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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
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 * @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
        YAHOO.log('ActiveX Program Id  ' + id + ' added to _msxml_progid.', 'info', 'Connection');
250
    },
251

    
252
  /**
253
  * @description Member to override the default POST header.
254
  * @method setDefaultPostHeader
255
  * @public
256
  * @static
257
  * @param {boolean} b Set and use default header - true or false .
258
  * @return void
259
   */
260
    setDefaultPostHeader:function(b)
261
    {
262
        if(typeof b == 'string'){
263
            this._default_post_header = b;
264
            YAHOO.log('Default POST header set to  ' + b, 'info', 'Connection');
265
        }
266
        else if(typeof b == 'boolean'){
267
            this._use_default_post_header = b;
268
        }
269
    },
270

    
271
  /**
272
  * @description Member to override the default transaction header..
273
  * @method setDefaultXhrHeader
274
  * @public
275
  * @static
276
  * @param {boolean} b Set and use default header - true or false .
277
  * @return void
278
   */
279
    setDefaultXhrHeader:function(b)
280
    {
281
        if(typeof b == 'string'){
282
            this._default_xhr_header = b;
283
            YAHOO.log('Default XHR header set to  ' + b, 'info', 'Connection');
284
        }
285
        else{
286
            this._use_default_xhr_header = b;
287
        }
288
    },
289

    
290
  /**
291
  * @description Member to modify the default polling interval.
292
  * @method setPollingInterval
293
  * @public
294
  * @static
295
  * @param {int} i The polling interval in milliseconds.
296
  * @return void
297
   */
298
    setPollingInterval:function(i)
299
    {
300
        if(typeof i == 'number' && isFinite(i)){
301
            this._polling_interval = i;
302
            YAHOO.log('Default polling interval set to ' + i +'ms', 'info', 'Connection');
303
        }
304
    },
305

    
306
  /**
307
  * @description Instantiates a XMLHttpRequest object and returns an object with two properties:
308
   * the XMLHttpRequest instance and the transaction id.
309
  * @method createXhrObject
310
  * @private
311
  * @static
312
  * @param {int} transactionId Property containing the transaction id for this transaction.
313
  * @return object
314
   */
315
    createXhrObject:function(transactionId)
316
    {
317
        var obj,http,i;
318
        try
319
        {
320
            // Instantiates XMLHttpRequest in non-IE browsers and assigns to http.
321
            http = new XMLHttpRequest();
322
            //  Object literal with http and tId properties
323
            obj = { conn:http, tId:transactionId, xhr: true };
324
            YAHOO.log('XHR object created for transaction ' + transactionId, 'info', 'Connection');
325
        }
326
        catch(e)
327
        {
328
            for(i=0; i<this._msxml_progid.length; ++i){
329
                try
330
                {
331
                    // Instantiates XMLHttpRequest for IE and assign to http
332
                    http = new ActiveXObject(this._msxml_progid[i]);
333
                    //  Object literal with conn and tId properties
334
                    obj = { conn:http, tId:transactionId, xhr: true };
335
                    YAHOO.log('ActiveX XHR object created for transaction ' + transactionId, 'info', 'Connection');
336
                    break;
337
                }
338
                catch(e1){}
339
            }
340
        }
341
        finally
342
        {
343
            return obj;
344
        }
345
    },
346

    
347
  /**
348
  * @description This method is called by asyncRequest to create a
349
   * valid connection object for the transaction.  It also passes a
350
   * transaction id and increments the transaction id counter.
351
  * @method getConnectionObject
352
  * @private
353
  * @static
354
  * @return {object}
355
   */
356
    getConnectionObject:function(t)
357
    {
358
        var o, tId = this._transaction_id;
359

    
360
        try
361
        {
362
            if(!t){
363
                o = this.createXhrObject(tId);
364
            }
365
            else{
366
                o = {tId:tId};
367
                if(t==='xdr'){
368
                    o.conn = this._transport;
369
                    o.xdr = true;
370
                }
371
                else if(t==='upload'){
372
                    o.upload = true;
373
                }
374
            }
375

    
376
            if(o){
377
                this._transaction_id++;
378
            }
379
        }
380
        catch(e){}
381
        return o;
382
    },
383

    
384
  /**
385
  * @description Method for initiating an asynchronous request via the XHR object.
386
  * @method asyncRequest
387
  * @public
388
  * @static
389
  * @param {string} method HTTP transaction method
390
  * @param {string} uri Fully qualified path of resource
391
  * @param {callback} callback User-defined callback function or object
392
  * @param {string} postData POST body
393
  * @return {object} Returns the connection object
394
   */
395
    asyncRequest:function(method, uri, callback, postData)
396
    {
397
        var o,t,args = (callback && callback.argument)?callback.argument:null;
398

    
399
        if(this._isFileUpload){
400
            t = 'upload';
401
        }
402
        else if(callback.xdr){
403
            t = 'xdr';
404
        }
405

    
406
        o = this.getConnectionObject(t);
407
        if(!o){
408
            YAHOO.log('Unable to create connection object.', 'error', 'Connection');
409
            return null;
410
        }
411
        else{
412

