Programming WebAssembly with Rust: Unified Development for Web, Mobile, and Embedded Applications

231 Pages·2019·4.062 MB·English

by  Kevin Hoffman

Early praise for Programming WebAssembly with Rust
Concise and well-paced, this book quickly dives into the details of WebAssembly,
letting readers get their hands dirty building interesting Wasm applications. It’s
loaded with great examples and touches on many different aspects of programming
while paving the trail for WebAssembly development.
➤ Sean Boyle
Senior Software Engineer, Cerner
Programming WebAssembly with Rust is a great resource for learning a low-level
language (WebAssembly) and showing how its power can be harnessed with Rust.
It is perfect for people who like to understand how things work.
➤ Jason Pike
Software Development Coach, Sigao Studios
Starting with a detailed look at WebAssembly internals and the WAST language
before moving on to solving fun gaming problems with Rust and Wasm, Program-
ming WebAssembly with Rust ensures readers gain a foundational knowledge of
WebAssembly and have fun doing so.
➤ Balaji Sivaraman
Senior Technology Consultant, ThoughtWorks
I read Programming WebAssembly with Rust hardly knowing anything about either.
I came away planning to make some time to build a WebAssembly module and
publish to an npm registry—and with a clear idea of how to do so. An enjoyable
read which suggests some mind-bending possibilities for the future of the web.
➤ Stephen Wolff
Director, Max Gate Digital Ltd.
Programming WebAssembly with Rust
Unified Development for Web, Mobile, and Embedded Applications
Kevin Hoffman
The Pragmatic Bookshelf
Raleigh, North Carolina
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ISBN-13: 978-1-68050-636-5
Book version: P1.0—March 2019
For my grandfather—Walter K. MacAdam—
inventor, tinkerer, and IEEE president. He
quietly supported my exposure to computers
and programming throughout my childhood,
often in ways I didn’t know until after his death.
I always wanted to grow up to be like him, and
I only wish he could’ve seen this book.

Contents
Acknowledgments . . . . . . . . . . . xi
Introduction . . . . . . . . . . . . xiii
Part I — Building a Foundation
1. WebAssembly Fundamentals . . . . . . . . . 3
Introducing WebAssembly 3
Understanding WebAssembly Architecture 8
Building a WebAssembly Application 12
Wrapping Up 17
2. Building WebAssembly Checkers . . . . . . . 19
Playing Checkers, the Board Game 19
Coping with Data Structure Constraints 20
Implementing Game Rules 34
Moving Players 35
Testing Wasm Checkers 38
Wrapping Up 41
Part II — Interacting with JavaScript
3. Wading into WebAssembly with Rust . . . . . . . 45
Introducing Rust 45
Installing Rust 47
Building Hello WebAssembly in Rust 47
Creating Rusty Checkers 50
Coding the Rusty Checkers WebAssembly Interface 60
Playing Rusty Checkers in JavaScript 64
Wrapping Up 65
Contents • viii
4. Integrating WebAssembly with JavaScript . . . . . 67
Creating a Better “Hello, World” 67
Building the Rogue WebAssembly Game 73
Experimenting Further 87
Wrapping Up 88
5. Advanced JavaScript Integration with Yew . . . . . 89
Getting Started with Yew 89
Building a Live Chat Application 99
Wrapping Up 112
Part III — Working with Non-Web Hosts
6. Hosting Modules Outside the Browser . . . . . . 115
How to Be a Good Host 115
Interpreting WebAssembly Modules with Rust 117
Building a Console Host Checkers Player 120
Wrapping Up 129
7. Exploring the Internet of WebAssembly Things . . . . 131
Overview of the Generic Indicator Module 132
Creating Indicator Modules 135
Building Rust Applications for ARM Devices 140
Hosting Indicator Modules on a Raspberry Pi 141
Hardware Shopping List 150
Endless Possibilities 152
Wrapping Up 154
8. Building WARoS—The WebAssembly Robot System . . . 155
An Homage to Crobots 156
Designing the WARoS API 157
Building the WARoS Match Engine 162
Creating WebAssembly Robots 186
Robots in the Cloud 191
Wrapping Up 191
Conclusion 192
A1. WebAssembly and Serverless . . . . . . . . 193
Serverless 101 193
Intersection of WebAssembly and Serverless 194
WebAssembly in the Cloud 194