WebTorrent Documentation

WebTorrent is a streaming torrent client for Node.js and the web. WebTorrent provides the same API in both environments.

To use WebTorrent in the browser, WebRTC support is required (Chrome, Firefox, Opera, Safari).

Install

npm install webtorrent

Quick Example

const client = new WebTorrent()

const torrentId = 'magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel&tr=udp%3A%2F%2Fexplodie.org%3A6969&tr=udp%3A%2F%2Ftracker.coppersurfer.tk%3A6969&tr=udp%3A%2F%2Ftracker.empire-js.us%3A1337&tr=udp%3A%2F%2Ftracker.leechers-paradise.org%3A6969&tr=udp%3A%2F%2Ftracker.opentrackr.org%3A1337&tr=wss%3A%2F%2Ftracker.btorrent.xyz&tr=wss%3A%2F%2Ftracker.fastcast.nz&tr=wss%3A%2F%2Ftracker.openwebtorrent.com&ws=https%3A%2F%2Fwebtorrent.io%2Ftorrents%2F&xs=https%3A%2F%2Fwebtorrent.io%2Ftorrents%2Fsintel.torrent'

// see tutorials.md for a full example of streaming media using service workers
navigator.serviceWorker.register('sw.min.js')
const controller = await navigator.serviceWorker.ready
client.createServer({ controller })

client.add(torrentId, torrent => {
  // Torrents can contain many files. Let's use the .mp4 file
  const file = torrent.files.find(file => {
    return file.name.endsWith('.mp4')
  })

  // Display the file by adding it to the DOM. Supports video, audio, image, etc. files
  file.streamTo(document.querySelector('video'))
})

WebTorrent API

`WebTorrent.WEBRTC_SUPPORT`

Is WebRTC natively supported in the environment?

if (WebTorrent.WEBRTC_SUPPORT) {
  // WebRTC is supported
} else {
  // Use a fallback
}

`client = new WebTorrent([opts])`

Create a new WebTorrent instance.

If opts is specified, then the default options (shown below) will be overridden.

{
  maxConns: Number,        // Max number of connections per torrent (default=55)
  nodeId: String|Uint8Array,   // DHT protocol node ID (default=randomly generated)
  peerId: String|Uint8Array,   // Wire protocol peer ID (default=randomly generated)
  tracker: Boolean|Object, // Enable trackers (default=true), or options object for Tracker
  dht: Boolean|Object,     // Enable DHT (default=true), or options object for DHT
  lsd: Boolean,            // Enable BEP14 local service discovery (default=true)
  utPex: Boolean,          // Enable BEP11 Peer Exchange (default=true)
  natUpnp: Boolean | String, // Enable NAT port mapping via NAT-UPnP (default=true). NodeJS only
  natPmp: Boolean,         // Enable NAT port mapping via NAT-PMP (default=true). NodeJS only.
  webSeeds: Boolean,       // Enable BEP19 web seeds (default=true)
  utp: Boolean,            // Enable BEP29 uTorrent transport protocol (default=true)
  blocklist: Array|String, // List of IP's to block
  downloadLimit: Number,   // Max download speed (bytes/sec) over all torrents (default=-1)
  uploadLimit: Number,     // Max upload speed (bytes/sec) over all torrents (default=-1)
}

For possible values of opts.dht see the bittorrent-dht documentation.

For possible values of opts.tracker see the bittorrent-tracker documentation.

For possible values of opts.blocklist see the load-ip-set documentation.

For opts.natUpnp and opts.natPmp, if both are set to true, PMP will be attempted first, then fallback to UPNP. NodeJS only.

For opts.natUpnp, if set to true, a temporary mapping is used, if set to permanent, a permanent TTL will be used for UPNP if the router only supports permanent leases. NodeJS only.

For downloadLimit and uploadLimit the possible values can be:

> 0. The client will set the throttle at that speed
0. The client will block any data from being downloaded or uploaded
-1. The client will is disable the throttling and use the whole bandwidth available

`client.add(torrentId, [opts], [function ontorrent (torrent) {}])`

Start downloading a new torrent.

torrentId can be one of:

magnet uri (string)
torrent file (Uint8Array)
info hash (hex string or Uint8Array)
parsed torrent (from parse-torrent)
http/https url to a torrent file (string)
filesystem path to a torrent file (string) (Node.js only)

If opts is specified, then the default options (shown below) will be overridden.

