Javascript
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1652行
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46.47 KB
// Copyright (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Parts Copyright 2005-2009, the Dojo Foundation. Used under the terms of the
// "New" BSD License:
//
// http://download.dojotoolkit.org/release-1.3.2/dojo-release-1.3.2/dojo/LICENSE
//
/**
* @fileoverview CFInstance.js provides a set of utilities for managing
* ChromeFrame plugins, including creation, RPC services, and a singleton to
* use for communicating from ChromeFrame hosted content to an external
* CFInstance wrapper. CFInstance.js is stand-alone, designed to be served from
* a CDN, and built to not create side-effects for other hosted content.
* @author slightlyoff@google.com (Alex Russell)
*/
(function(scope) {
// TODO:
// * figure out if there's any way to install w/o a browser restart, and if
// so, where and how
// * slim down Deferred and RPC scripts
// * determine what debugging APIs should be exposed and how they should be
// surfaced. What about content authoring in Chrome instances? Stubbing
// the other side of RPC's?
// bail if we'd be over-writing an existing CFInstance object
if (scope['CFInstance']) {
return;
}
/////////////////////////////////////////////////////////////////////////////
// Utiliity and Cross-Browser Functions
/////////////////////////////////////////////////////////////////////////////
// a monotonically incrementing counter
var _counter = 0;
var undefStr = 'undefined';
//
// Browser detection: ua.isIE, ua.isSafari, ua.isOpera, etc.
//
/**
* An object for User Agent detection
* @type {!Object}
* @protected
*/
var ua = {};
var n = navigator;
var dua = String(n.userAgent);
var dav = String(n.appVersion);
var tv = parseFloat(dav);
var duaParse = function(s){
var c = 0;
try {
return parseFloat(
dua.split(s)[1].replace(/\./g, function() {
c++;
return (c > 1) ? '' : '.';
} )
);
} catch(e) {
// squelch to intentionally return undefined
}
};
/** @type {number} */
ua.isOpera = dua.indexOf('Opera') >= 0 ? tv: undefined;
/** @type {number} */
ua.isWebKit = duaParse('WebKit/');
/** @type {number} */
ua.isChrome = duaParse('Chrome/');
/** @type {number} */
ua.isKhtml = dav.indexOf('KHTML') >= 0 ? tv : undefined;
var index = Math.max(dav.indexOf('WebKit'), dav.indexOf('Safari'), 0);
if (index && !ua.isChrome) {
/** @type {number} */
ua.isSafari = parseFloat(dav.split('Version/')[1]);
if(!ua.isSafari || parseFloat(dav.substr(index + 7)) <= 419.3){
ua.isSafari = 2;
}
}
if (dua.indexOf('Gecko') >= 0 && !ua.isKhtml) {
/** @type {number} */
ua.isGecko = duaParse(' rv:');
}
if (ua.isGecko) {
/** @type {number} */
ua.isFF = parseFloat(dua.split('Firefox/')[1]) || undefined;
}
if (document.all && !ua.isOpera) {
/** @type {number} */
ua.isIE = parseFloat(dav.split('MSIE ')[1]) || undefined;
}
/**
* Log out varargs to a browser-provided console object (if available). Else
* a no-op.
* @param {*} var_args Optional Things to log.
* @protected
**/
var log = function() {
if (window['console']) {
try {
if (ua.isSafari || ua.isChrome) {
throw Error();
}
console.log.apply(console, arguments);
} catch(e) {
try {
console.log(toArray(arguments).join(' '));
} catch(e2) {
// squelch
}
}
}
};
//
// Language utility methods
//
/**
* Determine if the passed item is a String
* @param {*} item Item to test.
* @protected
**/
var isString = function(item) {
return typeof item == 'string';
};
/**
* Determine if the passed item is a Function object
* @param {*} item Item to test.
* @protected
**/
var isFunction = function(item) {
return (
item && (
typeof item == 'function' || item instanceof Function
)
);
};
/**
* Determine if the passed item is an array.
* @param {*} item Item to test.
* @protected
**/
var isArray = function(item){
return (
item && (
item instanceof Array || (
typeof item == 'object' &&
typeof item.length != undefStr
)
)
);
};
/**
* A toArray version which takes advantage of builtins
* @param {*} obj The array-like object to convert to a real array.
* @param {number} opt_offset An index to being copying from in the source.
* @param {Array} opt_startWith An array to extend with elements of obj in
* lieu of creating a new array to return.
* @private
**/
var _efficientToArray = function(obj, opt_offset, opt_startWith){
return (opt_startWith || []).concat(
Array.prototype.slice.call(obj, opt_offset || 0 )
);
};
/**
* A version of toArray that iterates in lieu of using array generics.
* @param {*} obj The array-like object to convert to a real array.
* @param {number} opt_offset An index to being copying from in the source.
* @param {Array} opt_startWith An array to extend with elements of obj in
* @private
**/
var _slowToArray = function(obj, opt_offset, opt_startWith){
var arr = opt_startWith || [];
for(var x = opt_offset || 0; x < obj.length; x++){
arr.push(obj[x]);
}
return arr;
};
/**
* Converts an array-like object (e.g., an "arguments" object) to a real
* Array.
