communication

CommunicationJS

Utilize WebRTC PeerConnection API

Hide session establishing process, handle stream persistency

Usage

 
import Communication from 'communication'
import webrtc from 'communication-adaptor-webrtc'
 
if (!webrtc.support) {
  throw new Error('This browser does not support WebRTC API')
}
 
let comm = Communication(webrtc)
 
comm.on('message', msg => {
  mySignalChannel.send(msg)
})
 
mySignalChannel.on('message', msg => {
  comm.write(msg)
})
 
comm.open()
 
let streamId = null
 
comm.on('streamAdded', (stream, id, meta) => {
  if (streamId != null) return
  streamId = id
  myDescription.textContent = meta.description
  myMedia.src = URL.createObjectURL(stream)
})
 
comm.on('streamUpdated', (stream, id) => {
  if (id !== streamId) return
  myMedia.src = URL.createObjectURL(stream)
})
 
comm.on('streamRemoved', id => {
  if (id !== streamID) return
  streamId = null
  myMedia.src = null
})
 
let localStream = getStreamSomehow()
 
comm.addStream(localStream, {
  description: 'my nice stream'
})
 

Method

state(): String

Get current Communication state

will return one of following values

• 'waiting': Communication is not established
• 'running': Communication is established and usable
• 'closed': Communication is closed

open(): Communication

Start establishing connection

This method MUST be called AFTER message handling, BEFORE any other operation

write(message: String): Communication

Receive message from signalling channel

addStream(stream: MediaStream, meta: Object): Communication

Add local MediaStream to the Communication

Metadata object will be sent to the remote Communication object

See streamAdded event

removeStream(stream: MediaStream|String): Communication

Remove local MediaStream from the Communication

getLocalStreams(): Array

Return an array of MediaStreams that Communication streaming to remote peer

getRemoteStreams(): Array

Return an array of MediaStreams that Communication streaming from remote peer

getStreamById(id: String): MediaStream

Return an MediaStream from given id

Note: if stream is sent from remote peer, stream.id may not be same as given id

close(): void

Close this communication permanently

Event

message(msg: String)

Communication has a new message to send to remote peer

running()

Connection to remote peer is established

This Communication is now workable

streamAdded(stream: MediaStream, id: String, meta: Object)

Remote peer added another stream to Communication

See addStream method

streamUpdated(stream: MediaStream, id: String)

Existing stream is re-established for some reason(ex) internet connection is unstable)

For stream sender, newly arrived stream is just same stream as previous stream with same id

Just replace previous stream with this one is enough to handle stream persistency

streamRemoved(id: String)

Remote peer removed stream from Communication

closed(fromRemote: Boolean, reason: Any)

This Communication is closed permanently