{
  announce: [String],        // Torrent trackers to use (added to list in .torrent or magnet uri)
  getAnnounceOpts: Function, // Custom callback to allow sending extra parameters to the tracker
  urlList: [String],         // Array of web seeds
  maxWebConns: Number,       // Max number of simultaneous connections per web seed [default=4]
  path: String,              // Folder to download files to (default=`/tmp/webtorrent/`)
  private: Boolean,          // If true, client will not share the hash with the DHT nor with PEX (default is the privacy of the parsed torrent)
  store: Function,           // Custom chunk store (must follow [abstract-chunk-store](https://www.npmjs.com/package/abstract-chunk-store) API)
  destroyStoreOnDestroy: Boolean, // If truthy, client will delete the torrent's chunk store (e.g. files on disk) when the torrent is destroyed
  storeCacheSlots: Number,   // Number of chunk store entries (torrent pieces) to cache in memory [default=20]; 0 to disable caching
  storeOpts: Object,         // Custom options passed to the store
  addUID: Boolean,           // (Node.js only) If true, the torrent will be stored in it's infoHash folder to prevent file name collisions (default=false)
  skipVerify: Boolean,       // If true, client will skip verification of pieces for existing store and assume it's correct
  preloadedStore: Function,  // Custom, pre-loaded chunk store (must follow [abstract-chunk-store](https://www.npmjs.com/package/abstract-chunk-store) API)
  strategy: String,          // Piece selection strategy, `rarest` or `sequential`(defaut=`sequential`)
  noPeersIntervalTime: Number, // The amount of time (in seconds) to wait between each check of the `noPeers` event (default=30)
  paused: Boolean,           // If true, create the torrent in a paused state (default=false)
  deselect: Boolean,         // If true, create the torrent with no pieces selected (default=false)
  alwaysChokeSeeders: Boolean // If true, client will automatically choke seeders if it's seeding. (default=true)
}

If ontorrent is specified, then it will be called when this torrent is ready to be used (i.e. metadata is available). Note: this is distinct from the 'torrent' event which will fire for all torrents.

If you want access to the torrent object immediately in order to listen to events as the metadata is fetched from the network, then use the return value of client.add. If you just want the file data, then use ontorrent or the 'torrent' event.

If you provide opts.store, it will be called as opts.store(chunkLength, storeOpts) with:

storeOpts - custom storeOpts specified in opts
storeOpts.length - size of all the files in the torrent
storeOpts.files - an array of torrent file objects
storeOpts.torrent - the torrent instance being stored
storeOpts.path - path to the store, based on opts.path
storeOpts.name - the info hash of the torrent instance being stored
storeOpts.addUID - boolean which tells the store if it should include an UID in it's file paths
storeOpts.rootDir - (browser only) FileSystemDirectoryHandle - if supported by the browser, allows the user to specify a custom directory to stores the files in, retaining the torrent's folder and file structure

Note (browser only): If you don't want to retain data across sessions, make sure to manually destroy the torrent store when the page closes (More on how below). This has to happen on the beforeunload event at latest, in order for the data to be removed. About page lifecycles.

Note: Downloading a torrent automatically seeds it, making it available for download by other peers.

`client.seed(input, [opts], [function onseed (torrent) {}])`

Start seeding a new torrent.

input can be any of the following:

filesystem path to file or folder (string) (Node.js only)
W3C FileList object (basically an array of File objects) (browser only)
W3C File/Blob object (from an <input> or drag and drop)
typed array or array of numbers
Node Buffer object
Node Readable stream object

Or, an array of of any of those values.

If opts is specified, it should contain the following types of options:

options for create-torrent (to allow configuration of the .torrent file that is created)
options for client.add (see above)

If onseed is specified, it will be called when the client has begun seeding the file.

Note: Every torrent is required to have a name. If one is not explicitly provided through opts.name, one will be determined automatically using the following logic:

If all files share a common path prefix, that will be used. For example, if all file paths start with /imgs/ the torrent name will be imgs.
Otherwise, the first file that has a name will determine the torrent name. For example, if the first file is /foo/bar/baz.txt, the torrent name will be baz.txt.
If no files have names (say that all files are Uint8Array or Stream objects), then a name like "Unnamed Torrent " will be generated.

