Calculator

A simple calculator app that performs basic arithmetic operations like addition, subtraction, multiplication, and division. The project is a monorepo managed by Turborepo. There are two apps - backend and frontend. Backend is just a very simple Express.js server exposing API endpoint that handles the logic of calculations. Frontend is a UI layer that renders calculator component and calls backend to get the result of the operation.

Tech stack

• Next.js, React (frontend)
• Node.js, Express.js (backend)
• Turborepo
• TypeScript
• Docker
• Jest, React Testing Library, MSW, Supertest

Source

• apps/backend - Express.js API
• apps/frontend - Next.js app
• packages/core - code to share between frontend and backend

Running locally

You need Node in version 18 (or higher) installed beforehand.

Install npm dependencies:

npm install

Run apps in dev mode:

npm run dev

You can now access services:

frontend http://localhost:3000
backend  http://localhost:3001

Running via Docker

Firstly create a network, which allows containers to communicate:

docker network calculator-network

Then, build docker images for backend and frontend:

npm run docker:build

Finally, run docker containers:

npm run docker:start

Ports used by dockerized services are the same as in "Running locally" section.

Tests

All packages and apps have tests using Jest as a test runner.
To run tests for all workspaces:

npm run test

To run tests for specific app/package (in this example: frontend):

npm run test -- --filter=@workspace/frontend

The value of the --filter argument comes from the package.json of targeted workspace.