/* Copyright (c) 2010, Yahoo! Inc. All rights reserved. Code licensed under the BSD License: http://developer.yahoo.com/yui/license.html version: 2.8.2r1 */ /** * Provides a mechanism to fetch remote resources and * insert them into a document * @module get * @requires yahoo */ /** * Fetches and inserts one or more script or link nodes into the document * @namespace YAHOO.util * @class YAHOO.util.Get */ YAHOO.util.Get = function() { /** * hash of queues to manage multiple requests * @property queues * @private */ var queues={}, /** * queue index used to generate transaction ids * @property qidx * @type int * @private */ qidx=0, /** * node index used to generate unique node ids * @property nidx * @type int * @private */ nidx=0, // ridx=0, // sandboxFrame=null, /** * interal property used to prevent multiple simultaneous purge * processes * @property purging * @type boolean * @private */ purging=false, ua=YAHOO.env.ua, lang=YAHOO.lang; /** * Generates an HTML element, this is not appended to a document * @method _node * @param type {string} the type of element * @param attr {string} the attributes * @param win {Window} optional window to create the element in * @return {HTMLElement} the generated node * @private */ var _node = function(type, attr, win) { var w = win || window, d=w.document, n=d.createElement(type); for (var i in attr) { if (attr[i] && YAHOO.lang.hasOwnProperty(attr, i)) { n.setAttribute(i, attr[i]); } } return n; }; /** * Generates a link node * @method _linkNode * @param url {string} the url for the css file * @param win {Window} optional window to create the node in * @return {HTMLElement} the generated node * @private */ var _linkNode = function(url, win, attributes) { var o = { id: "yui__dyn_" + (nidx++), type: "text/css", rel: "stylesheet", href: url }; if (attributes) { lang.augmentObject(o, attributes); } return _node("link", o, win); }; /** * Generates a script node * @method _scriptNode * @param url {string} the url for the script file * @param win {Window} optional window to create the node in * @return {HTMLElement} the generated node * @private */ var _scriptNode = function(url, win, attributes) { var o = { id: "yui__dyn_" + (nidx++), type: "text/javascript", src: url }; if (attributes) { lang.augmentObject(o, attributes); } return _node("script", o, win); }; /** * Returns the data payload for callback functions * @method _returnData * @private */ var _returnData = function(q, msg) { return { tId: q.tId, win: q.win, data: q.data, nodes: q.nodes, msg: msg, purge: function() { _purge(this.tId); } }; }; var _get = function(nId, tId) { var q = queues[tId], n = (lang.isString(nId)) ? q.win.document.getElementById(nId) : nId; if (!n) { _fail(tId, "target node not found: " + nId); } return n; }; /* * The request failed, execute fail handler with whatever * was accomplished. There isn't a failure case at the * moment unless you count aborted transactions * @method _fail * @param id {string} the id of the request * @private */ var _fail = function(id, msg) { YAHOO.log("get failure: " + msg, "warn", "Get"); var q = queues[id]; // execute failure callback if (q.onFailure) { var sc=q.scope || q.win; q.onFailure.call(sc, _returnData(q, msg)); } }; /** * The request is complete, so executing the requester's callback * @method _finish * @param id {string} the id of the request * @private */ var _finish = function(id) { YAHOO.log("Finishing transaction " + id); var q = queues[id]; q.finished = true; if (q.aborted) { var msg = "transaction " + id + " was aborted"; _fail(id, msg); return; } // execute success callback if (q.onSuccess) { var sc=q.scope || q.win; q.onSuccess.call(sc, _returnData(q)); } }; /** * Timeout detected * @method _timeout * @param id {string} the id of the request * @private */ var _timeout = function(id) { YAHOO.log("Timeout " + id, "info", "get"); var q = queues[id]; if (q.onTimeout) { var sc=q.scope || q; q.onTimeout.call(sc, _returnData(q)); } }; /** * Loads the next item for a given request * @method _next * @param id {string} the id of the request * @param loaded {string} the url that was just loaded, if any * @private */ var _next = function(id, loaded) { YAHOO.log("_next: " + id + ", loaded: " + loaded, "info", "Get"); var q = queues[id]; if (q.timer) { // Y.log('cancel timer'); q.timer.cancel(); } if (q.aborted) { var msg = "transaction " + id + " was aborted"; _fail(id, msg); return; } if (loaded) { q.url.shift(); if (q.varName) { q.varName.shift(); } } else { // This is the first pass: make sure the url is an array q.url = (lang.isString(q.url)) ? [q.url] : q.url; if (q.varName) { q.varName = (lang.isString(q.varName)) ? [q.varName] : q.varName; } } var w=q.win, d=w.document, h=d.getElementsByTagName("head")[0], n; if (q.url.length === 0) { // Safari 2.x workaround - There is no way to know when // a script is ready in versions of Safari prior to 3.x. // Adding an extra node reduces the problem, but doesn't // eliminate it completely because the browser executes // them asynchronously. if (q.type === "script" && ua.webkit && ua.webkit < 420 && !q.finalpass && !q.varName) { // Add another script