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1 /*
2 Copyright (c) 2009, Yahoo! Inc. All rights reserved.
3 Code licensed under the BSD License:
4 http://developer.yahoo.net/yui/license.txt
5 version: 2.8.0r4
6 */
7 /**
8  * The Connection Manager provides a simplified interface to the XMLHttpRequest
9  * object.  It handles cross-browser instantiantion of XMLHttpRequest, negotiates the
10  * interactive states and server response, returning the results to a pre-defined
11  * callback you create.
12  *
13  * @namespace YAHOO.util
14  * @module connection
15  * @requires yahoo
16  * @requires event
17  */
18
19 /**
20  * The Connection Manager singleton provides methods for creating and managing
21  * asynchronous transactions.
22  *
23  * @class Connect
24  */
25
26 YAHOO.util.Connect =
27 {
28   /**
29    * @description Array of MSFT ActiveX ids for XMLHttpRequest.
30    * @property _msxml_progid
31    * @private
32    * @static
33    * @type array
34    */
35         _msxml_progid:[
36                 'Microsoft.XMLHTTP',
37                 'MSXML2.XMLHTTP.3.0',
38                 'MSXML2.XMLHTTP'
39                 ],
40
41   /**
42    * @description Object literal of HTTP header(s)
43    * @property _http_header
44    * @private
45    * @static
46    * @type object
47    */
48         _http_headers:{},
49
50   /**
51    * @description Determines if HTTP headers are set.
52    * @property _has_http_headers
53    * @private
54    * @static
55    * @type boolean
56    */
57         _has_http_headers:false,
58
59  /**
60   * @description Determines if a default header of
61   * Content-Type of 'application/x-www-form-urlencoded'
62   * will be added to any client HTTP headers sent for POST
63   * transactions.
64   * @property _use_default_post_header
65   * @private
66   * @static
67   * @type boolean
68   */
69     _use_default_post_header:true,
70
71  /**
72   * @description The default header used for POST transactions.
73   * @property _default_post_header
74   * @private
75   * @static
76   * @type boolean
77   */
78     _default_post_header:'application/x-www-form-urlencoded; charset=UTF-8',
79
80  /**
81   * @description The default header used for transactions involving the
82   * use of HTML forms.
83   * @property _default_form_header
84   * @private
85   * @static
86   * @type boolean
87   */
88     _default_form_header:'application/x-www-form-urlencoded',
89
90  /**
91   * @description Determines if a default header of
92   * 'X-Requested-With: XMLHttpRequest'
93   * will be added to each transaction.
94   * @property _use_default_xhr_header
95   * @private
96   * @static
97   * @type boolean
98   */
99     _use_default_xhr_header:true,
100
101  /**
102   * @description The default header value for the label
103   * "X-Requested-With".  This is sent with each
104   * transaction, by default, to identify the
105   * request as being made by YUI Connection Manager.
106   * @property _default_xhr_header
107   * @private
108   * @static
109   * @type boolean
110   */
111     _default_xhr_header:'XMLHttpRequest',
112
113  /**
114   * @description Determines if custom, default headers
115   * are set for each transaction.
116   * @property _has_default_header
117   * @private
118   * @static
119   * @type boolean
120   */
121     _has_default_headers:true,
122
123  /**
124   * @description Determines if custom, default headers
125   * are set for each transaction.
126   * @property _has_default_header
127   * @private
128   * @static
129   * @type boolean
130   */
131     _default_headers:{},
132
133  /**
134   * @description Collection of polling references to the polling mechanism in handleReadyState.
135   * @property _poll
136   * @private
137   * @static
138   * @type object
139   */
140     _poll:{},
141
142  /**
143   * @description Queue of timeout values for each transaction callback with a defined timeout value.
144   * @property _timeOut
145   * @private
146   * @static
147   * @type object
148   */
149     _timeOut:{},
150
151   /**
152    * @description The polling frequency, in milliseconds, for HandleReadyState.
153    * when attempting to determine a transaction's XHR readyState.
154    * The default is 50 milliseconds.
155    * @property _polling_interval
156    * @private
157    * @static
158    * @type int
159    */
160      _polling_interval:50,
161
162   /**
163    * @description A transaction counter that increments the transaction id for each transaction.
164    * @property _transaction_id
165    * @private
166    * @static
167    * @type int
168    */
169      _transaction_id:0,
170
171   /**
172    * @description Custom event that fires at the start of a transaction
173    * @property startEvent
174    * @private
175    * @static
176    * @type CustomEvent
177    */
178         startEvent: new YAHOO.util.CustomEvent('start'),
179
180   /**
181    * @description Custom event that fires when a transaction response has completed.
182    * @property completeEvent
183    * @private
184    * @static
185    * @type CustomEvent
186    */
187         completeEvent: new YAHOO.util.CustomEvent('complete'),
188
189   /**
190    * @description Custom event that fires when handleTransactionResponse() determines a
191    * response in the HTTP 2xx range.
192    * @property successEvent
193    * @private
194    * @static
195    * @type CustomEvent
196    */
197         successEvent: new YAHOO.util.CustomEvent('success'),
198
199   /**
200    * @description Custom event that fires when handleTransactionResponse() determines a
201    * response in the HTTP 4xx/5xx range.
202    * @property failureEvent
203    * @private
204    * @static
205    * @type CustomEvent
206    */
207         failureEvent: new YAHOO.util.CustomEvent('failure'),
208
209   /**
210    * @description Custom event that fires when a transaction is successfully aborted.
211    * @property abortEvent
212    * @private
213    * @static
214    * @type CustomEvent
215    */
216         abortEvent: new YAHOO.util.CustomEvent('abort'),
217
218   /**
219    * @description A reference table that maps callback custom events members to its specific
220    * event name.
221    * @property _customEvents
222    * @private
223    * @static
224    * @type object
225    */
226         _customEvents:
227         {
228                 onStart:['startEvent', 'start'],
229                 onComplete:['completeEvent', 'complete'],
230                 onSuccess:['successEvent', 'success'],
231                 onFailure:['failureEvent', 'failure'],
232                 onUpload:['uploadEvent', 'upload'],
233                 onAbort:['abortEvent', 'abort']
234         },
235
236   /**
237    * @description Member to add an ActiveX id to the existing xml_progid array.