Note: Every file is required to have a name. For filesystem paths or W3C File objects, the name is included in the object. For Uint8Array or Readable stream types, a name property can be set on the object, like this:

const buf = new Uint8Array('Some file content')
buf.name = 'Some file name'
client.seed(buf, cb)

`client.on('torrent', function (torrent) {})`

Emitted when a torrent is ready to be used (i.e. metadata is available and store is ready). See the torrent section for more info on what methods a torrent has.

`client.on('error', function (err) {})`

Emitted when the client encounters a fatal error. The client is automatically destroyed and all torrents are removed and cleaned up when this occurs.

Always listen for the 'error' event.

`await client.remove(torrentId, [opts], [function callback (err) {}])`

Remove a torrent from the client. Destroy all connections to peers and delete all saved file metadata.

If opts.destroyStore is specified, it will override opts.destroyStoreOnDestroy passed when the torrent was added. If truthy, store.destroy() will be called, which will delete the torrent's files from the disk.

If callback is provided, it will be called when the torrent is fully destroyed, i.e. all open sockets are closed, and the storage is either closed or destroyed.

`client.destroy([function callback (err) {}])`

Destroy the client, including all torrents and connections to peers. If callback is specified, it will be called when the client has gracefully closed.

`client.torrents[...]`

An array of all torrents in the client.

`await client.get(torrentId)`

Returns a promise which resolves the torrent with the given torrentId. Convenience method. Easier than searching through the client.torrents array. Returns null if no matching torrent found.

`client.downloadSpeed`

Total download speed for all torrents, in bytes/sec.

`client.uploadSpeed`

Total upload speed for all torrents, in bytes/sec.

`client.progress`

Total download progress for all active torrents, from 0 to 1.

`client.ratio`

Aggregate "seed ratio" for all torrents (uploaded / downloaded).

`client.throttleDownload(rate)`

Sets the maximum speed at which the client downloads the torrents, in bytes/sec.

rate must be bigger or equal than zero, or -1 to disable the download throttle and use the whole bandwidth of the connection.

`client.throttleUpload(rate)`

Sets the maximum speed at which the client uploads the torrents, in bytes/sec.

rate must be bigger or equal than zero, or -1 to disable the upload throttle and use the whole bandwidth of the connection.

`client.createServer([opts], force)`

Create an http server to serve the contents of this torrent, dynamically fetching the needed torrent pieces to satisfy http requests. Range requests are supported. If opts is specified, it can have the following properties:

{
  origin: String // Allow requests from specific origin. `false` for same-origin. [default: '*']
  hostname: String // If specified, only allow requests whose `Host` header matches this hostname. Note that you should not specify the port since this is automatically determined by the server. Ex: `localhost` [default: `undefined`]. NodeJS only.
  path: String // Allows to overwrite the default `/webtorrent` base path. [default: '/webtorrent']. NodeJS only.
  controller: ServiceWorkerRegistration // Accepts an existing service worker registration [await navigator.serviceWorker.getRegistration()]. Browser only. Required!
}

If force is specified, it can force WebTorrent to use a specific implementation for enviorments which run both Node and Browser like NW.js or Electron. Allowed values:

'browser' || 'node'

Visiting the root of the server / won't show anything. Visiting /webtorrent/ will list all torrents. Access individual torrents at /webtorrent/<infohash> where infohash is the hash of the torrent. To acceess individual files, go to /webtorrent/<infoHash>/<filepath> where filepath is the file's path in the torrent.

Here is a usage example for Node.js:

const client = new WebTorrent()
const magnetURI = 'magnet: ...'

const instance = client.createServer()
instance.server.listen(0) // start the server listening to a port
// 0 automatically finds an open port instead of forcing a potentially used one
client.add(magnetURI, torrent => {
  // create HTTP server for this torrent

  const url = torrent.files[0].streamURL
  console.log(url)
  // visit http://localhost:<port>/webtorrent/ to see a list of torrents

  // access individual torrents at http://localhost:<port>/webtorrent/<infoHash> where infoHash is the hash of the torrent
})

// later, cleanup...
instance.close()
client.destroy()

In browser needs either this worker to be used, or have this functionality implemented.

Here is a user example for browser:

const client = new WebTorrent()
const magnetURI = 'magnet: ...'
const player = document.querySelector('video')

function download (instance) {
  client.add(magnetURI, torrent => {
    const url = torrent.files[0].streamURL
    console.log(url)
    // visit <origin>/webtorrent/ to see a list of torrents, where origin is the worker registration scope.

