This is a high level helper module designed to help you get up an running with WebRTC really, really quickly. By using this module you are trading off some flexibility, so if you need a more flexible configuration you should drill down into lower level components of the rtc.io suite. In particular you should check out rtc.
In the simplest case you simply call quickconnect with a single string argument which tells quickconnect which server to use for signaling:
var quickconnect = require('rtc-quickconnect');
quickconnect('https://switchboard.rtc.io/', { room: 'qc-simple-demo' })
.on('call:started', function(id, pc, data) {
console.log('we have a new connection to: ' + id);
});
The first argument to quickconnect is the URL of the signalling server, the second is a set of options given as a JSON object. Valid options are described below.
The following events are emitted from the signalling object created by calling quickconnect()
. Additionally, any of the underlying signaller events can also be used.
The peer level events provided in quickconnect provide you the ability to tap into the various stages of the lifecycle for connecting with a peer, before the connection actually migrates to the status of a connected "call".
-
peer:connect => function(id, peerconnection, data)
The
peer:connect
event is emitted when we first create a connection to a discovered peer. Thepeerconnection
argument is a standardRTCPeerConnection
instance. -
peer:couple => funtion(id, peerconnection, data, monitor)
The
peer:couple
event is emitted when once quickconnect has coupled to its remote counterpart.
A "call" in quickconnect is equivalent to an established RTCPeerConnection
between this quickconnect instance a remote peer.
-
call:started => function(id, peerconnection, data)
Triggered once a peer connection has been established been established between this quickconnect instance and another.
-
call:ended => function(id)
Triggered when a peer connection has been closed. This may be due to the peer connection itself indicating that it has been closed, or we may have lost connection with the remote signaller and the connection has timed out.
-
call:expired => function(id)
Triggered when a peer connection is timed out due to the expiry of the heartbeat to the remote peer. Note that this event is thrown before (and in addition to) the more generic
call:ended
event.
-
channel:opened => function(id, datachannel, data)
The
channel:opened
event is triggered whenever anRTCDataChannel
has been opened (it's ready to send data) to a remote peer. -
channel:opened:%label% => function(id, datachannel, data)
This is equivalent of the
channel:opened
event, but only triggered for a channel with label%label%
. For example:quickconnect('https://switchboard.rtc.io/', { room: 'test' }) .createDataChannel('foo') .createDataChannel('bar') .on('channel:opened:foo', function(id, dc) { console.log('channel foo opened for peer: ' + id); });
In the case above the console message would only be displayed for the
foo
channel once open, and when thebar
channel is opened no handler would be invoked. -
channel:closed => function(id, datachannel, label)
Emitted when the channel has been closed, works when a connection has been closed or the channel itself has been closed.
-
channel:closed:%label% => function(id, datachannel, label)
The label specific equivalent of
channel:closed
.
-
stream:added => function(id, stream, data)
The
stream:added
event is triggered when anRTCPeerConnection
has successfully been established to another peer that contains remote streams. Additionally, if you are using quickconnect in its "reactive" mode then you will also receivestream:added
events as streams are dynamically added to the connection by the remote peer. -
stream:removed => function(id)
As per the
stream:added
event but triggered when a stream has been removed.
When working with WebRTC data channels, you can call the createDataChannel
function helper that is attached to the object returned from the quickconnect
call. The createDataChannel
function signature matches the signature of the RTCPeerConnection
createDataChannel
function.
At the minimum it requires a label for the channel, but you can also pass through a dictionary of options that can be used to fine tune the data channel behaviour. For more information on these options, I'd recommend having a quick look at the WebRTC spec:
http://dev.w3.org/2011/webrtc/editor/webrtc.html#dictionary-rtcdatachannelinit-members
If in doubt, I'd recommend not passing through options.
var freeice = require('freeice');
var quickconnect = require('rtc-quickconnect');
var opts = {
room: 'qcexample-dctest',
// debug: true,
iceServers: freeice()
};
quickconnect('https://switchboard.rtc.io/', opts)
// tell quickconnect we want a datachannel called test
.createDataChannel('test')
// when the test channel is open, let us know
.on('channel:opened:test', function(id, dc) {
dc.onmessage = function(evt) {
console.log('peer ' + id + ' says: ' + evt.data);
};
console.log('test dc open for peer: ' + id);
dc.send('hi');
});
Another example is displayed below, and this example demonstrates how to use rtc-quickconnect
to create a simple video conferencing application:
var quickconnect = require('rtc-quickconnect');
var crel = require('crel');
var capture = require('rtc-capture');
var attach = require('rtc-attach');
var qsa = require('fdom/qsa');
var plugins = [
require('rtc-plugin-temasys')
];
// create containers for our local and remote video
var local = crel('div', { class: 'local' });
var remote = crel('div', { class: 'remote' });
var peerMedia = {};
// once media is captured, connect
capture({ audio: true, video: true }, { plugins: plugins }, function(err, localStream) {
if (err) {
return console.error('could not capture media: ', err);
}
// render the local media
attach(localStream, { plugins: plugins }, function(err, el) {
local.appendChild(el);
});
// initiate connection
quickconnect('https://switchboard.rtc.io/', { room: 'conftest', plugins: plugins })
// broadcast our captured media to other participants in the room
.addStream(localStream)
// when a peer is connected (and active) pass it to us for use
.on('call:started', function(id, pc, data) {
attach(pc.getRemoteStreams()[0], { plugins: plugins }, function(err, el) {
if (err) return;
el.dataset.peer = id;
remote.appendChild(el);
});
})
// when a peer leaves, remove teh media
.on('call:ended', function(id) {
qsa('*[data-peer="' + id + '"]', remote).forEach(function(el) {
el.parentNode.removeChild(el);
});
});
});
/* extra code to handle dynamic html and css creation */
// add some basic styling
document.head.appendChild(crel('style', [
'.local { position: absolute; right: 10px; }',
'.local video { max-width: 200px; }'
].join('\n')));
// add the local and remote elements
document.body.appendChild(local);
document.body.appendChild(remote);
Signaling is an important part of setting up a WebRTC connection and for our examples we use our own test instance of the rtc-switchboard. For your testing and development you are more than welcome to use this also, but just be aware that we use this for our testing so it may go up and down a little. If you need something more stable, why not consider deploying an instance of the switchboard yourself - it's pretty easy :)
quickconnect(signalhost, opts?) => rtc-sigaller instance (+ helpers)
The options provided to the rtc-quickconnect
module function influence the
behaviour of some of the underlying components used from the rtc.io suite.
