Kube Spring Fibonacci

Containerized microservice that exposes an endpoint for calculating the n-th sequence of fibonacci.

This is a project for testing purposes.

Prerequisites

• Java 11
• Minikube
• Docker

Microservice

Features

• Microservice developed using Spring Boot
• Fibonacci sequence calculated using fast doubling method

Run

> ./gradlew bootRun

Test

> curl http://localhost:8000/fib?n=1
1

> curl http://localhost:8000/fib?n=10
55

> curl http://localhost:8000/fib?n=72
498454011879264

Containerization

Features

• Multi-stage Dockerfile
• Docker compose file included
• Kubernetes with Horizontal Pod Autoscaler

Docker image build

> docker build -t <docker-image-name> .

Docker container run

> docker compose up

Kubernetes deploy

Please enable metrics-server minikube addon in order to allow HPA to work properly.

> minikube addons enable metrics-server
> minikube start

> kubectl apply -f fib.yaml
> minikube tunnel

Kubernetes manual scale

> kubectl scale --replicas=<expected_replica_num> deployment kube-spring-fibonacci-deployment