rtc-signal

Core rtc.io signal processing logic available for use in rtc.io signallers.

Reference

prepare

fn(args) => String

Convert an array of values into a pipe-delimited string.

process

fn(signaller, opts) => fn(message)

The core processing logic that is used to respond to incoming signaling messages.

signaller(opts, bufferMessage) => mbus

Create a base level signaller which is capable of processing messages from an incoming source. The signaller is capable of sending messages outbound using the bufferMessage function that is supplied to the signaller.

isMaster(targetId) => Boolean

A simple function that indicates whether the local signaller is the master for it's relationship with peer signaller indicated by targetId. Roles are determined at the point at which signalling peers discover each other, and are simply worked out by whichever peer has the lowest signaller id when lexigraphically sorted.

For example, if we have two signaller peers that have discovered each others with the following ids:

• b11f4fd0-feb5-447c-80c8-c51d8c3cced2
• 8a07f82e-49a5-4b9b-a02e-43d911382be6

They would be assigned roles:

• b11f4fd0-feb5-447c-80c8-c51d8c3cced2
• 8a07f82e-49a5-4b9b-a02e-43d911382be6 (master)

send(args*)

Prepare a message for sending, e.g.:

signaller.send('/foo', 'bar');

to(targetId)

Use the to function to send a message to the specified target peer. A large parge of negotiating a WebRTC peer connection involves direct communication between two parties which must be done by the signalling server. The to function provides a simple way to provide a logical communication channel between the two parties:

var send = signaller.to('e95fa05b-9062-45c6-bfa2-5055bf6625f4').send;

// create an offer on a local peer connection
pc.createOffer(
  function(desc) {
    // set the local description using the offer sdp
    // if this occurs successfully send this to our peer
    pc.setLocalDescription(
      desc,
      function() {
        send('/sdp', desc);
      },
      handleFail
    );
  },
  handleFail
);

Signaller Internals

The following functions are designed for use by signallers that are built on top of this base signaller.

_announce()

The internal function that constructs the /announce message and triggers the local:announce event.

_process(data)

_update

Internal function that updates core announce attributes with updated data.

License(s)

Apache 2.0

Copyright 2013 - 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.