* @param {*} obj The array-like object to convert to a real array.
* @param {number} opt_offset An index to being copying from in the source.
* @param {Array} opt_startWith An array to extend with elements of obj in
* @protected
*/
var toArray = ua.isIE ?
function(obj){
return (
obj.item ? _slowToArray : _efficientToArray
).apply(this, arguments);
} :
_efficientToArray;
var _getParts = function(arr, obj, cb){
return [
isString(arr) ? arr.split('') : arr,
obj || window,
isString(cb) ? new Function('item', 'index', 'array', cb) : cb
];
};
/**
* like JS1.6 Array.forEach()
* @param {Array} arr the array to iterate
* @param {function(Object, number, Array)} callback the method to invoke for
* each item in the array
* @param {function?} thisObject Optional a scope to use with callback
* @return {array} the original arr
* @protected
*/
var forEach = function(arr, callback, thisObject) {
if(!arr || !arr.length){
return arr;
}
var parts = _getParts(arr, thisObject, callback);
// parts has a structure of:
// [
// array,
// scope,
// function
// ]
arr = parts[0];
for (var i = 0, l = arr.length; i < l; ++i) {
parts[2].call( parts[1], arr[i], i, arr );
}
return arr;
};
/**
* returns a new function bound to scope with a variable number of positional
* params pre-filled
* @private
*/
var _hitchArgs = function(scope, method /*,...*/) {
var pre = toArray(arguments, 2);
var named = isString(method);
return function() {
var args = toArray(arguments);
var f = named ? (scope || window)[method] : method;
return f && f.apply(scope || this, pre.concat(args));
}
};
/**
* Like goog.bind(). Hitches the method (named or provided as a function
* object) to scope, optionally partially applying positional arguments.
* @param {Object} scope the object to hitch the method to
* @param {string|function} method the method to be bound
* @return {function} The bound method
* @protected
*/
var hitch = function(scope, method){
if (arguments.length > 2) {
return _hitchArgs.apply(window, arguments); // Function
}
if (!method) {
method = scope;
scope = null;
}
if (isString(method)) {
scope = scope || window;
if (!scope[method]) {
throw(
['scope["', method, '"] is null (scope="', scope, '")'].join('')
);
}
return function() {
return scope[method].apply(scope, arguments || []);
};
}
return !scope ?
method :
function() {
return method.apply(scope, arguments || []);
};
};
/**
* A version of addEventListener that works on IE too. *sigh*.
* @param {!Object} obj The object to attach to
* @param {!String} type Name of the event to attach to
* @param {!Function} handler The function to connect
* @protected
*/
var listen = function(obj, type, handler) {
if (obj['attachEvent']) {
obj.attachEvent('on' + type, handler);
} else {
obj.addEventListener(type, handler, false);
}
};
/**
* Adds "listen" and "_dispatch" methods to the passed object, taking
* advantage of native event hanlding if it's available.
* @param {Object} instance The object to install the event system on
* @protected
*/
var installEvtSys = function(instance) {
var eventsMap = {};
var isNative = (
(typeof instance.addEventListener != undefStr) &&
((instance['tagName'] || '').toLowerCase() != 'iframe')
);
instance.listen = function(type, func) {
var t = eventsMap[type];
if (!t) {
t = eventsMap[type] = [];
if (isNative) {
listen(instance, type, hitch(instance, "_dispatch", type));
}
}
t.push(func);
return t;
};
instance._dispatch = function(type, evt) {
var stopped = false;
var stopper = function() {
stopped = true;
};
forEach(eventsMap[type], function(f) {
if (!stopped) {
f(evt, stopper);
}
});
};
return instance;
};
/**
* Deserialize the passed JSON string
* @param {!String} json A string to be deserialized
* @return {Object}
* @protected
*/
var fromJson = window['JSON'] ? function(json) {
return JSON.parse(json);
} :
function(json) {
return eval('(' + (json || undefStr) + ')');
};
/**
* String escaping for use in JSON serialization
* @param {string} str The string to escape
* @return {string}
* @private
*/
var _escapeString = function(str) {
return ('"' + str.replace(/(["\\])/g, '\\$1') + '"').
replace(/[\f]/g, '\\f').
replace(/[\b]/g, '\\b').
replace(/[\n]/g, '\\n').
replace(/[\t]/g, '\\t').
replace(/[\r]/g, '\\r').
replace(/[\x0B]/g, '\\u000b'); // '\v' is not supported in JScript;
};
/**
* JSON serialization for arbitrary objects. Circular references or strong
* typing information are not handled.