238    * In the event(unlikely) a new ActiveX id is introduced, it can be added
239    * without internal code modifications.
240    * @method setProgId
241    * @public
242    * @static
243    * @param {string} id The ActiveX id to be added to initialize the XHR object.
244    * @return void
245    */
246         setProgId:function(id)
247         {
248                 this._msxml_progid.unshift(id);
249         },
250
251   /**
252    * @description Member to override the default POST header.
253    * @method setDefaultPostHeader
254    * @public
255    * @static
256    * @param {boolean} b Set and use default header - true or false .
257    * @return void
258    */
259         setDefaultPostHeader:function(b)
260         {
261                 if(typeof b == 'string'){
262                         this._default_post_header = b;
263                 }
264                 else if(typeof b == 'boolean'){
265                         this._use_default_post_header = b;
266                 }
267         },
268
269   /**
270    * @description Member to override the default transaction header..
271    * @method setDefaultXhrHeader
272    * @public
273    * @static
274    * @param {boolean} b Set and use default header - true or false .
275    * @return void
276    */
277         setDefaultXhrHeader:function(b)
278         {
279                 if(typeof b == 'string'){
280                         this._default_xhr_header = b;
281                 }
282                 else{
283                         this._use_default_xhr_header = b;
284                 }
285         },
286
287   /**
288    * @description Member to modify the default polling interval.
289    * @method setPollingInterval
290    * @public
291    * @static
292    * @param {int} i The polling interval in milliseconds.
293    * @return void
294    */
295         setPollingInterval:function(i)
296         {
297                 if(typeof i == 'number' && isFinite(i)){
298                         this._polling_interval = i;
299                 }
300         },
301
302   /**
303    * @description Instantiates a XMLHttpRequest object and returns an object with two properties:
304    * the XMLHttpRequest instance and the transaction id.
305    * @method createXhrObject
306    * @private
307    * @static
308    * @param {int} transactionId Property containing the transaction id for this transaction.
309    * @return object
310    */
311         createXhrObject:function(transactionId)
312         {
313                 var obj,http,i;
314                 try
315                 {
316                         // Instantiates XMLHttpRequest in non-IE browsers and assigns to http.
317                         http = new XMLHttpRequest();
318                         //  Object literal with http and tId properties
319                         obj = { conn:http, tId:transactionId, xhr: true };
320                 }
321                 catch(e)
322                 {
323                         for(i=0; i<this._msxml_progid.length; ++i){
324                                 try
325                                 {
326                                         // Instantiates XMLHttpRequest for IE and assign to http
327                                         http = new ActiveXObject(this._msxml_progid[i]);
328                                         //  Object literal with conn and tId properties
329                                         obj = { conn:http, tId:transactionId, xhr: true };
330                                         break;
331                                 }
332                                 catch(e1){}
333                         }
334                 }
335                 finally
336                 {
337                         return obj;
338                 }
339         },
340
341   /**
342    * @description This method is called by asyncRequest to create a
343    * valid connection object for the transaction.  It also passes a
344    * transaction id and increments the transaction id counter.
345    * @method getConnectionObject
346    * @private
347    * @static
348    * @return {object}
349    */
350         getConnectionObject:function(t)
351         {
352                 var o, tId = this._transaction_id;
353
354                 try
355                 {
356                         if(!t){
357                                 o = this.createXhrObject(tId);
358                         }
359                         else{
360                                 o = {tId:tId};
361                                 if(t==='xdr'){
362                                         o.conn = this._transport;
363                                         o.xdr = true;
364                                 }
365                                 else if(t==='upload'){
366                                         o.upload = true;
367                                 }
368                         }
369
370                         if(o){
371                                 this._transaction_id++;
372                         }
373                 }
374                 catch(e){}
375                 return o;
376         },
377
378   /**
379    * @description Method for initiating an asynchronous request via the XHR object.
380    * @method asyncRequest
381    * @public
382    * @static
383    * @param {string} method HTTP transaction method
384    * @param {string} uri Fully qualified path of resource
385    * @param {callback} callback User-defined callback function or object
386    * @param {string} postData POST body
387    * @return {object} Returns the connection object
388    */
389         asyncRequest:function(method, uri, callback, postData)
390         {
391                 var o,t,args = (callback && callback.argument)?callback.argument:null;
392
393                 if(this._isFileUpload){
394                         t = 'upload';
395                 }
396                 else if(callback.xdr){
397                         t = 'xdr';
398                 }
399
400                 o = this.getConnectionObject(t);
401                 if(!o){
402                         return null;
403                 }
404                 else{
405
406                         // Intialize any transaction-specific custom events, if provided.
407                         if(callback && callback.customevents){
408                                 this.initCustomEvents(o, callback);
409                         }
410
411                         if(this._isFormSubmit){
412                                 if(this._isFileUpload){
413                                         this.uploadFile(o, callback, uri, postData);
414                                         return o;
415                                 }
416
417                                 // If the specified HTTP method is GET, setForm() will return an
418                                 // encoded string that is concatenated to the uri to
419                                 // create a querystring.
420                                 if(method.toUpperCase() == 'GET'){
421                                         if(this._sFormData.length !== 0){
422                                                 // If the URI already contains a querystring, append an ampersand
423                                                 // and then concatenate _sFormData to the URI.
424                                                 uri += ((uri.indexOf('?') == -1)?'?':'&') + this._sFormData;
425                                         }
426                                 }
427                                 else if(method.toUpperCase() == 'POST'){
428                                         // If POST data exist in addition to the HTML form data,
429                                         // it will be concatenated to the form data.
430                                         postData = postData?this._sFormData + "&" + postData:this._sFormData;
431                                 }
432                         }
433
434                         if(method.toUpperCase() == 'GET' && (callback && callback.cache === false)){
435                                 // If callback.cache is defined and set to false, a
436                                 // timestamp value will be added to the querystring.
437                                 uri += ((uri.indexOf('?') == -1)?'?':'&') + "rnd=" + new Date().valueOf().toString();
438                         }
439
440                         // Each transaction will automatically include a custom header of
441                         // "X-Requested-With: XMLHttpRequest" to identify the request as
442                         // having originated from Connection Manager.
