来自 openfeign 和 Observable 的 @FeignClient 导致

Question

我有一个带有以下假客户的项目

@FeignClient(name = "name", url = "${tokenService}")

public interface TokenService {

    @RequestMapping(path = "/SLJsonWebTokenWrapper/token/wrap", method = RequestMethod.POST,

        consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)

    Observable<Token> getToken(@RequestHeader("externalSystemCode") String systemCode,

                           @RequestBody TokenRequest tokenRequest);

}

和以下依赖

org.springframework.cloud:spring-cloud-starter-feign

一切正常。当我将项目更新为 Spring Boot 2（并使用org.springframework.cloud:spring-cloud-starter-openfeign）时，对此服务的请求因异常而失败

c.f.j.d.e.InvalidDefinitionException: Cannot construct instance of 

`rx.Observable` (no Creators, like default construct, exist): cannot 

deserialize from Object value (no delegate- or property-based Creator)

 at [Source: (ByteArrayInputStream); line: 1, column: 2]

at c.f.j.d.e.InvalidDefinitionException.from(InvalidDefinitionException.java:67)

at c.f.j.d.DeserializationContext.reportBadDefinition(DeserializationContext.java:1452)

at c.f.j.d.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1028)

at c.f.j.d.d.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1297)

at c.f.j.d.d.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:326)

at c.f.j.d.d.BeanDeserializer.deserialize(BeanDeserializer.java:159)

at c.f.j.d.ObjectMapper._readMapAndClose(ObjectMapper.java:4013)

at c.f.j.d.ObjectMapper.readValue(ObjectMapper.java:3084)

... 1 frames excluded

... 99 common frames omitted

Wrapped by: o.s.h.c.HttpMessageConversionException: Type definition 

error: [simple type, class rx.Observable]; nested exception is 

com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot 

construct instance of `rx.Observable` (no Creators, like default 

construct, exist): cannot deserialize from Object value (no delegate- 

or property-based Creator)

我该如何解决？

PS 这个问题类似于Spring cloud netflix 和 HystrixObservable --> JsonMappingException，虽然没有答案

Answer 1

添加此选项解决了我的问题feign.hystrix.enabled:&nbsp;true

Answer 2

当您将 Feign 依赖项更改为：<groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId><version>2.1.0.RELEASE</version>您的 Feign 客户端的注释也将更改为例如：@FeignClient(name = "your-service-name", configuration = FeignConfig.class)