Spring Cloud：Hystrix在ping上未显示任何数据

Question

I'm using hystrix in my spring boot application but when i access the /hystrix-stream page there is no data. It shows only "ping: ". In my pom.xml i've got the following:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-ribbon</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-hystrix</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-hystrix-dashboard</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

I have enabled Hystrix and HystrixDashboard. Additionally i'm using ribbon in my application. The HystrixCommand looks like this:

@HystrixCommand(fallbackMethod = "defaultFallback")
public byte[] doGet() {
    return this.restTemplate.getForObject("http://myInstance/api/v3/ressource",byte[].class);
}

public byte[] defaultFallback() {
    System.out.println("Now doing fallback!");
    return null;
}

When i shut down myInstance there is no fallback called, ribbon shows me only this failure:

There was an unexpected error (type=Internal Server Error, status=500).
I/O error on POST request for "http:/myInstance/api/v3/ressource": Connection
refused; nested exception is java.net.ConnectException: Connection refused

Answer 1

Your spring boot application must enable the circuit breaker.

Like the next example:

@EnableCircuitBreaker
@SpringBootApplication
@EnableDiscoveryClient
@EnableWebMvc
public class ClientManagerApp {

    public static void main(String[] args) {
        SpringApplication.run(ClientManagerApp.class, args);
    }
}