443                         if(this._use_default_xhr_header){
444                                 if(!this._default_headers['X-Requested-With']){
445                                         this.initHeader('X-Requested-With', this._default_xhr_header, true);
446                                 }
447                         }
448
449                         //If the transaction method is POST and the POST header value is set to true
450                         //or a custom value, initalize the Content-Type header to this value.
451                         if((method.toUpperCase() === 'POST' && this._use_default_post_header) && this._isFormSubmit === false){
452                                 this.initHeader('Content-Type', this._default_post_header);
453                         }
454
455                         if(o.xdr){
456                                 this.xdr(o, method, uri, callback, postData);
457                                 return o;
458                         }
459
460                         o.conn.open(method, uri, true);
461                         //Initialize all default and custom HTTP headers,
462                         if(this._has_default_headers || this._has_http_headers){
463                                 this.setHeader(o);
464                         }
465
466                         this.handleReadyState(o, callback);
467                         o.conn.send(postData || '');
468
469                         // Reset the HTML form data and state properties as
470                         // soon as the data are submitted.
471                         if(this._isFormSubmit === true){
472                                 this.resetFormState();
473                         }
474
475                         // Fire global custom event -- startEvent
476                         this.startEvent.fire(o, args);
477
478                         if(o.startEvent){
479                                 // Fire transaction custom event -- startEvent
480                                 o.startEvent.fire(o, args);
481                         }
482
483                         return o;
484                 }
485         },
486
487   /**
488    * @description This method creates and subscribes custom events,
489    * specific to each transaction
490    * @method initCustomEvents
491    * @private
492    * @static
493    * @param {object} o The connection object
494    * @param {callback} callback The user-defined callback object
495    * @return {void}
496    */
497         initCustomEvents:function(o, callback)
498         {
499                 var prop;
500                 // Enumerate through callback.customevents members and bind/subscribe
501                 // events that match in the _customEvents table.
502                 for(prop in callback.customevents){
503                         if(this._customEvents[prop][0]){
504                                 // Create the custom event
505                                 o[this._customEvents[prop][0]] = new YAHOO.util.CustomEvent(this._customEvents[prop][1], (callback.scope)?callback.scope:null);
506
507                                 // Subscribe the custom event
508                                 o[this._customEvents[prop][0]].subscribe(callback.customevents[prop]);
509                         }
510                 }
511         },
512
513   /**
514    * @description This method serves as a timer that polls the XHR object's readyState
515    * property during a transaction, instead of binding a callback to the
516    * onreadystatechange event.  Upon readyState 4, handleTransactionResponse
517    * will process the response, and the timer will be cleared.
518    * @method handleReadyState
519    * @private
520    * @static
521    * @param {object} o The connection object
522    * @param {callback} callback The user-defined callback object
523    * @return {void}
524    */
525
526     handleReadyState:function(o, callback)
527
528     {
529                 var oConn = this,
530                         args = (callback && callback.argument)?callback.argument:null;
531
532                 if(callback && callback.timeout){
533                         this._timeOut[o.tId] = window.setTimeout(function(){ oConn.abort(o, callback, true); }, callback.timeout);
534                 }
535
536                 this._poll[o.tId] = window.setInterval(
537                         function(){
538                                 if(o.conn && o.conn.readyState === 4){
539
540                                         // Clear the polling interval for the transaction
541                                         // and remove the reference from _poll.
542                                         window.clearInterval(oConn._poll[o.tId]);
543                                         delete oConn._poll[o.tId];
544
545                                         if(callback && callback.timeout){
546                                                 window.clearTimeout(oConn._timeOut[o.tId]);
547                                                 delete oConn._timeOut[o.tId];
548                                         }
549
550                                         // Fire global custom event -- completeEvent
551                                         oConn.completeEvent.fire(o, args);
552
553                                         if(o.completeEvent){
554                                                 // Fire transaction custom event -- completeEvent
555                                                 o.completeEvent.fire(o, args);
556                                         }
557
558                                         oConn.handleTransactionResponse(o, callback);
559                                 }
560                         }
561                 ,this._polling_interval);
562     },
563
564   /**
565    * @description This method attempts to interpret the server response and
566    * determine whether the transaction was successful, or if an error or
567    * exception was encountered.
568    * @method handleTransactionResponse
569    * @private
570    * @static
571    * @param {object} o The connection object
572    * @param {object} callback The user-defined callback object
573    * @param {boolean} isAbort Determines if the transaction was terminated via abort().
574    * @return {void}
575    */
576     handleTransactionResponse:function(o, callback, isAbort)
577     {
578                 var httpStatus, responseObject,
579                         args = (callback && callback.argument)?callback.argument:null,
580                         xdrS = (o.r && o.r.statusText === 'xdr:success')?true:false,
581                         xdrF = (o.r && o.r.statusText === 'xdr:failure')?true:false,
582                         xdrA = isAbort;
583
584                 try
585                 {
586                         if((o.conn.status !== undefined && o.conn.status !== 0) || xdrS){
587                                 // XDR requests will not have HTTP status defined. The
588                                 // statusText property will define the response status
589                                 // set by the Flash transport.
590                                 httpStatus = o.conn.status;
591                         }
592                         else if(xdrF && !xdrA){
593                                 // Set XDR transaction failure to a status of 0, which
594                                 // resolves as an HTTP failure, instead of an exception.
595                                 httpStatus = 0;
596                         }
597                         else{
598                                 httpStatus = 13030;
599                         }
600                 }
601                 catch(e){
602
603                          // 13030 is a custom code to indicate the condition -- in Mozilla/FF --
604                          // when the XHR object's status and statusText properties are
605                          // unavailable, and a query attempt throws an exception.
606                         httpStatus = 13030;
607                 }
608
609                 if((httpStatus >= 200 && httpStatus < 300) || httpStatus === 1223 || xdrS){
610                         responseObject = o.xdr ? o.r : this.createResponseObject(o, args);
611                         if(callback && callback.success){
612                                 if(!callback.scope){
613                                         callback.success(responseObject);
614                                 }
615                                 else{
616                                         // If a scope property is defined, the callback will be fired from
617                                         // the context of the object.
