torrent-discovery

Discover BitTorrent and WebTorrent peers

This module bundles bittorrent-dht, bittorrent-tracker, and bittorrent-lsd clients and exposes a single API for discovering BitTorrent peers via both discovery methods.

features

• simple API
• find peers from trackers, DHT, and LSD
• automatically announces, so other peers can discover us
• can start finding peers with just an info hash, before full metadata is available

This module also works in the browser with browserify. In that context, it discovers WebTorrent (WebRTC) peers.

install

npm install torrent-discovery

api

discovery = new Discovery(opts)

Create a new peer discovery instance. Required options are:

{
  infoHash: '', // as hex string or Buffer
  peerId: '',   // as hex string or Buffer
  port: 0       // torrent client port (only required in node)
}

Optional options are:

{
  announce: [],  // force list of announce urls to use (from magnet uri)
  dht: true,     // use dht? optionally, this can be an `opts` object, or a DHT instance to use (can be reused for multiple torrents)
  dhtPort: 0,    // custom listen port for the DHT instance (not used if DHT instance is given via `opts.dht`)
  userAgent: '', // User-Agent header for http requests
  tracker: true, // use trackers? optionally, this can be an `opts` object
  lsd: true      // use lsd?
}

See the documentation for bittorrent-dht, bittorrent-tracker and bittorrant-lsd for information on what options are available via the opts object.

This module automatically handles announcing on intervals, for maximum peer discovery.

discovery.updatePort(port)

When the port that the torrent client is listening on changes, call this method to reannounce to the tracker and DHT with the new port.

discovery.complete([opts])

Announce that download has completed (and the client is now a seeder). This is only used by trackers, for statistical purposes. If trackers are not in use, then this method is a no-op.

Optional opts object with the following options:

{number=} opts.uploaded
{number=} opts.downloaded
{number=} opts.numwant
{number=} opts.left (if not set, calculated automatically)

discovery.destroy()

Destroy and cleanup the DHT, tracker, and LSD instances.

events

discovery.on('peer', (peer, source) => {})

Emitted whenever a new peer is discovered. Source is either 'tracker', 'dht', or 'lsd' based on peer source.

In node, peer is a string in the form ip:port, e.g. 12.34.56.78:4000.

In the browser, peer is an instance of simple-peer, a small wrapper around a WebRTC peer connection.

discovery.on('dhtAnnounce', () => {})

Emitted whenever an announce message has been sent to the DHT.

discovery.on('warning', err => {})

Emitted when there is a non-fatal DHT, tracker, or LSD error. For example, an inaccessible tracker server would be considered a warning. Useful for logging.

discovery.on('error', err => {})

Emitted when there is a fatal, DHT, tracker, or LSD error. This is unrecoverable and the discovery object will be destroyed if this event is emitted.

license

MIT. Copyright (c) Feross Aboukhadijeh and WebTorrent, LLC.