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Ribbon with Spring Cloud and Eureka: java.lang.IllegalStateException: No instances available for Samarths-MacBook-Pro.local

由 馋奶兔 提交于 2019-12-04 01:18:29

The RestTemplate you autowired is already connected to Ribbon. So you do a lookup by hand and then RestTemplate is trying to lookup the hostname passed in to ribbon. You have two options: 1) Don't use the netflix DiscoveryClient and pass the serviceId as a logical hostname to ribbon (http://TEST/myservice), 2) Don't use the autowired RestTemplate, create a new one for your class. My choice would be #1.

I got this working. The only change I had to make was in the way I was using RestTemplate api.

Error Code:

@Autowired
RestTemplate restTemplate;

@RequestMapping(value = "/",method = RequestMethod.GET)
String consumer(){
    String baseDir = restTemplate.getForObject("TEST", String.class);

    return baseDir;
}

Working Code:

@Autowired
RestTemplate restTemplate;

@RequestMapping(value = "/",method = RequestMethod.GET)
String consumer(){
    String baseDir = restTemplate.getForObject("http://TEST", String.class);

    return baseDir;
}

Solution:

The first parameter to restTemplate.getForObject should have the format of a URL. And the domain name should be the name of the service you want to discover.

Ex: http://TEST. Here, TEST is the name of my server registered to eureka registry

The question is already answered, but I found a workaround that seems neat and fixed our problem.

First declare a new @Component class and in it create a method that returns RestTemplate:

@Component
public class RestTemplateComponentFix{

 @Autowired
 SomeConfigurationYouNeed someConfiguration;

 @LoadBalanced
 public RestTemplate getRestTemplate() {
       // TODO set up your restTemplate
        rt.setRequestFactory( new HttpComponentsClientHttpRequestFactory() );
        return rt;
    }

}

After that just Autowire the restTemplateComponentFix in your class and when when you need the rest template call the restTemplate() method. Something like this:

@Service
public class someClass{

    @Autowired
    RestTemplateComponentFix restTemplateComponentFix;

    public void methodUsingRestTemplate(){
        // Some code...
        RestTemplate rt = restTemplateComponentFix.getRestTemplate();
        // Some code...
    }
}

After that you can unit test with something like:

RestTemplate rt = Mockito.mock(RestTemplate.class) 
when(restTemplateComponentFix.getRestTemplate()).thenReturn(rt);
when(rt.someMethod()).thenReturn(something);
标签
spring-boot
spring-cloud
resttemplate
netflix-eureka
netflix-ribbon
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