value.eventScheduler);
        gen.writeObjectField("auctionTimerStart", value.auctionTimerStart);
        gen.writeEndObject();
    }

2020-05-12 16:20:01.322 DEBUG 1 --- [mandProcessor-0] o.a.m.saga.repository.jpa.JpaSagaStore   : Storing saga id c4b5d94c-7251-40a5-accf-332768b1cacd as {"delegatee":null,"unwrappingSerializer":false}

2020-05-12 17:08:06.495 DEBUG 1 --- [ault-executor-0] o.a.a.c.command.AxonServerCommandBus     : Received command response [message_identifier: "79631ffb-9a87-4224-bed3-a957730dced7"
error_code: "AXONIQ-4002"
error_message {
  message: "No converter available\n---- Debugging information ----\nmessage             : No converter available\ntype                : jdk.internal.misc.InnocuousThread\nconverter           : com.thoughtworks.xstream.converters.reflection.ReflectionConverter\nmessage[1]          : Unable to make field private static final jdk.internal.misc.Unsafe jdk.internal.misc.InnocuousThread.UNSAFE accessible: module java.base does not \"opens jdk.internal.misc\" to unnamed module @7728643a\n-------------------------------"
  location: "1@600b5b87a922"
  details: "No converter available\n---- Debugging information ----\nmessage             : No converter available\ntype                : jdk.internal.misc.InnocuousThread\nconverter           : com.thoughtworks.xstream.converters.reflection.ReflectionConverter\nmessage[1]          : Unable to make field private static final jdk.internal.misc.Unsafe jdk.internal.misc.InnocuousThread.UNSAFE accessible: module java.base does not \"opens jdk.internal.misc\" to unnamed module @7728643a\n-------------------------------"
}
request_identifier: "2f7020b1-f655-4649-bbe0-d6f458b3c2f3"
]
2020-05-12 17:08:06.505  WARN 1 --- [ault-executor-0] o.a.c.gateway.DefaultCommandGateway      : Command 'ACommandClassDispatchedFromSaga' resulted in org.axonframework.commandhandling.CommandExecutionException(No converter available
---- Debugging information ----
message             : No converter available
type                : jdk.internal.misc.InnocuousThread
converter           : com.thoughtworks.xstream.converters.reflection.ReflectionConverter
message[1]          : Unable to make field private static final jdk.internal.misc.Unsafe jdk.internal.misc.InnocuousThread.UNSAFE accessible: module java.base does not "opens jdk.internal.misc" to unnamed module @7728643a
-------------------------------)

仍然没有解决这个问题的运气...

Answer 1

我在Axon系统上工作过，其中唯一使用的serializer实现也是jacksonserializer。不过请注意，这不是Axon团队推荐的。对于消息（即命令、事件和查询），使用JSON作为序列化格式非常有意义。但是，将通用的序列化程序切换到jackson意味着您必须在域逻辑（例如，您的Saga）中添加jackson的细节“以使其工作”。

不管怎样，回溯到我成功的Jackson-Serialized-Sagas用例。在本例中，我们在想要考虑的字段（实际状态）上使用了正确的JSON注释匹配，并忽略了我们不想反序列化的字段（使用transient或@jsonignore)。为什么两者在您的场景中似乎都不起作用，在这个阶段还不完全清楚。

我记得的是，被引用项目的团队非常清楚地决定反对Lombok，因为当涉及到去/序列化时，“总体上很奇怪”。因此，作为一个尝试，在Saga类中不使用任何Lombok注释/逻辑是值得的，看看在这种状态下是否可以正确地解/序列化它。

我知道这不是一个确切的答案，但我希望它能帮助你无论如何！可能值得共享发生此问题的存储库；可能也会让其他人更清楚这个问题。