Modernise Healthcare Industry Operations with Springboot and Kubernetes

Containerization of Spring Boot Applications

To containerize Spring applications, I used Docker. Docker is an open platform for developing, shipping, and running applications. Docker enables you to separate your applications from your infrastructure so that you can deliver software quickly.To containerize the Springboot application, we must first create its Jar file. To create a jar file, we write a Docker file for it.
A sample DockerFile content looks like this

FROM openjdk:17-oracle
ARG JAR_FILE=target/*.jar
COPY ${JAR_FILE} app.jar
ENTRYPOINT [“java”,”-jar”,”/app.jar”]

Now to create jar, We will use maven.
Run Command:
mvn clean install -DskipTests.

This will generate a jar file of the spring app in the target folder.
Now to containerize this app we will write a docker compose file for it.

A sample docker compose file Configuration looks like this:
Docker-compose.yml
version: ‘3.8’
services:
userservice:
build: .
ports:
– “8081:8081”
depends_on:
– mysqldb
networks:
– backend
mysqldb:
image: mysql
restart: always
container_name: mysqldb
ports:
– 3306:3306
expose:
– 3306
volumes:
– mysql-vol:/var/lib/mysql
networks:
– backend
environment:
MYSQL_DATABASE: mydb
MYSQL_ROOT_PASSWORD: mypassword
MYSQL_USER: myuser
MYSQL_PASSWORD: mypassword
volumes:
mysql-vol:
networks:
backend:

Now to build docker image, we will go into directory of that file and
Run command: docker compose up -d
This will build a docker image of the application and also start a container of it.
To see images we can use the command:
Run command: docker images
Now add a tag to docker images.
Run the command: docker tag imageName:tagName
Now we have to push these images to docker hub.
To push these images to the docker hub.
First, we need to log into the docker hub account.
Run command:
docker login -u username
Enter password:
Now to push image to dockerhub:
Run command: docker push your-docker-username/your-image-name:your-tag

Deployment in Kubernetes:

For deployment, I used the inbuilt Kubernetes environment provided by docker desktop.To deploy these applications into Kubernetes We have to create a .yaml file.
A sample deployment file will look like this:
deployUserService.yaml
# Deployment configuration
apiVersion: apps/v1
kind: Deployment
metadata:
name: serviceregistry
spec:
replicas: 3
selector:
matchLabels:
app: serviceregistry
template:
metadata:
labels:
app: serviceregistry
spec:
containers:
– name: serviceregistry
image: rahulsharma1103/kubernetes_case_study:serviceregistry
ports:
– containerPort: 8761
‐‐‐
# Service configuration
apiVersion: v1
kind: Service
metadata:
name: serviceregistry-service
spec:
selector:
app: serviceregistry
ports:
– protocol: TCP
port: 80
targetPort: 8761
type: NodePort # Change this line to NodePort

To deploy this application run command got to directory of that file and
Run command:
kubectl apply -f your-deployment-file.yaml

Some other useful commands of kubernetes:
1. To see all deployments:
kubectl get deployments
2. To see details of a deployed application:
kubectl describes deployment sample-deployment
3. To see the status of pods:
kubectl get pods
4. To see the status of the particular pod:
kubectl describe pod <pod-name>
5. To delete a deployment:
kubectl delete deployment sample-deployment
6. If you want to delete all resources created by the deployment, including
pods, you can use the ‐‐all flag:
kubectl delete deployment sample-deployment ‐‐all