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
Contributors
Preface
Index

Case study – crowdfunding campaign


In this section, we will implement and deploy the smart contract for the crowdfunding campaign use case.

The idea of crowd funding is a process of raising funds for a project or venture from the masses. Investors receive tokens that represent a share of the startup they invested. The project sets up a predefined goal and a deadline for reaching it. Once a project misses the goal, the investments are returned, which reduces the risk for investors. This decentralized fundraising model can supplant the fund need for startup, and there is no need for a centralized trusted platform. Investors will only pay the gas fees if the fund returns. Any project contributor gets a token, and they can trade, sell, or keep these tokens. In a certain stage, the token can be used in exchange for real products as the physical reward.

Define struct and events, shown as follows:

pragma solidity ^0.4.24;

contract CrowdFunding {

    Project public project;
    Contribution[] public...