Spring Boot custom health indicator not showing up

Question

I believe followed almost all tutorials on the Internet and read many SO answers and still I'm stuck.

1. A simple health check

@Component
public class HealthCheck implements HealthIndicator {

    @Override
    public Health health() {
        return Health.up().build();
    }

}

2. Application.yaml is configured to show all details:

management.endpoints.web.exposure.include: "*"
management.endpoint.health.show-details: ALWAYS

3. Spring-boot-actuator included as dependency:

    implementation 'org.springframework.boot:spring-boot-starter-actuator'
    implementation 'org.springframework.boot:spring-boot-starter-web'

4. Spring boot of recent release:

id 'org.springframework.boot' version '2.2.0.RELEASE'

5. Main application class is annotated with @SpringBootApplication (which implicitly brings @ComponentScan).

@SpringBootApplication
public class PaymentServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(PaymentServiceApplication.class, args);
    }

}

My custom health check has to test for Apache Kafka, but I skipped the details for brevity. Still, invoking /actuator/health endpoint I get the same default result:

{
    "status": "UP",
    "components": {
        "diskSpace": {
            "status": "UP",
            "details": {
                "total": 250685575168,
                "free": 99168997376,
                "threshold": 10485760
            }
        },
        "ping": {
            "status": "UP"
        }
    }
}

Is there anything I may have missed?

Affluent

i tried it and the health endpoint is used. Could you make a system.out. there and try it again... if there is something in the console. – Sloat

Verify the component is actually configured as a spring bean. Just annotating as @Component does not guarantee it becomes a bean if there's no component scan for it. – Chromoplast

@Compass, I've updated the question. The main class is annotated with @SpringBootApplication, which enables component scan. – Affluent

Your HealthIndicator class doesn't add any extra information. – Blowbyblow

add a name to your component like @Component("healtCheck"). – Transformism

Answer 1

I found the solution, but am not sure about the cause. The class was indeed not registered as bean, and surprisingly, adding explicitly base packages attribute helped:

@SpringBootApplication(scanBasePackages="com.example.*")

Interesting that there was no need to do the above in a different project.

Affluent

The default ComponentScan will scan based on the Spring Boot Application's package path, and its subdirectories, but not anything above it hierarchically. Depending on your package arrangement this is a very likely cause, i.e. if you have a sub-application. – Chromoplast

Answer 2

This is solved by adding this code:

management:
  endpoint:
    health:
      show-details: always

However, it creates another problem. When calling /actuator/health endpoint, you see all the details which is problematic for me. What I want to achieve is to see only statuses for both endpoints.

Anthroposophy

you can expose only specific endpoints by adding property management.endpoints.web.exposure.include=endpoint1,endpoint2 where endpoint1 and endpoint2 contains a list of endpoints to expose with a commas between them. see here – Amaryllis

Answer 3

Interestingly the base package for the HealthIndicator is not recognized by the application container instead of declaring the class as @component Stereotype.

Fix for the issue- declare base package of HealthIndicator in Main Spring boot application class: @SpringBootApplication (scanBasePackages = "basepackage for your class HealthCheck") public class PaymentServiceApplication {

public static void main(String[] args) {
    SpringApplication.run(PaymentServiceApplication.class, args);
}

}

EDIT : NOTE- The above declaration of base package="" is not main spring boot class is not necessary.

You must stop the SERVER and then clean build the maven application and RESTART the server and re-run the application

You can now run find your custom health endpoint.

Eastman

Answer 4

I encounter issue too, what I miss is

management:
  endpoint:
    health:
      show-details: always

Tweed

Answer 5

Instead of using

@SpringBootApplication(scanBasePackages="com.example.*")

You can instead define your packages to scan

@ComponentScan(basePackages = {"com.example", "com.other"}

I will note I tested using scanBasepackages as described in the top answer and that doesn't seem to work if you also have the @ComponentScan defined.

Salesclerk

Answer 6

If you have packages structure like:

com.example.health.MyHealthIndicator
com.example.myapp.MyApp (SpringApplication.run() is here)

then MyHealthIndicator will not be treated as component. In this case in MyApp you should add scanBasePackages

@SpringBootApplication(scanBasePackages="com.example.*")
public class MyApp { ... }

BUT if you put your component inside package where application is, then scanBasePackages is not needed:

com.example.myapp.health.MyHealthIndicator
com.example.myapp.MyApp

Spring will automatically find all components inside com.example.myapp.* packages. And it will not search outside of this package, unless you ask him to do so via scanBasePackages parameter.

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