parse-torrent/README.md

Parse a torrent and return an object of keys/values

# parse-torrent [![travis](https://img.shields.io/travis/feross/parse-torrent.svg)](https://travis-ci.org/feross/parse-torrent) [![npm](https://img.shields.io/npm/v/parse-torrent.svg)](https://npmjs.org/package/parse-torrent) [![downloads](https://img.shields.io/npm/dm/parse-torrent.svg)](https://npmjs.org/package/parse-torrent) [![gittip](https://img.shields.io/gittip/feross.svg)](https://www.gittip.com/feross/)

#### Parse a torrent file and return an object of keys/values.

[![browser support](https://ci.testling.com/feross/parse-torrent.png)](https://ci.testling.com/feross/parse-torrent)


Also works in the browser with [browserify](http://browserify.org/)! Works well with the buffers returned from [bencode](https://www.npmjs.org/package/bencode).

This module is used by [WebTorrent](http://webtorrent.io).

## install

```
npm install parse-torrent
```

## usage

```js
var parseTorrent = require('parse-torrent')

var torrent = fs.readFileSync(__dirname + '/torrents/leaves.torrent')
var parsed
try {
  parsed = parseTorrent(torrent)
} catch (e) {
  // the torrent file was corrupt
  console.error(e)
}

console.log(parsed.name) // Prints "Leaves of Grass by Walt Whitman.epub"
```

The `parsed` torrent object looks like this:

```js
{
  infoHash: 'd2474e86c95b19b8bcfdb92bc12c9d44667cfa36',
  name: 'Leaves of Grass by Walt Whitman.epub',
  private: false,
  created: new Date('Thu Aug 01 2013 06:27:46 GMT-0700 (PDT)'),
  announce: [
    'http://tracker.thepiratebay.org/announce',
    'udp://tracker.openbittorrent.com:80',
    'udp://tracker.ccc.de:80',
    'udp://tracker.publicbt.com:80',
    'udp://fr33domtracker.h33t.com:3310/announce'
  ],
  files: [
    {
      path: 'Leaves of Grass by Walt Whitman.epub',
      name: 'Leaves of Grass by Walt Whitman.epub',
      length: 362017,
      offset: 0
    }
  ],
  length: 362017,
  pieceLength: 16384,
  lastPieceLength: 1569,
  pieces: [
    '1f9c3f59beec079715ec53324bde8569e4a0b4eb',
    'ec42307d4ce5557b5d3964c5ef55d354cf4a6ecc',
    '7bf1bcaf79d11fa5e0be06593c8faafc0c2ba2cf',
    '76d71c5b01526b23007f9e9929beafc5151e6511',
    '0931a1b44c21bf1e68b9138f90495e690dbc55f5',
    '72e4c2944cbacf26e6b3ae8a7229d88aafa05f61',
    'eaae6abf3f07cb6db9677cc6aded4dd3985e4586',
    '27567fa7639f065f71b18954304aca6366729e0b',
    '4773d77ae80caa96a524804dfe4b9bd3deaef999',
    'c9dd51027467519d5eb2561ae2cc01467de5f643',
    '0a60bcba24797692efa8770d23df0a830d91cb35',
    'b3407a88baa0590dc8c9aa6a120f274367dcd867',
    'e88e8338c572a06e3c801b29f519df532b3e76f6',
    '70cf6aee53107f3d39378483f69cf80fa568b1ea',
    'c53b506159e988d8bc16922d125d77d803d652c3',
    'ca3070c16eed9172ab506d20e522ea3f1ab674b3',
    'f923d76fe8f44ff32e372c3b376564c6fb5f0dbe',
    '52164f03629fd1322636babb2c014b7dae582da4',
    '1363965261e6ce12b43701f0a8c9ed1520a70eba',
    '004400a267765f6d3dd5c7beb5bd3c75f3df2a54',
    '560a61801147fa4ec7cf568e703acb04e5610a4d',
    '56dcc242d03293e9446cf5e457d8eb3d9588fd90',
    'c698de9b0dad92980906c026d8c1408fa08fe4ec'
  ]
}
```

To convert a parsed torrent back into a .torrent file buffer, call `parseTorrent.toBuffer`.

```js
var parseTorrent = require('parse-torrent')

// parse a torrent
var parsed = parseTorrent(/* some buffer */)

// convert parsed torrent back to a buffer
var buf = parseTorrent.toBuffer(parsed)
```

## credit

This was originally based on [read-torrent](https://www.npmjs.org/package/read-torrent) by [mafintosh](https://twitter.com/mafintosh). It's basically a pared-down version of that, but it works in the browser (so [WebTorrent](http://webtorrent.io) can use it), doesn't have huge npm dependencies like `request` (saving on file size), and it has tests. Thanks for publishing good modules, mafintosh!

## license

MIT. Copyright (c) [Feross Aboukhadijeh](http://feross.org).