* @param {Object} it Any valid JavaScript object or type
* @return {string} the serialized representation of the passed object
* @protected
*/
var toJson = window['JSON'] ? function(it) {
return JSON.stringify(it);
} :
function(it) {
if (it === undefined) {
return undefStr;
}
var objtype = typeof it;
if (objtype == 'number' || objtype == 'boolean') {
return it + '';
}
if (it === null) {
return 'null';
}
if (isString(it)) {
return _escapeString(it);
}
// recurse
var recurse = arguments.callee;
if(it.nodeType && it.cloneNode){ // isNode
// we can't seriailize DOM nodes as regular objects because they have
// cycles DOM nodes could be serialized with something like outerHTML,
// but that can be provided by users in the form of .json or .__json__
// function.
throw new Error('Cannot serialize DOM nodes');
}
// array
if (isArray(it)) {
var res = [];
forEach(it, function(obj) {
var val = recurse(obj);
if (typeof val != 'string') {
val = undefStr;
}
res.push(val);
});
return '[' + res.join(',') + ']';
}
if (objtype == 'function') {
return null;
}
// generic object code path
var output = [];
for (var key in it) {
var keyStr, val;
if (typeof key == 'number') {
keyStr = '"' + key + '"';
} else if(typeof key == 'string') {
keyStr = _escapeString(key);
} else {
// skip non-string or number keys
continue;
}
val = recurse(it[key]);
if (typeof val != 'string') {
// skip non-serializable values
continue;
}
// TODO(slightlyoff): use += on Moz since it's faster there
output.push(keyStr + ':' + val);
}
return '{' + output.join(',') + '}'; // String
};
// code to register with the earliest safe onload-style handler
var _loadedListenerList = [];
var _loadedFired = false;
/**
* a default handler for document onload. When called (the first time),
* iterates over the list of registered listeners, calling them in turn.
* @private
*/
var documentLoaded = function() {
if (!_loadedFired) {
_loadedFired = true;
forEach(_loadedListenerList, 'item();');
}
};
if (document.addEventListener) {
// NOTE:
// due to a threading issue in Firefox 2.0, we can't enable
// DOMContentLoaded on that platform. For more information, see:
// http://trac.dojotoolkit.org/ticket/1704
if (ua.isWebKit > 525 || ua.isOpera || ua.isFF >= 3) {
listen(document, 'DOMContentLoaded', documentLoaded);
}
// mainly for Opera 8.5, won't be fired if DOMContentLoaded fired already.
// also used for FF < 3.0 due to nasty DOM race condition
listen(window, 'load', documentLoaded);
} else {
// crazy hack for IE that relies on the "deferred" behavior of script
// tags
document.write(
'<scr' + 'ipt defer src="//:" '
+ 'onreadystatechange="if(this.readyState==\'complete\')'
+ '{ CFInstance._documentLoaded();}">'
+ '</scr' + 'ipt>'
);
}
// TODO(slightlyoff): known KHTML init issues are ignored for now
//
// DOM utility methods
//
/**
* returns an item based on DOM ID. Optionally a doucment may be provided to
* specify the scope to search in. If a node is passed, it's returned as-is.
* @param {string|Node} id The ID of the node to be located or a node
* @param {Node} doc Optional A document to search for id.
* @return {Node}
* @protected
*/
var byId = (ua.isIE || ua.isOpera) ?
function(id, doc) {
if (isString(id)) {
doc = doc || document;
var te = doc.getElementById(id);
// attributes.id.value is better than just id in case the
// user has a name=id inside a form
if (te && te.attributes.id.value == id) {
return te;
} else {
var elements = doc.all[id];
if (!elements || !elements.length) {
return elements;
}
// if more than 1, choose first with the correct id
var i=0;
while (te = elements[i++]) {
if (te.attributes.id.value == id) {
return te;
}
}
}
} else {
return id; // DomNode
}
} :
function(id, doc) {
return isString(id) ? (doc || document).getElementById(id) : id;
};
/**
* returns a unique DOM id which can be used to locate the node via byId().
* If the node already has an ID, it's used. If not, one is generated. Like
* IE's uniqueID property.
* @param {Node} node The element to create or fetch a unique ID for
* @return {String}
* @protected
*/
var getUid = function(node) {
var u = 'cfUnique' + (_counter++);
return (!node) ? u : ( node.id || node.uniqueID || (node.id = u) );
};
//
// the Deferred class, borrowed from Twisted Python and Dojo
//
/**
* A class that models a single response (past or future) to a question.
* Multiple callbacks and error handlers may be added. If the response was
* added in the past, adding callbacks has the effect of calling them
* immediately. In this way, Deferreds simplify thinking about synchronous
* vs. asynchronous programming in languages which don't have continuations
* or generators which might otherwise provide syntax for deferring
* operations.
* @param {function} canceller Optional A function to be called when the
* Deferred is canceled.
* @param {number} timeout Optional How long to wait (in ms) before errback
* is called with a timeout error. If no timeout is passed, the default
* is 1hr. Passing -1 will disable any timeout.
* @constructor
* @public
*/
Deferred = function(/*Function?*/ canceller, timeout){
// example:
// var deferred = new Deferred();
// setTimeout(function(){ deferred.callback({success: true}); }, 1000);
// return deferred;
this.chain = [];
this.id = _counter++;
this.fired = -1;
this.paused = 0;
this.results = [ null, null ];
this.canceller = canceller;
// FIXME(slightlyoff): is it really smart to be creating this many timers?
if (typeof timeout == 'number') {
if (timeout <= 0) {
timeout = 216000; // give it an hour
}
}
this._timer = setTimeout(
hitch(this, 'errback', new Error('timeout')),
(timeout || 10000)
);
this.silentlyCancelled = false;
};
/**
* Cancels a Deferred that has not yet received a value, or is waiting on
* another Deferred as its value. If a canceller is defined, the canceller
* is called. If the canceller did not return an error, or there was no
* canceller, then the errback chain is started.
