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

Implementing the business transaction function

We learned how to implement a transaction function in the previous section by reviewing SampleTransaction. Following a similar approach, we will implement an insurance claim transaction function. Rename sample.js to logic.js.

Implement the Init function, as follows:

Init() function is used to register insuree person information.
  * Create the insuree
  * @param {com.packt.quickstart.claim.Init} initalAppliation - the InitialApplication transaction
  * @transaction
 async function Init(application) { // eslint-disable-line no-unused-vars
     const factory = getFactory();
     const namespace = 'com.packt.quickstart.claim';
     const insuree = factory.newResource(namespace, 'Insuree', application.insureeId);
     insuree.firstName = application.firstName;;     insuree.lastName = application.lastName

     insuree.ssn = application.ssn;;
     insuree.policyNumber = application.policyNumber;;
     const participantRegistry = await