    // access individual torrents at /webtorrent/<infoHash> where infoHash is the hash of the torrent
  })
}
navigator.serviceWorker.register('./sw.min.js', { scope: './' }).then(reg => {
  const worker = reg.active || reg.waiting || reg.installing
  function checkState (worker) {
    return worker.state === 'activated' && download(client.createServer({ controller: reg }))
  }
  if (!checkState(worker)) {
    worker.addEventListener('statechange', ({ target }) => checkState(target))
  }
})

// later, cleanup...
client._server.close()
client.destroy()

Needs either this worker to be used, or have this functionality implemented.

Torrent API

`torrent.name`

Name of the torrent (string).

`torrent.infoHash`

Info hash of the torrent (string).

`torrent.magnetURI`

Magnet URI of the torrent (string).

`torrent.torrentFile`

.torrent file of the torrent (Uint8Array).

`torrent.torrentFileBlob`

.torrent file of the torrent (Blob). Useful for creating Blob URLs via URL.createObjectURL(blob)

`torrent.announce[...]`

Array of all tracker servers. Each announce is an URL (string).

`torrent.files[...]`

Array of all files in the torrent. See documentation for File below to learn what methods/properties files have.

`torrent.pieces[...]`

Array of all pieces in the torrent. See documentation for Piece below to learn what properties pieces have. Some pieces can be null.

`torrent.pieceLength`

Length in bytes of every piece but the last one.

`torrent.lastPieceLength`

Length in bytes of the last piece (<= of torrent.pieceLength).

`torrent.timeRemaining`

Time remaining for download to complete (in milliseconds).

`torrent.received`

Total bytes received from peers (including invalid data).

`torrent.downloaded`

Total verified bytes received from peers.

`torrent.uploaded`

Total bytes uploaded to peers.

`torrent.downloadSpeed`

Torrent download speed, in bytes/sec.

`torrent.uploadSpeed`

Torrent upload speed, in bytes/sec.

`torrent.progress`

Torrent download progress, from 0 to 1.

`torrent.ratio`

Torrent "seed ratio" (uploaded / downloaded).

`torrent.numPeers`

Number of peers in the torrent swarm.

`torrent.maxWebConns`

Max number of simultaneous connections per web seed, as passed in the options.

`torrent.path`

Torrent download location.

`torrent.ready`

True when the torrent is ready to be used (i.e. metadata is available and store is ready).

`torrent.paused`

True when the torrent has stopped connecting to new peers. Note that this does not pause new incoming connections, nor does it pause the streams of existing connections or their wires.

`torrent.done`

True when all the torrent files have been downloaded.

`torrent.length`

Sum of the files length (in bytes).

`torrent.created`

Date of creation of the torrent (as a Date object).

`torrent.createdBy`

Author of the torrent (string).

`torrent.comment`

A comment optionnaly set by the author (string).

`torrent.destroy([opts], [callback])`

Remove the torrent from its client. Destroy all connections to peers and delete all saved file metadata.

If opts.destroyStore is specified, it will override opts.destroyStoreOnDestroy passed when the torrent was added. If truthy, store.destroy() will be called, which will delete the torrent's files from the disk.

If callback is provided, it will be called when the torrent is fully destroyed, i.e. all open sockets are closed, and the storage is either closed or destroyed.

`torrent.addPeer(peer)`

Add a peer to the torrent swarm. This is advanced functionality. Normally, you should not need to call torrent.addPeer() manually. WebTorrent will automatically find peers using the tracker servers or DHT. This is just for manually adding a peer to the client.

This method should not be called until the infoHash event has been emitted.

Returns true if peer was added, false if peer was blocked by the loaded blocklist.

The peer argument must be an address string in the format 12.34.56.78:4444 (for normal TCP/uTP peers), or a simple-peer instance (for WebRTC peers).

`torrent.addWebSeed(urlOrConn)`

Add a web seed to the torrent swarm. For more information on BitTorrent web seeds, see BEP19.

In the browser, web seed servers must have proper CORS (Cross-origin resource sharing) headers so that data can be fetched across domain.

The urlOrConn argument is either the web seed URL, or an object that provides a custom web seed implementation. A custom conn object is a duplex stream that speaks the bittorrent wire protocol and pretends to be a remote peer. It must have a connId property that uniquely identifies the custom web seed.

