Spring Boot Actuator metric với Prometheus và Grafana tích hợp thế nào?

Actuator + Micrometer export metric sang Prometheus → Grafana visualize.

Thêm spring-boot-starter-actuator + micrometer-registry-prometheus, rồi expose:

management:
  endpoints.web.exposure.include: health, info, prometheus
  metrics.tags.application: ${spring.application.name}

Custom metric:

@Component
class OrderMetrics {
  private final Counter orderCreated;
  OrderMetrics(MeterRegistry registry) {
    orderCreated = Counter.builder("orders.created").register(registry);
  }
  void record() { orderCreated.increment(); }
}

Prometheus: thêm job metrics_path: /actuator/prometheus, target app:8080. Built-in metric: JVM memory/GC, Tomcat threads, HikariCP pool, HTTP count/latency, cache hit. Grafana: import dashboard "Spring Boot Statistics" để có sẵn overview.