[Spring] actuator

들어가며

actuator란?

• 실행중인 스프링 부트 애플리케이션의 정보를 API 형식으로 확인할 수 있게 해주는 기능이다.
• 애플리케이션의 실행 여부, 패키지 로깅 레벨, Bean 목록, Metric(CPU, Heap, Thread 등) 등 여러 정보들을 확인할 수 있는 기능을 제공한다.

기본 예제

dependencies

dependencies {
    ...
    implementation 'org.springframework.boot:spring-boot-starter-actuator'    
}

application.properties

management.endpoint.health.show-details=always
management.endpoints.web.exposure.include=*

확인

• 애플리케이션 실행 후 아래 주소로 접속
• 요청
  • http://localhost:8080/actuator
• 응답

  {
      "_links": {
          "self": {
              "href": "http://localhost:8080/actuator",
              "templated": false
          },
          "beans": {
              "href": "http://localhost:8080/actuator/beans",
              "templated": false
          },
          "caches-cache": {
              "href": "http://localhost:8080/actuator/caches/{cache}",
              "templated": true
          },
          "caches": {
              "href": "http://localhost:8080/actuator/caches",
              "templated": false
          },
          "health": {
              "href": "http://localhost:8080/actuator/health",
              "templated": false
          },
          "health-path": {
              "href": "http://localhost:8080/actuator/health/{*path}",
              "templated": true
          },
          "info": {
              "href": "http://localhost:8080/actuator/info",
              "templated": false
          },
          "conditions": {
              "href": "http://localhost:8080/actuator/conditions",
              "templated": false
          },
          "configprops": {
              "href": "http://localhost:8080/actuator/configprops",
              "templated": false
          },
          "configprops-prefix": {
              "href": "http://localhost:8080/actuator/configprops/{prefix}",
              "templated": true
          },
          "env": {
              "href": "http://localhost:8080/actuator/env",
              "templated": false
          },
          "env-toMatch": {
              "href": "http://localhost:8080/actuator/env/{toMatch}",
              "templated": true
          },
          "loggers": {
              "href": "http://localhost:8080/actuator/loggers",
              "templated": false
          },
          "loggers-name": {
              "href": "http://localhost:8080/actuator/loggers/{name}",
              "templated": true
          },
          "heapdump": {
              "href": "http://localhost:8080/actuator/heapdump",
              "templated": false
          },
          "threaddump": {
              "href": "http://localhost:8080/actuator/threaddump",
              "templated": false
          },
          "metrics-requiredMetricName": {
              "href": "http://localhost:8080/actuator/metrics/{requiredMetricName}",
              "templated": true
          },
          "metrics": {
              "href": "http://localhost:8080/actuator/metrics",
              "templated": false
          },
          "scheduledtasks": {
              "href": "http://localhost:8080/actuator/scheduledtasks",
              "templated": false
          },
          "mappings": {
              "href": "http://localhost:8080/actuator/mappings",
              "templated": false
          }
      }
  }
  

노출 항목 지정

application.properties

management.endpoints.web.exposure.include=health, metrics

확인

• 요청
  • http://localhost:8080/actuator
• 응답

  {
      "_links": {
          "self": {
              "href": "http://localhost:8080/actuator",
              "templated": false
          },
          "health": {
              "href": "http://localhost:8080/actuator/health",
              "templated": false
          },
          "health-path": {
              "href": "http://localhost:8080/actuator/health/{*path}",
              "templated": true
          },
          "metrics-requiredMetricName": {
              "href": "http://localhost:8080/actuator/metrics/{requiredMetricName}",
              "templated": true
          },
          "metrics": {
              "href": "http://localhost:8080/actuator/metrics",
              "templated": false
          }
      }
  }
  

사용자 정의 Metrics

TransactionCurrentCountInterceptor

public class TransactionCurrentCountInterceptor implements HandlerInterceptor {
    private final Counter counter;

    public TransactionCurrentCountInterceptor(MeterRegistry meterRegistry) {
        this.counter = meterRegistry.counter("transaction.current.count");
    }

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
        counter.increment();
        return true;
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {
        counter.increment(-1d);
    }
}

WebMvcConfig

@RequiredArgsConstructor
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {
    private final MeterRegistry meterRegistry;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new TransactionCurrentCountInterceptor(meterRegistry))
            .addPathPatterns("/**")
            .excludePathPatterns("/actuator/**");
    }
}

확인

• 요청
  • http://localhost:8080/actuator/metrics/transaction.current.count
• 응답

  {
      "name": "transaction.current.count",
      "description": null,
      "baseUnit": null,
      "measurements": [
          {
              "statistic": "COUNT",
              "value": 0.0
          }
      ],
      "availableTags": []
  }
  

참고

• https://supawer0728.github.io/2018/05/12/spring-actuator/
• https://docs.spring.io/spring-boot/docs/current/reference/html/actuator.html