618                                         callback.success.apply(callback.scope, [responseObject]);
619                                 }
620                         }
621
622                         // Fire global custom event -- successEvent
623                         this.successEvent.fire(responseObject);
624
625                         if(o.successEvent){
626                                 // Fire transaction custom event -- successEvent
627                                 o.successEvent.fire(responseObject);
628                         }
629                 }
630                 else{
631                         switch(httpStatus){
632                                 // The following cases are wininet.dll error codes that may be encountered.
633                                 case 12002: // Server timeout
634                                 case 12029: // 12029 to 12031 correspond to dropped connections.
635                                 case 12030:
636                                 case 12031:
637                                 case 12152: // Connection closed by server.
638                                 case 13030: // See above comments for variable status.
639                                         // XDR transactions will not resolve to this case, since the
640                                         // response object is already built in the xdr response.
641                                         responseObject = this.createExceptionObject(o.tId, args, (isAbort?isAbort:false));
642                                         if(callback && callback.failure){
643                                                 if(!callback.scope){
644                                                         callback.failure(responseObject);
645                                                 }
646                                                 else{
647                                                         callback.failure.apply(callback.scope, [responseObject]);
648                                                 }
649                                         }
650
651                                         break;
652                                 default:
653                                         responseObject = (o.xdr) ? o.response : this.createResponseObject(o, args);
654                                         if(callback && callback.failure){
655                                                 if(!callback.scope){
656                                                         callback.failure(responseObject);
657                                                 }
658                                                 else{
659                                                         callback.failure.apply(callback.scope, [responseObject]);
660                                                 }
661                                         }
662                         }
663
664                         // Fire global custom event -- failureEvent
665                         this.failureEvent.fire(responseObject);
666
667                         if(o.failureEvent){
668                                 // Fire transaction custom event -- failureEvent
669                                 o.failureEvent.fire(responseObject);
670                         }
671
672                 }
673
674                 this.releaseObject(o);
675                 responseObject = null;
676     },
677
678   /**
679    * @description This method evaluates the server response, creates and returns the results via
680    * its properties.  Success and failure cases will differ in the response
681    * object's property values.
682    * @method createResponseObject
683    * @private
684    * @static
685    * @param {object} o The connection object
686    * @param {callbackArg} callbackArg The user-defined argument or arguments to be passed to the callback
687    * @return {object}
688    */
689     createResponseObject:function(o, callbackArg)
690     {
691                 var obj = {}, headerObj = {},
692                         i, headerStr, header, delimitPos;
693
694                 try
695                 {
696                         headerStr = o.conn.getAllResponseHeaders();
697                         header = headerStr.split('\n');
698                         for(i=0; i<header.length; i++){
699                                 delimitPos = header[i].indexOf(':');
700                                 if(delimitPos != -1){
701                                         headerObj[header[i].substring(0,delimitPos)] = YAHOO.lang.trim(header[i].substring(delimitPos+2));
702                                 }
703                         }
704                 }
705                 catch(e){}
706
707                 obj.tId = o.tId;
708                 // Normalize IE's response to HTTP 204 when Win error 1223.
709                 obj.status = (o.conn.status == 1223)?204:o.conn.status;
710                 // Normalize IE's statusText to "No Content" instead of "Unknown".
711                 obj.statusText = (o.conn.status == 1223)?"No Content":o.conn.statusText;
712                 obj.getResponseHeader = headerObj;
713                 obj.getAllResponseHeaders = headerStr;
714                 obj.responseText = o.conn.responseText;
715                 obj.responseXML = o.conn.responseXML;
716
717                 if(callbackArg){
718                         obj.argument = callbackArg;
719                 }
720
721                 return obj;
722     },
723
724   /**
725    * @description If a transaction cannot be completed due to dropped or closed connections,
726    * there may be not be enough information to build a full response object.
727    * The failure callback will be fired and this specific condition can be identified
728    * by a status property value of 0.
729    *
730    * If an abort was successful, the status property will report a value of -1.
731    *
732    * @method createExceptionObject
733    * @private
734    * @static
735    * @param {int} tId The Transaction Id
736    * @param {callbackArg} callbackArg The user-defined argument or arguments to be passed to the callback
737    * @param {boolean} isAbort Determines if the exception case is caused by a transaction abort
738    * @return {object}
739    */
740     createExceptionObject:function(tId, callbackArg, isAbort)
741     {
742                 var COMM_CODE = 0,
743                         COMM_ERROR = 'communication failure',
744                         ABORT_CODE = -1,
745                         ABORT_ERROR = 'transaction aborted',
746                         obj = {};
747
748                 obj.tId = tId;
749                 if(isAbort){
750                         obj.status = ABORT_CODE;
751                         obj.statusText = ABORT_ERROR;
752                 }
753                 else{
754                         obj.status = COMM_CODE;
755                         obj.statusText = COMM_ERROR;
756                 }
757
758                 if(callbackArg){
759                         obj.argument = callbackArg;
760                 }
761
762                 return obj;
763     },
764
765   /**
766    * @description Method that initializes the custom HTTP headers for the each transaction.
767    * @method initHeader
768    * @public
769    * @static
770    * @param {string} label The HTTP header label
771    * @param {string} value The HTTP header value
772    * @param {string} isDefault Determines if the specific header is a default header
773    * automatically sent with each transaction.
774    * @return {void}
775    */
776         initHeader:function(label, value, isDefault)
777         {
778                 var headerObj = (isDefault)?this._default_headers:this._http_headers;
779
780                 headerObj[label] = value;
781                 if(isDefault){
782                         this._has_default_headers = true;
783                 }
784                 else{
785                         this._has_http_headers = true;
786                 }
787         },
788
789
790   /**
791    * @description Accessor that sets the HTTP headers for each transaction.
792    * @method setHeader
793    * @private
794    * @static
795    * @param {object} o The connection object for the transaction.
