Node.js, JavaScript, API: Interview Questions and Answers

By John Edward Cooper Berg

Node.js is one of the most popular Javascript engine in IT. There is a growing demand for Node.js Software Engineers.

This book contains basic to expert level Node.js interview questions that an interviewer asks. Each question is accompanied with an answer.

Are you going to an interview?
You will be better prepared to interview. Interviewer won't surprise you.
In this book each question is followed by an answer so you can save time in interview preparation.
After going through this book 2-3 times, you will be very well prepared for an interview.

Are you a recruiter?
If you are a recruiter - you will know what questions you can ask. Feel free to copy some of my questions to your notebook.
The interviewee's answers should be similar to the answers I gave in the book.
You won't be able to ask all the questions from the book but try to ask a few questions from each chapter. You will then see what the candidate really knows.

This book contains the following chapters:
- Node.js - basics
- Npm
- JavaScript - basics
- Testing
- API
- Source code
- Patterns
- Miscellaneous

This book contains 129 questions and answers about Node.js, Npm, JavaScript, Testing and API.

This book has been released in 11.2019.

• Language: English
• Publisher: John Edward Cooper Berg
• Release date: Nov 20, 2019
• ISBN: 9780463906064

John Edward Cooper Berg

John is a software engineer, designer, architect, tech lead and technical recruiter with over 14 years of professional experience. Since 2012 he lives in Melbourne in Australia. He is passionate about software development and ways to make it better. When John is not on regular projects, he is spending time learning and investigating new technologies. John is a Udemy instructor.

Book preview

Node.js, JavaScript, API - Interview Questions and Answers

John Edward Cooper Berg

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Published by John Edward Cooper Berg

Copyright 2019-2020 John Edward Cooper Berg

Cover design and title page: John Edward Cooper Berg

Edit: John Edward Cooper Berg

Composition: John Edward Cooper Berg

Publisher: John Edward Cooper Berg

Contact to author: [e-mail]

License Notes

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the prior written permission of the publisher.

This book is licensed for your personal enjoyment only. This book may not be re-sold or given away to other people. If you would like to share this book with another person, please purchase an additional copy for each recipient. If you’re reading this book and did not purchase it, or it was not purchased for your use only, then please return to your favourite book retailer and purchase your own copy. Thank you for respecting the hard work of this author.

Contents

NODE.JS - BASICS

NPM

JAVASCRIPT - BASICS

TESTING

API

SOURCE CODE

PATTERNS

MISCELLANEOUS

Acknowledgement

My Udemy course

NODE.JS - BASICS

Q. What is Node.JS?

Node.js is an open-source, cross-platform, JavaScript run-time environment that executes JavaScript code outside of a browser. Node.js lets developers use JavaScript to write command line tools and for server-side scripting—running scripts server-side to produce dynamic web page content before the page is sent to the user's web browser. Consequently, Node.js represents a JavaScript everywhere paradigm, unifying web application development around a single programming language, rather than different languages for server- and client-side scripts.

Q. What are Node.JS advantages?

- is fast

- almost never blocks

- offers a unified programming language and data type

- everything is asynchronous

Q. What is Event Driven Programming followed in Node.js?

Event-Driven Programming makes use of the following concepts:

An Event Handler is a callback function that will be called when an event is triggered.

A Main Loop listens for event triggers and calls the associated event handler for that event.

Node.js natively provides a module called EventEmitter that allows us to get started incorporating Event-Driven Programming in our project.

Q. Describe please Node.js architecture

Node.js brings event-driven programming to web servers, enabling development of fast web servers in JavaScript. Developers can create scalable servers without using threading, by using a simplified model of event-driven programming that uses callbacks to signal the completion of a task. Node.js connects the ease of a scripting language (JavaScript) with the power of Unix network programming.

Node.js was built on the Google V8 JavaScript engine since it was