Solution

Prerequisites

1. Install kubectl and minikube. Make minikube start to initialize your local kubernetes cluster. Check that cluster is configured correctly with kubectl get nodes or kubectl get all
2. Install helm and make helm init
3. You must have docker installed.
4. You must have an account on Docker Hub. PS. In my example I will use my own flomsk account.

Installation steps

• Now you have to build containers and upload them to Docker Hub.
  • docker login - enter your credentials to Docker Hub
  • start script which builds and uploads images to docker hub. /bin/bash upload-images.sh HUBUSERNAME HUBREPOSITORY. In my case it will be ./upload-images.sh flomsk join-apps. Repository name we will need in the next steps.
• Next step is to install nginx-ingress-controller. helm install --namespace ingress --name proxy stable/nginx-ingress
• Make a changes in join-apps/values.yaml. You must specify your image repository and prefered ingress hostname. Or you can leave as is and use my set.
• Start the main helm chart. helm install --name acceleration join-apps. Then you will see NOTES about how to verify your installation.

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Infrastructure Engineer (DevOps) Challenge

The context

This challenge addresses a web application with a microservice architecture to calculate the acceleration of an object.

The application

• The application contains 3 microservices
• Each microservice takes care of only one arithmetic operation
• The microservices take inputs from the URL query form and return the result in JSON format
• The microservices are not stable and can stop serving requests

Services:

• acceleration-dv calculates 𝚫v=vf-vi

curl http://127.0.0.1:3001/dv?vf=200&vi=5
{"dv":195}

• acceleration-a calculates a=𝚫v/t

curl http://127.0.0.1:3002/a?dv=200&t=5
{"a":40}

• acceleration-calc coordinates request to acceleration-dv and acceleration-a services

curl http://127.0.0.1:3000/calc?vf=200&vi=5&t=123
{"a":1.5853658536585367}

Task

• Using Helm, write the necessary Kubernetes deployment and service files that can be used to create the full application, running 2 instances of each microservice.
• Only /calc of acceleration-calc microservices can be available outside of the kubernetes cluster.
• Run the application on a kubernetes cluster like Minikube or Docker for Mac.
• Make sure the application is stable.

Environment Setup

• Microservices are written on Typescript and Node.js version 10.14.2
• You would need to setup yarn
• Run yarn install to setup all required components
• Run yarn build to build production ready code
• Run yarn dev to run a service in dev environment
• Run yarn start to run a service in production

Instructions

• Fork this repo
• The challenge is on!
• Create a pull request
• Please complete your working solution within 7 days of receiving this challenge, and be sure to notify us when it is ready for review.