Bencode

A node library for encoding and decoding bencoded data, according to the BitTorrent specification.

bencode.js uses indutny/bn.js as Integer because JavaScript support only 53-bit precise integers :(

Install with npm

npm install bencode.js

Usage

var bencode = require('bencode.js')
var data = {
  string: new Buffer('Hey there!'),
  integer: new bencode.BN(42),
  dict: { key: new Buffer('dict-key-string') },
  list: [ new bencode.BN(1), new Buffer('str'), new bencode.BN(5), {}, [] ]
}

console.log(bencode.encodingLength(data))
// 90

var encoded = bencode.encode(data)
console.log(encoded.toString())
// d4:dictd3:key15:dict-key-stringe7:integeri42e4:listli1e3:stri5edelee6:string10:Hey there!e

console.log(bencode.decode(encoded))
// { dict: { key: <Buffer 64 69 63 74 2d 6b 65 79 2d 73 74 72 69 6e 67> },
//   integer: <BN: 2a>,
//   list: [ <BN: 1>, <Buffer 73 74 72>, <BN: 5>, {}, [] ],
//   string: <Buffer 48 65 79 20 74 68 65 72 65 21> }

Benchmark

Torrent file for benchmark: Fedora-Live-MATE_Compiz-x86_64-23.torrent

$ cd benchmark
$ npm i
...
$ npm start
                      decode
          33,311 op/s » bencode
          34,559 op/s » bencode.js
          23,026 op/s » bencoding
          33,448 op/s » dht_bencode
             546 op/s » bncode
          27,194 op/s » dht

                      encode
          11,413 op/s » bencode
          11,562 op/s » bencode.js
           6,444 op/s » bencoding
           8,108 op/s » dht_bencode
           5,586 op/s » bncode
          10,278 op/s » dht

License

MIT