Book Image

Learn Blockchain Programming with JavaScript

By : Eric Traub
Book Image

Learn Blockchain Programming with JavaScript

By: Eric Traub

Overview of this book

Learn Blockchain Programming with JavaScript begins by giving you a clear understanding of what blockchain technology is. You’ll then set up an environment to build your very own blockchain and you’ll add various functionalities to it. By adding functionalities to your blockchain such as the ability to mine new blocks, create transactions, and secure your blockchain through a proof-of-work you’ll gain an in-depth understanding of how blockchain technology functions. As you make your way through the chapters, you’ll learn how to build an API server to interact with your blockchain and how to host your blockchain on a decentralized network. You’ll also build a consensus algorithm and use it to verify data and keep the entire blockchain network synchronized. In the concluding chapters, you’ll finish building your blockchain prototype and gain a thorough understanding of why blockchain technology is so secure and valuable. By the end of this book, you'll understand how decentralized blockchain networks function and why decentralization is such an important feature for securing a blockchain.
Table of Contents (10 chapters)

Consensus Algorithms

In this chapter, we're going to build a consensus algorithm for the blockchain network. A consensus algorithm is a way for all of the nodes inside of the network to agree upon which data is correct and should be retained inside the blockchain. In order to build the consensus algorithm, we are first going to build a new method, called chainIsValid. This method will simply validate a blockchain by comparing all of the hashes of all of the blocks inside of the chain. After that, we are going to build a /consensus endpoint that we will hit whenever we want to use the consensus algorithm.

In this chapter, we're going to learn about the following:

  • What the consensus algorithm is
  • Building and testing the chainIsValid method
  • Building and testing the /consesnsus endpoint

So, let's get started with the consensus algorithm.