`torrent.removePeer(peer)`

Remove a peer from the torrent swarm. This is advanced functionality. Normally, you should not need to call torrent.removePeer() manually. WebTorrent will automatically remove peers from the torrent swarm when they're slow or don't have pieces that are needed.

The peer argument should be an address (i.e. "ip:port" string), a peer id (hex string), or simple-peer instance.

`torrent.select(start, end, [priority], [notify])`

Selects a range of pieces to prioritize starting with start and ending with end (both inclusive) at the given priority. notify is an optional callback to be called when the selection is updated with new data.

`torrent.deselect(start, end)`

Deprioritizes a range of previously selected pieces.

`torrent.critical(start, end)`

Marks a range of pieces as critical priority to be downloaded ASAP. From start to end (both inclusive).

`torrent.pause()`

Temporarily stop connecting to new peers. Note that this does not pause new incoming connections, nor does it pause the streams of existing connections or their wires.

`torrent.resume()`

Resume connecting to new peers.

`torrent.rescanFiles([function callback (err) {}])`

Verify the hashes of all pieces in the store and update the bitfield for any new valid pieces. Useful if data has been added to the store outside WebTorrent, e.g. if another process puts a valid file in the right place. Once the scan is complete, callback(null) will be called (if provided), unless the torrent was destroyed during the scan, in which case callback will be called with an error.

`torrent.on('infoHash', function () {})`

Emitted when the info hash of the torrent has been determined.

`torrent.on('metadata', function () {})`

Emitted when the metadata of the torrent has been determined. This includes the full contents of the .torrent file, including list of files, torrent length, piece hashes, piece length, etc.

`torrent.on('ready', function () {})`

Emitted when the torrent is ready to be used (i.e. metadata is available and store is ready).

`torrent.on('warning', function (err) {})`

Emitted when there is a warning. This is purely informational and it is not necessary to listen to this event, but it may aid in debugging.

`torrent.on('error', function (err) {})`

Emitted when the torrent encounters a fatal error. The torrent is automatically destroyed and removed from the client when this occurs.

Note: Torrent errors are emitted at torrent.on('error'). If there are no 'error' event handlers on the torrent instance, then the error will be emitted at client.on('error'). This prevents throwing an uncaught exception (unhandled 'error' event), but it makes it impossible to distinguish client errors versus torrent errors. Torrent errors are not fatal, and the client is still usable afterwards. Therefore, always listen for errors in both places (client.on('error') and torrent.on('error')).

`torrent.on('done', function () {})`

Emitted when all the torrent files have been downloaded.

Here is a usage example:

torrent.on('done', () => {
  console.log('torrent finished downloading')
  for (const file of torrent.files) { 
    // do something with file
  }
})

`torrent.on('download', function (bytes) {})`

Emitted whenever data is downloaded. Useful for reporting the current torrent status, for instance:

torrent.on('download', bytes => {
  console.log('just downloaded: ' + bytes)
  console.log('total downloaded: ' + torrent.downloaded)
  console.log('download speed: ' + torrent.downloadSpeed)
  console.log('progress: ' + torrent.progress)
})

`torrent.on('upload', function (bytes) {})`

Emitted whenever data is uploaded. Useful for reporting the current torrent status.

`torrent.on('wire', function (wire) {})`

Emitted whenever a new peer is connected for this torrent. wire is an instance of bittorrent-protocol, which is a node.js-style duplex stream to the remote peer. This event can be used to specify custom BitTorrent protocol extensions.

Here is a usage example:

import MyExtension from './my-extension'

torrent1.on('wire', (wire, addr) => {
  console.log('connected to peer with address ' + addr)
  wire.use(MyExtension)
})

See the bittorrent-protocol extension api docs for more information on how to define a protocol extension.

`torrent.on('noPeers', function (announceType) {})`

Emitted every couple of seconds when no peers have been found. announceType is either 'tracker', 'dht', 'lsd', or 'ut_pex' depending on which announce occurred to trigger this event. Note that if you're attempting to discover peers from a tracker, a DHT, a LSD, and PEX you'll see this event separately for each.

`torrent.on('verified', function (index) {})`

Emitted every time a piece is verified, the value of the event is the index of the verified piece.

File API

Webtorrent Files closely mimic W3C Files/Blobs except for slice where instead you pass the offsets as objects to the arrayBuffer/stream/createReadStream functions.

