/json-test

Primary LanguageJava

Helidon Example: quickstart-se

This example implements a simple Hello World REST service.

Prerequisites

  1. Maven 3.5 or newer
  2. Java SE 8 or newer
  3. Docker 17 or newer to build and run docker images
  4. Kubernetes minikube v0.24 or newer to deploy to Kubernetes (or access to a K8s 1.7.4 or newer cluster)
  5. Kubectl 1.7.4 or newer to deploy to Kubernetes

Verify prerequisites

java -version
mvn --version
docker --version
minikube version
kubectl version --short

Build

mvn package

Start the application

java -jar target/quickstart-se.jar

Exercise the application

curl -X GET http://localhost:8080/greet
{"message":"Hello World!"}

curl -X GET http://localhost:8080/greet/Joe
{"message":"Hello Joe!"}

curl -X PUT -H "Content-Type: application/json" -d '{"greeting" : "Hola"}' http://localhost:8080/greet/greeting

curl -X GET http://localhost:8080/greet/Jose
{"message":"Hola Jose!"}

Try health and metrics

curl -s -X GET http://localhost:8080/health
{"outcome":"UP",...
. . .

# Prometheus Format
curl -s -X GET http://localhost:8080/metrics
# TYPE base:gc_g1_young_generation_count gauge
. . .

# JSON Format
curl -H 'Accept: application/json' -X GET http://localhost:8080/metrics
{"base":...
. . .

Build the Docker Image

docker build -t quickstart-se target

Start the application with Docker

docker run --rm -p 8080:8080 quickstart-se:latest

Exercise the application as described above

Deploy the application to Kubernetes

kubectl cluster-info                # Verify which cluster
kubectl get pods                    # Verify connectivity to cluster
kubectl create -f target/app.yaml   # Deply application
kubectl get service quickstart-se  # Get service info