node. This does not guarantee that the // scripts will execute in order, but it does appear to fix the // problem on fast connections more effectively than using an // arbitrary timeout. It is possible that the browser does // block subsequent script execution in this case for a limited // time. var extra = _scriptNode(null, q.win, q.attributes); extra.innerHTML='YAHOO.util.Get._finalize("' + id + '");'; q.nodes.push(extra); h.appendChild(extra); } else { _finish(id); } return; } var url = q.url[0]; // if the url is undefined, this is probably a trailing comma problem in IE if (!url) { q.url.shift(); YAHOO.log('skipping empty url'); return _next(id); } YAHOO.log("attempting to load " + url, "info", "Get"); if (q.timeout) { // Y.log('create timer'); q.timer = lang.later(q.timeout, q, _timeout, id); } if (q.type === "script") { n = _scriptNode(url, w, q.attributes); } else { n = _linkNode(url, w, q.attributes); } // track this node's load progress _track(q.type, n, id, url, w, q.url.length); // add the node to the queue so we can return it to the user supplied callback q.nodes.push(n); // add it to the head or insert it before 'insertBefore' if (q.insertBefore) { var s = _get(q.insertBefore, id); if (s) { s.parentNode.insertBefore(n, s); } } else { h.appendChild(n); } YAHOO.log("Appending node: " + url, "info", "Get"); // FireFox does not support the onload event for link nodes, so there is // no way to make the css requests synchronous. This means that the css // rules in multiple files could be applied out of order in this browser // if a later request returns before an earlier one. Safari too. if ((ua.webkit || ua.gecko) && q.type === "css") { _next(id, url); } }; /** * Removes processed queues and corresponding nodes * @method _autoPurge * @private */ var _autoPurge = function() { if (purging) { return; } purging = true; for (var i in queues) { var q = queues[i]; if (q.autopurge && q.finished) { _purge(q.tId); delete queues[i]; } } purging = false; }; /** * Removes the nodes for the specified queue * @method _purge * @private */ var _purge = function(tId) { if (queues[tId]) { var q = queues[tId], nodes = q.nodes, l = nodes.length, d = q.win.document, h = d.getElementsByTagName("head")[0], sib, i, node, attr; if (q.insertBefore) { sib = _get(q.insertBefore, tId); if (sib) { h = sib.parentNode; } } for (i=0; i= 420) { n.addEventListener("load", function() { YAHOO.log(id + " DOM2 onload " + url, "info", "Get"); f(id, url); }); // Nothing can be done with Safari < 3.x except to pause and hope // for the best, particularly after last script is inserted. The // scripts will always execute in the order they arrive, not // necessarily the order in which they were inserted. To support // script nodes with complete reliability in these browsers, script // nodes either need to invoke a function in the window once they // are loaded or the implementer needs to provide a well-known // property that the utility can poll for. } else { // Poll for the existence of the named variable, if it // was supplied. var q = queues[id]; if (q.varName) { var freq=YAHOO.util.Get.POLL_FREQ; YAHOO.log("Polling for " + q.varName[0]); q.maxattempts = YAHOO.util.Get.TIMEOUT/freq; q.attempts = 0; q._cache = q.varName[0].split("."); q.timer = lang.later(freq, q, function(o) { var a=this._cache, l=a.length, w=this.win, i; for (i=0; i this.maxattempts) { var msg = "Over retry limit, giving up"; q.timer.cancel(); _fail(id, msg); } else { YAHOO.log(a[i] + " failed, retrying"); } return; } } YAHOO.log("Safari poll complete"); q.timer.cancel(); f(id, url); }, null, true); } else { lang.later(YAHOO.util.Get.POLL_FREQ, null, f, [id, url]); } } } // FireFox and Opera support onload (but not DOM2 in FF) handlers for // script nodes. Opera, but not FF, supports the onload event for link // nodes. } else { n.onload = function() { YAHOO.log(id + " onload " + url, "info", "Get"); f(id, url); }; } }; return { /** * The default poll freqency in ms, when needed * @property POLL_FREQ * @static * @type int * @default 10 */ POLL_FREQ: 10, /** * The number of request required before an automatic purge. * property PURGE_THRESH * @static * @type int * @default 20 */ PURGE_THRESH: 20, /** * The length time to poll for varName when loading a script in * Safari 2.x before the transaction fails. * property TIMEOUT * @static * @type int * @default 2000 */ TIMEOUT: 2000, /** * Called by the the helper for detecting script load in Safari * @method _finalize * @param id {string} the transaction id * @private */ _finalize: function(id) { YAHOO.log(id + " finalized ", "info", "Get"); lang.later(0, null, _finish, id); }, /** * Abort a transaction * @method abort * @param {string|object} either the tId or the object returned from * script() or css() */ abort: function(o) { var id = (lang.isString(o)) ? o : o.tId; var q = queues[id]; if (q) { YAHOO.log("Aborting " + id, "info", "Get"); q.aborted = true; } }, /** * Fetches and inserts one or more script nodes into the head * of the current document or the document in a specified window. * * @method script * @static * @param url {string|string[]} the url or urls to the script(s) * @param opts {object} Options: *
