Change FeignClient url at runtime

As a possible solution - RequestInterceptor could be introduced in order to set URL in RequestTemplate from a property defined in the RefreshScope.

To implement this approach you should do the following:

1. Define ConfigurationProperties Component in the RefreshScope

   @Component
   @RefreshScope
   @ConfigurationProperties("storeclient")
   public class StoreClientProperties {
       private String url;
       ...
   }
   

2. Specify default URL for the client in the application.yml

   storeclient
       url: https://someurl
   

3. Define RequestInterceptor that will switch URL

   @Configuration
   public class StoreClientConfiguration {
   
       @Autowired
       private StoreClientProperties storeClientProperties;
   
       @Bean
       public RequestInterceptor urlInterceptor() {
           return template -> template.insert(0, storeClientProperties.getUrl());
       }
   
   }
   

4. Use some placeholder in your FeignClient definition for the URL, because it will not be used

   @FeignClient(name = "storeClient", url = "NOT_USED")
   public interface StoreClient {
       //..
   }
   

Now storeclient.url can be refreshed and the URL defined will be used in RequestTemplate to sent http request.

A bit extended answer with RequestInterceptor:

1. application.yml

app:
  api-url: http://external.system/messages
  callback-url: http://localhost:8085/callback

2. @ConfigurationProperties

@Component
@RefreshScope
@ConfigurationProperties("app")
public class AppProperties {
    private String apiUrl;
    private String callbackUrl;
    ...
}

3. @FeignClient-s configuration

Make sure your ...ClientConfig class is not annotated with any @Component/... annotations or is found by a component scan.

public class ApiClientConfig {
    @Bean
    public RequestInterceptor requestInterceptor(AppProperties appProperties) {
        return requestTemplate -> requestTemplate.target(appProperties.getApiUrl());
    }
}

public class CallbackClientConfig {
    @Bean
    public RequestInterceptor requestInterceptor(AppProperties appProperties) {
        return requestTemplate -> requestTemplate.target(appProperties.getCallbackUrl());
    }
}

4. @FeignClient-s

@FeignClient(name = "apiClient", url = "NOT_USED", configuration = ApiClientConfig.class)
public interface ApiClient {
    ...
}

@FeignClient(name = "callbackClient", url = "NOT_USED", configuration = CallbackClientConfig.class)
public interface CallbackClient {
    ...
}