Spring Boot Actuator

We can monitor and manage a spring boot application using actuators. It is a very useful feature for troubleshooting in production. This quick guide shows you:

1. How to add/enable Spring Boot Actuator to an application ?
2. How to indent the JSON output in Spring boot actuator pages ?
3. How to see detailed health statuses in /actuator/health endpoint ?

How to add/enable Spring Boot Actuator to an application ?

1. The recommended way to enable actuator is to add the spring-boot-starter-actuator dependency.

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

2. It provides a number of built-in endpoints and lets us add our own too. All endpoints should be enabled & exposed to be available. So 2 steps. But by default all endpoints other than shutdown are enabled. But only health endpoint is exposed by default. In other words, only /actuator/health is available by default.

So if we want info and metrics endpoints to be available then we need to expose them by adding a property to application.properties

#application.properties
management.endpoints.web.exposure.include=info, metrics

#application.yml
management:
  endpoints:
    web:
      exposure:
        include: info, metrics

We can view the list of all available actuator endpoints under http://localhost:8082/actuator

If you need to expose all the actuator endpoints use the wildcard character “*”.

# For application.properties
management.endpoints.web.exposure.include=*

#For application.yml
management:
  endpoints:
    web:
      exposure:
        include: "*"

Some of the commonly used actuator endpoints are provided below.

Endpoint	Description
actuator/beans	Displays a complete list of all the available spring beans in your application.
actuator/health	Shows application health information.
actuator/info	Displays arbitrary application info.
actuator/metrics	Shows metrics information
actuator/scheduledtasks	Displays the scheduled tasks in your application.

How to indent the JSON output in Spring boot actuator pages ?

To indent the json output in spring boot actuator health or info pages add the below property to application.properties

#application.properties
spring.jackson.serialization.INDENT_OUTPUT = true

#application.yml
spring:
  jackson:
    serialization:
      INDENT_OUTPUT: true

How to enable showing detailed health status in /actuator/health endpoint ?

By default the /actuator/health endpoint will only show the summarized health status.

{
  "status" : "UP"
}

If we want to see the detailed health information in /actuator/health endpoint, we need to add the below property to application.properties

#application.properties
management.endpoint.health.show-details = always

#application.yml
management:
  endpoint:
    health:
      show-details: always