Book Image

Solidity Programming Essentials - Second Edition

By : Ritesh Modi
Book Image

Solidity Programming Essentials - Second Edition

By: Ritesh Modi

Overview of this book

Solidity is a high-level language for writing smart contracts, and the syntax has large similarities with JavaScript, thereby making it easier for developers to learn, design, compile, and deploy smart contracts on large blockchain ecosystems including Ethereum and Polygon among others. This book guides you in understanding Solidity programming from scratch. The book starts with step-by-step instructions for the installation of multiple tools and private blockchain, along with foundational concepts such as variables, data types, and programming constructs. You’ll then explore contracts based on an object-oriented paradigm, including the usage of constructors, interfaces, libraries, and abstract contracts. The following chapters help you get to grips with testing and debugging smart contracts. As you advance, you’ll learn about advanced concepts like assembly programming, advanced interfaces, usage of recovery, and error handling using try-catch blocks. You’ll also explore multiple design patterns for smart contracts alongside developing secure smart contracts, as well as gain a solid understanding of writing upgradable smart concepts and data modeling. Finally, you’ll discover how to create your own ERC20 and NFT tokens from scratch. By the end of this book, you will be able to write, deploy, and test smart contracts in Ethereum.
Table of Contents (21 chapters)
1
Part 1: The Fundamentals of Solidity and Ethereum
7
Part 2: Writing Robust Smart Contracts
13
Part 3: Advanced Smart Contracts

Implementing advanced solutions using proxy contracts

The word proxy means on behalf of. Proxy is one of the established patterns in the design pattern world. Generally, functions are directly invoked in a smart contract. This induces tight coupling between the caller and the contract called. To induce upgradability and manageability, this direct link between contracts should be removed and an additional abstraction called proxy contracts introduced instead. The proxy contract stays in between the caller and called contract and ensures that a two-way request-response operation can be handled between them.

In a proxy contract implementation, the caller does not invoke functions directly on the target contract. Instead, the caller knows about the proxy contract and invokes functions on the proxy contract. It is the job of the proxy contract to take the request from the caller contract, optionally modify the request, and invoke the actual function from the main contract implementing...