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if(!dojo._hasResource["dojo.io.script"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojo.io.script"] = true;
dojo.provide("dojo.io.script");
/*=====
dojo.io.script.__ioArgs = function(kwArgs){
// summary:
// All the properties described in the dojo.__ioArgs type, apply to this
// type as well, EXCEPT "handleAs". It is not applicable to
// dojo.io.script.get() calls, since it is implied by the usage of
// "callbackParamName" (response will be a JSONP call returning JSON)
// or "checkString" (response is pure JavaScript defined in
// the body of the script that was attached). The following additional
// properties are allowed for dojo.io.script.get():
// callbackParamName: String
// The URL parameter name that indicates the JSONP callback string.
// For instance, when using Yahoo JSONP calls it is normally,
// callbackParamName: "callback". For AOL JSONP calls it is normally
// callbackParamName: "c".
// checkString: String
// A string of JavaScript that when evaluated like so:
// "typeof(" + checkString + ") != 'undefined'"
// being true means that the script fetched has been loaded.
// Do not use this if doing a JSONP type of call (use callbackParamName instead).
// frameDoc: Document.
// The Document object for a child iframe. If this is passed in, the script
// will be attached to that document. This can be helpful in some comet long-polling
// scenarios with Firefox and Opera.
}
=====*/
dojo.io.script = {
get: function(/*dojo.io.script.__ioArgs*/args){
// summary:
// sends a get request using a dynamically created script tag.
var dfd = this._makeScriptDeferred(args);
var ioArgs = dfd.ioArgs;
dojo._ioAddQueryToUrl(ioArgs);
this.attach(ioArgs.id, ioArgs.url, args.frameDoc);
dojo._ioWatch(dfd, this._validCheck, this._ioCheck, this._resHandle);
return dfd;
},
attach: function(/*String*/id, /*String*/url, /*Document?*/frameDocument){
// summary:
// creates a new <script> tag pointing to the specified URL and
// adds it to the document.
// description:
// Attaches the script element to the DOM. Use this method if you
// just want to attach a script to the DOM and do not care when or
// if it loads.
var doc = (frameDocument || dojo.doc);
var element = doc.createElement("script");
element.type = "text/javascript";
element.src = url;
element.id = id;
doc.getElementsByTagName("head")[0].appendChild(element);
},
remove: function(/*String*/id){
//summary: removes the script element with the given id.
dojo._destroyElement(dojo.byId(id));
//Remove the jsonp callback on dojo.io.script, if it exists.
if(this["jsonp_" + id]){
delete this["jsonp_" + id];
}
},
_makeScriptDeferred: function(/*Object*/args){
//summary:
// sets up a Deferred object for an IO request.
var dfd = dojo._ioSetArgs(args, this._deferredCancel, this._deferredOk, this._deferredError);
var ioArgs = dfd.ioArgs;
ioArgs.id = dojo._scopeName + "IoScript" + (this._counter++);
ioArgs.canDelete = false;
//Special setup for jsonp case
if(args.callbackParamName){
//Add the jsonp parameter.
ioArgs.query = ioArgs.query || "";
if(ioArgs.query.length > 0){
ioArgs.query += "&";
}
ioArgs.query += args.callbackParamName
+ "="
+ (args.frameDoc ? "parent." : "")
+ "dojo.io.script.jsonp_" + ioArgs.id + "._jsonpCallback";
//Setup the Deferred to have the jsonp callback.
ioArgs.canDelete = true;
dfd._jsonpCallback = this._jsonpCallback;
this["jsonp_" + ioArgs.id] = dfd;
}
return dfd; // dojo.Deferred
},
_deferredCancel: function(/*Deferred*/dfd){
//summary: canceller function for dojo._ioSetArgs call.
//DO NOT use "this" and expect it to be dojo.io.script.
dfd.canceled = true;
if(dfd.ioArgs.canDelete){
dojo.io.script._deadScripts.push(dfd.ioArgs.id);
}
},
_deferredOk: function(/*Deferred*/dfd){
//summary: okHandler function for dojo._ioSetArgs call.
//DO NOT use "this" and expect it to be dojo.io.script.
//Add script to list of things that can be removed.
if(dfd.ioArgs.canDelete){
dojo.io.script._deadScripts.push(dfd.ioArgs.id);
}
if(dfd.ioArgs.json){
//Make sure to *not* remove the json property from the
//Deferred, so that the Deferred can still function correctly
//after the response is received.
return dfd.ioArgs.json;
}else{
//FIXME: cannot return the dfd here, otherwise that stops
//the callback chain in Deferred. So return the ioArgs instead.
//This doesn't feel right.
return dfd.ioArgs;
}
},
_deferredError: function(/*Error*/error, /*Deferred*/dfd){
//summary: errHandler function for dojo._ioSetArgs call.
if(dfd.ioArgs.canDelete){
//DO NOT use "this" and expect it to be dojo.io.script.
if(error.dojoType == "timeout"){
//For timeouts, remove the script element immediately to
//avoid a response from it coming back later and causing trouble.
dojo.io.script.remove(dfd.ioArgs.id);
}else{
dojo.io.script._deadScripts.push(dfd.ioArgs.id);
}
}
console.debug("dojo.io.script error", error);
return error;
},
_deadScripts: [],
_counter: 1,
_validCheck: function(/*Deferred*/dfd){
//summary: inflight check function to see if dfd is still valid.
//Do script cleanup here. We wait for one inflight pass
//to make sure we don't get any weird things by trying to remove a script
//tag that is part of the call chain (IE 6 has been known to
//crash in that case).
var _self = dojo.io.script;
var deadScripts = _self._deadScripts;
if(deadScripts && deadScripts.length > 0){
for(var i = 0; i < deadScripts.length; i++){
//Remove the script tag
_self.remove(deadScripts[i]);
}
dojo.io.script._deadScripts = [];
}
return true;
},
_ioCheck: function(/*Deferred*/dfd){
//summary: inflight check function to see if IO finished.
//Check for finished jsonp
if(dfd.ioArgs.json){
return true;
}
//Check for finished "checkString" case.
var checkString = dfd.ioArgs.args.checkString;
if(checkString && eval("typeof(" + checkString + ") != 'undefined'")){
return true;
}
return false;
},
_resHandle: function(/*Deferred*/dfd){
//summary: inflight function to handle a completed response.
if(dojo.io.script._ioCheck(dfd)){
dfd.callback(dfd);
}else{
//This path should never happen since the only way we can get
//to _resHandle is if _ioCheck is true.
dfd.errback(new Error("inconceivable dojo.io.script._resHandle error"));
}
},
_jsonpCallback: function(/*JSON Object*/json){
//summary:
// generic handler for jsonp callback. A pointer to this function
// is used for all jsonp callbacks. NOTE: the "this" in this
// function will be the Deferred object that represents the script
// request.
this.ioArgs.json = json;
}
}
}
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