rtc-tools

The rtc-tools module does most of the heavy lifting within the
rtc.io suite. Primarily it handles the logic of coupling
a local RTCPeerConnection with it's remote counterpart via an
rtc-signaller signalling
channel.


  

Getting Started

If you decide that the rtc-tools module is a better fit for you than either
rtc-quickconnect or
rtc then the code snippet below
will provide you a guide on how to get started using it in conjunction with
the rtc-signaller (version 5.0 and above)
and rtc-media modules:

``js
var messenger = require('rtc-switchboard-messenger');
var signaller = require('rtc-signaller')(messenger('https://switchboard.rtc.io/'));
var rtc = require('rtc-tools');
var getUserMedia = require('getusermedia');
var attachMedia = require('attachmediastream');

// capture local media first as firefox
// will want a local stream and doesn't support onnegotiationneeded event
getUserMedia({ video: true, audio: true }, function(err, localStream) {
if (err) {
return console.error('could not capture media: ', err);
}

document.body.appendChild(attachMedia(localStream));

// look for friends
signaller.on('peer:announce', function(data) {
var pc = rtc.createConnection();
var monitor = rtc.couple(pc, data.id, signaller);

// add the stream to the connection
pc.addStream(localStream);

// once the connection is active, log a console message
monitor.once('connected', function() {
console.log('connection active to: ' + data.id);

pc.getRemoteStreams().forEach(function(stream) {
document.body.appendChild(attachMedia(stream));
});
});


monitor.createOffer();
});

// announce ourself in the rtc-getting-started room
signaller.announce({ room: 'rtc-getting-started' });
});

`

This code definitely doesn't cover all the cases that you need to consider
(i.e. peers leaving, etc) but it should demonstrate how to:

1. Capture video and add it to a peer connection
2. Couple a local peer connection with a remote peer connection
3. Deal with the remote steam being discovered and how to render
that to the local interface.

Reference

$3

`
createConnection(opts?, constraints?) => RTCPeerConnection
`

Create a new RTCPeerConnection auto generating default opts as required.

`js
var conn;

// this is ok
conn = rtc.createConnection();

// and so is this
conn = rtc.createConnection({
iceServers: []
});
`

$3

`
cleanup(pc)
`

The cleanup function is used to ensure that a peer connection is properly
closed and ready to be cleaned up by the browser.

$3

#### couple(pc, targetId, signaller, opts?)

Couple a WebRTC connection with another webrtc connection identified by
targetId via the signaller.

The following options can be provided in the opts argument:

- sdpfilter (default: null)

A simple function for filtering SDP as part of the peer
connection handshake (see the Using Filters details below).

##### Example Usage

`js
var couple = require('rtc/couple');

couple(pc, '54879965-ce43-426e-a8ef-09ac1e39a16d', signaller);
`

##### Using Filters

In certain instances you may wish to modify the raw SDP that is provided
by the createOffer and createAnswer calls. This can be done by passing
a sdpfilter function (or array) in the options. For example:

`js
// run the sdp from through a local tweakSdp function.
couple(pc, '54879965-ce43-426e-a8ef-09ac1e39a16d', signaller, {
sdpfilter: tweakSdp
});
`

$3

Provide the rtc-core/detect
functionality.

$3

The generators package provides some utility methods for generating
constraint objects and similar constructs.

`js
var generators = require('rtc/generators');
`

#### generators.config(config)

Generate a configuration object suitable for passing into an W3C
RTCPeerConnection constructor first argument, based on our custom config.

In the event that you use short term authentication for TURN, and you want
to generate new iceServers regularly, you can specify an iceServerGenerator
that will be used prior to coupling. This generator should return a fully
compliant W3C (RTCIceServer dictionary)[http://www.w3.org/TR/webrtc/#idl-def-RTCIceServer].

If you pass in both a generator and iceServers, the iceServers _will be
ignored and the generator used instead.

#### generators.connectionConstraints(flags, constraints)

This is a helper function that will generate appropriate connection
constraints for a new RTCPeerConnection object which is constructed
in the following way:

`js
var conn = new RTCPeerConnection(flags, constraints);
`

In most cases the constraints object can be left empty, but when creating
data channels some additional options are required. This function
can generate those additional options and intelligently combine any
user defined constraints (in constraints) with shorthand flags that
might be passed while using the rtc.createConnection helper.

$3

`
monitor(pc, targetId, signaller, parentBus) => mbus
`

The monitor is a useful tool for determining the state of pc (an
RTCPeerConnection) instance in the context of your application. The
monitor uses both the iceConnectionState information of the peer
connection and also the various
signaller events
to determine when the connection has been connected and when it has
been disconnected.

A monitor created mbus` is returned as the result of a
couple between a local peer
connection and it's remote counterpart.

License(s)

$3

Copyright 2015 National ICT Australia Limited (NICTA)

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.