15.5 Summary

• Spring Boot Actuator provides several endpoints, both as HTTP and JMX MBeans, that let you peek into the inner workings of a Spring Boot application.
• Most Actuator endpoints are disabled by default but can be selectively exposed by setting management.endpoints.web.exposure.include and management.endpoints.web.exposure.exclude.
• Some endpoints, such as the /loggers and /env endpoints, allow for write operations to change a running application’s configuration on the fly.
• Details regarding an application’s build and Git commit can be exposed in the /info endpoint.
• An application’s health can be influenced by a custom health indicator, tracking the health of an externally integrated application.
• Custom application metrics can be registered through Micrometer, which affords Spring Boot applications instant integration with several popular metrics engines such as Datadog, New Relic, and Prometheus.
• Actuator web endpoints can be secured using Spring Security, much like any other endpoint in a Spring application.