796    * @return {void}
797    */
798         setHeader:function(o)
799         {
800                 var prop;
801                 if(this._has_default_headers){
802                         for(prop in this._default_headers){
803                                 if(YAHOO.lang.hasOwnProperty(this._default_headers, prop)){
804                                         o.conn.setRequestHeader(prop, this._default_headers[prop]);
805                                 }
806                         }
807                 }
808
809                 if(this._has_http_headers){
810                         for(prop in this._http_headers){
811                                 if(YAHOO.lang.hasOwnProperty(this._http_headers, prop)){
812                                         o.conn.setRequestHeader(prop, this._http_headers[prop]);
813                                 }
814                         }
815
816                         this._http_headers = {};
817                         this._has_http_headers = false;
818                 }
819         },
820
821   /**
822    * @description Resets the default HTTP headers object
823    * @method resetDefaultHeaders
824    * @public
825    * @static
826    * @return {void}
827    */
828         resetDefaultHeaders:function(){
829                 this._default_headers = {};
830                 this._has_default_headers = false;
831         },
832
833   /**
834    * @description Method to terminate a transaction, if it has not reached readyState 4.
835    * @method abort
836    * @public
837    * @static
838    * @param {object} o The connection object returned by asyncRequest.
839    * @param {object} callback  User-defined callback object.
840    * @param {string} isTimeout boolean to indicate if abort resulted from a callback timeout.
841    * @return {boolean}
842    */
843         abort:function(o, callback, isTimeout)
844         {
845                 var abortStatus,
846                         args = (callback && callback.argument)?callback.argument:null;
847                         o = o || {};
848
849                 if(o.conn){
850                         if(o.xhr){
851                                 if(this.isCallInProgress(o)){
852                                         // Issue abort request
853                                         o.conn.abort();
854
855                                         window.clearInterval(this._poll[o.tId]);
856                                         delete this._poll[o.tId];
857
858                                         if(isTimeout){
859                                                 window.clearTimeout(this._timeOut[o.tId]);
860                                                 delete this._timeOut[o.tId];
861                                         }
862
863                                         abortStatus = true;
864                                 }
865                         }
866                         else if(o.xdr){
867                                 o.conn.abort(o.tId);
868                                 abortStatus = true;
869                         }
870                 }
871                 else if(o.upload){
872                         var frameId = 'yuiIO' + o.tId;
873                         var io = document.getElementById(frameId);
874
875                         if(io){
876                                 // Remove all listeners on the iframe prior to
877                                 // its destruction.
878                                 YAHOO.util.Event.removeListener(io, "load");
879                                 // Destroy the iframe facilitating the transaction.
880                                 document.body.removeChild(io);
881
882                                 if(isTimeout){
883                                         window.clearTimeout(this._timeOut[o.tId]);
884                                         delete this._timeOut[o.tId];
885                                 }
886
887                                 abortStatus = true;
888                         }
889                 }
890                 else{
891                         abortStatus = false;
892                 }
893
894                 if(abortStatus === true){
895                         // Fire global custom event -- abortEvent
896                         this.abortEvent.fire(o, args);
897
898                         if(o.abortEvent){
899                                 // Fire transaction custom event -- abortEvent
900                                 o.abortEvent.fire(o, args);
901                         }
902
903                         this.handleTransactionResponse(o, callback, true);
904                 }
905
906                 return abortStatus;
907         },
908
909   /**
910    * @description Determines if the transaction is still being processed.
911    * @method isCallInProgress
912    * @public
913    * @static
914    * @param {object} o The connection object returned by asyncRequest
915    * @return {boolean}
916    */
917         isCallInProgress:function(o)
918         {
919                 o = o || {};
920                 // if the XHR object assigned to the transaction has not been dereferenced,
921                 // then check its readyState status.  Otherwise, return false.
922                 if(o.xhr && o.conn){
923                         return o.conn.readyState !== 4 && o.conn.readyState !== 0;
924                 }
925                 else if(o.xdr && o.conn){
926                         return o.conn.isCallInProgress(o.tId);
927                 }
928                 else if(o.upload === true){
929                         return document.getElementById('yuiIO' + o.tId)?true:false;
930                 }
931                 else{
932                         return false;
933                 }
934         },
935
936   /**
937    * @description Dereference the XHR instance and the connection object after the transaction is completed.
938    * @method releaseObject
939    * @private
940    * @static
941    * @param {object} o The connection object
942    * @return {void}
943    */
944         releaseObject:function(o)
945         {
946                 if(o && o.conn){
947                         //dereference the XHR instance.
948                         o.conn = null;
949
950
951                         //dereference the connection object.
952                         o = null;
953                 }
954         }
955 };
956
957 /**
958   * @for Connect
959   */
960 (function() {
961         var YCM = YAHOO.util.Connect, _fn = {};
962
963    /**
964     * @description This method creates and instantiates the Flash transport.
965     * @method _swf
966     * @private
967     * @static
968     * @param {string} URI to connection.swf.
969     * @return {void}
970     */
971         function _swf(uri) {
972                 var o = '<object id="YUIConnectionSwf" type="application/x-shockwave-flash" data="' +
973                         uri + '" width="0" height="0">' +
974                         '<param name="movie" value="' + uri + '">' +
975                 '<param name="allowScriptAccess" value="always">' +
976                         '</object>',
977                     c = document.createElement('div');
978
979                 document.body.appendChild(c);
980                 c.innerHTML = o;
981         }
982
983    /**
984     * @description This method calls the public method on the
985     * Flash transport to start the XDR transaction.  It is analogous
986     * to Connection Manager's asyncRequest method.
987     * @method xdr
988     * @private
989     * @static
990     * @param {object} The transaction object.
991     * @param {string} HTTP request method.
992     * @param {string} URI for the transaction.
993     * @param {object} The transaction's callback object.
994     * @param {object} The JSON object used as HTTP POST data.
995     * @return {void}
996     */
997         function _xdr(o, m, u, c, d) {
998                 _fn[parseInt(o.tId)] = { 'o':o, 'c':c };
999                 if (d) {
1000                         c.method = m;
1001                         c.data = d;
1002                 }
1003
1004                 o.conn.send(u, c, o.tId);
1005         }
1006
1007    /**
1008     * @description This method instantiates the Flash transport and
1009     * establishes a static reference to it, used for all XDR requests.
1010     * @method transport
1011     * @public
1012     * @static
1013     * @param {string} URI to connection.swf.
1014     * @return {void}
1015     */
1016         function _init(uri) {
1017                 _swf(uri);
1018                 YCM._transport = document.getElementById('YUIConnectionSwf');
1019         }
1020
1021         function _xdrReady() {
1022                 YCM.xdrReadyEvent.fire();
1023         }
1024
1025    /**
1026     * @description This method fires the global and transaction start
1027     * events.