Listed below are some of the commonly used options:
-
ns
(default: '')An optional namespace for your signalling room. While quickconnect will generate a unique hash for the room, this can be made to be more unique by providing a namespace. Using a namespace means two demos that have generated the same hash but use a different namespace will be in different rooms.
-
room
(default: null) added 0.6Rather than use the internal hash generation (plus optional namespace) for room name generation, simply use this room name instead. NOTE: Use of the
room
option takes precendence overns
. -
debug
(default: false) -
plugins
(default: '')An optional array of rtc-plugins to add, e.g. add Temasys plugin as list item
plugins = [ require('rtc-plugin-temasys')];
Write rtc.io suite debug output to the browser console.
-
expectedLocalStreams
(default: not specified) added 3.0By providing a positive integer value for this option will mean that the created quickconnect instance will wait until the specified number of streams have been added to the quickconnect "template" before announcing to the signaling server.
-
manualJoin
(default:false
)Set this value to
true
if you would prefer to call thejoin
function to connecting to the signalling server, rather than having that happen automatically as soon as quickconnect is ready to.
Options that are passed onto the rtc.createConnection function:
-
iceServers
This provides a list of ice servers that can be used to help negotiate a connection between peers.
-
constraints
(default: '')An optional RTCConstraints object that is handed to the RTCPeerConnection call, e.g.
constraints: {"optional": [ {'googIPv6': 'false'} ] }
orconstraints: {"optional": [ {RtpDataChannels: true} ] }
-
sdpfilter
(default '')An optional function to provide for sdp munging, e.g.
sdpfilter: function(sdp) { console.log('filtering sdp'); return limitBandwidthSDP(sdp);}
Under the hood, quickconnect uses the rtc/couple logic, and the options passed to quickconnect are also passed onto this function.
The following are functions that are patched into the rtc-signaller
instance that make working with and creating functional WebRTC applications
a lot simpler.
addStream(stream:MediaStream) => qc
Add the stream to active calls and also save the stream so that it can be added to future calls.
The addTrack
function terminates do the pure WebRTC addTrack logic.
The replaceTrack
function call web WebRTC API for replaceTrack (sender)
replaceTrack(newTrack, oldTrackId)
The endCall
function terminates the active call with the given ID.
If a call with the call ID does not exist it will do nothing.
The endCalls
function terminates all the active calls that have been
created in this quickconnect instance. Calling endCalls
does not
kill the connection with the signalling server.
The close
function provides a convenient way of closing all associated
peer connections. This function simply uses the endCalls
function and
the underlying leave
function of the signaller to do a "full cleanup"
of all connections.
Request that a data channel with the specified label
is created on
the peer connection. When the data channel is open and available, an
event will be triggered using the label of the data channel.
For example, if a new data channel was requested using the following call:
var qc = quickconnect('https://switchboard.rtc.io/').createDataChannel('test');
Then when the data channel is ready for use, a test:open
event would
be emitted by qc
.
The join
function is used when manualJoin
is set to true when creating
a quickconnect instance. Call the join
function once you are ready to
join the signalling server and initiate connections with other people.
The get
function returns the property value for the specified property name.
Return a copy of the local streams that have currently been configured
Flag that this session will be a reactive connection.
removeStream(stream:MediaStream)
Remove the specified stream from both the local streams that are to be connected to new peers, and also from any active calls.
requestChannel(targetId, label, callback)
This is a function that can be used to respond to remote peers supplying
a data channel as part of their configuration. As per the receiveStream
function this function will either fire the callback immediately if the
channel is already available, or once the channel has been discovered on
the call.
requestStream(targetId, idx, callback)
Used to request a remote stream from a quickconnect instance. If the
stream is already available in the calls remote streams, then the callback
will be triggered immediately, otherwise this function will monitor
stream:added
events and wait for a match.
In the case that an unknown target is requested, then an exception will be thrown.
Update the profile data with the attached information, so when the signaller announces it includes this data in addition to any room and id information.
waitForCall(targetId, callback)
Wait for a call from the specified targetId. If the call is already
active the callback will be fired immediately, otherwise we will wait
for a call:started
event that matches the requested targetId
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.