我们刚刚升级到spring cloud stream的3.0.0版本，遇到以下问题：
当使用这样的功能样式时：

public class EventProcessor {

    private final PriceValidator priceValidator;

    @Bean
    public Function<Flux<EnrichedValidationRequest>, Flux<ValidationResult>> validate() {
        return enrichedValidationRequestFlux -> enrichedValidationRequestFlux
                .map(ProcessingContext::new)
                .flatMap(priceValidator::validateAndMap);
    }
}

application.yaml如下所示：

spring.cloud.stream:
  default-binder: kafka
  kafka:
    binder:
      brokers: ${kafka.broker.prod}
      auto-create-topics: false
  function.definition: validate

# INPUT: enrichedValidationRequests

spring.cloud.stream.bindings.validate-in-0:
  destination: ${kafka.topic.${spring.application.name}.input.enrichedValidationRequests}
  group: ${spring.application.name}.${STAGE:NOT_SET}
  consumer:
    useNativeDecoding: true

spring.cloud.stream.kafka.bindings.validate-in-0:
  consumer:
    configuration:
      key.deserializer: org.apache.kafka.common.serialization.StringDeserializer
      value.deserializer: de.pricevalidator.deserializer.EnrichedValidationRequestDeserializer

# OUTPUT: validationResults

spring.cloud.stream.bindings.validate-out-0:
  destination: validationResultsTmp
  producer:
    useNativeEncoding: true

spring.cloud.stream.kafka.bindings.validate-out-0:
  producer:
    compression.type: lz4
    messageKeyExpression: payload.offerKey
    configuration:
      key.serializer: org.apache.kafka.common.serialization.StringSerializer
      value.serializer: de.pricevalidator.serializer.ValidationResultSerializer

序列化似乎完成了两次—当我们截获kafka主题中生成的消息时，使用者只会将它们显示为json（字符串），但现在它是一个不可读的字节[]。而且，生产中的下游消费者不能再反序列化消息了。奇怪的是，输入消息的反序列化似乎工作得很好，无论我们在consumer属性中放入了什么（无论是在binder还是默认的kafka级别），我们都有一种感觉，这个bug“回来了”，但我们在代码中找不到确切的位置：https://github.com/spring-cloud/spring-cloud-stream/issues/1536
我们（丑陋的）解决方法：

@Slf4j
@Configuration
public class KafkaMessageConverterConfiguration {

    @ConditionalOnProperty(value = "spring.cloud.stream.default-binder", havingValue = "kafka")
    @Bean
    public MessageConverter validationResultConverter(BinderTypeRegistry binder, ObjectMapper objectMapper) {
        return new AbstractMessageConverter(MimeType.valueOf("application/json")) {
            @Override
            protected boolean supports(final Class<?> clazz) {
                return ValidationResult.class.isAssignableFrom(clazz);
            }

            @Override
            protected Object convertToInternal(final Object payload, final MessageHeaders headers, final Object conversionHint) {
                return payload;
            }
        };
    }
}

有没有一种“正确”的方法来设置自定义序列化程序或像以前一样获取本机编码？