Actuator
引入依赖spring-boot-starter-actuator，通过endpoint来暴露HTTP或JMX来监管应用
通过http://localhost:8080/actuator，可以查看所有endpoints，eg：
/actuator/health, /actuator/info, /actuator/metrics, /actuator/loggers
/health：健康指数检查
通过management.endpoint.health.show-details=always可以显示详细的健康信息。
实现HealthIndicator接口，或继承AbstractHealthIndicator类自定义健康指标
@Component
public class CustomerHealthIndicator extends AbstractHealthIndicator {
@Override
protected void doHealthCheck(Health.Builder builder) throws Exception {
builder.up().withDetail("xxx", "xxx xxx");
}
}
/info：应用基本信息
通过META-INF/build-info.properties获得编译信息，通过git.properties获得git信息
# INFO ENDPOINT CONFIGURATION
info:
app:
name: @project.name@
description: @project.description@
version: @project.version@
encoding: @project.build.sourceEncoding@
java:
version: @java.version@
Automatic Property Expansion：扩展maven工程的properties
授权访问
通过HTTP认证保护Actuator Endpoints的安全：spring-boot-starter-security