LioWebRTC
An Electron-compatible, event-based WebRTC library that makes it easy to embed peer to peer communication into React components.
LioWebRTC was built on SimpleWebRTC, and modified to be compatible with React, JSX, and Electron.
Click here to see a chatroom demo app built with React and LioWebRTC.
Usage
Installation
yarn add liowebrtc
// Or
npm i liowebrtc
Import LioWebRTC
import LioWebRTC from 'liowebrtc';
Create LioWebRTC instance
const webrtc = new LioWebRTC({
// The local video reference set within your render function, or the element's ID
localVideoEl: 'localVid',
// Immediately request camera and mic access.
autoRequestMedia: true,
// Displays events emitted by the webrtc object in the console.
debug: true,
// Set this to true if you want to disable video/audio channels, and only enable data channel.
dataOnly: false,
// The url for your signaling server
url: 'https://sandbox.simplewebrtc.com:443/',
});
Join a room once it's ready
webrtc.on('readyToCall', () => {
// Create or join a room with any name
webrtc.joinRoom('your room name');
});
Emitting to the hive
Sometimes a peer wants to let every other peer in the room to know about something. This can be accomplished with
shout(messageType, payload)
webrtc.shout('taskCompleted', { success: true, id: '137' });
Now for the recipients, handle the peer event with a listener:
webrtc.on('receivedPeerData', (type, data, peer) => {
if (type === 'taskCompleted' && data.success) {
console.log(`Peer ${peer.id} completed task ${data.id}`);
}
});
Communicating with a single peer
Sometimes a peer only wants to send data directly to another peer. This can be accomplished with
whisper(peer, messageType, payload)
webrtc.whisper(peer, 'directMessage', { msg: 'Hello world!' });
Receiving the message is the same as handling a peer event:
webrtc.on('receivedPeerData', (type, data, peer) => {
if (type === 'directMessage') console.log(`Peer ${peer.id} says: ${data.msg}`);
});
Live-syncing state
componentDidUpdate(prevProps, prevState) {
if (this.state.position !== prevState.position) {
this.webrtc.shout('stateUpdate', this.state);
}
}
this.webrtc.on('receivedPeerData', (type, state, peer) => {
if (type === 'stateUpdate') this.setState({ peerState: state });
});
All communications via shout/whisper are sent over the default data channel and emitted by the LioWebRTC instance as events. You can create your own custom listeners suited for whatever purpose you'd like.
Example
P2P Video Chat Component
import React, { Component } from 'react';
import LioWebRTC from 'liowebrtc';
import 'attachMediaStream' from 'attachmediastream';
class Party extends Component {
constructor(props) {
super(props);
this.state = {
nick: this.props.nick,
peers: [],
roomID: `party-${this.props.roomName}`,
muted: false,
camPaused: false
};
this.remoteVideos = {};
}
componentDidMount() {
this.webrtc = new LioWebRTC({
// The url for your signaling server
url: 'https://sandbox.simplewebrtc.com:443/',
// The local video reference set within your render function
localVideoEl: this.localVid,
// Immediately request camera access
autoRequestMedia: true,
// Optional: The nickname of the peer in the room
nick: this.state.nick,
});
this.webrtc.on('videoAdded', this.addVideo);
this.webrtc.on('videoRemoved', this.removeVideo);
this.webrtc.on('readyToCall', this.readyToCall);
this.webrtc.on('iceFailed', this.handleConnectionError);
this.webrtc.on('connectivityError', this.handleConnectionError);
}
addVideo = (stream, peer) => {
this.setState({
peers: [...this.state.peers, peer]
}, () => {
attachMediaStream(stream, this.remoteVideos[peer.id]);
});
}
removeVideo = (video, peer) => {
this.setState({
peers: this.state.peers.filter(p => p.id)
});
}
handleConnectionError = (peer) => {
const pc = peer.pc;
console.log('had local relay candidate', pc.hadLocalRelayCandidate);
console.log('had remote relay candidate', pc.hadRemoteRelayCandidate);
}
readyToCall = () => {
// Starts the process of joining a room.
this.webrtc.joinRoom(this.state.roomID, (err, desc) => {
});
}
// Show fellow peers in the room
generateRemotes = () => this.state.peers.map((p) => (
<div key={p.id}>
<div id={`container_${this.webrtc.getDomId(p)}`}>
<video
key={this.webrtc.getDomId(p)}
// Important: The video element needs both an id and ref
id={this.webrtc.getDomId(p)}
ref={(v) => this.remoteVideos[p.id] = v}
/>
</div>
<p>{p.nick}</p>
</div>
));
disconnect = () => {
this.webrtc.stopLocalVideo();
this.webrtc.leaveRoom();
this.webrtc.disconnect();
}
componentWillUnmount() {
this.disconnect();
}
render() {
return (
<div>
<div>
<video
// Important: The local video element needs to have both an ID and ref
id="localVideo"
ref={(vid) => { this.localVid = vid; }}
/>
<p>{this.state.nick}</p>
</div>
<div id="remoteVideos">
{this.generateRemotes()}
</div>
</div>
);
}
}
export default Party;
API
Constructor
new LioWebRTC(options)
-
object options
-
string url
- url for signaling server. -
bool debug
- optional flag to set the instance to debug mode -
[string|DomElement] localVideoEl
- ID or Element to contain the local video element -
bool autoRequestMedia
- optional(=true) option to automatically request user media. Usetrue
to request automatically, orfalse
to request media later withstartLocalVideo
-
bool dataOnly
optional(=false) option to ensure that video and audio stream channels are turned off -
bool enableDataChannels
optional(=true) option to enable/disable data channels (used for volume levels or direct messaging) -
bool autoRemoveVideos
- optional(=true) option to automatically remove video elements when streams are stopped. -
bool adjustPeerVolume
- optional(=true) option to reduce peer volume when the local participant is speaking -
number peerVolumeWhenSpeaking
- optional(=.0.25) value used in conjunction withadjustPeerVolume
. Uses values between 0 and 1. -
object media
- media options to be passed togetUserMedia
. Defaults to{ video: true, audio: true }
. Valid configurations described on MDN with official spec at w3c. -
object receiveMedia
- optional RTCPeerConnection options. Defaults to{ offerToReceiveAudio: 1, offerToReceiveVideo: 1 }
. -
object localVideo
- optional options for attaching the local video stream to the page. Defaults to
{ autoplay: true, // automatically play the video stream on the page mirror: true, // flip the local video to mirror mode (for UX) muted: true // mute local video stream to prevent echo }
-
object logger
- optional alternate logger for the instance; any object that implementslog
,warn
, anderror
methods.
