Developing WebRTC web applications for OpenWebRTC and Bowser

OpenWebRTC supports the latest WebRTC JavaScript API and web apps that run in OpenWebRTC / Bowser will most likely also work in other WebRTC enabled browsers, such as Chrome and Firefox.

The WebRTC API is not yet finalised and part of the reason for OpenWebRTC's existence is to be an interoperable implementation. As with any other web API, small differences in how the APIs work in the respective browsers can exist.

This page hopes to document them to make your life easier when writing web code to work with other popular browsers and OpenWebRTC (in the form of Bowser, the openwebrtc-daemon or, for example, an iOS hybrid app.)

Bowser-specific Notes

For Bowser-specific notes, see here

WebRTC API and prefixes

Where needed the webkit prefix is used for WebRTC API's. Examples of top level WebRTC API's:

navigator.webkitGetUserMedia = getUserMedia;
webkitMediaStream = MediaStream;
webkitRTCPeerConnection = RTCPeerConnection;
RTCSessionDescription
RTCIceCandidate

All API's are defined in webrtc.js if you want to check the source.

General Notes

• WebRTC classes may not exist until after the page load has finished - This is because the page needs to download and execute owr.js. You need to be aware of this if you check for webrtc support on page load.
• Video DOM elements will be swapped out
  • Don't cache the DOM elements in JavaScript
  • Be aware that certain attributes (like angular ng-*) will be lost from video elements. Put them on a container <div>.

Selecting camera

On devices where multiple cameras are available, such as mobile devices, you can select which camera that should be used ("user" or "environment"):

var mode = "user"; // or "environment"
var options = { "audio": true, "video": { "facingMode": mode } };
navigator.webkitGetUserMedia(options, function (stream) {
   ...
});

Reference application

If you get stuck we also provide a reference WebRTC application that works in Bowser/OpenWebRTC, Chrome and Firefox.

Debugging

The preferred method for debugging WebRTC web applications quickly is to run the web application in Firefox or OS X Safari, along with the OpenWebRTC daemon and browser extension. This is particularly useful to debug issues related to call setup and signalling.