1028     * @method _xdrStart
1029     * @private
1030     * @static
1031     * @param {object} The transaction object.
1032     * @param {string} The transaction's callback object.
1033     * @return {void}
1034     */
1035         function _xdrStart(o, cb) {
1036                 if (o) {
1037                         // Fire global custom event -- startEvent
1038                         YCM.startEvent.fire(o, cb.argument);
1039
1040                         if(o.startEvent){
1041                                 // Fire transaction custom event -- startEvent
1042                                 o.startEvent.fire(o, cb.argument);
1043                         }
1044                 }
1045         }
1046
1047    /**
1048     * @description This method is the initial response handler
1049     * for XDR transactions.  The Flash transport calls this
1050     * function and sends the response payload.
1051     * @method handleXdrResponse
1052     * @private
1053     * @static
1054     * @param {object} The response object sent from the Flash transport.
1055     * @return {void}
1056     */
1057         function _handleXdrResponse(r) {
1058                 var o = _fn[r.tId].o,
1059                         cb = _fn[r.tId].c;
1060
1061                 if (r.statusText === 'xdr:start') {
1062                         _xdrStart(o, cb);
1063                         return;
1064                 }
1065
1066                 r.responseText = decodeURI(r.responseText);
1067                 o.r = r;
1068                 if (cb.argument) {
1069                         o.r.argument = cb.argument;
1070                 }
1071
1072                 this.handleTransactionResponse(o, cb, r.statusText === 'xdr:abort' ? true : false);
1073                 delete _fn[r.tId];
1074         }
1075
1076         // Bind the functions to Connection Manager as static fields.
1077         YCM.xdr = _xdr;
1078         YCM.swf = _swf;
1079         YCM.transport = _init;
1080         YCM.xdrReadyEvent = new YAHOO.util.CustomEvent('xdrReady');
1081         YCM.xdrReady = _xdrReady;
1082         YCM.handleXdrResponse = _handleXdrResponse;
1083 })();
1084
1085 /**
1086   * @for Connect
1087   */
1088 (function(){
1089         var YCM = YAHOO.util.Connect,
1090                 YE = YAHOO.util.Event;
1091    /**
1092         * @description Property modified by setForm() to determine if the data
1093         * should be submitted as an HTML form.
1094         * @property _isFormSubmit
1095         * @private
1096         * @static
1097         * @type boolean
1098         */
1099         YCM._isFormSubmit = false;
1100
1101    /**
1102         * @description Property modified by setForm() to determine if a file(s)
1103         * upload is expected.
1104         * @property _isFileUpload
1105         * @private
1106         * @static
1107         * @type boolean
1108         */
1109         YCM._isFileUpload = false;
1110
1111    /**
1112         * @description Property modified by setForm() to set a reference to the HTML
1113         * form node if the desired action is file upload.
1114         * @property _formNode
1115         * @private
1116         * @static
1117         * @type object
1118         */
1119         YCM._formNode = null;
1120
1121    /**
1122         * @description Property modified by setForm() to set the HTML form data
1123         * for each transaction.
1124         * @property _sFormData
1125         * @private
1126         * @static
1127         * @type string
1128         */
1129         YCM._sFormData = null;
1130
1131    /**
1132         * @description Tracks the name-value pair of the "clicked" submit button if multiple submit
1133         * buttons are present in an HTML form; and, if YAHOO.util.Event is available.
1134         * @property _submitElementValue
1135         * @private
1136         * @static
1137         * @type string
1138         */
1139         YCM._submitElementValue = null;
1140
1141    /**
1142     * @description Custom event that fires when handleTransactionResponse() determines a
1143     * response in the HTTP 4xx/5xx range.
1144     * @property failureEvent
1145     * @private
1146     * @static
1147     * @type CustomEvent
1148     */
1149         YCM.uploadEvent = new YAHOO.util.CustomEvent('upload'),
1150
1151    /**
1152         * @description Determines whether YAHOO.util.Event is available and returns true or false.
1153         * If true, an event listener is bound at the document level to trap click events that
1154         * resolve to a target type of "Submit".  This listener will enable setForm() to determine
1155         * the clicked "Submit" value in a multi-Submit button, HTML form.
1156         * @property _hasSubmitListener
1157         * @private
1158         * @static
1159         */
1160         YCM._hasSubmitListener = function() {
1161                 if(YE){
1162                         YE.addListener(
1163                                 document,
1164                                 'click',
1165                                 function(e){
1166                                         var obj = YE.getTarget(e),
1167                                                 name = obj.nodeName.toLowerCase();
1168
1169                                         if((name === 'input' || name === 'button') && (obj.type && obj.type.toLowerCase() == 'submit')){
1170                                                 YCM._submitElementValue = encodeURIComponent(obj.name) + "=" + encodeURIComponent(obj.value);
1171                                         }
1172                                 });
1173                         return true;
1174                 }
1175                 return false;
1176         }();
1177
1178   /**
1179    * @description This method assembles the form label and value pairs and
1180    * constructs an encoded string.
1181    * asyncRequest() will automatically initialize the transaction with a
1182    * a HTTP header Content-Type of application/x-www-form-urlencoded.
1183    * @method setForm
1184    * @public
1185    * @static
1186    * @param {string || object} form id or name attribute, or form object.
1187    * @param {boolean} optional enable file upload.
1188    * @param {boolean} optional enable file upload over SSL in IE only.
1189    * @return {string} string of the HTML form field name and value pairs..
1190    */
1191         function _setForm(formId, isUpload, secureUri)
1192         {
1193                 var oForm, oElement, oName, oValue, oDisabled,
1194                         hasSubmit = false,
1195                         data = [], item = 0,
1196                         i,len,j,jlen,opt;
1197
1198                 this.resetFormState();
1199
1200                 if(typeof formId == 'string'){
1201                         // Determine if the argument is a form id or a form name.
1202                         // Note form name usage is deprecated by supported
1203                         // here for legacy reasons.
1204                         oForm = (document.getElementById(formId) || document.forms[formId]);
1205                 }
1206                 else if(typeof formId == 'object'){
1207                         // Treat argument as an HTML form object.