-
Fields
capabilities
- the webrtcsupport module that returns an object that
describes browser capabilities.
config
- the configuration options extended from options passed to the
constructor
connection
- the socket (or alternate) signaling connection
webrtc
- the underlying WebRTC session manager
Events
To set up event listeners, use the LioWebRTC instance created with the constructor. Example:
webrtc.on('connectionReady', (sessionId) => {
// ...
})
'connectionReady', sessionId
- emitted when the signaling connection emits the
connect
event, with the unique id for the session.
'receivedPeerData', type, payload, peer
- emitted when a peer sends data via shout
or whisper
'createdPeer', peer
- emitted three times:
-
when joining a room with existing peers, once for each peer
-
when a new peer joins a joined room
-
when sharing screen, once for each peer
-
peer
- the object representing the peer and underlying peer connection
'stunservers', [...args]
- emitted when the signaling connection emits the
same event
'turnservers', [...args]
- emitted when the signaling connection emits the
same event
'localScreenAdded', el
- emitted after triggering the start of screen sharing
-
el
the element that contains the local screen stream
'leftRoom', roomName
- emitted after successfully leaving the current room,
ending all peers, and stopping the local screen stream
'videoAdded', videoEl, peer
- emitted when a peer stream is added
-
videoEl
- the video element associated with the stream that was added -
peer
- the peer associated with the stream that was added
'videoRemoved', videoEl, peer
- emitted when a peer stream is removed
-
videoEl
- the video element associated with the stream that was removed -
peer
- the peer associated with the stream that was removed
Methods
createRoom(name, callback)
- emits the create
event on the connection with
name
and (if provided) invokes callback
on response
joinRoom(name, callback)
- joins the conference in room name
. Callback is
invoked with callback(err, roomDescription)
where roomDescription
is yielded
by the connection on the join
event. See signalmaster for more details.
startLocalVideo()
- starts the local media with the media
options provided
in the config passed to the constructor
testReadiness()
- tests that the connection is ready and that (if media is
enabled) streams have started
mute()
- mutes the local audio stream for all peers (pauses sending audio)
unmute()
- unmutes local audio stream for all peers (resumes sending audio)
pauseVideo()
- pauses sending video to peers
resumeVideo()
- resumes sending video to all peers
pause()
- pauses sending audio and video to all peers
resume()
- resumes sending audio and video to all peers
sendToAll(messageType, payload)
- broadcasts a message to all peers in the
room via the signaling channel (websocket)
-
string messageLabel
- The event label that be broadcasted via the signaling server -
object payload
- an arbitrary value or object to send to peers
sendDirectlyToAll(messageType, payload, channel)
- broadcasts a message
to all peers in the room via a dataChannel
-
string messageType
- the event label that peers will listen for -
object payload
- an arbitrary value or object to send to peers -
string channel
- (optional) the label for the dataChannel to send on
shout(messageType, payload)
- broadcasts a message
to all peers in the room via the default data channel
-
string messageType
- A value that represents the classification of the payload -
object payload
- an arbitrary value or object to send to peers
whisper(peer, messageType, payload)
- sends a message to a single peer in the room
-
string messageType
- A value that represents the classification of the payload -
object payload
- an arbitrary value or object to send to peers
getPeers(sessionId, type)
- returns all peers by sessionId
and/or type
shareScreen(callback)
- initiates screen capture request to browser, then
adds the stream to the conference
getLocalScreen()
- returns the local screen stream
stopScreenShare()
- stops the screen share stream and removes it from the room
stopLocalVideo()
- stops all local media streams
setVolumeForAll(volume)
- used to set the volume level for all peers
-
volume
- the volume level, between 0 and 1
leaveRoom()
- leaves the currently joined room and stops local screen share
disconnect()
- calls disconnect
on the signaling connection and deletes it
handlePeerStreamAdded(peer)
- used internally to attach media stream to the
DOM and perform other setup
handlePeerStreamRemoved(peer)
- used internally to remove the video container
from the DOM and emit videoRemoved
getDomId(peer)
- used internally to get the DOM id associated with a peer
getEl(idOrEl)
- helper used internally to get an element where idOrEl
is
either an element, or an id of an element
getLocalVideoContainer()
- used internally to get the container that will hold
the local video element
getRemoteVideoContainer()
- used internally to get the container that holds
the remote video elements
Signaling
Connection
For signaling, LioWebRTC uses socket.io to communicate with the signaling server. The connection object comes with these methods:
-
on(ev, fn)
- A method to invokefn
when eventev
is triggered -
emit()
- A method to send/emit arbitrary arguments on the connection -
getSessionId()
- A method to get a unique session Id for the connection -
disconnect()
- A method to disconnect the connection
Signaling Server
LioWebRTC uses the signaling server provided for testing purposes by SimpleWebRTC. You will need to set up your own signalmaster server, and pass in your server's url when creating a new instance of LioWebRTC.