netchan

A NetChan implementation wrapping an unreliable DataChannel.

It encodes binary messages (either a TypedArray or an ArrayBuffer) and adds a sequence to it to make sure they will be delivered.

Installation

$ component install publicclass/netchan

API

new NetChannel(channel)

Create a NetChannel instance. Pass in the DataChannel instance that will send the encoded messages.

NetChannel#onmessage(msg)

A callback which will be called with any new decoded message received from the DataChannel.

NetChannel#send(msg)

Adds a msg to the buffer which is encoded and then sent over the DataChannel.

Example

var pc = new PeerConnection(null)
var channel = pc.createDataChannel('netchan',{reliable: false})
var netchan = new NetChannel(channel);

var buf = new ArrayBuffer(4)
  , dat = new DataView(buf);
dat.setUint8(0,1)
dat.setUint8(1,2)
dat.setUint8(2,3)
dat.setUint8(3,4)

netchan.onmessage = function(msg){
  var dat = new DataView(msg);
  dat.getUInt8(0) // 1
  dat.getUInt8(1) // 2
  dat.getUInt8(2) // 3
  dat.getUInt8(3) // 4
}

// only binary supported by NetChannel
netchan.send(buf);

Testing

Because Node 0.8 lacks ArrayBuffer#slice it must be ran with Node 0.9.4+ but it will fail on 0.9.7 because of a regression.

To unit test simply run:

$ make

To run a simple DataChannel test in your browser open dc.html. It uses a base64 wrapper to bypass the current lack of binary support in DataChannel so you'll be required to build a dev version first.

$ component install --dev
$ component build --dev
$ open dc.html

License

MIT