tt-rss/lib/dojo/io/script.js
2011-11-08 20:40:44 +04:00

262 lines
8.6 KiB
JavaScript

/*
Copyright (c) 2004-2011, The Dojo Foundation All Rights Reserved.
Available via Academic Free License >= 2.1 OR the modified BSD license.
see: http://dojotoolkit.org/license for details
*/
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.getObject("io", true, dojo);
/*=====
dojo.declare("dojo.io.script.__ioArgs", dojo.__IoArgs, {
constructor: function(){
// 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
// "jsonp" (response will be a JSONP call returning JSON)
// or the response is pure JavaScript defined in
// the body of the script that was attached.
// callbackParamName: String
// Deprecated as of Dojo 1.4 in favor of "jsonp", but still supported for
// legacy code. See notes for jsonp property.
// jsonp: String
// The URL parameter name that indicates the JSONP callback string.
// For instance, when using Yahoo JSONP calls it is normally,
// jsonp: "callback". For AOL JSONP calls it is normally
// jsonp: "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.
this.callbackParamName = callbackParamName;
this.jsonp = jsonp;
this.checkString = checkString;
this.frameDoc = frameDoc;
}
});
=====*/
(function(){
var loadEvent = dojo.isIE ? "onreadystatechange" : "load",
readyRegExp = /complete|loaded/;
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);
dojo._ioNotifyStart(dfd);
if(this._canAttach(ioArgs)){
var node = this.attach(ioArgs.id, ioArgs.url, args.frameDoc);
//If not a jsonp callback or a polling checkString case, bind
//to load event on the script tag.
if(!ioArgs.jsonp && !ioArgs.args.checkString){
var handle = dojo.connect(node, loadEvent, function(evt){
if(evt.type == "load" || readyRegExp.test(node.readyState)){
dojo.disconnect(handle);
ioArgs.scriptLoaded = evt;
}
});
}
}
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;
element.charset = "utf-8";
return doc.getElementsByTagName("head")[0].appendChild(element);
},
remove: function(/*String*/id, /*Document?*/frameDocument){
//summary: removes the script element with the given id, from the given frameDocument.
//If no frameDocument is passed, the current document is used.
dojo.destroy(dojo.byId(id, frameDocument));
//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
ioArgs.jsonp = args.callbackParamName || args.jsonp;
if(ioArgs.jsonp){
//Add the jsonp parameter.
ioArgs.query = ioArgs.query || "";
if(ioArgs.query.length > 0){
ioArgs.query += "&";
}
ioArgs.query += ioArgs.jsonp
+ "="
+ (args.frameDoc ? "parent." : "")
+ dojo._scopeName + ".io.script.jsonp_" + ioArgs.id + "._jsonpCallback";
ioArgs.frameDoc = args.frameDoc;
//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._addDeadScript(dfd.ioArgs);
}
},
_deferredOk: function(/*Deferred*/dfd){
//summary: okHandler function for dojo._ioSetArgs call.
//DO NOT use "this" and expect it to be dojo.io.script.
var ioArgs = dfd.ioArgs;
//Add script to list of things that can be removed.
if(ioArgs.canDelete){
dojo.io.script._addDeadScript(ioArgs);
}
//Favor JSONP responses, script load events then lastly ioArgs.
//The ioArgs are goofy, but cannot return the dfd since that stops
//the callback chain in Deferred. The return value is not that important
//in that case, probably a checkString case.
return ioArgs.json || ioArgs.scriptLoaded || 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, dfd.ioArgs.frameDoc);
}else{
dojo.io.script._addDeadScript(dfd.ioArgs);
}
}
console.log("dojo.io.script error", error);
return error;
},
_deadScripts: [],
_counter: 1,
_addDeadScript: function(/*Object*/ioArgs){
//summary: sets up an entry in the deadScripts array.
dojo.io.script._deadScripts.push({id: ioArgs.id, frameDoc: ioArgs.frameDoc});
//Being extra paranoid about leaks:
ioArgs.frameDoc = null;
},
_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].id, deadScripts[i].frameDoc);
deadScripts[i].frameDoc = null;
}
dojo.io.script._deadScripts = [];
}
return true;
},
_ioCheck: function(/*Deferred*/dfd){
//summary: inflight check function to see if IO finished.
var ioArgs = dfd.ioArgs;
//Check for finished jsonp
if(ioArgs.json || (ioArgs.scriptLoaded && !ioArgs.args.checkString)){
return true;
}
//Check for finished "checkString" case.
var checkString = 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"));
}
},
_canAttach: function(/*Object*/ioArgs){
//summary: A method that can be overridden by other modules
//to control when the script attachment occurs.
return true;
},
_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;
}
};
})();
}