How do you integrate Spring Boot with Prometheus for monitoring?

Table of Contents

• Introduction
• Steps to Integrate Prometheus with Spring Boot
  • 1. Add Dependencies to Your Spring Boot Application
    • Add Dependencies in pom.xml (Maven)
    • Add Dependencies in build.gradle (Gradle)
  • 2. Configure Spring Boot Actuator and Prometheus
    • Configure application.properties or application.yml
      • application.properties
      • application.yml
  • 3. Expose Metrics from Spring Boot Application
    • Example: Accessing Prometheus Metrics
  • 4. Set Up Prometheus to Scrape Spring Boot Metrics
    • Configure prometheus.yml
  • 5. Set Up Grafana for Visualization
    • Install Grafana
    • Add Prometheus Data Source
    • Create Dashboards
  • 6. Monitor Your Application
• Conclusion

Introduction

Prometheus is a widely used open-source monitoring and alerting toolkit designed for reliability and scalability. When integrated with Spring Boot, Prometheus can monitor various metrics such as application performance, request handling, and resource usage. This integration enables developers and operations teams to track the health and performance of Spring Boot applications in real-time. In this guide, we will show you how to integrate Prometheus with Spring Boot to expose metrics, collect data, and visualize it using Grafana.

Steps to Integrate Prometheus with Spring Boot

1. Add Dependencies to Your Spring Boot Application

To enable Prometheus monitoring in your Spring Boot application, you need to include the spring-boot-starter-actuator and micrometer-registry-prometheus dependencies in your project.

Add Dependencies in pom.xml (Maven)

Add Dependencies in build.gradle (Gradle)

These dependencies enable the Spring Boot Actuator, which exposes various system metrics, and integrate Prometheus to scrape those metrics.

2. Configure Spring Boot Actuator and Prometheus

Once the dependencies are added, you need to configure the application to expose Prometheus-compatible metrics.

Configure application.properties or application.yml

Add the following configuration to enable the Prometheus endpoint.

application.properties

application.yml

This configuration ensures that Prometheus metrics are exposed at the /actuator/prometheus endpoint of your Spring Boot application.

3. Expose Metrics from Spring Boot Application

Spring Boot Actuator provides multiple built-in metrics, such as memory usage, system health, HTTP request counts, and more. By default, these metrics are exposed at the /actuator/metrics endpoint.

Example: Accessing Prometheus Metrics

Once you have the above configuration, your application will expose Prometheus metrics at the following URL:

Accessing this URL will provide raw metric data in the Prometheus format, which Prometheus can scrape.

4. Set Up Prometheus to Scrape Spring Boot Metrics

To collect metrics from your Spring Boot application, you need to configure Prometheus to scrape the metrics exposed by your Spring Boot application.

Configure prometheus.yml

Add the following configuration to the Prometheus prometheus.yml configuration file.

In this configuration:

• job_name: Defines the name of the job (Spring Boot app).
• metrics_path: The path where the metrics are exposed (/actuator/prometheus).
• targets: The target URLs from which Prometheus will scrape metrics (your Spring Boot application is running on localhost:8080).

5. Set Up Grafana for Visualization

Grafana is a popular open-source platform for visualizing time-series data, including metrics from Prometheus. To visualize your Spring Boot metrics in Grafana:

Install Grafana

1. Download and install Grafana from the official website.
2. Once installed, open Grafana in a web browser (usually at http://localhost:3000).

Add Prometheus Data Source

1. In Grafana, navigate to Configuration -> Data Sources.
2. Add a new data source and select Prometheus.
3. Configure the Prometheus URL (e.g., http://localhost:9090).
4. Save and test the connection to Prometheus.

Create Dashboards

Once Prometheus is added as a data source, you can create dashboards in Grafana to visualize your Spring Boot metrics. Grafana provides various pre-built dashboards for Prometheus, or you can build custom dashboards to display metrics like CPU usage, HTTP request count, response times, etc.

6. Monitor Your Application

With Spring Boot, Prometheus, and Grafana configured, you can now monitor your Spring Boot application's performance and health. Prometheus collects the metrics, and Grafana helps you visualize them in a meaningful way, making it easier to detect anomalies, track resource usage, and ensure the health of your application.

Conclusion

Integrating Prometheus with Spring Boot is a straightforward process that allows you to monitor your application's performance and health effectively. By exposing Prometheus metrics through Spring Boot Actuator, configuring Prometheus to scrape these metrics, and visualizing them in Grafana, you can gain valuable insights into your application’s behavior. This integration provides a robust monitoring solution that helps in identifying potential issues, optimizing performance, and ensuring the reliability of your Spring Boot application.