spring-boot Autowired DiscoveryClient RestTemplate UnknownHostException

时间:2016-04-06 18:05:29

标签: spring-boot spring-cloud spring-cloud-netflix

我使用的是spring boot 1.3.3

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.3.3.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

修改

我使用Brixton.RC1作为我的春天云依赖

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Brixton.RC1</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

我的应用程序设置了这些注释:

@EnableDiscoveryClient
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

我有一个带有服务的休息控制器:

@RestController
public class MyController {

    @Autowired
    private MyService myService;

在我的服务中,我尝试使用自动安装的休息模板呼叫另一个尤里卡注册服务。

@Service
public class MyServiceImpl {

    private final ParameterizedTypeReference<Answer> ANSWER = new ParameterizedTypeReference<Answer>() {};

    @Autowired
    private DiscoveryClient discoveryClient; //just here for testing

    @Autowired
    private RestTemplate restTemplate; //

    public String someCoolMethod(String input){
        log.info("Instance available? " + isInstanceAvailable());

        final RequestEntity<String> requestEntity = RequestEntity.post(URI.create("http://myotherservice/othermethod")).accept(MediaType.APPLICATION_JSON).body(input);
        final ResponseEntity<String> response = this.restTemplate.exchange(requestEntity, ANSWER);
        log.info(response);
        return response.getBody();
    }

    private Boolean isInstanceAvailable(){
        List<ServiceInstance> instances = discoveryClient.getInstances("myotherservice");
        for(ServiceInstance si : instances){
            log.info(si.getUri().toString());
        }
        return instances.size() > 0;
    }

}

我完全感到困惑,因为我在另一个项目中工作。这也是输出:

INFO http://192.168.1.10:1234
INFO Instance available? true
ERROR I/O error on POST request for "http://myotherservice/othermethod": myotherservice; nested exception is java.net.UnknownHostException: myotherservice

所以我可以看到这两项服务都在Eureka注册。 MyService能够:

  • 在Eureka注册
  • 查询Eureka的“myotherservice&#39;
  • 使用正确的主机和端口获得有效响应

但自动装配的RestTemplate正在抛出UnknownHostException。

1 个答案:

答案 0 :(得分:12)

从{1}}开始,您需要在RC1中创建@Loadbalanced RestTemplate

@Configuration
public class MyConfiguration {

    @LoadBalanced
    @Bean
    RestTemplate restTemplate() {
        return new RestTemplate();
    }
}