MicroCalc: A dead-simple, polyglot, microservice-oriented calculator

Built with Istio and ❤️

Local run

Requirements: docker, docker-compose

Commands: $ docker-compose up

The application will be accessible at:

• Parser service: http://localhost:8080

Deploy to Kubernetes (Istio required)

Requirements: docker, nodejs, kubectl

Commands:

• Modify build-images.sh and replace the PROJECT_ID and IMAGE_PREFIX variables with proper values
• Modify gen-k8s.js and replace the IMG_PREFIX and APP_HOSTNAME with proper values
• Execute the following commands to build application images, push it to the private docker registry and generate the deployment template for Kubernetes:

$ ./build-images
$ node gen-k8s.js > deploy.yaml
$ kubectl create namespace microcalc
$ kubectl label namespace microcalc -l istio-injection=enabled
$ kubectl apply -f deploy.yaml -n microcalc

The application will be accessible at:

• Parser service: http://APP_HOSTNAME

Usage guide

• Parser service

POST /api/v1/calculate HTTP/1.1
Content-Type: application/json
[...]

{
    "input": "1+1"
}

HTTP/1.1 200 OK
content-type: application/json
[...]

{
    "operands": [
        1,
        1
    ],
    "origins": [
        {
            "result": 1,
            "service": "name: parser, version: v1"
        },
        {
            "result": 1,
            "service": "name: parser, version: v1"
        }
    ],
    "result": 2,
    "service": "name: add, version: v1"
}