1208                         oForm = formId;
1209                 }
1210                 else{
1211                         return;
1212                 }
1213
1214                 // If the isUpload argument is true, setForm will call createFrame to initialize
1215                 // an iframe as the form target.
1216                 //
1217                 // The argument secureURI is also required by IE in SSL environments
1218                 // where the secureURI string is a fully qualified HTTP path, used to set the source
1219                 // of the iframe, to a stub resource in the same domain.
1220                 if(isUpload){
1221
1222                         // Create iframe in preparation for file upload.
1223                         this.createFrame(secureUri?secureUri:null);
1224
1225                         // Set form reference and file upload properties to true.
1226                         this._isFormSubmit = true;
1227                         this._isFileUpload = true;
1228                         this._formNode = oForm;
1229
1230                         return;
1231                 }
1232
1233                 // Iterate over the form elements collection to construct the
1234                 // label-value pairs.
1235                 for (i=0,len=oForm.elements.length; i<len; ++i){
1236                         oElement  = oForm.elements[i];
1237                         oDisabled = oElement.disabled;
1238                         oName     = oElement.name;
1239
1240                         // Do not submit fields that are disabled or
1241                         // do not have a name attribute value.
1242                         if(!oDisabled && oName)
1243                         {
1244                                 oName  = encodeURIComponent(oName)+'=';
1245                                 oValue = encodeURIComponent(oElement.value);
1246
1247                                 switch(oElement.type)
1248                                 {
1249                                         // Safari, Opera, FF all default opt.value from .text if
1250                                         // value attribute not specified in markup
1251                                         case 'select-one':
1252                                                 if (oElement.selectedIndex > -1) {
1253                                                         opt = oElement.options[oElement.selectedIndex];
1254                                                         data[item++] = oName + encodeURIComponent(
1255                                                                 (opt.attributes.value && opt.attributes.value.specified) ? opt.value : opt.text);
1256                                                 }
1257                                                 break;
1258                                         case 'select-multiple':
1259                                                 if (oElement.selectedIndex > -1) {
1260                                                         for(j=oElement.selectedIndex, jlen=oElement.options.length; j<jlen; ++j){
1261                                                                 opt = oElement.options[j];
1262                                                                 if (opt.selected) {
1263                                                                         data[item++] = oName + encodeURIComponent(
1264                                                                                 (opt.attributes.value && opt.attributes.value.specified) ? opt.value : opt.text);
1265                                                                 }
1266                                                         }
1267                                                 }
1268                                                 break;
1269                                         case 'radio':
1270                                         case 'checkbox':
1271                                                 if(oElement.checked){
1272                                                         data[item++] = oName + oValue;
1273                                                 }
1274                                                 break;
1275                                         case 'file':
1276                                                 // stub case as XMLHttpRequest will only send the file path as a string.
1277                                         case undefined:
1278                                                 // stub case for fieldset element which returns undefined.
1279                                         case 'reset':
1280                                                 // stub case for input type reset button.
1281                                         case 'button':
1282                                                 // stub case for input type button elements.
1283                                                 break;
1284                                         case 'submit':
1285                                                 if(hasSubmit === false){
1286                                                         if(this._hasSubmitListener && this._submitElementValue){
1287                                                                 data[item++] = this._submitElementValue;
1288                                                         }
1289                                                         hasSubmit = true;
1290                                                 }
1291                                                 break;
1292                                         default:
1293                                                 data[item++] = oName + oValue;
1294                                 }
1295                         }
1296                 }
1297
1298                 this._isFormSubmit = true;
1299                 this._sFormData = data.join('&');
1300
1301
1302                 this.initHeader('Content-Type', this._default_form_header);
1303
1304                 return this._sFormData;
1305         }
1306
1307    /**
1308     * @description Resets HTML form properties when an HTML form or HTML form
1309     * with file upload transaction is sent.
1310     * @method resetFormState
1311     * @private
1312     * @static
1313     * @return {void}
1314     */
1315         function _resetFormState(){
1316                 this._isFormSubmit = false;
1317                 this._isFileUpload = false;
1318                 this._formNode = null;
1319                 this._sFormData = "";
1320         }
1321
1322
1323    /**
1324     * @description Creates an iframe to be used for form file uploads.  It is remove from the
1325     * document upon completion of the upload transaction.
1326     * @method createFrame
1327     * @private
1328     * @static
1329     * @param {string} optional qualified path of iframe resource for SSL in IE.
1330     * @return {void}
1331     */
1332         function _createFrame(secureUri){
1333
1334                 // IE does not allow the setting of id and name attributes as object
1335                 // properties via createElement().  A different iframe creation
1336                 // pattern is required for IE.
1337                 var frameId = 'yuiIO' + this._transaction_id,
1338                         io;
1339                 if(YAHOO.env.ua.ie){
1340                         io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');
1341
1342                         // IE will throw a security exception in an SSL environment if the
1343                         // iframe source is undefined.
1344                         if(typeof secureUri == 'boolean'){
1345                                 io.src = 'javascript:false';
1346                         }
1347                 }
1348                 else{
1349                         io = document.createElement('iframe');
1350                         io.id = frameId;
1351                         io.name = frameId;
1352                 }
1353
1354                 io.style.position = 'absolute';
1355                 io.style.top = '-1000px';
1356                 io.style.left = '-1000px';
1357
1358                 document.body.appendChild(io);
1359         }
1360
1361    /**
1362     * @description Parses the POST data and creates hidden form elements
1363     * for each key-value, and appends them to the HTML form object.
1364     * @method appendPostData
1365     * @private
1366     * @static
1367     * @param {string} postData The HTTP POST data
1368     * @return {array} formElements Collection of hidden fields.
1369     */
1370         function _appendPostData(postData){
1371                 var formElements = [],
1372                         postMessage = postData.split('&'),
1373                         i, delimitPos;
1374
1375                 for(i=0; i < postMessage.length; i++){
1376                         delimitPos = postMessage[i].indexOf('=');
1377                         if(delimitPos != -1){
1378                                 formElements[i] = document.createElement('input');
1379                                 formElements[i].type = 'hidden';
1380                                 formElements[i].name = decodeURIComponent(postMessage[i].substring(0,delimitPos));
1381                                 formElements[i].value = decodeURIComponent(postMessage[i].substring(delimitPos+1));
1382                                 this._formNode.appendChild(formElements[i]);
1383                         }
1384                 }
1385
1386                 return formElements;
1387         }
1388
1389    /**
1390     * @description Uploads HTML form, inclusive of files/attachments, using the
1391     * iframe created in createFrame to facilitate the transaction.