`file.name`

File name, as specified by the torrent. Example: 'some-filename.txt'

`file.path`

File path, as specified by the torrent. Example: 'some-folder/some-filename.txt'

`file.length` or `file.size`

File length (in bytes), as specified by the torrent. Example: 12345

`file.type`

Mime type of the file, falls back to application/octet-stream if the type is not recognized.

`file.downloaded`

Total verified bytes received from peers, for this file.

`file.progress`

File download progress, from 0 to 1.

`file.select([priority])`

Selects the file to be downloaded, at the given priority. Useful if you know you need the file at a later stage.

`file.deselect()`

Deselects the file's specific priority, which means it won't be downloaded unless someone creates a stream for it.

*Note: This method is currently not working as expected, see dcposch answer on #164 for a nice work around solution.

`stream = file.createReadStream([opts])`

Create a readable stream to the file. Pieces needed by the stream will be prioritized highly and fetched from the swarm first.

You can pass opts to stream only a slice of a file.

{
  start: startByte,
  end: endByte
}

Both start and end are inclusive.

`stream = file.stream(opts)`

Create a W3C ReadableStream to the file. Pieces needed by the stream will be prioritized highly and fetched from the swarm first.

You can pass opts to stream only a slice of a file.

{
  start: startByte,
  end: endByte
}

Both start and end are inclusive.

`iterator = file[Symbol.asyncIterator]`

Create an async iterator to the file. Pieces needed by the stream will be prioritized highly and fetched from the swarm first.

You can pass opts to iterate only a slice of a file.

{
  start: startByte,
  end: endByte
}

Both start and end are inclusive.

Example:

for await (const chunk of file) {
  // do something with chunk
}

`arrayBuffer = await file.arrayBuffer(opts)`

Get the file contents as a ArrayBuffer.

You can pass opts to get only a part of an ArrayBuffer.

{
  start: startByte,
  end: endByte
}

const data = await file.arrayBuffer()
console.log(data) // ArrayBuffer { [Uint8Contents]: <00 62 00 01>, byteLength: 4 }

`blob = await file.blob(opts)`

Get a W3C Blob object which contains the file data.

Useful for creating Blob URLs via URL.createObjectURL(blob).

You can pass opts to get only a part of an Blob.

{
  start: startByte,
  end: endByte
}

`file.streamTo(elem)` (browser only)

Requires client.createServer to be ran beforehand. Sets the element source to the file's streaming URL. Supports streaming, seeking and all browser codecs and containers.

Support table:

Containers	Chromium	Mobile Chromium	Edge	Chrome	Firefox
3g2	✓	✓	✓	✓	✓
3gp	✓	✓	✓	✓	✘
avi	✘	✘	✘	✘	✘
m2ts	✘	✘	✓**	✘	✘
m4v etc.	✓*	✓*	✓*	✓*	✓*
mp4	✓	✓	✓	✓	✓
mpeg	✘	✘	✘	✘	✘
mov	✓	✓	✓	✓	✓
ogm ogv	✓	✓	✓	✓	✓
webm	✓	✓	✓	✓	✓
mkv	✓	✓	✓	✓	✘

* Container might be supported, but the container's codecs might not be.
** Documented as working, but can't reproduce.

Video Codecs	Chromium	Mobile Chromium	Edge	Chrome	Firefox
AV1	✓	✓	✓	✓	✓
H.263	✘	✘	✘	✘	✘
H.264	✓	✓	✓	✓	✓
H.265	✘	✘	✓*	✓	✘
MPEG-2/4	✘	✘	✘	✘	✘
Theora	✓	✘	✓	✓	✓
VP8/9	✓	✓	✓	✓	✓

* Requires MSStore extension which you can get by opening this link ms-windows-store://pdp/?ProductId=9n4wgh0z6vhq while using Edge.

Audio Codecs	Chromium	Mobile Chromium	Edge	Chrome	Firefox
AAC	✓	✓	✓	✓	✓
AC3	✘	✘	✓	✘	✘
DTS	✘	✘	✘	✘	✘
EAC3	✘	✘	✓	✘	✘
FLAC	✓	✓*	✓	✓	✓
MP3	✓	✓	✓	✓	✓
Opus	✓	✓	✓	✓	✓
TrueHD	✘	✘	✘	✘	✘
Vorbis	✓	✓	✓	✓	✓*

* Might not work in some video containers.

