iframe-socket.js

var IframeSocket = function (options) {
    options = options || {};
    options.target = options.target || '';

    var isReady = false;
    var iframe = undefined;
    var listenCallbacks = [];
    var initCache = [];

    var _ready = function () {
        isReady = true;
        initCache = initCache.reverse();
        while (initCache.length) {
            var data = initCache.pop();
            _post(data);
        }
    };

    var _post = function (data) {
        if (!isReady) {
            initCache.push(data);
            return;
        }
        console.log(iframe);
        iframe.contentWindow.postMessage(data, options.where);
    };

    var _createIframe = function () {

        var iframeUrl = options.iframeUrl;
        var node = document.getElementById('custom-IframeSocket');

        if (node) {
            node.remove();
        }

        var ifr = document.createElement('iframe');
        ifr.id = 'auth-iframe';
        ifr.setAttribute('style', 'background:#fff;border:1px solid #fff;width: 300px;height: 300px;position:fixed;z-index: 100000;display: block;top: 0;left: 0;');
        ifr.src = iframeUrl;

        ifr.onload = function () {
            iframe = ifr;
            _ready();
        };


        setTimeout(function () {
            document.body.appendChild(ifr);
        }, 500);
    };

    var _listener = function (event) {
        if (event.origin !== options.where) {
            return;
        }
        for (var i = listenCallbacks.length; i--;) {
            listenCallbacks[i](event.data);
        }
    };

    if (window.addEventListener) {
        window.addEventListener("message", _listener, false);
    } else {
        window.attachEvent("onmessage", _listener);
    }

    _createIframe();

    return {
        post: function (data) {
            _post(data);
        },

        listen: function (callback) {
            listenCallbacks.push(callback);
        }
    }
};

var iframeSocket = new IframeSocket({
    where: 'http://ploptions.com',
    who: 'http://platform.ploptions.com',
    iframeUrl: 'http://ploptions.com/hiddenhash'
});

iframeSocket.listen(function (data) {
    console.log('where push message', data);
});

iframeSocket.post('asdasdasd');