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Learn Blockchain Programming with JavaScript

You're reading from  Learn Blockchain Programming with JavaScript

Product type Book
Published in Nov 2018
Publisher Packt
ISBN-13 9781789618822
Pages 252 pages
Edition 1st Edition
Languages
Concepts
Author (1):
Eric Traub Eric Traub
Profile icon Eric Traub

Table of Contents (10) Chapters

Preface 1. Setting up the Project 2. Building a Blockchain 3. Accessing the Blockchain through an API 4. Creating a Decentralized Blockchain Network 5. Synchronizing the Network 6. Consensus Algorithms 7. Block Explorer 8. In conclusion... 9. Other Books You May Enjoy

Building the chainIsValid method

Let's start building the consensus algorithm by creating a new method called chainIsValid. This method will validate whether or not a chain is legitimate. Let's get started with building this method:

  1. In the blockchain.js file, after the proofOfWork method, let's define the method as follows:
Blockchain.prototype.chainIsValid = function() {

}
  1. Now, this method will take in a blockchain as an argument, and will return to us whether the blockchain is valid or not:
Blockchain.prototype.chainIsValid = function(blockchain) {

}

We're going to use this chainIsValid method to validate the other chains inside of the network when we are comparing them to the chain that is hosted on the current node. In order to validate that the blockchain is legitimate, we're simply going to iterate through every block inside of the blockchain...

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