webtorrentBencode
A node library for encoding and decoding bencoded data, according to the BitTorrent specification.
Index
About BEncoding
from Wikipedia:
Bencode (pronounced like B encode) is the encoding used by the peer-to-peer file sharing system BitTorrent for storing and transmitting loosely structured data.
It supports four different types of values:
- byte strings
- integers
- lists
- dictionaries
Bencoding is most commonly used in torrent files. These metadata files are simply bencoded dictionaries.
Install with npm
npm install bencodeUsage
import bencode from 'bencode'You can also use node-bencode with browserify to be able to use it in a lot of modern browsers.
Encoding
var data = {
string: 'Hello World',
integer: 12345,
dict: {
key: 'This is a string within a dictionary'
},
list: [ 1, 2, 3, 4, 'string', 5, {} ]
}
var result = bencode.encode( data )NOTE As of bencode@0.8.0, boolean values will be cast to integers (false -> 0, true -> 1).
Output
d4:dictd3:key36:This is a string within a dictionarye7:integeri12345e4:listli1ei2ei3ei4e6:stringi5edee6:string11:Hello WorldeDecoding
var data = Buffer.from('d6:string11:Hello World7:integeri12345e4:dictd3:key36:This is a string within a dictionarye4:listli1ei2ei3ei4e6:stringi5edeee')
var result = bencode.decode( data )Output
{
string: <Buffer 48 65 6c 6c 6f 20 57 6f 72 6c 64>,
integer: 12345,
dict: {
key: <Buffer 54 68 69 73 20 69 73 20 61 20 73 74 72 69 6e 67 20 77 69 74 68 69 6e 20 61 20 64 69 63 74 69 6f 6e 61 72 79>
},
list: [ 1, 2, 3, 4, <Buffer 73 74 72 69 6e 67>, 5, {} ]
}Automagically convert bytestrings to strings:
var result = bencode.decode( data, 'utf8' )Output
{
string: 'Hello World',
integer: 12345,
dict: {
key: 'This is a string within a dictionary'
},
list: [ 1, 2, 3, 4, 'string', 5, {} ]
}API
The API is compatible with the abstract-encoding specification.
bencode.encode( data, [buffer], [offset] )
Buffer|Array|String|Object|Number|BooleandataBufferbufferNumberoffset
Returns Buffer
bencode.decode( data, [start], [end], [encoding] )
BufferdataNumberstartNumberendStringencoding
If encoding is set, bytestrings are
automatically converted to strings.
Returns Object | Array | Buffer | String | Number
bencode.byteLength( value ) or bencode.encodingLength( value )
Buffer|Array|String|Object|Number|Booleanvalue