Since container and codec support is browser dependent these values might change over time.

`file.streamURL`

Requires client.createServer to be ran beforehand.

Returns the URL of the file which is recognized by the HTTP server.

This method is useful both for servers which run WebTorrent or client apps. A few examples:

const url = file.streamURL

// create download link
if (err) throw err
const a = document.createElement('a')
a.target = "_blank"
a.href = url
a.textContent = 'Download ' + file.name
document.body.append(a)

// render an image on a canvas
const canvas = document.getElementById('canvas')
const ctx = canvas.getContext('2d')
const img = new Image()
const loaded = new Promise(resolve => img.onload = resolve)
img.src = url
await loaded
ctx.drawImage(img)

// send the file URL to another device on the network which can then display the file remotely [nodejs only]
import networkAddress from 'network-address'

const networkURL = `http://${networkAddress()}:${client._server.port}${url}`
sendRemote(networkURL)

`file.on('stream', function ({ stream, file, req }, function pipeCallback) {})`

This is advanced functionality.

Emitted every time when the HTTP server creates a new read stream. For example every time the user seeks a video. This allows you to find out what parts of the file the browser is requesting, and how it's requesting them. Additionally it allows you to manipulate the data that's being streamed.

Yields an object with 3 values and a function:

object - information about the request,
- stream - a readable stream which the user can manipulate,
- file - the file object that's being streamed,
- req - all the request information which the browser made when requesting the data.
function - if you pipe the stream, use this function to callback the piped stream synchronously! Otherwise the playback is likely to break.

Example usage:

file.on('stream', ({ stream, file, req }, cb) => {
  if (req.destination === 'audio' && file.name.endsWith('.dts')) {
    const transcoder = new SomeAudioTranscoder()
    cb(transcoder)
    // do other things
  }
})

`file.on('iterator', function ({ stream, file, req }, function transformCallback) {})`

This is advanced functionality.

Same as with the stream event this is emitted by the HTTP server when it creates an async iterator for the file's data. This is used for very low-level manipulation of the incoming data and they way it's generated for example you could potentially accelerate how fast and how much data is pulled from the torrent.

Yields an object with 3 values and a function:

object - information about the request,
- iterator - an async iterator which the user can manipulate,
- file - the file object that's being streamed,
- req - all the request information which the browser made when requesting the data.
function - if you wish to transform the iterator, use this function to callback the transformed iterator synchronously! Otherwise the playback is likely to break.

Example usage:

import par from 'it-parallel'

file.on('iterator', ({ iterator, file, req }, cb) => {
  const transform = par(iterator, { concurrency: 5, ordered: true })
  cb(transform)
})

`file.includes(piece)`

Check if the piece number contains this file's data.

`file.on('done', function () {})`

Emitted when the file has been downloaded.

Piece API

`piece.length`

Piece length (in bytes). Example: 12345

`piece.missing`

Piece missing length (in bytes). Example: 100

Wire API

`wire.peerId`

Remote peer id (hex string)

`wire.type`

Connection type ('webrtc', 'tcpIncoming', 'tcpOutgoing', 'utpIncoming', 'utpOutgoing', 'webSeed')

`wire.uploaded`

Total bytes uploaded to peer.

`wire.downloaded`

Total bytes downloaded from peer.

`wire.uploadSpeed`

Peer upload speed, in bytes/sec.

`wire.downloadSpeed`

Peer download speed, in bytes/sec.

`wire.remoteAddress`

Peer's remote address. Only exists for tcp/utp peers.

`wire.remotePort`

Peer's remote port. Only exists for tcp/utp peers.

`wire.destroy()`

Close the connection with the peer. This however doesn't prevent the peer from simply re-connecting.

