org.wings.js.yui.get.get.js Maven / Gradle / Ivy
The newest version!
/*
Copyright (c) 2011, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.com/yui/license.html
version: 2.9.0
*/
/**
* Provides a mechanism to fetch remote resources and
* insert them into a document
* This utility can fetch JavaScript and CSS files, inserting script
* tags for script and link tags for CSS. Note, this
* is done via the normal browser mechanisms for inserting
* these resources and making the content available to
* code that would access it. Be careful when retreiving
* remote resources. Only use this utility to fetch
* files from sites you trust.
*
* @module get
* @requires yahoo
*/
/**
* Fetches and inserts one or more script or link nodes into the document.
* This utility can fetch JavaScript and CSS files, inserting script
* tags for script and link tags for CSS. Note, this
* is done via the normal browser mechanisms for inserting
* these resources and making the content available to
* code that would access it. Be careful when retreiving
* remote resources. Only use this utility to fetch
* files from sites you trust.
*
* @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,
/**
* interal property used to prevent multiple simultaneous purge
* processes
* @property purging
* @type boolean
* @private
*/
_purging=false,
ua=YAHOO.env.ua,
lang=YAHOO.lang,
_fail,
_purge,
_track,
/**
* 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
*/
_node = function(type, attr, win) {
var w = win || window, d=w.document, n=d.createElement(type), i;
for (i in attr) {
if (attr.hasOwnProperty(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
*/
_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
*/
_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
*/
_returnData = function(q, msg) {
return {
tId: q.tId,
win: q.win,
data: q.data,
nodes: q.nodes,
msg: msg,
purge: function() {
_purge(this.tId);
}
};
},
_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 is complete, so executing the requester's callback
* @method _finish
* @param id {string} the id of the request
* @private
*/
_finish = function(id) {
var q = queues[id], msg, context;
q.finished = true;
if (q.aborted) {
msg = "transaction " + id + " was aborted";
_fail(id, msg);
return;
}
// execute success callback
if (q.onSuccess) {
context = q.scope || q.win;
q.onSuccess.call(context, _returnData(q));
}
},
/**
* Timeout detected
* @method _timeout
* @param id {string} the id of the request
* @private
*/
_timeout = function(id) {
var q = queues[id], context;
if (q.onTimeout) {
context = q.scope || q;
q.onTimeout.call(context, _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
*/
_next = function(id, loaded) {
var q = queues[id], w=q.win, d=w.document, h=d.getElementsByTagName("head")[0],
n, msg, url, s, extra;
if (q.timer) {
// Y.log('cancel timer');
q.timer.cancel();
}
if (q.aborted) {
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;
}
}
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.
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;
}
url = q.url[0];
// if the url is undefined, this is probably a trailing comma problem in IE
if (!url) {
q.url.shift();
return _next(id);
}
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) {
s = _get(q.insertBefore, id);
if (s) {
s.parentNode.insertBefore(n, s);
}
} else {
h.appendChild(n);
}
// 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
*/
_autoPurge = function() {
if (_purging) {
return;
}
_purging = true;
var i, q;
for (i in queues) {
if (queues.hasOwnProperty(i)) {
q = queues[i];
if (q.autopurge && q.finished) {
_purge(q.tId);
delete queues[i];
}
}
}
_purging = false;
},
/**
* Saves the state for the request and begins loading
* the requested urls
* @method queue
* @param type {string} the type of node to insert
* @param url {string} the url to load
* @param opts the hash of options for this request
* @private
*/
_queue = function(type, url, opts) {
var id = "q" + (qidx++), q;
opts = opts || {};
if (qidx % YAHOO.util.Get.PURGE_THRESH === 0) {
_autoPurge();
}
queues[id] = lang.merge(opts, {
tId: id,
type: type,
url: url,
finished: false,
aborted: false,
nodes: []
});
q = queues[id];
q.win = q.win || window;
q.scope = q.scope || q.win;
q.autopurge = ("autopurge" in q) ? q.autopurge :
(type === "script") ? true : false;
q.attributes = q.attributes || {};
q.attributes.charset = opts.charset || q.attributes.charset || 'utf-8';
lang.later(0, q, _next, id);
return {
tId: id
};
};
/**
* Detects when a node has been loaded. In the case of
* script nodes, this does not guarantee that contained
* script is ready to use.
* @method _track
* @param type {string} the type of node to track
* @param n {HTMLElement} the node to track
* @param id {string} the id of the request
* @param url {string} the url that is being loaded
* @param win {Window} the targeted window
* @param qlength the number of remaining items in the queue,
* including this one
* @param trackfn {Function} function to execute when finished
* the default is _next
* @private
*/
_track = function(type, n, id, url, win, qlength, trackfn) {
var f = trackfn || _next, rs, q, a, freq, w, l, i, msg;
// IE supports the readystatechange event for script and css nodes
if (ua.ie) {
n.onreadystatechange = function() {
rs = this.readyState;
if ("loaded" === rs || "complete" === rs) {
n.onreadystatechange = null;
f(id, url);
}
};
// webkit prior to 3.x is problemmatic
} else if (ua.webkit) {
if (type === "script") {
// Safari 3.x supports the load event for script nodes (DOM2)
if (ua.webkit >= 420) {
n.addEventListener("load", function() {
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.
q = queues[id];
if (q.varName) {
freq = YAHOO.util.Get.POLL_FREQ;
q.maxattempts = YAHOO.util.Get.TIMEOUT/freq;
q.attempts = 0;
q._cache = q.varName[0].split(".");
q.timer = lang.later(freq, q, function(o) {
a = this._cache;
l = a.length;
w = this.win;
for (i=0; i this.maxattempts) {
msg = "Over retry limit, giving up";
q.timer.cancel();
_fail(id, msg);
} else {
}
return;
}
}
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() {
f(id, url);
};
}
};
/*
* 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
*/
_fail = function(id, msg) {
var q = queues[id], context;
// execute failure callback
if (q.onFailure) {
context = q.scope || q.win;
q.onFailure.call(context, _returnData(q, msg));
}
};
/**
* Removes the nodes for the specified queue
* @method _purge
* @private
*/
_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
* 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) {
* 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) {
* },
* 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",
*
* @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: "2.9.0", build: "2800"});