Prometheus and Grafana with Spring Boot

This repository provides a sample Spring Boot application integrated with Prometheus for metrics collection and Grafana for visualization and monitoring. It demonstrates how to expose application metrics using Spring Boot Actuator and Micrometer, scrape them with Prometheus, and create dashboards in Grafana for observing JVM metrics, HTTP requests, and other key performance indicators.

The project includes a basic Spring Boot REST API, configuration files for Prometheus, and a Docker Compose setup to run everything locally.

Features

• Spring Boot application with Actuator and Micrometer for Prometheus metrics export.
• Prometheus configuration to scrape metrics from the Spring Boot app.
• Grafana setup with pre-configured dashboards for JVM and application metrics.
• Docker Compose for easy deployment of Prometheus and Grafana.
• Example endpoints to generate metrics (e.g., a simple "/hello" API).

Prerequisites

• Java 17 or higher (for Spring Boot 3.x).
• Maven 3.6+ (for building the Spring Boot app).
• Docker and Docker Compose (for running Prometheus and Grafana).
• Git (to clone the repository).

Installation

1. Clone the Repository

   git clone https://github.com/moshclouds/Prometheus-And-Grafana-With-Springboot.git
   cd Prometheus-And-Grafana-With-Springboot
   

2. Build the Spring Boot Application Use Maven to build the project:

   mvn clean install
   

3. Run the Spring Boot Application Start the app locally:

   mvn spring-boot:run
   

   The application will run on http://localhost:8080. Metrics will be exposed at http://localhost:8080/actuator/prometheus.

Configuration

Spring Boot Dependencies (pom.xml excerpt)

Add the following dependencies to enable Actuator and Prometheus metrics:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>io.micrometer</groupId>
        <artifactId>micrometer-registry-prometheus</artifactId>
    </dependency>
</dependencies>

Application Properties (application.yml or application.properties)

Enable the Prometheus endpoint:

management:
  endpoints:
    web:
      exposure:
        include: prometheus, health, info
  metrics:
    export:
      prometheus:
        enabled: true

Prometheus Configuration (prometheus.yml)

Configure Prometheus to scrape metrics from the Spring Boot app. Example for local setup:

global:
  scrape_interval: 15s
  evaluation_interval: 15s

scrape_configs:
  - job_name: 'spring-boot-app'
    metrics_path: '/actuator/prometheus'
    static_configs:
      - targets: ['host.docker.internal:8080']  # Use 'localhost:8080' if not in Docker

Grafana Environment (grafana.env)

Set default admin credentials (change these in production):

GF_SECURITY_ADMIN_USER=admin
GF_SECURITY_ADMIN_PASSWORD=admin

Running with Docker Compose

The repository includes a docker-compose.yml to spin up Prometheus and Grafana.

version: '3.9'
services:
  prometheus:
    image: prom/prometheus:latest
    container_name: prometheus
    volumes:
      - ./prometheus.yml:/etc/prometheus/prometheus.yml
    ports:
      - "9090:9090"

  grafana:
    image: grafana/grafana:latest
    container_name: grafana
    ports:
      - "3000:3000"
    env_file:
      - ./grafana.env
    depends_on:
      - prometheus

Start the services:

docker-compose up -d

• Access Prometheus at http://localhost:9090.
• Access Grafana at http://localhost:3000 (login with admin/admin).

Setting Up Grafana

1. Log in to Grafana.
2. Add Prometheus as a data source:
   • URL: http://prometheus:9090 (or http://localhost:9090 if accessing externally).
3. Import a dashboard:
   • Use the provided dashboard.json in the repository (if available), or search for "JVM Micrometer" on Grafana.com (Dashboard ID: 4701 or similar).
   • Example dashboard includes panels for JVM memory, CPU usage, HTTP requests, and more.

Usage

1. Test the Spring Boot API

   • Hit the example endpoint: curl http://localhost:8080/hello
   • This will generate metrics like http_server_requests_seconds_count.

2. View Metrics in Prometheus

   • Go to http://localhost:9090/targets to verify the scrape target.
   • Query metrics, e.g., jvm_memory_used_bytes.

3. Visualize in Grafana

   • Create or import dashboards to monitor metrics in real-time.

Troubleshooting

• Metrics not appearing? Ensure the /actuator/prometheus endpoint is accessible and Prometheus is configured to scrape it.
• Docker host issues: Replace host.docker.internal with your machine's IP if needed.
• Grafana login issues: Check the grafana.env file and restart the container.
• For more logs, run Docker Compose without -d.

Contributing

Feel free to fork the repository and submit pull requests. Issues and suggestions are welcome!

License

This project is licensed under the MIT License - see the LICENSE file for details.

References

• Spring Boot Actuator Documentation
• Micrometer Prometheus Registry
• Prometheus Documentation
• Grafana Documentation