OrangeTux / servus

Tooling for lz4 (de)compression using Wasm.

Servus

Using this project I'm exploring WebAssembly and it's ecosystem. This projects make a Rust implementation of the lz4 compression algorithm available in WebAssembly. A Python and Javascript implementation are provided that allow users to (de)compress files. Both implementation use Wasm.

Quickstart

First you need compile the Rust code in src/ to WebAssembly. wasm-pack is needed for that.

$ cargo install wasm-pack

$ make build

This command produces several files. Among them:

• pkg/servus_bg.wasm - the Rust library compiled to WebAssembly
• pkg/servus.js - glue code between Javascript and WebAssembly

Python

The python/ folder contains a script that uses a Wasm file to (de)compress files using lz4.

$ cd python
$ poetry install 
$ poetry shell
$ ./lz4.py --help
lz4 archive utility using Wasm.

USAGE:
    lz4 compress <file>
    lz4 decompress <file>

FLAGS:
        --help  Prints help information

ARGS:
    <file> Path to file that needs to be (de)compressed.

To compress a file:

venv> ./lz4.py compress pyproject.toml
Compressed pyproject.toml (436 bytes) to pyproject.toml.lz4 (333 bytes), reduction of 24%.

To decompress a file:

venv> ./lz4.py decompress pyproject.toml.lz4
Decompressed pyproject.toml.lz4 to pyproject.toml.

JavaScript

The www/ directory contains a file index.js which calls into the WASM files. The result of those calls is written the the browser's console.

Build the WASM file for the browser environment:

Start the webserver:

$ cd wwww/
$ npm install
$ npm start

Open http://localhost:8080 in your browser. The page shows two form fields to upload files. One to compress files, another to decompress files.