Files

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WebTorrent Documentation

Install

Quick Example

WebTorrent API

WebTorrent.WEBRTC_SUPPORT

client = new WebTorrent([opts])

client.add(torrentId, [opts], [function ontorrent (torrent) {}])

client.seed(input, [opts], [function onseed (torrent) {}])

client.on('torrent', function (torrent) {})

client.on('error', function (err) {})

await client.remove(torrentId, [opts], [function callback (err) {}])

client.destroy([function callback (err) {}])

client.torrents[...]

await client.get(torrentId)

client.downloadSpeed

client.uploadSpeed

client.progress

client.ratio

client.throttleDownload(rate)

client.throttleUpload(rate)

client.createServer([opts], force)

Torrent API

torrent.name

torrent.infoHash

torrent.magnetURI

torrent.torrentFile

torrent.torrentFileBlob

torrent.announce[...]

torrent.files[...]

torrent.pieces[...]

torrent.pieceLength

torrent.lastPieceLength

torrent.timeRemaining

torrent.received

torrent.downloaded

torrent.uploaded

torrent.downloadSpeed

torrent.uploadSpeed

torrent.progress

torrent.ratio

torrent.numPeers

torrent.maxWebConns

torrent.path

torrent.ready

torrent.paused

torrent.done

torrent.length

torrent.created

torrent.createdBy

torrent.comment

torrent.destroy([opts], [callback])

torrent.addPeer(peer)

torrent.addWebSeed(urlOrConn)

torrent.removePeer(peer)

torrent.select(start, end, [priority], [notify])

torrent.deselect(start, end)

torrent.critical(start, end)

torrent.pause()

torrent.resume()

torrent.rescanFiles([function callback (err) {}])

torrent.on('infoHash', function () {})

torrent.on('metadata', function () {})

torrent.on('ready', function () {})

torrent.on('warning', function (err) {})

torrent.on('error', function (err) {})

torrent.on('done', function () {})

torrent.on('download', function (bytes) {})

torrent.on('upload', function (bytes) {})

torrent.on('wire', function (wire) {})

torrent.on('noPeers', function (announceType) {})

torrent.on('verified', function (index) {})

File API

file.name

file.path

`WebTorrent.WEBRTC_SUPPORT`

`client = new WebTorrent([opts])`

`client.add(torrentId, [opts], [function ontorrent (torrent) {}])`

`client.seed(input, [opts], [function onseed (torrent) {}])`

`client.on('torrent', function (torrent) {})`

`client.on('error', function (err) {})`

`await client.remove(torrentId, [opts], [function callback (err) {}])`

`client.destroy([function callback (err) {}])`

`client.torrents[...]`

`await client.get(torrentId)`

`client.downloadSpeed`

`client.uploadSpeed`

`client.progress`

`client.ratio`

`client.throttleDownload(rate)`

`client.throttleUpload(rate)`

`client.createServer([opts], force)`

`torrent.name`

`torrent.infoHash`

`torrent.magnetURI`

`torrent.torrentFile`

`torrent.torrentFileBlob`

`torrent.announce[...]`

`torrent.files[...]`

`torrent.pieces[...]`

`torrent.pieceLength`

`torrent.lastPieceLength`

`torrent.timeRemaining`

`torrent.received`

`torrent.downloaded`

`torrent.uploaded`

`torrent.downloadSpeed`

`torrent.uploadSpeed`

`torrent.progress`

`torrent.ratio`

`torrent.numPeers`

`torrent.maxWebConns`

`torrent.path`

`torrent.ready`

`torrent.paused`

`torrent.done`

`torrent.length`

`torrent.created`

`torrent.createdBy`

`torrent.comment`

`torrent.destroy([opts], [callback])`

`torrent.addPeer(peer)`

`torrent.addWebSeed(urlOrConn)`

`torrent.removePeer(peer)`

`torrent.select(start, end, [priority], [notify])`

`torrent.deselect(start, end)`

`torrent.critical(start, end)`

`torrent.pause()`

`torrent.resume()`

`torrent.rescanFiles([function callback (err) {}])`

`torrent.on('infoHash', function () {})`

`torrent.on('metadata', function () {})`

`torrent.on('ready', function () {})`

`torrent.on('warning', function (err) {})`

`torrent.on('error', function (err) {})`

`torrent.on('done', function () {})`

`torrent.on('download', function (bytes) {})`

`torrent.on('upload', function (bytes) {})`

`torrent.on('wire', function (wire) {})`

`torrent.on('noPeers', function (announceType) {})`

`torrent.on('verified', function (index) {})`

`file.name`

`file.path`

`file.length` or `file.size`

`file.type`

`file.downloaded`

`file.progress`

`file.select([priority])`

`file.deselect()`

`stream = file.createReadStream([opts])`

`stream = file.stream(opts)`

`iterator = file[Symbol.asyncIterator]`

`arrayBuffer = await file.arrayBuffer(opts)`

`blob = await file.blob(opts)`

`file.streamTo(elem)` (browser only)