Spring Boot - Getting the hostname in application.properties for Spring-Kafka client Id

问题

I am working on a project with Spring-Kafka and Boot and am wanting to get the hostname in the application.properties for the property spring.kafka.consumer.client-Id so that each of my consumers can be distinguished in the server side logs should there be an issue.

Is there a way i could do that? I check on the spring boot reference guide and java.lang.System class but could not find fruitful pointers.

回答1:

Here's one way - add an EnvironmentAware bean to your config...

@SpringBootApplication
public class So43191948Application implements EnvironmentAware {

    public static void main(String[] args) throws Exception {
        ConfigurableApplicationContext context = SpringApplication.run(So43191948Application.class, args);
        @SuppressWarnings("unchecked")
        KafkaTemplate<String, String> template = context.getBean(KafkaTemplate.class);
        template.send("so43191948", "foo");
        Thread.sleep(10000);
        context.close();
    }

    @KafkaListener(topics = "so43191948")
    public void foo(String in) {
        System.out.println(in);
    }

    @Override
    public void setEnvironment(Environment environment) {
        Properties props = new Properties();
        try {
            props.setProperty("spring.kafka.consumer.client-id", InetAddress.getLocalHost().getHostName() + ".client");
            PropertiesPropertySource propertySource = new PropertiesPropertySource("myProps", props);
            if (environment instanceof StandardEnvironment) {
                ((StandardEnvironment) environment).getPropertySources().addFirst(propertySource);
            }
        }
        catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }

}

In this case, I did it in the boot app itself but it can be done in any bean.

2017-04-03 16:12:32.646  INFO 64879 --- [           main] o.a.k.clients.consumer.ConsumerConfig    
    : ConsumerConfig values: 
auto.commit.interval.ms = 5000
auto.offset.reset = earliest
bootstrap.servers = [localhost:9092]
check.crcs = true
client.id = myhost.client
...

application.properties:

spring.kafka.consumer.client-id=foo
spring.kafka.consumer.group-id=myGroup
spring.kafka.consumer.auto-offset-reset=earliest

As you can see, the client-id is overridden.

来源：https://stackoverflow.com/questions/43191948/spring-boot-getting-the-hostname-in-application-properties-for-spring-kafka-cl

标签

spring-boot

spring-kafka