Traub - Learn Blockchain programming with JavaScript: build your very own blockchain and decentralized network with JavaScript and Node.js

Copyright 2018 Packt Publishing

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Commissioning Editor: Kunal Chaudhari
Acquisition Editor: Devanshi Doshi
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First published: November 2018

Production reference: 1291118

Published by Packt Publishing Ltd.
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ISBN 978-1-78961-882-2

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Eric Traub currently works as a software engineer in New York City. He has extensive experience working as a teacher and instructing people in a variety of different subjects. He changed his career from teaching to software engineering because of the excitement it brings to him and the passion that he has for it. He is now lucky enough to have the opportunity to combine both of these passions software engineering and teaching!

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With the help of this book, you'll get to build your own blockchain prototype and a decentralized network by using the JavaScript programming language. Building your own blockchain will help you understand various concepts related to blockchains, such as how blockchain technology works under the hood, how decentralized blockchain networks function, and how to code the blockchain and decentralized network using JavaScript. Also, you will get to learn why blockchain is such a secure and valuable technology.

The blockchain that you'll build throughout this book will have functionalities that are similar to those you would find on a real-life blockchain, such as Bitcoin or Ethereum. Your blockchain will have functionalities such as the ability to mine new blocks, create new and immutable transactions, and perform a proof of work to secure the blockchain. In addition to these, your blockchain will consist of many other important features. You'll get to explore those as you read further through the chapters.

When you have completed this book, you will have a thorough understanding of how blockchain technology actually works and why this technology is so secure and valuable. You will also have a deep understanding of how decentralized blockchain networks function and why decentralization is such an important feature for securing the blockchain.

Learn Blockchain Programming with JavaScript is for JavaScript developers who wish to learn about blockchain programming or build their own blockchain using JavaScript frameworks.

, Setting Up the Project , covers what a blockchain actually is and enables readers to understand how it functions. Then, you'll get to learn how to set up a project in order to create your very own blockchain.

, Building a Blockchain , covers how to add various functionalities to your blockchain. You will implement the functionalities in the blockchain, creating some amazing methods such as createNewBlock, creatNewTransaction, and getLastBlock. Once these methods are added to the blockchain, you will test them to verify that they are working perfectly. Also, you'll get to learn about the hashing method, that is, SHA256 hashing, and then implement a method to generate a hash for your block data. Also, you'll get to explore what a proof of work is, how it benefits the blockchain, and how to implement it.

, Accessing the Blockchain through an API , explains how to set up Express.js in your project, as well as how to use it to build the API/server. Then, you will build various server endpoints for your blockchain and test these endpoints to verify whether or not they are working properly.