📦✨ wasm-pack

Your favorite rust -> wasm workflow tool!

This tool seeks to be a one-stop shop for building and working with rust- generated WebAssembly that you would like to interop with JavaScript, in the browser or with Node.js. wasm-pack helps you build and publish rust-generated WebAssembly to the npm registry to be used alongside any other javascript package in workflows that you already use, such as webpack or greenkeeper.

This project is a part of the rust-wasm group. You can find more info by visiting that repo!

🔮 Prerequisities

This project requires Rust 1.30.0 or later.

• Development Environment
• Installation
• Project Setup

🎙️ Commands

• init (⚠️ DEPRECATED): This command has been deprecated since release 0.5.0, in favor of build. 0.4.2 and previous use this command.
• build: Generate an npm wasm pkg from a rustwasm crate
• pack and publish: Create a tarball of your rustwasm pkg and/or publish to a registry

📝 Logging

wasm-pack uses env_logger to produces logs when wasm-pack runs.

To configure your log level, use the RUST_LOG environment variable. For example:

RUST_LOG=info wasm-pack build

👯 Contributing

Read our guide on getting up and running for developing wasm-pack, and check out our contribution policy.

⚡ Quickstart Guide

1. Write a crate in Rust.
2. Add wasm-bindgen to your Cargo.toml:

[lib]
crate-type = ["cdylib"]

[dependencies]
wasm-bindgen = "0.2"

3. Add this to the top of your src/lib.rs:

extern crate wasm_bindgen;

use wasm_bindgen::prelude::*;

4. Annotate your public functions with #[wasm_bindgen], for example:

#[wasm_bindgen]
extern {
    pub fn alert(s: &str);
}

#[wasm_bindgen]
pub fn greet(name: &str) {
    alert(&format!("Hello, {}!", name));
}

5. Install this tool: cargo install wasm-pack
6. Run wasm-pack build, optionally, pass a path to a dir or a scope (see above for details)
7. This tool generates files in a pkg dir
8. To publish to npm, run wasm-pack publish. You may need to login to the registry you want to publish to. You can login using wasm-pack login.