zbencode/index.js

Bencoding for bittorrent

module.exports = bencode

function bencode (input) {
  var encoder = get_encoder(input)
  return encoder(input)
}

var types = {
  '[object String]': bencode_string,
  '[object Object]': bencode_dict,
  '[object Array]': bencode_list,
  '[object Number]': bencode_integer
}

function get_encoder (input) {
  var type = Object.prototype.toString.call(input)
  return types[type]
}

function bencode_list (array) {
  var list = 'l'
  var parts = array.map(bencode)
  return list.concat(parts.join(''), 'e')
}

function bencode_dict (object) {
  var dict = 'd'
  var keys = Object.keys(object)
  keys.sort()
  keys.forEach(function (key) {
    dict += bencode(key)
    dict += bencode(object[key])
  })
  dict += 'e'
  return dict
}
function bencode_string (string) {
  return string.length + ':' + string
}

function bencode_integer (integer) {
  return 'i' + integer + 'e'
}