* @public
*/
Deferred.prototype.cancel = function() {
var err;
if (this.fired == -1) {
if (this.canceller) {
err = this.canceller(this);
} else {
this.silentlyCancelled = true;
}
if (this.fired == -1) {
if ( !(err instanceof Error) ) {
var res = err;
var msg = 'Deferred Cancelled';
if (err && err.toString) {
msg += ': ' + err.toString();
}
err = new Error(msg);
err.dType = 'cancel';
err.cancelResult = res;
}
this.errback(err);
}
} else if (
(this.fired == 0) &&
(this.results[0] instanceof Deferred)
) {
this.results[0].cancel();
}
};
/**
* internal function for providing a result. If res is an instance of Error,
* we treat it like such and start the error chain.
* @param {Object|Error} res the result
* @private
*/
Deferred.prototype._resback = function(res) {
if (this._timer) {
clearTimeout(this._timer);
}
this.fired = res instanceof Error ? 1 : 0;
this.results[this.fired] = res;
this._fire();
};
/**
* determine if the deferred has already been resolved
* @return {boolean}
* @private
*/
Deferred.prototype._check = function() {
if (this.fired != -1) {
if (!this.silentlyCancelled) {
return 0;
}
this.silentlyCancelled = 0;
return 1;
}
return 0;
};
/**
* Begin the callback sequence with a non-error value.
* @param {Object|Error} res the result
* @public
*/
Deferred.prototype.callback = function(res) {
this._check();
this._resback(res);
};
/**
* Begin the callback sequence with an error result.
* @param {Error|string} res the result. If not an Error, it's treated as the
* message for a new Error.
* @public
*/
Deferred.prototype.errback = function(res) {
this._check();
if ( !(res instanceof Error) ) {
res = new Error(res);
}
this._resback(res);
};
/**
* Add a single function as the handler for both callback and errback,
* allowing you to specify a scope (unlike addCallbacks).
* @param {function|Object} cb A function. If cbfn is passed, the value of cb
* is treated as a scope
* @param {function|string} cbfn Optional A function or name of a function in
* the scope cb.
* @return {Deferred} this
* @public
*/
Deferred.prototype.addBoth = function(cb, cbfn) {
var enclosed = hitch.apply(window, arguments);
return this.addCallbacks(enclosed, enclosed);
};
/**
* Add a single callback to the end of the callback sequence. Add a function
* as the handler for successful resolution of the Deferred. May be called
* multiple times to register many handlers. Note that return values are
* chained if provided, so it's best for callback handlers not to return
* anything.
* @param {function|Object} cb A function. If cbfn is passed, the value of cb
* is treated as a scope
* @param {function|string} cbfn Optional A function or name of a function in
* the scope cb.
* @return {Deferred} this
* @public
*/
Deferred.prototype.addCallback = function(cb, cbfn /*...*/) {
return this.addCallbacks(hitch.apply(window, arguments));
};
/**
* Add a function as the handler for errors in the Deferred. May be called
* multiple times to add multiple error handlers.
* @param {function|Object} cb A function. If cbfn is passed, the value of cb
* is treated as a scope
* @param {function|string} cbfn Optional A function or name of a function in
* the scope cb.
* @return {Deferred} this
* @public
*/
Deferred.prototype.addErrback = function(cb, cbfn) {
return this.addCallbacks(null, hitch.apply(window, arguments));
};
/**
* Add a functions as handlers for callback and errback in a single shot.
* @param {function} callback A function
* @param {function} errback A function
* @return {Deferred} this
* @public
*/
Deferred.prototype.addCallbacks = function(callback, errback) {
this.chain.push([callback, errback]);
if (this.fired >= 0) {
this._fire();
}
return this;
};
/**
* when this Deferred is satisfied, pass it on to def, allowing it to run.
* @param {Deferred} def A deferred to add to the end of this Deferred in a chain
* @return {Deferred} this
* @public
*/
Deferred.prototype.chain = function(def) {
this.addCallbacks(def.callback, def.errback);
return this;
};
/**
* Used internally to exhaust the callback sequence when a result is
* available.
* @private
*/
Deferred.prototype._fire = function() {
var chain = this.chain;
var fired = this.fired;
var res = this.results[fired];
var cb = null;
while ((chain.length) && (!this.paused)) {
var f = chain.shift()[fired];
if (!f) {
continue;
}
var func = hitch(this, function() {
var ret = f(res);
//If no response, then use previous response.
