Answers

I've added volta in order to have my node version automatically set.

Tests

You have all kind of tests implemented you can run them by:

yarn test:unit
yarn test:acceptance
yarn test:integration
yarn test:e2e

Or all of them by doing yarn test

For the inMemory implemenation even if we are depending on randomness, I've kept them for acceptance testing. As it is for the sake of the exercice, I've prefered to keep them and set the randomness to null, you'll see ;)

Wanna do more ?

Opaque types and Branded types could have been leverage but that's not the goal of the exercice I've decided to keep simple types

Introduction

This technical test has been designed to evaluate your ability to build decoupled, robust and well tested software. We don't intend to evaluate your algorithm, syntax or language proficiency here.

Goal

The idea of this technical test is to refactor the provided code to make it more testable and more decoupled. You can both change the code itself and add as many tests as you find necessary.

Rules

You can change the code implementation as much as you want as long as the behavior stays the same (end result and side effects).
You can add as many test types as you want (unit, acceptance, end to end, integration...).
The ./src/dependencies folder is read only and cannot be modified (consider it as your node_modules) but you are free to encapsulate those dependencies in dedicated modules to abstract them.
You can (and are encouraged) to split the src/index.ts file into as many files as you want and create a folder structure arround it.
You can add dependencies to the package.json file, although it should not be necessary. Don't hesitate to explain why if you do.

Advices

Following a hexagonal architecture might help you to acheive the goal of this test.
As you can see there is no real "finish line", you can stop this exercice whenever you think it's complete. That being said, as the code is pretty simple, you should not spend more than an hour to complete this task.
Even if this test's goal is to improve the testability of this code, the real end goal is to improve the overall quality of the app's architecture.
Don't forget to document how to launch your new test suites.
The ./src/test.unit.ts is only here as a (bad) example and should be deleted.

Instructions

Start by cloning this repository

git clone git@github.com:juliensnz/technical-test.git

Install dependencies

yarn install

Transpile TypeScript code to JavaScript

yarn build

Run command:

yarn newsletter:send

You should see a log in your console saying that a newsletter has been send

Launch the existing test suite:

yarn test

anaelChardan/kata-snz