unbzip2-multistream

streaming bzip2 decompressor in pure TypeScript for Node.js and browsers.

Cross-platform compatibility

This package works identically across Node.js, browsers, Deno, and other JavaScript environments. It has zero runtime dependencies and uses standard Web APIs (ArrayBuffer, Uint8Array, async iteration) that are available everywhere.

Usage

import unbzip2Stream = require('@ckirby/unbzip2-multistream');

// For Node.js streams
const fs = require('fs');
const { Readable } = require('node:stream');

// Example usage
(async () => {
    const inputStream = Readable.from(fs.createReadStream('./test.bz2'));
    for await (const chunk of unbzip2Stream(inputStream)) {
        process.stdout.write(chunk);
    }
})();

Browser usage

// Simple helper to convert ReadableStream to async iterable
function readableStreamToAsyncIterable(stream) {
  return (async function* () {
    const reader = stream.getReader();
    try {
      while (true) {
        const { done, value } = await reader.read();
        if (done) return;
        yield value; // value is Uint8Array
      }
    } finally {
      reader.releaseLock();
    }
  })()
}

fetch('/file.bz2')
    .then(response => unbzip2Stream(readableStreamToAsyncIterable(response.body)))
    .then(async (stream) => {
        for await (const chunk of stream) {
            // process each decompressed chunk (Uint8Array)
        }
    });

Tests

To run tests:

npm test

To run long-running benchmarks:

npm run prepare-long-test
npm run long-test

Features

• Zero dependencies: Pure TypeScript implementation with no external runtime dependencies
• Cross-platform: Works in Node.js, browsers, Deno, and other JS environments
• Streaming: Processes data incrementally, suitable for large files
• Multi-stream support: Handles concatenated bzip2 streams
• TypeScript: Full type definitions included

API

The package exports a single async generator function that takes any object implementing Symbol.asyncIterator that yields Uint8Array chunks and returns an async iterable of decompressed Uint8Array chunks.