Practical WebAssembly: Explore the fundamentals of WebAssembly programming using Rust

232 Pages·2022·2.738 MB·English

by  Sendil Kumar Nellaiyapen

Practical
WebAssembly
Explore the fundamentals of WebAssembly
programming using Rust
Sendil Kumar Nellaiyapen
BIRMINGHAM—MUMBAI
Practical WebAssembly
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To all the amazing developers out there.
Contributors
About the author
Sendil Kumar Nellaiyapen is an engineering manager building web payments at Uber.
He is passionate about the web and cloud technologies. He has over 12 years of experience
in building distributed, cloud-native, and enterprise systems. He occasionally rambles on
his website and speaks at various conferences. He is an active open source contributor and
enjoys building communities. He loves to learn and explore new programming languages.
I want to thank the amazing Rust and web community.
About the reviewer
Sufyan bin Uzayr is a writer, teacher, and developer with 10+ years of experience in the
industry. He is an open source enthusiast and specializes in a wide variety of technologies.
He holds four master's degrees and has authored multiple books. Sufyan is an avid writer.
He regularly writes about topics related to coding, tech, politics, and sports. He is a regular
columnist for various publications and magazines. Sufyan is the CEO of Parakozm,
a software development company catering to a global clientele. He is also the CTO at
Samurai Servers, a web server management company focusing mainly on enterprise-scale
audiences. In his spare time, Sufyan teaches coding and English to young students. Learn
more about his works at https://sufyanism.com/.

Table of Contents
Preface
Section 1: Introduction to WebAssembly
1
Understanding LLVM
Technical requirements 4 Exploring LLVM 7
Understanding compilers 4 LLVM in action 8
Compiled languages 5 Summary 10
Compiler efficiency 6
2
Understanding Emscripten
Technical requirements 13 Listing the tools and SDK 24
Installing Emscripten using Managing the tools and SDK 25
emsdk 13
Understanding various levels
Generating asm.js of optimizations 28
using Emscripten 15
Optimizations 28
Running Hello World with
Closure Compiler 32
Emscripten in Node.js 17
Summary 34
Running Hello World with
Emscripten in the browser 20
Exploring other options
in emsdk 22
viii Table of Contents
3
Exploring WebAssembly Modules
Technical requirements 36 Exploring the WebAssembly
Understanding how text format 40
WebAssembly works 36 Building a function in WebAssembly
text format 45
Understanding JavaScript execution
inside the JavaScript engine 36
Summary 50
Understanding WebAssembly
execution inside the JavaScript engine 38
Section 2: WebAssembly Tools
4
Understanding WebAssembly Binary Toolkit
Technical requirements 54 Converting WAST into JSON 73
Getting started with WABT 54 Understanding a few other
tools provided by WABT 75
Installing WABT 54
wasm-objdump 75
Converting WAST into WASM 58
wasm-strip 78
Converting WASM into WAST 62
wasm-validate 79
-f or --fold-exprs 66 wasm-interp 81
Converting WASM into C 67 Summary 82
simple.h 68
simple.c 69
5
Understanding Sections in WebAssembly Modules
Technical requirements 84 Globals 89
Exports and imports 84 Start 95
Exports 84 Memory 96
Imports 87 Summary 100
Table of Contents ix
6
Installing and Using Binaryen
Technical requirements 102 wasm-dis 107
Installing and using Binaryen 102 wasm-opt 109
Linux/macOS 103 wasm2js 111
Windows 103 Summary 113
wasm-as 105
Section 3: Rust and WebAssembly
7
Integrating Rust with WebAssembly
Technical requirements 118 Installing wasm-bindgen 127
Installing Rust 118 Converting Rust into
Converting Rust into WebAssembly via
WebAssembly via rustc 120 wasm-bindgen 129
Converting Rust into Summary 135
WebAssembly via Cargo 123
8
Bundling WebAssembly Using wasm-pack
Technical requirements 138 How to use wasm-pack 150
Bundling WebAssembly
Packing and publishing using
modules with webpack 138
wasm-pack 153
Bundling WebAssembly
Summary 157
modules with Parcel 145
Introducing wasm-pack 150
Why do you need wasm-pack? 150