MathApp

Application helps :

• Find sum of divisor of a number.

  http://localhost:8080/sumofdivisors/123
  

• Sort a csv string.

  curl -X POST http://localhost:8080/sortnumbers/1,2,4,3
  

Building Application

• Maven

  mvn clean package
  

• Creating Docker container image

  • Using 'dockerd'. Execute command project root.

    sudo docker build -t mathapp .
    

Starting Application

Spring Boot

• Open terminal at project root folder.

  java -Djava.security.egd=file:/dev/./urandom -jar MathApp-0.0.1-SNAPSHOT.jar
  

Docker

• Open terminal at project root folder.

  sudo docker run -p 8080:8080 -d mathapp
  

Kubernetes with Minikube

• Install instructions for K8s on linux machine.

  • Installing kubectl

    • Download version v1.19.0 on Linux, type:

      curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.19.0/bin/linux/amd64/kubectl
      

    • Make the kubectl binary executable.

      chmod +x ./kubectl
      

    • Move the binary in to your PATH.

      sudo mv ./kubectl /usr/local/bin/kubectl
      

    • Test to ensure the version you installed is up-to-date:

      kubectl version --client
      

  • Installing Minikube

    • Refer important instructions on installing correct hypervisor for your machine. VirtualBox is used here.

      • https://kubernetes.io/docs/tasks/tools/install-minikube/

    • Download Minikube with below instruction :

      curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 \
        && chmod +x minikube
      

    • Add executable to your path

      sudo mkdir -p /usr/local/bin/
      sudo install minikube /usr/local/bin/  
      

• Starting Application with Minikube

  • Start Minikube

    • To start Minikube for first time with VirtualBox

      minikube start --driver=virtualbox
      

    • To start if you have already built the image on VirtualBox once.

      minikube start
      

  • To ensure we use K8s (Minikube's) docker environment to upload docker image, execute the below commands.

    • To enable :

      eval $(minikube docker-env) 
      

    • To disable :

      eval $(minikube docker-env -u). 
      

  • Build the docker image using below command it will be published inside minikube’s environment

    docker build -t mathapp:mathapp .
    

  • Check if the image is present.

    docker images
    

  • The definition of K8s cluster can be defined in a file. Refer deployment.yaml.

  • Apply the definition to Minikube

    kubectl apply -f deployment.yaml
    

    Success output logs indicating the cluster is up.

    deployment.apps/mathapp created
    service/mathapp created
    

  • Get the url for the service to access the pods where application is running

    minikube service mathapp   
    

  • Append the REST endpoints to access the application service.

  • To delete the deployment

    kubectl delete deployment mathapp   
    

    ...and service

    kubectl delete -n default service mathapp
    

AWS

Deploy Strategy

• AWS CodePipeline
  • A push to code repository would auto trigger build for the project.
  • Unit tests are run in CodeBuild.
  • Docker image is created and published to ECR.
• ECS with Fargate
  • Deploy phase of the pipeline would deploy the newly generated container published in ECR to the already Fargate service.