1392     * @method uploadFile
1393     * @private
1394     * @static
1395     * @param {int} id The transaction id.
1396     * @param {object} callback User-defined callback object.
1397     * @param {string} uri Fully qualified path of resource.
1398     * @param {string} postData POST data to be submitted in addition to HTML form.
1399     * @return {void}
1400     */
1401         function _uploadFile(o, callback, uri, postData){
1402                 // Each iframe has an id prefix of "yuiIO" followed
1403                 // by the unique transaction id.
1404                 var frameId = 'yuiIO' + o.tId,
1405                     uploadEncoding = 'multipart/form-data',
1406                     io = document.getElementById(frameId),
1407                     ie8 = (document.documentMode && document.documentMode === 8) ? true : false,
1408                     oConn = this,
1409                         args = (callback && callback.argument)?callback.argument:null,
1410             oElements,i,prop,obj, rawFormAttributes, uploadCallback;
1411
1412                 // Track original HTML form attribute values.
1413                 rawFormAttributes = {
1414                         action:this._formNode.getAttribute('action'),
1415                         method:this._formNode.getAttribute('method'),
1416                         target:this._formNode.getAttribute('target')
1417                 };
1418
1419                 // Initialize the HTML form properties in case they are
1420                 // not defined in the HTML form.
1421                 this._formNode.setAttribute('action', uri);
1422                 this._formNode.setAttribute('method', 'POST');
1423                 this._formNode.setAttribute('target', frameId);
1424
1425                 if(YAHOO.env.ua.ie && !ie8){
1426                         // IE does not respect property enctype for HTML forms.
1427                         // Instead it uses the property - "encoding".
1428                         this._formNode.setAttribute('encoding', uploadEncoding);
1429                 }
1430                 else{
1431                         this._formNode.setAttribute('enctype', uploadEncoding);
1432                 }
1433
1434                 if(postData){
1435                         oElements = this.appendPostData(postData);
1436                 }
1437
1438                 // Start file upload.
1439                 this._formNode.submit();
1440
1441                 // Fire global custom event -- startEvent
1442                 this.startEvent.fire(o, args);
1443
1444                 if(o.startEvent){
1445                         // Fire transaction custom event -- startEvent
1446                         o.startEvent.fire(o, args);
1447                 }
1448
1449                 // Start polling if a callback is present and the timeout
1450                 // property has been defined.
1451                 if(callback && callback.timeout){
1452                         this._timeOut[o.tId] = window.setTimeout(function(){ oConn.abort(o, callback, true); }, callback.timeout);
1453                 }
1454
1455                 // Remove HTML elements created by appendPostData
1456                 if(oElements && oElements.length > 0){
1457                         for(i=0; i < oElements.length; i++){
1458                                 this._formNode.removeChild(oElements[i]);
1459                         }
1460                 }
1461
1462                 // Restore HTML form attributes to their original
1463                 // values prior to file upload.
1464                 for(prop in rawFormAttributes){
1465                         if(YAHOO.lang.hasOwnProperty(rawFormAttributes, prop)){
1466                                 if(rawFormAttributes[prop]){
1467                                         this._formNode.setAttribute(prop, rawFormAttributes[prop]);
1468                                 }
1469                                 else{
1470                                         this._formNode.removeAttribute(prop);
1471                                 }
1472                         }
1473                 }
1474
1475                 // Reset HTML form state properties.
1476                 this.resetFormState();
1477
1478                 // Create the upload callback handler that fires when the iframe
1479                 // receives the load event.  Subsequently, the event handler is detached
1480                 // and the iframe removed from the document.
1481                 uploadCallback = function() {
1482                         if(callback && callback.timeout){
1483                                 window.clearTimeout(oConn._timeOut[o.tId]);
1484                                 delete oConn._timeOut[o.tId];
1485                         }
1486
1487                         // Fire global custom event -- completeEvent
1488                         oConn.completeEvent.fire(o, args);
1489
1490                         if(o.completeEvent){
1491                                 // Fire transaction custom event -- completeEvent
1492                                 o.completeEvent.fire(o, args);
1493                         }
1494
1495                         obj = {
1496                             tId : o.tId,
1497                             argument : callback.argument
1498             };
1499
1500                         try
1501                         {
1502                                 // responseText and responseXML will be populated with the same data from the iframe.
1503                                 // Since the HTTP headers cannot be read from the iframe
1504                                 obj.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:io.contentWindow.document.documentElement.textContent;
1505                                 obj.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;
1506                         }
1507                         catch(e){}
1508
1509                         if(callback && callback.upload){
1510                                 if(!callback.scope){
1511                                         callback.upload(obj);
1512                                 }
1513                                 else{
1514                                         callback.upload.apply(callback.scope, [obj]);
1515                                 }
1516                         }
1517
1518                         // Fire global custom event -- uploadEvent
1519                         oConn.uploadEvent.fire(obj);
1520
1521                         if(o.uploadEvent){
1522                                 // Fire transaction custom event -- uploadEvent
1523                                 o.uploadEvent.fire(obj);
1524                         }
1525
1526                         YE.removeListener(io, "load", uploadCallback);
1527
1528                         setTimeout(
1529                                 function(){
1530                                         document.body.removeChild(io);
1531                                         oConn.releaseObject(o);
1532                                 }, 100);
1533                 };
1534
1535                 // Bind the onload handler to the iframe to detect the file upload response.
1536                 YE.addListener(io, "load", uploadCallback);
1537         }
1538
1539         YCM.setForm = _setForm;
1540         YCM.resetFormState = _resetFormState;
1541         YCM.createFrame = _createFrame;
1542         YCM.appendPostData = _appendPostData;
1543         YCM.uploadFile = _uploadFile;
1544 })();
1545
1546 YAHOO.register("connection", YAHOO.util.Connect, {version: "2.8.0r4", build: "2449"});