@icure/lzma-wasm

LZMA2 / XZ compression and decompression for browsers, web workers and Node.js, using liblzma (XZ Utils 5.6.4) compiled to WebAssembly with Emscripten.

Output is a standard .xz stream (LZMA2 filter, CRC64 check) that interoperates with the xz CLI.

Install

npm install @icure/lzma-wasm

Usage

import { lzmaWasmCompress, lzmaWasmDecompress } from '@icure/lzma-wasm'

const compressed: ArrayBuffer = await lzmaWasmCompress(new TextEncoder().encode('hello'), 6) // preset 0-9, default 6
const decompressed: ArrayBuffer = await lzmaWasmDecompress(compressed)

Both functions accept an ArrayBuffer or a Uint8Array and never modify their input. The WASM module is loaded lazily on first call. getLzmaModule() gives access to the raw Emscripten module.

Bundlers

dist/lzma.js locates lzma.wasm next to itself. When bundling for the browser, make sure lzma.wasm is emitted as an asset alongside the bundled glue code (e.g. webpack asset/resource, or copy it to your public directory).

Rebuilding the WASM module

The prebuilt src/lzma.js and src/lzma.wasm are committed. To rebuild them you need Emscripten (emcc) on your PATH:

npm run build:wasm   # downloads xz 5.6.4 into src/build, compiles src/lzma_wasm.c + liblzma
npm test

License

MIT for the code in this repository. liblzma is 0BSD (see LICENSE.liblzma).