if (typeof ret != undefStr) {
res = ret;
}
fired = res instanceof Error ? 1 : 0;
if (res instanceof Deferred) {
cb = function(res) {
this._resback(res);
// inlined from _pause()
this.paused--;
if ( (this.paused == 0) && (this.fired >= 0)) {
this._fire();
}
}
// inlined from _unpause
this.paused++;
}
});
try {
func.call(this);
} catch(err) {
fired = 1;
res = err;
}
}
this.fired = fired;
this.results[fired] = res;
if (cb && this.paused ) {
// this is for "tail recursion" in case the dependent
// deferred is already fired
res.addBoth(cb);
}
};
/////////////////////////////////////////////////////////////////////////////
// Plugin Initialization Class and Helper Functions
/////////////////////////////////////////////////////////////////////////////
var returnFalse = function() {
return false;
};
var cachedHasVideo;
var cachedHasAudio;
var contentTests = {
canvas: function() {
return !!(
ua.isChrome || ua.isSafari >= 3 || ua.isFF >= 3 || ua.isOpera >= 9.2
);
},
svg: function() {
return !!(ua.isChrome || ua.isSafari || ua.isFF || ua.isOpera);
},
postMessage: function() {
return (
!!window['postMessage'] ||
ua.isChrome ||
ua.isIE >= 8 ||
ua.isSafari >= 3 ||
ua.isFF >= 3 ||
ua.isOpera >= 9.2
);
},
// the spec isn't settled and nothing currently supports it
websocket: returnFalse,
'css-anim': function() {
// pretty much limited to WebKit's special transition and animation
// properties. Need to figure out a better way to triangulate this as
// FF3.x adds more of these properties in parallel.
return ua.isWebKit > 500;
},
// "working" video/audio tag?
video: function() {
if (typeof cachedHasVideo != undefStr) {
return cachedHasVideo;
}
// We haven't figured it out yet, so probe the <video> tag and cache the
// result.
var video = document.createElement('video');
return cachedHasVideo = (typeof video['play'] != undefStr);
},
audio: function() {
if (typeof cachedHasAudio != undefStr) {
return cachedHasAudio;
}
var audio = document.createElement('audio');
return cachedHasAudio = (typeof audio['play'] != undefStr);
},
'video-theora': function() {
return contentTests.video() && (ua.isChrome || ua.isFF > 3);
},
'video-h264': function() {
return contentTests.video() && (ua.isChrome || ua.isSafari >= 4);
},
'audio-vorbis': function() {
return contentTests.audio() && (ua.isChrome || ua.isFF > 3);
},
'audio-mp3': function() {
return contentTests.audio() && (ua.isChrome || ua.isSafari >= 4);
},
// can we implement RPC over available primitives?
rpc: function() {
// on IE we need the src to be on the same domain or we need postMessage
// to work. Since we can't count on the src being same-domain, we look
// for things that have postMessage. We may re-visit this later and add
// same-domain checking and cross-window-call-as-postMessage-replacement
// code.
// use "!!" to avoid null-is-an-object weirdness
return !!window['postMessage'];
},
sql: function() {
// HTML 5 databases
return !!window['openDatabase'];
},
storage: function(){
// DOM storage
// IE8, Safari, etc. support "localStorage", FF supported "globalStorage"
return !!window['globalStorage'] || !!window['localStorage'];
}
};
// isIE, isFF, isWebKit, etc.
forEach([
'isOpera', 'isWebKit', 'isChrome', 'isKhtml', 'isSafari',
'isGecko', 'isFF', 'isIE'
],
function(name) {
contentTests[name] = function() {
return !!ua[name];
};
}
);
/**
* Checks the list of requirements to determine if the current host browser
* meets them natively. Primarialy relies on the contentTests array.
* @param {Array} reqs A list of tests, either names of test functions in
* contentTests or functions to execute.
* @return {boolean}
* @private
*/
var testRequirements = function(reqs) {
// never use CF on Chrome or Safari
if (ua.isChrome || ua.isSafari) {
return true;
}
var allMatch = true;
if (!reqs) {
return false;
}
forEach(reqs, function(i) {
var matches = false;
if (isFunction(i)) {
// support custom test functions
matches = i();
} else {
// else it's a lookup by name
matches = (!!contentTests[i] && contentTests[i]());
}
allMatch = allMatch && matches;
});
return allMatch;
};
var cachedAvailable;
/**
* Checks to find out if ChromeFrame is available as a plugin
* @return {Boolean}
* @private
*/
var isCfAvailable = function() {
if (typeof cachedAvailable != undefStr) {
return cachedAvailable;
}
cachedAvailable = false;
var p = n.plugins;
if (typeof window['ActiveXObject'] != undefStr) {
try {
var i = new ActiveXObject('ChromeTab.ChromeFrame');
if (i) {
cachedAvailable = true;
}
} catch(e) {
log('ChromeFrame not available, error:', e.message);
// squelch
}
} else {
for (var x = 0; x < p.length; x++) {
if (p[x].name.indexOf('Google Chrome Frame') == 0) {
cachedAvailable = true;
break;
}
}
}
return cachedAvailable;
};
/**
* Creates a <param> element with the specified name and value. If a parent
* is provided, the <param> element is appended to it.
* @param {string} name The name of the param
* @param {string} value The value
* @param {Node} parent Optional parent element
* @return {Boolean}
* @private
*/
var param = function(name, value, parent) {
var p = document.createElement('param');
p.setAttribute('name', name);
p.setAttribute('value', value);
if (parent) {
parent.appendChild(p);
}
return p;
};
/** @type {boolean} */
var cfStyleTagInjected = false;
/**
* Creates a style sheet in the document which provides default styling for
* ChromeFrame instances. Successive calls should have no additive effect.
