torrefy

This package is still under heavy development. APIs are prone to change. Use with caution!!

torrefy

An ESM package that uses Web Streams API to create v1, v2 or hybrid torrents in your web browser

Install

npm i torrefy # or yarn add torrefy

Usage

Basic usage

import { create, encode, decode } from "torrefy";

// create a test file
const testFile = new File(
  ["Hello world. This is the test file content."],
  "testfile.txt"
);

// calculate (hash) the meta info of the test file
const metaInfo = await create([testFile]);

// bencode meta info into a readable stream
const torrentStream = encode(metaInfo);

// tee the readable stream into two readable streams
const [torrentStream1, torrentStream2] = torrentStream.tee();

// consume the first readable stream as an array buffer
const torrentBinary = await new Response(torrentStream).arrayBuffer();

// decode the second readable stream into meta info
const decodedMetaInfo = await decode(torrentStream2);

Advance usage

import {
  create,
  encode,
  decode,
  CommonPieceLength,
  TorrentType,
  TorrentOptions,
  OnProgress,
  ArrayKeyedMap,
  useArrayBufferPromiseHook,
  useTextPromiseHook,
} from "torrefy";

// create a test file
const testFile = new File(
  ["Hello world. This is the test file content."],
  "testfile.txt"
);

// v1 torrent options
const options: TorrentOptions<TorrentType.V1> = {
  type: TorrentType.V1,
  announceList: [
    ["udp://tracker.opentrackr.org:1337/announce"],
    ["udp://9.rarbg.com:2810/announce"],
  ],
  pieceLength: CommonPieceLength["16KB"],
};

// handle progress
const handleProgress: OnProgress = (current, total) => {
  console.log(((current / total) * 100).toFixed(2) + "%");
};

// calculate (hash) the meta info of the test file
const metaInfo = await create([testFile], options, handleProgress);

// use hooks when bencoding
const hooks = new ArrayKeyedMap();

// declare hook result as an array buffer promise
const [infoPromise, updateInfo] = useArrayBufferPromiseHook();
// register the above hook under "info" path
hooks.set(["info"], updateInfo);

// declare hook result as a text promise
const [piecesPromise, updatePieces] = useTextPromiseHook();
// register the above hook under "info.pieces" path
hooks.set(["info", "pieces"], updatePieces);

// bencode meta info into a readable stream with registered hooks
const torrentStream = encode(metaInfo, hooks);

// tee the readable stream into two readable streams
const [torrentStream1, torrentStream2] = torrentStream.tee();

// consume the first readable stream as an array buffer
const torrentBinary = await new Response(torrentStream1).arrayBuffer();

// get bencoded "info" as an array buffer
const info = await infoPromise;

// get bencoded "info.pieces" as a piece of text
const pieces = await piecesPromise;

// decode the second readable stream into meta info
const decodedMetaInfo = await decode(torrentStream2);

Todos

• BDecode implementation
• Magnet URI scheme (should be trivial)
• Convert all makeXXXTransformStream functional closure states to transformer class states (should be trivial)
• ArrayKeyedMap with ArrayBuffer keys (use proxy or drop suppport?)
• Convert typescript Enums to Unions (need investigation)
• Other type related issues (need investigation)
• Bundleless entry (need investigation)
• Support other common BEPs (need investigation)
• Add tests
• Add demo page