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)

Adding the currentNodeUrl

After testing our nodes, the next thing that we're going to do is alter the commands in our package.json slightly. The reason that we're going to do this is because we want each of our network nodes to be aware of what URL they are currently on. For example, they could be on http://localhost:3001, localhost:3002, localhost:3003, and so on. Therefore, we want each node to be aware of the URL that it is being hosted on.

In our package.json, as a third parameter to each of our commands, we are going to add the node's URL. Therefore, our first node's URL will simply be http://localhost:3001. It is likely that for our second node it will be http://localhost:3002. Similarly, you can add URLs for the remaining nodes, as shown in the following screenshot:

After adding the URLs, save the file. Now we have the URL of each node being passed...