Bunk Dev Test - Holiday Expenses Calculator

A code challenge for new developers applying to work at Bunk.

Challenge

The Bunk team are all going on a work holiday but they need an app to keep a track of expenses and who owes money to who at the end of the trip.

Technologies To Use

• TypeScript preferably, (JavaScript if not familiar with TypeScript)
• Angular 14+
• Node 14+ + Web Framework, i.e. Express
• Backend tests (ideally with Jest)
• E2E tests (ideally with Cypress)
• Git + Github for version control

Challenge Requirements

• The client-side should be built using Angular
• The client-side should contain a table showing a expenses with the following fields (per traveller):
  • Name
  • Expense
• You should be able to add an expense to the table (not persisted).
• The page should then have a "Settle Up" button.
• When the "Settle Up" button is clicked, it will make a request to the server to calculate how much each traveller needs to pay out to any other traveller
• The server-side should be a NodeJS Web API.
• The NodeJS server-side logic should be arranged into a service.
• There is no need for a database.

Bonus Requirements

• If you have time, you should write tests.
• Linting is appreciated, ideally with prettier.
• Tidy, well documented functions are great.

Installation

Run npm run install-all in the project root.

This script will kick off npm install in both the Express server (api) and the Angular application (web).

Quick Start

Run npm run start from the project root. This script will start both the Express server, and the Angular application.

Running Tests

Run server-side tests with npm test from the project root. Run E2E tests with the npm run e2e command from project root.

API Reference

Calculate Payouts (POST /payouts)

Endpoint URL http://localhost:3000/payouts

JSON Body Parameters

expenses - array : Specifies the expenses you want to calculate a payout on.

expenses.name - string : The name of the person who incurred the expense.

expenses.amount - number : The amount of the expense incurred.

Example Request

curl --location --request POST 'localhost:3000/payouts' \
--header 'Content-Type: application/json' \
--data-raw '{
	"expenses": [
		{ "name": "Adriana", "amount": 5.75 },
		{ "name": "Adriana", "amount": 5.75 },
		{ "name": "Bao", "amount": 12 }
	]
}'

Example Response

{
  "total": 23.5,
  "equalShare": 11.75,
  "payouts": [
    {
      "owes": "Adriana",
      "owed": "Bao",
      "amount": 0.25
    }
  ]
}

Submitting

When you have completed the test, please email a link to your public Github Repository to leta@gobunk.co.uk and alex@gobunk.co.uk.