README.md

Study about Spring Boot with Prometheus and Grafana

⤴️ Table of Contents

• ❓ About
  • 📊 System Diagrams
• 👩‍🏫 Learnings
• 🏃 How to Run
  • Run with Maven
  • Run with Docker
• 🚦 How to Test
  • Test with Maven, Test with Docker
• 📖 References

❓ About

Studies about Spring Boot with Prometheus and Grafana from the article Springboot App monitoring with Grafana & Prometheus by Vishnu M V.

Added some business metrics to Grafana and learned how to provision dashboards and datasources.

Back to Top

📊 System Diagrams

graph LR
    subgraph Linux
        A[Application]
    end

    subgraph Windows/MacOSX
        B[Application]
    end

    subgraph docker
        P[Prometheus] -- " study-springboot-grafana-prometheus-app-1:8080 " --> A
        P[Prometheus] -- " host.docker.internal:8080 " --> B
        G[Grafana] -- " prometheus:9090 " --> P
    end

Loading

Back to Top

👩‍🏫 Learnings

Very easy to enable it with spring boot actuator and there are dashboards ready for use.

Some difficulties getting it to work cross-platform. How docker networking works differently between Windows and Linux. There is no direct way to access the host IP address from within the container, making prometheus difficult to extract information from the application by Prometheus scraper.

More investigation would be needed to make the prometheus scraper work correctly on various OS platforms using only one target. For now, I have added both URLs to be discarded and accept that one of them will fail.

Back to Top

🏃 How to Run

Pre-requisites:

• Java 21
• Apache Maven
• Docker & Docker Compose

Initialize the Prometheus and Grafana with Docker Compose with the command:

docker compose up

Component	Url	User	Password
Prometheus	http://localhost:9090	-	-
Grafana	http://localhost:3000	admin	admin

Run with Maven

mvn spring-boot:run

Run with Docker

Linux/MacOSX:

docker run --rm \
  -p 8080:8080 \
  -w /app \
  -v ./src:/app/src \
  -v ./pom.xml:/app/pom.xml \
  -v data:/root/.m2 \
  --network=study-springboot-grafana-prometheus_monitoring \
  --name=/study-springboot-grafana-prometheus-app-1 \
  --label com.docker.compose.project=study-springboot-grafana-prometheus \
  maven:3.8.8-eclipse-temurin-21-alpine mvn spring-boot:run

Windows (PowerShell):

$srcPath = (Resolve-Path 'src').Path
$pomPath = (Resolve-Path 'pom.xml').Path

docker run --rm `
  -p 8080:8080 `
  -w /app `
  -v ${srcPath}:/app/src `
  -v ${pomPath}:/app/pom.xml `
  -v data:/root/.m2 `
  --network=study-springboot-grafana-prometheus_monitoring `
  --name=/study-springboot-grafana-prometheus-app-1 `
  --label com.docker.compose.project=study-springboot-grafana-prometheus `
  maven:3.8.8-eclipse-temurin-21-alpine mvn spring-boot:run

Back to Top

How to Test

Some endpoints to test the business metrics in Grafana.

Action	URI	Description
Flip a Coin	GET http://localhost:8080/api/flipCoin	Returns head or tail value and register a total count metric and another metric telling how many tails or heads

And below the Grafana Dashboards

Dashboard	URL	Description
Business Metrics	http://localhost:3000/d/d5ae9a0e-e1b5-4e87-8a0a-d0720cc17a88/business-metrics	Metrics added inside the application
JVM (Micrometer)	http://localhost:3000/d/d815b226-48af-4ecd-89de-50782a2d0ada/jvm-micrometer	Metrics related to the JVM
Spring Boot 3.x Statistics	http://localhost:3000/d/spring_boot_21_2/spring-boot-3-x-statistics	Metrics related to Spring Boot

Back to Top

📖 References

• Fonts icon used in this documentation.

Back to Top