* @private
*/
var injectCFStyleTag = function() {
if (cfStyleTagInjected) {
// once and only once
return;
}
try {
var rule = ['.chromeFrameDefaultStyle {',
'width: 400px;',
'height: 300px;',
'padding: 0;',
'margin: 0;',
'}'].join('');
var ss = document.createElement('style');
ss.setAttribute('type', 'text/css');
if (ss.styleSheet) {
ss.styleSheet.cssText = rule;
} else {
ss.appendChild(document.createTextNode(rule));
}
var h = document.getElementsByTagName('head')[0];
if (h.firstChild) {
h.insertBefore(ss, h.firstChild);
} else {
h.appendChild(ss);
}
cfStyleTagInjected = true;
} catch (e) {
// squelch
// FIXME(slightlyoff): log? retry?
}
};
/**
* Plucks properties from the passed arguments and sets them on the passed
* DOM node
* @param {Node} node The node to set properties on
* @param {Object} args A map of user-specified properties to set
* @private
*/
var setProperties = function(node, args) {
injectCFStyleTag();
var srcNode = byId(args['node']);
node.id = args['id'] || (srcNode ? srcNode['id'] || getUid(srcNode) : '');
// TODO(slightlyoff): Opera compat? need to test there
var cssText = args['cssText'] || '';
node.style.cssText = ' ' + cssText;
var classText = args['className'] || '';
node.className = 'chromeFrameDefaultStyle ' + classText;
// default if the browser doesn't so we don't show sad-tab
var src = args['src'] || 'about:blank';
if (ua.isIE || ua.isOpera) {
node.src = src;
} else {
// crazyness regarding when things are set in NPAPI
node.setAttribute('src', src);
}
if (srcNode) {
srcNode.parentNode.replaceChild(node, srcNode);
}
};
/**
* Creates a plugin instance, taking named parameters from the passed args.
* @param {Object} args A bag of configuration properties, including values
* like 'node', 'cssText', 'className', 'id', 'src', etc.
* @return {Node}
* @private
*/
var makeCFPlugin = function(args) {
var el; // the element
if (!ua.isIE) {
el = document.createElement('object');
el.setAttribute("type", "application/chromeframe");
} else {
var dummy = document.createElement('span');
dummy.innerHTML = [
'<object codeBase="//www.google.com"',
"type='application/chromeframe'",
'classid="CLSID:E0A900DF-9611-4446-86BD-4B1D47E7DB2A"></object>'
].join(' ');
el = dummy.firstChild;
}
setProperties(el, args);
return el;
};
/**
* Creates an iframe in lieu of a ChromeFrame plugin, taking named parameters
* from the passed args.
* @param {Object} args A bag of configuration properties, including values
* like 'node', 'cssText', 'className', 'id', 'src', etc.
* @return {Node}
* @private
*/
var makeCFIframe = function(args) {
var el = document.createElement('iframe');
setProperties(el, args);
// FIXME(slightlyoff):
// This is where we'll need to slot in "don't fire load events for
// fallback URL" logic.
listen(el, 'load', hitch(el, '_dispatch', 'load'));
return el;
};
var msgPrefix = 'CFInstance.rpc:';
/**
* A class that provides the ability for widget-mode hosted content to more
* easily call hosting-page exposed APIs (and vice versa). It builds upon the
* message-passing nature of ChromeFrame to route messages to the other
* side's RPC host and coordinate events such as 'RPC readyness', buffering
* calls until both sides indicate they are ready to participate.
* @constructor
* @public
*/
var RPC = function(instance) {
this.initDeferred = new Deferred();
this.instance = instance;
instance.listen('message', hitch(this, '_handleMessage'));
this._localExposed = {};
this._doWithAckCallbacks = {};
this._open = false;
this._msgBacklog = [];
this._initialized = false;
this._exposeMsgBacklog = [];
this._exposed = false;
this._callRemoteMsgBacklog = [];
this._inFlight = {};
var sendLoadMsg = hitch(this, function(evt) {
this.doWithAck('load').addCallback(this, function() {
this._open = true;
this._postMessageBacklog();
});
});
if (instance['tagName']) {
instance.listen('load', sendLoadMsg);
} else {
sendLoadMsg();
}
};
RPC.prototype._postMessageBacklog = function() {
if (this._open) {
// forEach(this._msgBacklog, this._postMessage, this);
// this._msgBacklog = [];
while (this._msgBacklog.length) {
var msg = this._msgBacklog.shift();
this._postMessage(msg);
}
}
};
RPC.prototype._postMessage = function(msg, force) {
if (!force && !this._open) {
this._msgBacklog.push(msg);
} else {
// FIXME(slightlyoff): need to check domains list here!
this.instance.postMessage(msgPrefix + msg, '*');
}
};
RPC.prototype._doWithAck = function(what) {
this._postMessage('doWithAckCallback:' + what, what == 'load');
};
RPC.prototype.doWithAck = function(what) {
var d = new Deferred();
this._doWithAckCallbacks[what] = d;
this._postMessage('doWithAck:' + what, what == 'load');
return d;
};
RPC.prototype._handleMessage = function(evt, stopper) {
var d = String(evt.data);
if (d.indexOf(msgPrefix) != 0) {
// not for us, allow the event dispatch to continue...
