spring cloud config (watcher) 구현하기 3

서버를 껐다 켜지 않아도 데이타가 refresh 되는 spring cloud config!

data를 refresh 하는 방법은 수동/자동 두 가지가 있다.

 

수동 방법

actuator/refresh 호출하고 rest api 호출하면 data refresh 가 된다.

가장 기본적인 방법이지만 매번 api를 호출 해줘야 하기 때문에 귀찮은 방법.

 

(위의 방법을 사용하려면 actuator dependency 등록을 해줘야된다.)

 

자동 방법

scheduler를 사용한다.(config client watcher)

 

1. application.properties 에 configClientWatch 설정 추가

spring.cloud.config.watch.enabled=true
spring.cloud.config.watch.initialDelay=5000
spring.cloud.config.watch.delay=10000

 

2.scheduler 생성

import java.io.Closeable;
import java.util.concurrent.atomic.AtomicBoolean;

import javax.annotation.PostConstruct;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.config.client.ConfigClientStateHolder;
import org.springframework.cloud.context.refresh.ContextRefresher;
import org.springframework.context.EnvironmentAware;
import org.springframework.core.env.Environment;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;

@Service
public class ConfigClientWatchScheduler implements Closeable, EnvironmentAware {

	private final AtomicBoolean running = new AtomicBoolean(false);

	private final ContextRefresher refresher;

	private Environment environment;

	public ConfigClientWatchScheduler(ContextRefresher refresher) {
		this.refresher = refresher;
	}

	@Override
	public void setEnvironment(Environment environment) {
		this.environment = environment;
	}

	@PostConstruct
	public void start() {
		this.running.compareAndSet(false, true);
	}

	private Logger logger = LoggerFactory.getLogger(ConfigClientWatchScheduler.class);
	
	
	@Scheduled(initialDelayString = "${spring.cloud.config.watch.initialDelay}", fixedDelayString = "${spring.cloud.config.watch.delay}")
	public void watchConfigServer() {
		
		if (this.running.get()) {
		
			this.refresher.refresh();
		}
	}

	 
	@Override
	public void close() {
		this.running.compareAndSet(true, false);
	}

}

 

 

this.refresher.refresh()로 주기적으로 값을  refresh 하여 가져오게된다.

 

 

참고 사이트

https://github.com/spring-cloud/spring-cloud-config/blob/main/spring-cloud-config-client/src/main/java/org/springframework/cloud/config/client/ConfigClientWatch.java