Health endpoint customization in Spring Boot - Mini Project: Build & Apply

Health Endpoint Customization in Spring Boot

📖 Scenario: You are building a simple Spring Boot application that needs a custom health check endpoint. This endpoint will tell if the application is healthy based on a custom condition.

🎯 Goal: Create a Spring Boot application with a custom health indicator that reports the health status as 'UP' or 'DOWN' based on a simple condition.

📋 What You'll Learn

Create a class that implements HealthIndicator

Add a boolean variable serviceUp to represent service status

Implement the health() method to return Health.up() or Health.down() based on serviceUp

Register the custom health indicator as a Spring bean

💡 Why This Matters

🌍 Real World

Custom health endpoints help monitor application status in production environments, enabling better reliability and alerting.

💼 Career

Understanding how to customize Spring Boot actuator endpoints is valuable for backend developers working on microservices and cloud-native applications.

1

Create the Custom Health Indicator Class

Create a class called CustomHealthIndicator that implements HealthIndicator interface.

Spring Boot

// Your code here to create class CustomHealthIndicator implementing HealthIndicator

Need a hint?

Start by importing Health and HealthIndicator. Then create a public class CustomHealthIndicator that implements HealthIndicator. Implement the health() method to return Health.up().build().

2

Add a Service Status Variable

Inside CustomHealthIndicator, add a private boolean variable called serviceUp and set it to true.

Spring Boot

import org.springframework.boot.actuate.health.Health;
import org.springframework.boot.actuate.health.HealthIndicator;

public class CustomHealthIndicator implements HealthIndicator {

    // Add private boolean serviceUp set to true

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

Need a hint?

Declare a private boolean variable named serviceUp and initialize it to true inside the class but outside any method.

3

Implement Conditional Health Logic

Modify the health() method to return Health.up().build() if serviceUp is true, otherwise return Health.down().build().

Spring Boot

import org.springframework.boot.actuate.health.Health;
import org.springframework.boot.actuate.health.HealthIndicator;

public class CustomHealthIndicator implements HealthIndicator {

    private boolean serviceUp = true;

    @Override
    public Health health() {
        // Return Health.up() if serviceUp is true, else Health.down()
        // Your code here
    }
}

Need a hint?

Use an if statement inside the health() method to check serviceUp. Return Health.up().build() if true, else Health.down().build().

4

Register the Custom Health Indicator as a Bean

Create a Spring configuration class called HealthConfig with a method annotated with @Bean that returns a new instance of CustomHealthIndicator.

Spring Boot

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

// Create HealthConfig class with @Configuration
// Add a @Bean method that returns new CustomHealthIndicator

// Your code here

Need a hint?

Create a class annotated with @Configuration. Inside it, add a method annotated with @Bean that returns a new CustomHealthIndicator instance.