return;
}
// ...else we're the end of the line for this event
stopper();
// see if we know what type of message it is
d = d.substr(msgPrefix.length);
var cIndex = d.indexOf(':');
var type = d.substr(0, cIndex);
if (type == 'doWithAck') {
this._doWithAck(d.substr(cIndex + 1));
return;
}
var msgBody = d.substr(cIndex + 1);
if (type == 'doWithAckCallback') {
this._doWithAckCallbacks[msgBody].callback(1);
return;
}
if (type == 'init') {
return;
}
// All the other stuff we can do uses a JSON payload.
var obj = fromJson(msgBody);
if (type == 'callRemote') {
if (obj.method && obj.params && obj.id) {
var ret = {
success: 0,
returnId: obj.id
};
try {
// Undefined isn't valid JSON, so use null as default value.
ret.value = this._localExposed[ obj.method ](evt, obj) || null;
ret.success = 1;
} catch(e) {
ret.error = e.message;
}
this._postMessage('callReturn:' + toJson(ret));
}
}
if (type == 'callReturn') {
// see if we're waiting on an outstanding RPC call, which
// would be identified by returnId.
var rid = obj['returnId'];
if (!rid) {
// throw an error?
return;
}
var callWrap = this._inFlight[rid];
if (!callWrap) {
return;
}
if (obj.success) {
callWrap.d.callback(obj['value'] || 1);
} else {
callWrap.d.errback(new Error(obj['error'] || 'unspecified RPC error'));
}
delete this._inFlight[rid];
}
};
/**
* Makes a method visible to be called
* @param {string} name The name to expose the method at.
* @param {Function|string} method The function (or name of the function) to
* expose. If a name is provided, it's looked up from the passed scope.
* If no scope is provided, the global scope is queried for a function
* with that name.
* @param {Object} scope Optional A scope to bind the passed method to. If
* the method parameter is specified by a string, the method is both
* located on the passed scope and bound to it.
* @param {Array} domains Optional A list of domains in
* 'http://example.com:8080' format which may call the given method.
* Currently un-implemented.
* @public
*/
RPC.prototype.expose = function(name, method, scope, domains) {
scope = scope || window;
method = isString(method) ? scope[method] : method;
// local call proxy that the other side will hit when calling our method
this._localExposed[name] = function(evt, obj) {
return method.apply(scope, obj.params);
};
if (!this._initialized) {
this._exposeMsgBacklog.push(arguments);
return;
}
var a = [name, method, scope, domains];
this._sendExpose.apply(this, a);
};
RPC.prototype._sendExpose = function(name) {
// now tell the other side that we're advertising this method
this._postMessage('expose:' + toJson({ name: name }));
};
/**
* Calls a remote method asynchronously and returns a Deferred object
* representing the response.
* @param {string} method Name of the method to call. Should be the same name
* which the other side has expose()'d.
* @param {Array} params Optional A list of arguments to pass to the called
* method. All elements in the list must be cleanly serializable to
* JSON.
* @param {CFInstance.Deferred} deferred Optional A Deferred to use for
* reporting the response of the call. If no deferred is passed, a new
* Deferred is created and returned.
* @return {CFInstance.Deferred}
* @public
*/
RPC.prototype.callRemote = function(method, params, timeout, deferred) {
var d = deferred || new Deferred(null, timeout || -1);
if (!this._exposed) {
var args = toArray(arguments);
args.length = 3;
args.push(d);
this._callRemoteMsgBacklog.push(args);
return d;
}
if (!method) {
d.errback('no method provided!');
return d;
}
var id = msgPrefix + (_counter++);
// JSON-ify the whole bundle
var callWrapper = {
method: String(method),
params: params || [],
id: id
};
var callJson = toJson(callWrapper);
callWrapper.d = d;
this._inFlight[id] = callWrapper;
this._postMessage('callRemote:' + callJson);
return d;
};
/**
* Tells the other side of the connection that we're ready to start receiving
* calls. Returns a Deferred that is called back when both sides have
* initialized and any backlogged messages have been sent. RPC users should
* generally work to make sure that they call expose() on all of the methods
* they'd like to make available to the other side *before* calling init()
* @return {CFInstance.Deferred}
* @public
*/
RPC.prototype.init = function() {
var d = this.initDeferred;
this.doWithAck('init').addCallback(this, function() {
// once the init floodgates are open, send our backlogs one at a time,
// with a little lag in the middle to prevent ordering problems
this._initialized = true;
while (this._exposeMsgBacklog.length) {
this.expose.apply(this, this._exposeMsgBacklog.shift());
}
setTimeout(hitch(this, function(){
this._exposed = true;
while (this._callRemoteMsgBacklog.length) {
this.callRemote.apply(this, this._callRemoteMsgBacklog.shift());
}
d.callback(1);
}), 30);
});
return d;
};
// CFInstance design notes:
//
// The CFInstance constructor is only ever used in host environments. In
// content pages (things hosted by a ChromeFrame instance), CFInstance
// acts as a singleton which provides services like RPC for communicating
// with it's mirror-image object in the hosting environment. We want the
// same methods and properties to be available on *instances* of
// CFInstance objects in the host env as on the singleton in the hosted
// content, despite divergent implementation.
