spring-boot Autowired DiscoveryClient RestTemplate UnknownHostException

Question

我正在使用弹簧靴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>

编辑

我正在使用Brixton.RC1来获得我的Spring云依赖项

<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>

我的应用程序使用以下注释进行设置:

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

我有一个服务的休息控制器:

@RestController
public class MyController {

    @Autowired
    private MyService myService;

在我的服务中,我正在尝试使用自动装配的休息模板来呼叫另一个尤里卡注册的服务.

@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'
• 获得具有正确主机和端口的有效响应

但自动装配的RestTemplate会抛出UnknownHostException.

Answer 1

的回答是,你需要创建一个@Loadbalanced RestTemplate为RC1的.

@Configuration
public class MyConfiguration {

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