Spring Boot REST microservice

Java / Maven / Spring Boot microservice

Full integration with the latest Spring Framework 1.x: inversion of control, dependency injection, etc.
Packaging as a single jar with embedded container (tomcat 8)
Demonstrates how to set up healthcheck, metrics, info, environment, etc. endpoints automatically on a configured port. Inject your own health / metrics info with a few lines of code.
RESTful service using annotation: supports both XML and JSON request / response
Exception mapping from application exceptions to the right HTTP response with exception details in the body
Spring Data Integration with JPA/Hibernate
CRUD functionality with H2 in-memory data source using Spring Repository pattern
MockMVC test framework
Self-documented APIs: Swagger2 using annotations

Pre-requisites

TODO: for each app/tool add link to the installation page

macos x
sdkman
JDK
maven 3.x
curl
http
minikube
docker

Build and Run

This application is packaged as a jar which has Tomcat 8 embedded.

Clone this repository

git clone git@github.com:AndriyKalashnykov/spring-boot-rest-example.git
cd spring-boot-rest-example

Select JDK

sdk use java 8.0.232.hs-adpt

sdk use java 11.0.5.hs-adpt

Build the project and run the tests by running

mvn clean package

Run the service

  java -jar -Dspring.profiles.active=default target/spring-boot-rest-example-0.0.1.jar

  mvn spring-boot:run -Drun.arguments="spring.profiles.active=default"

Application health, configurations, documentation links

http://localhost:8081/env
http://localhost:8081/health
http://localhost:8081/info
http://localhost:8081/metrics
http://localhost:8081/configprops

http://localhost:8080/swagger-ui.html

Microservice API

curl -X POST 'http://localhost:8080/example/v1/hotels' --header 'Content-Type: application/json' --header 'Accept: application/json' --data @hotel.json --stderr -

http POST 'http://localhost:8080/example/v1/hotels' < hotel.json

curl -X POST 'http://localhost:8080/example/v1/hotels' --header 'Content-Type: application/json' --header 'Accept: application/json' -d '{"name":"Beds R Us","description":"Very basic, small rooms but clean","city":"Santa Ana","rating":2}' --stderr -

Retrieve a paginated list of hotels

curl -X GET --silent 'http://localhost:8080/example/v1/hotels?page=0&size=10' --stderr -  2>&1 | jq .

http  'http://localhost:8080/example/v1/hotels?page=0&size=10'

Swagger 2 API docs

open -a /Applications/Google\ Chrome.app http://localhost:8080/swagger-ui.html

Building docker image

Optional, local test only: Using local maven cache

In order to build image quickly by compiling maven project using host OS maven repo

Build project, artifact will be placed in $PWD/target

cd spring-boot-rest-example
docker run -v ~/.m2:/root/.m2 -v "$PWD":/usr/src -w /usr/src maven:3-jdk-8 mvn clean package

Build non multi-stage image using existing artifact in $PWD/target

cd spring-boot-rest-example
docker rm -f spring-boot-rest-example
docker build  -f Dockerfile.maven-host-cache -t spring-boot-rest-example .

Build multi-stage image

docker rm -f spring-boot-rest-example
docker build  -f Dockerfile.maven-multi-stage-layer-cached -t spring-boot-rest-example .

Test application

# adding 100 to port number to avoid local conflicts (McAfee runs on 8081)
docker run --name spring-boot-rest-example -p 8080:8080 -p 8181:8081 spring-boot-rest-example:latest

curl -X POST 'http://localhost:8080/example/v1/hotels' --header 'Content-Type: application/json' --header 'Accept: application/json' --data @hotel.json --stderr -

curl -X GET --silent 'http://localhost:8080/example/v1/hotels?page=0&size=10' --stderr -  2>&1 | jq .

Attaching to the application from IDE

Run the service with these command line options:

mvn spring-boot:run -Drun.jvmArguments="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005"

java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005 -Dspring.profiles.active=test -Ddebug -jar target/spring-boot-rest-example-0.0.1.jar

IntelliJ : Run -> Edit configuration -> Remote.

Deploy application to k8s

minikube delete --all
minikube start -p minikube --memory=16384 --cpus=6 --disk-size=30g --vm-driver=virtualbox
eval $(minikube docker-env)
eval "$(docker-machine env -u)"
# minikube start --vm-driver=virtualbox --extra-config=apiserver.anonymous-auth=false --insecure-registry=localhost:5000

mvn clean package -DskipTests -Pk8s fabric8:undeploy
mvn clean package -Pk8s fabric8:deploy

minikube ssh 'docker logs $(docker ps -a -f name=k8s_kube-api --format={{.ID}})'

Deploy application to k8s overriding runtime JDK/JRE

mvn clean package fabric8:deploy -Dfabric8.generator.from=fabric8/java-alpine-openjdk8-jdk

Test deployed application

curl -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' --data @hotel.json $(minikube service spring-boot-rest-example --url | sed -n 1p)/example/v1/hotels
http $(minikube service spring-boot-rest-example --url | sed -n 1p)/example/v1/hotels?page=0&size=10

http $(minikube service spring-boot-rest-example --url | sed -n 2p)/swagger-ui.html
http $(minikube service spring-boot-rest-example --url | sed -n 2p)/info
http $(minikube service spring-boot-rest-example --url | sed -n 2p)/health

Monitor k8s resources

kubectl get nodes --no-headers | awk '{print $1}' | xargs -I {} sh -c 'echo {}; kubectl describe node {} | grep Allocated -A 5 | grep -ve Event -ve Allocated -ve percent -ve -- ; echo'
kubectl top pod --all-namespaces

alexbrand / spring-boot-concourse-sample