Book Image

Blockchain Quick Start Guide

By : Xun (Brian) Wu, Weimin Sun
Book Image

Blockchain Quick Start Guide

By: Xun (Brian) Wu, Weimin Sun

Overview of this book

Blockchain is a technology that powers the development of decentralized applications.This technology allows the construction of a network with no single control that enables participants to make contributions to and receive benefits from the network directly. This book will give you a thorough overview of blockchain and explain how a blockchain works.You will begin by going through various blockchain consensus mechanisms and cryptographic hash functions. You will then learn the fundamentals of programming in Solidity – the defacto language for developing decentralize, applications in Ethereum. After that, you will set up an Ethereum development environment and develop, package, build, and test campaign-decentralized applications.The book also shows you how to set up Hyperledger composer tools, analyze business scenarios, design business models, and write a chain code. Finally, you will get a glimpse of how blockchain is actually used in different real-world domains. By the end of this guide, you will be comfortable working with basic blockchain frameworks, and develop secure, decentralized applications in a hassle-free manner.
Table of Contents (14 chapters)
Title Page
Copyright and Credits
About Packt

Writing a campaign decentralized application

We just deployed our smart contract on our local Ganache blockchain environment. Now, we will start to write UI code to trigger smart contract functions through an RPC call. The source code for this chapter is available here:

Selecting a web3 provider

When we load a web page, we need to connect to a web3 provider. If you have already installed a provider such as MetaMask, you can use your correct provider option, as follows:

App.web3Provider = web3.currentProvider;

In our crowdfunding example, for the sake of simplicity, we will directly connect to our local Ganache server, as follows:

App.web3Provider = new Web3.providers.HttpProvider('http://localhost:8545');

Loading account information

To load accounts, we define a drop-down menu with empty content, as follows:

<div class="form-group">
                <label for="exampleFormControlSelect1"&gt...