//
// Further complicating things, CFInstance may specialize behavior
// internally based on whether or not it is communicationg with a fallback
// iframe or a 'real' ChromeFrame instance.
var CFInstance; // forward declaration
var h = window['externalHost'];
var inIframe = (window.parent != window);
if (inIframe) {
h = window.parent;
}
var normalizeTarget = function(targetOrigin) {
var l = window.location;
if (!targetOrigin) {
if (l.protocol != 'file:') {
targetOrigin = l.protocol + '//' + l.host + "/";
} else {
// TODO(slightlyoff):
// is this secure enough? Is there another way to get messages
// flowing reliably across file-hosted documents?
targetOrigin = '*';
}
}
return targetOrigin;
};
var postMessageToDest = function(dest, msg, targetOrigin) {
return dest.postMessage(msg, normalizeTarget(targetOrigin));
};
if (h) {
//
// We're loaded inside a ChromeFrame widget (or something that should look
// like we were).
//
CFInstance = {};
installEvtSys(CFInstance);
// FIXME(slightlyoff):
// passing a target origin to externalHost's postMessage seems b0rked
// right now, so pass null instead. Will re-enable hitch()'d variant
// once that's fixed.
// CFInstance.postMessage = hitch(null, postMessageToDest, h);
CFInstance.postMessage = function(msg, targetOrigin) {
return h.postMessage(msg,
(inIframe ? normalizeTarget(targetOrigin) : null) );
};
// Attach to the externalHost's onmessage to proxy it in to CFInstance's
// onmessage.
var dispatchMsg = function(evt) {
try {
CFInstance._dispatch('message', evt);
} catch(e) {
log(e);
// squelch
}
};
if (inIframe) {
listen(window, 'message', dispatchMsg);
} else {
h.onmessage = dispatchMsg;
}
CFInstance.rpc = new RPC(CFInstance);
_loadedListenerList.push(function(evt) {
CFInstance._dispatch('load', evt);
});
} else {
//
// We're the host document.
//
var installProperties = function(instance, args) {
var s = instance.supportedEvents = ['load', 'message'];
instance._msgPrefix = 'CFMessage:';
installEvtSys(instance);
instance.log = log;
// set up an RPC instance
instance.rpc = new RPC(instance);
forEach(s, function(evt) {
var l = args['on' + evt];
if (l) {
instance.listen(evt, l);
}
});
var contentWindow = instance.contentWindow;
// if it doesn't have a postMessage, route to/from the iframe's built-in
if (typeof instance['postMessage'] == undefStr && !!contentWindow) {
instance.postMessage = hitch(null, postMessageToDest, contentWindow);
listen(window, 'message', function(evt) {
if (evt.source == contentWindow) {
instance._dispatch('message', evt);
}
});
}
return instance;
};
/**
* A class whose instances correspond to ChromeFrame instances. Passing an
* arguments object to CFInstance helps parameterize the instance.
* @constructor
* @public
*/
CFInstance = function(args) {
args = args || {};
var instance;
var success = false;
// If we've been passed a CFInstance object as our source node, just
// re-use it.
if (args['node']) {
var n = byId(args['node']);
// Look for CF-specific properties.
if (n && n.tagName == 'OBJECT' && n.success && n.rpc) {
// Navigate, set styles, etc.
setProperties(n, args);
return n;
}
}
var force = !!args['forcePlugin'];
if (!force && testRequirements(args['requirements'])) {
instance = makeCFIframe(args);
success = true;
} else if (isCfAvailable()) {
instance = makeCFPlugin(args);
success = true;
} else {
// else create an iframe but load the failure content and
// not the 'normal' content
// grab the fallback URL, and if none, use the 'click here
// to install ChromeFrame' URL. Note that we only support
// polling for install success if we're using the default
// URL
var fallback = '//www.google.com/chromeframe';
args.src = args['fallback'] || fallback;
instance = makeCFIframe(args);
if (args.src == fallback) {
// begin polling for install success.
// TODO(slightlyoff): need to prevent firing of onload hooks!
// TODO(slightlyoff): implement polling
// TODO(slightlyoff): replacement callback?
// TODO(slightlyoff): add flag to disable this behavior
}
}
instance.success = success;
installProperties(instance, args);
return instance;
};
// compatibility shims for development-time. These mirror the methods that
// are created on the CFInstance singleton if we detect that we're running
// inside of CF.
if (!CFInstance['postMessage']) {
CFInstance.postMessage = function() {
var args = toArray(arguments);
args.unshift('CFInstance.postMessage:');
log.apply(null, args);
};
CFInstance.listen = function() {
// this space intentionally left blank
};
}
}
// expose some properties
CFInstance.ua = ua;
CFInstance._documentLoaded = documentLoaded;
CFInstance.contentTests = contentTests;
CFInstance.isAvailable = function(requirements) {
var hasCf = isCfAvailable();
return requirements ? (hasCf || testRequirements(requirements)) : hasCf;
};
CFInstance.Deferred = Deferred;
CFInstance.toJson = toJson;
CFInstance.fromJson = fromJson;
CFInstance.log = log;
// expose CFInstance to the external scope. We've already checked to make
// sure we're not going to blow existing objects away.
scope.CFInstance = CFInstance;
})( this['ChromeFrameScope'] || this );
// vim: shiftwidth=2:et:ai:tabstop=2