Foras

WebAssembly port of Deflate, Gzip, and Zlib compression algorithms

npm i @hazae41/foras

Node Package 📦 • Deno Module 🦖 • Next.js CodeSandbox 🪣

Algorithms

• Deflate from flate2
• Gzip from flate2
• Zlib from flate2

Features

• Reproducible building
• Pre-bundled and streamed
• Zero-copy memory slices

Usage

Direct

import { Foras, deflate, inflate } from "@hazae41/foras";
// or { Foras, gzip, gunzip }
// or { Foras, zlib, unzlib }

// Wait for WASM to load
await Foras.initBundledOnce()

const bytes = new TextEncoder().encode("Hello world")

const compressed = deflate(bytes).copyAndDispose()
const decompressed = inflate(compressed).copyAndDispose()

Streaming

import { Foras, DeflateEncoder, DeflateDecoder } from "@hazae41/foras";
// or { Foras, GzEncoder, GzDecoder }
// or { Foras, ZlibEncoder, ZlibDecoder }

// Wait for WASM to load
await Foras.initBundledOnce()

const bytes = new TextEncoder().encode("Hello world")

const compresser = new DeflateEncoder()
compresser.write(bytes)
compresser.flush()

const compressed1 = compresser.read().copyAndDispose()
const compressed2 = compresser.finish().copyAndDispose()

compresser.free()

Building

Unreproducible building

You need to install Rust

Then, install wasm-pack

cargo install wasm-pack

Finally, do a clean install and build

npm ci && npm run build

Reproducible building

You can build the exact same bytecode using Docker, just be sure you’re on a linux/amd64 host

docker compose up --build

Then check that all the files are the same using git status

git status --porcelain

If the output is empty then the bytecode is the same as the one I commited

Automated checks

Each time I commit to the repository, the GitHub’s CI does the following:

• Clone the repository
• Reproduce the build using docker compose up --build
• Throw an error if the git status --porcelain output is not empty

Each time I release a new version tag on GitHub, the GitHub’s CI does the following:

• Clone the repository
• Do not reproduce the build, as it’s already checked by the task above
• Throw an error if there is a npm diff between the cloned repository and the same version tag on NPM

If a version is present on NPM but not on GitHub, do not use!