*
onSuccess
*
* callback to execute when the script(s) are finished loading * The callback receives an object back with the following * data: *
*
win
*
the window the script(s) were inserted into
*
data
*
the data object passed in when the request was made
*
nodes
*
An array containing references to the nodes that were * inserted
*
purge
*
A function that, when executed, will remove the nodes * that were inserted
*
*
*
*
onFailure
*
* callback to execute when the script load operation fails * The callback receives an object back with the following * data: *
*
win
*
the window the script(s) were inserted into
*
data
*
the data object passed in when the request was made
*
nodes
*
An array containing references to the nodes that were * inserted successfully
*
purge
*
A function that, when executed, will remove any nodes * that were inserted
*
*
*
*
onTimeout
*
* callback to execute when a timeout occurs. * The callback receives an object back with the following * data: *
*
win
*
the window the script(s) were inserted into
*
data
*
the data object passed in when the request was made
*
nodes
*
An array containing references to the nodes that were * inserted
*
purge
*
A function that, when executed, will remove the nodes * that were inserted
*
*
*
*
scope
*
the execution context for the callbacks
*
win
*
a window other than the one the utility occupies
*
autopurge
*
* setting to true will let the utilities cleanup routine purge * the script once loaded *
*
data
*
* data that is supplied to the callback when the script(s) are * loaded. *
*
varName
*
* variable that should be available when a script is finished * loading. Used to help Safari 2.x and below with script load * detection. The type of this property should match what was * passed into the url parameter: if loading a single url, a * string can be supplied. If loading multiple scripts, you * must supply an array that contains the variable name for * each script. *
*
insertBefore
*
node or node id that will become the new node's nextSibling
*
*
charset
*
Node charset, deprecated, use 'attributes'
*
attributes
*
A hash of attributes to apply to dynamic nodes.
*
timeout
*
Number of milliseconds to wait before aborting and firing the timeout event
*
         * // assumes yahoo, dom, and event are already on the page
         *   YAHOO.util.Get.script(
         *   ["http://yui.yahooapis.com/2.7.0/build/dragdrop/dragdrop-min.js",
         *    "http://yui.yahooapis.com/2.7.0/build/animation/animation-min.js"], {
         *     onSuccess: function(o) {
         *       YAHOO.log(o.data); // foo
         *       new YAHOO.util.DDProxy("dd1"); // also new o.reference("dd1"); would work
         *       this.log("won't cause error because YAHOO is the scope");
         *       this.log(o.nodes.length === 2) // true
         *       // o.purge(); // optionally remove the script nodes immediately
         *     },
         *     onFailure: function(o) {
         *       YAHOO.log("transaction failed");
         *     },
         *     data: "foo",
         *     timeout: 10000, // 10 second timeout
         *     scope: YAHOO,
         *     // win: otherframe // target another window/frame
         *     autopurge: true // allow the utility to choose when to remove the nodes
         *   });
         * 
* @return {tId: string} an object containing info about the transaction */ script: function(url, opts) { return _queue("script", url, opts); }, /** * Fetches and inserts one or more css link nodes into the * head of the current document or the document in a specified * window. * @method css * @static * @param url {string} the url or urls to the css file(s) * @param opts Options: *
*
onSuccess
*
* callback to execute when the css file(s) are finished loading * The callback receives an object back with the following * data: *
win
*
the window the link nodes(s) were inserted into
*
data
*
the data object passed in when the request was made
*
nodes
*
An array containing references to the nodes that were * inserted
*
purge
*
A function that, when executed, will remove the nodes * that were inserted
*
*
* *
scope
*
the execution context for the callbacks
*
win
*
a window other than the one the utility occupies
*
data
*
* data that is supplied to the callbacks when the nodes(s) are * loaded. *
*
insertBefore
*
node or node id that will become the new node's nextSibling
*
charset
*
Node charset, deprecated, use 'attributes'
*
attributes
*
A hash of attributes to apply to dynamic nodes.
* *
         *      YAHOO.util.Get.css("http://yui.yahooapis.com/2.7.0/build/menu/assets/skins/sam/menu.css");
         * 
*
         *      YAHOO.util.Get.css(["http://yui.yahooapis.com/2.7.0/build/menu/assets/skins/sam/menu.css",
         *                          "http://yui.yahooapis.com/2.7.0/build/logger/assets/skins/sam/logger.css"]);
         * 
* @return {tId: string} an object containing info about the transaction */ css: function(url, opts) { return _queue("css", url, opts); } }; }(); YAHOO.register("get", YAHOO.util.Get, {version: "2.8.2r1", build: "7"});