common.js

var browserFakeUserAgent = 'Fake/5.0 (FakeOS) AppleWebKit/123 (KHTML, like Gecko) Fake/12.3.4567.89 Fake/123.45';

var isNodejs = typeof process === 'object' && typeof process.versions === 'object' && process.versions.node && /*node-process*/ !process.browser;
if (isNodejs) {
    var version = process.versions.node.toString().replace('v', '');
    browserFakeUserAgent = 'Nodejs/' + version + ' (NodeOS) AppleWebKit/' + version + ' (KHTML, like Gecko) Nodejs/' + version + ' Nodejs/' + version
}

(function(that) {
    if (typeof window !== 'undefined') {
        return;
    }

    if (typeof window === 'undefined' && typeof global !== 'undefined') {
        global.navigator = {
            userAgent: browserFakeUserAgent,
            getUserMedia: function() {}
        };

        /*global window:true */
        that.window = global;
    } else if (typeof window === 'undefined') {
        // window = this;
    }

    if (typeof location === 'undefined') {
        /*global location:true */
        that.location = {
            protocol: 'file:',
            href: '',
            hash: ''
        };
    }

    if (typeof screen === 'undefined') {
        /*global screen:true */
        that.screen = {
            width: 0,
            height: 0
        };
    }
})(typeof global !== 'undefined' ? global : window);

/*global navigator:true */
var navigator = window.navigator;

if (typeof navigator !== 'undefined') {
    if (typeof navigator.webkitGetUserMedia !== 'undefined') {
        navigator.getUserMedia = navigator.webkitGetUserMedia;
    }

    if (typeof navigator.mozGetUserMedia !== 'undefined') {
        navigator.getUserMedia = navigator.mozGetUserMedia;
    }
} else {
    navigator = {
        getUserMedia: function() {},
        userAgent: browserFakeUserAgent
    };
}