How do you integrate Spring Boot with Actuator for monitoring?

Table of Contents

• Introduction
  • Steps to Integrate Spring Boot with Actuator
    • 1. Add Spring Boot Actuator Dependency
    • 2. Expose Actuator Endpoints
    • 3. Health Monitoring with Actuator
    • 4. Metrics Monitoring with Actuator
    • 5. Customize Exposed Endpoints
    • 6. Securing Actuator Endpoints (Optional)
    • 7. Customizing Health Checks
    • 8. Viewing and Analyzing Metrics
• Conclusion

Introduction

Spring Boot Actuator is a powerful module that helps you monitor and manage your Spring Boot application in production. It provides various built-in endpoints for checking the health, metrics, environment, and other critical aspects of your application. With Spring Boot Actuator, you can easily track the health of your application, monitor performance, and expose useful information about its status.

This guide will walk you through the process of integrating Spring Boot Actuator into your project, enabling various monitoring features, and exposing useful endpoints for management and health checks.

Steps to Integrate Spring Boot with Actuator

1. Add Spring Boot Actuator Dependency

To get started, you need to add the Spring Boot Actuator dependency to your pom.xml (Maven) or build.gradle (Gradle) file.

For Maven:

For Gradle:

2. Expose Actuator Endpoints

By default, Actuator’s management endpoints (like /health, /metrics, etc.) are not exposed to the public for security reasons. To expose these endpoints, you need to configure them in the application.properties or application.yml file.

Example (**application.properties**):

This configuration will expose the /actuator/health and /actuator/metrics endpoints. You can expose additional endpoints as needed.

3. Health Monitoring with Actuator

The /actuator/health endpoint provides a health status of your application, which is useful to monitor whether your application is functioning correctly.

• To check the health, visit the following endpoint in your browser or via curl:

  The response will look like:

  If there’s a problem with your application (e.g., database connectivity), the status will be "DOWN" with more detailed error information.

4. Metrics Monitoring with Actuator

Spring Boot Actuator also provides a /actuator/metrics endpoint that exposes various application metrics such as memory usage, garbage collection, active threads, etc. These metrics can be useful for performance monitoring.

• To view the metrics, visit the /actuator/metrics endpoint:

  Example response:

  You can retrieve specific metrics by adding the metric name to the endpoint. For example:

  This will provide information about the used JVM memory.

5. Customize Exposed Endpoints

You can customize which Actuator endpoints to expose and which to keep hidden. For example, if you don’t want to expose sensitive information like the /actuator/env or /actuator/configprops, you can modify the configuration:

6. Securing Actuator Endpoints (Optional)

In a production environment, you may want to secure your Actuator endpoints to restrict unauthorized access. Spring Security can be used to add authentication and authorization to Actuator endpoints.

Here’s an example of how you can secure the /actuator/health and /actuator/metrics endpoints:

**SecurityConfig.java**:

In this configuration, only users with the ADMIN role can access the health and metrics endpoints. You can customize it further depending on your requirements.

7. Customizing Health Checks

Spring Boot Actuator provides several built-in health indicators (like checking the database, disk space, etc.), but you can also create custom health indicators based on your needs.

Example: Custom Health Indicator for an External API

This custom health indicator checks if an external API is available and adds it to the overall health report.

8. Viewing and Analyzing Metrics

To view and analyze metrics such as memory usage, garbage collection, active threads, etc., you can use the /actuator/metrics endpoint. This data can be used to track the performance of your application.

For example:

• View memory usage:

• View garbage collection details:

You can also use monitoring tools like Prometheus, Grafana, or Micrometer to integrate these metrics into a larger monitoring system.

Conclusion

Integrating Spring Boot with Actuator for monitoring is a simple yet powerful way to ensure your application is performing as expected in production. By adding the Spring Boot Actuator dependency and exposing endpoints like /actuator/health and /actuator/metrics, you can monitor application health and gather useful metrics. You can also customize the health checks, secure endpoints, and integrate with external monitoring tools to keep a close watch on your application's performance.