get.js revision 9e9c3dbe96011180df555dd8c27780404dddc855
L=Y.Lang;
/*
* Provides a mechanism to fetch remote resources and
* insert them into a document
* @module get
*/
/**
* Fetches and inserts one or more script or link nodes into the document
* @class Get
* @static
*/
Y.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;
/**
* 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
*/
for (var i in attr) {
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 c = charset || "utf-8";
return _node("link", {
"charset": c,
"rel": "stylesheet",
"href": url
}, 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 c = charset || "utf-8";
return _node("script", {
"type": "text/javascript",
"charset": c,
"src": url
}, win);
};
/**
* Returns the data payload for callback functions
* @method _returnData
* @private
*/
var _returnData = function(q, msg) {
return {
purge: function() {
}
};
};
if (!n) {
}
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
*/
// execute failure callback
if (q.onFailure) {
}
};
/**
* The request is complete, so executing the requester's callback
* @method _finish
* @param id {string} the id of the request
* @private
*/
q.finished = true;
if (q.aborted) {
return;
}
// execute success callback
if (q.onSuccess) {
}
};
/**
* Timeout detected
* @method _timeout
* @param id {string} the id of the request
* @private
*/
if (q.onTimeout) {
}
};
/**
* 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
*/
if (q.timer) {
}
if (q.aborted) {
return;
}
if (loaded) {
if (q.varName) {
}
} else {
// This is the first pass: make sure the url is an array
if (q.varName) {
}
}
return;
}
if (q.timeout) {
}
if (q.type === "script") {
} else {
}
// track this node's load progress
// add the node to the queue so we can return it to the user supplied callback
// add it to the head or insert it before 'insertBefore'
if (q.insertBefore) {
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.
}
};
/**
* 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];
delete queues[i];
}
}
purging = false;
};
/**
* Removes the nodes for the specified queue
* @method _purge
* @private
*/
if (q) {
if (q.insertBefore) {
if (s) {
h = s.parentNode;
}
}
for (var i=0; i<l; i=i+1) {
h.removeChild(n[i]);
}
}
q.nodes = [];
};
/**
* 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
*/
_autoPurge();
}
finished: false,
nodes: []
});
(type === "script") ? true : false;
return {
};
};
/**
* 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
*/
// IE supports the readystatechange event for script and css nodes
n.onreadystatechange = function() {
var rs = this.readyState;
}
};
// webkit prior to 3.x is no longer supported
if (type === "script") {
// Safari 3.x supports the load event for script nodes (DOM2)
n.addEventListener("load", function() {
});
}
// 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() {
};
}
};
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
*/
},
/**
* Abort a transaction
* @method abort
* @param {string|object} either the tId or the object returned from
* script() or css()
*/
abort: function(o) {
if (q) {
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:
* <dl>
* <dt>onSuccess</dt>
* <dd>
* callback to execute when the script(s) are finished loading
* The callback receives an object back with the following
* data:
* <dl>
* <dt>win</dt>
* <dd>the window the script(s) were inserted into</dd>
* <dt>data</dt>
* <dd>the data object passed in when the request was made</dd>
* <dt>nodes</dt>
* <dd>An array containing references to the nodes that were
* inserted</dd>
* <dt>purge</dt>
* <dd>A function that, when executed, will remove the nodes
* that were inserted</dd>
* <dt>
* </dl>
* </dd>
* <dt>onFailure</dt>
* <dd>
* callback to execute when the script load operation fails
* The callback receives an object back with the following
* data:
* <dl>
* <dt>win</dt>
* <dd>the window the script(s) were inserted into</dd>
* <dt>data</dt>
* <dd>the data object passed in when the request was made</dd>
* <dt>nodes</dt>
* <dd>An array containing references to the nodes that were
* inserted successfully</dd>
* <dt>purge</dt>
* <dd>A function that, when executed, will remove any nodes
* that were inserted</dd>
* <dt>
* </dl>
* </dd>
* <dt>scope</dt>
* <dd>the execution context for the callbacks</dd>
* <dt>win</dt>
* <dd>a window other than the one the utility occupies</dd>
* <dt>autopurge</dt>
* <dd>
* setting to true will let the utilities cleanup routine purge
* the script once loaded
* </dd>
* <dt>data</dt>
* <dd>
* data that is supplied to the callback when the script(s) are
* loaded.
* </dd>
* <dt>varName</dt>
* <dd>
* 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.
* </dd>
* <dt>insertBefore</dt>
* <dd>node or node id that will become the new node's nextSibling</dd>
* </dl>
* <dt>charset</dt>
* <dd>Node charset, default utf-8</dd>
* <pre>
* // assumes yahoo, dom, and event are already on the page
* Y.Get.script(
* ["http://yui.yahooapis.com/2.3.1/build/dragdrop/dragdrop-min.js",
* "http://yui.yahooapis.com/2.3.1/build/animation/animation-min.js"], {
* onSuccess: function(o) {
* console.log(o.data); // foo
* new Y.DDProxy("dd1"); // also new o.reference("dd1"); would work
* },
* onFailure: function(o) {
* console.log("transaction failed");
* },
* data: "foo",
* scope: Y,
* autopurge: true // allow the utility to choose when to remove the nodes
* });
* </pre>
* @return {tId: string} an object containing info about the transaction
*/
},
/**
* 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:
* <dl>
* <dt>onSuccess</dt>
* <dd>
* callback to execute when the css file(s) are finished loading
* The callback receives an object back with the following
* data:
* <dl>win</dl>
* <dd>the window the link nodes(s) were inserted into</dd>
* <dt>data</dt>
* <dd>the data object passed in when the request was made</dd>
* <dt>nodes</dt>
* <dd>An array containing references to the nodes that were
* inserted</dd>
* <dt>purge</dt>
* <dd>A function that, when executed, will remove the nodes
* that were inserted</dd>
* <dt>
* </dl>
* </dd>
* <dt>scope</dt>
* <dd>the execution context for the callbacks</dd>
* <dt>win</dt>
* <dd>a window other than the one the utility occupies</dd>
* <dt>data</dt>
* <dd>
* data that is supplied to the callbacks when the nodes(s) are
* loaded.
* </dd>
* <dt>insertBefore</dt>
* <dd>node or node id that will become the new node's nextSibling</dd>
* <dt>charset</dt>
* <dd>Node charset, default utf-8</dd>
* </dl>
* <pre>
* </pre>
* <pre>
* </pre>
* @return {tId: string} an object containing info about the transaction
*/
}
};
}();
}, "@VERSION@");