    
413
            // Intialize any transaction-specific custom events, if provided.
414
            if(callback && callback.customevents){
415
                this.initCustomEvents(o, callback);
416
            }
417

    
418
            if(this._isFormSubmit){
419
                if(this._isFileUpload){
420
                    this.uploadFile(o, callback, uri, postData);
421
                    return o;
422
                }
423

    
424
                // If the specified HTTP method is GET, setForm() will return an
425
                // encoded string that is concatenated to the uri to
426
                // create a querystring.
427
                if(method.toUpperCase() == 'GET'){
428
                    if(this._sFormData.length !== 0){
429
                        // If the URI already contains a querystring, append an ampersand
430
                        // and then concatenate _sFormData to the URI.
431
                        uri += ((uri.indexOf('?') == -1)?'?':'&') + this._sFormData;
432
                    }
433
                }
434
                else if(method.toUpperCase() == 'POST'){
435
                    // If POST data exist in addition to the HTML form data,
436
                    // it will be concatenated to the form data.
437
                    postData = postData?this._sFormData + "&" + postData:this._sFormData;
438
                }
439
            }
440

    
441
            if(method.toUpperCase() == 'GET' && (callback && callback.cache === false)){
442
                // If callback.cache is defined and set to false, a
443
                // timestamp value will be added to the querystring.
444
                uri += ((uri.indexOf('?') == -1)?'?':'&') + "rnd=" + new Date().valueOf().toString();
445
            }
446

    
447
            // Each transaction will automatically include a custom header of
448
            // "X-Requested-With: XMLHttpRequest" to identify the request as
449
            // having originated from Connection Manager.
450
            if(this._use_default_xhr_header){
451
                if(!this._default_headers['X-Requested-With']){
452
                    this.initHeader('X-Requested-With', this._default_xhr_header, true);
453
                    YAHOO.log('Initialize transaction header X-Request-Header to XMLHttpRequest.', 'info', 'Connection');
454
                }
455
            }
456

    
457
            //If the transaction method is POST and the POST header value is set to true
458
            //or a custom value, initalize the Content-Type header to this value.
459
            if((method.toUpperCase() === 'POST' && this._use_default_post_header) && this._isFormSubmit === false){
460
                this.initHeader('Content-Type', this._default_post_header);
461
                YAHOO.log('Initialize header Content-Type to application/x-www-form-urlencoded; UTF-8 for POST transaction.', 'info', 'Connection');
462
            }
463

    
464
            if(o.xdr){
465
                this.xdr(o, method, uri, callback, postData);
466
                return o;
467
            }
468

    
469
            o.conn.open(method, uri, true);
470
            //Initialize all default and custom HTTP headers,
471
            if(this._has_default_headers || this._has_http_headers){
472
                this.setHeader(o);
473
            }
474

    
475
            this.handleReadyState(o, callback);
476
            o.conn.send(postData || '');
477
            YAHOO.log('Transaction ' + o.tId + ' sent.', 'info', 'Connection');
478

    
479
            // Reset the HTML form data and state properties as
480
            // soon as the data are submitted.
481
            if(this._isFormSubmit === true){
482
                this.resetFormState();
483
            }
484

    
485
            // Fire global custom event -- startEvent
486
            this.startEvent.fire(o, args);
487

    
488
            if(o.startEvent){
489
                // Fire transaction custom event -- startEvent
490
                o.startEvent.fire(o, args);
491
            }
492

    
493
            return o;
494
        }
495
    },
496

    
497
  /**
498
  * @description This method creates and subscribes custom events,
499
   * specific to each transaction
500
  * @method initCustomEvents
501
  * @private
502
  * @static
503
  * @param {object} o The connection object
504
  * @param {callback} callback The user-defined callback object
505
  * @return {void}
506
   */
507
    initCustomEvents:function(o, callback)
508
    {
509
        var prop;
510
        // Enumerate through callback.customevents members and bind/subscribe
511
        // events that match in the _customEvents table.
512
        for(prop in callback.customevents){
513
            if(this._customEvents[prop][0]){
514
                // Create the custom event
515
                o[this._customEvents[prop][0]] = new YAHOO.util.CustomEvent(this._customEvents[prop][1], (callback.scope)?callback.scope:null);
516
                YAHOO.log('Transaction-specific Custom Event ' + o[this._customEvents[prop][1]] + ' created.', 'info', 'Connection');
517

    
518
                // Subscribe the custom event
519
                o[this._customEvents[prop][0]].subscribe(callback.customevents[prop]);
520
                YAHOO.log('Transaction-specific Custom Event ' + o[this._customEvents[prop][1]] + ' subscribed.', 'info', 'Connection');
521
            }
522
        }
523
    },
524

    
525
  /**
526
  * @description This method serves as a timer that polls the XHR object's readyState
527
   * property during a transaction, instead of binding a callback to the
528
   * onreadystatechange event.  Upon readyState 4, handleTransactionResponse
529
   * will process the response, and the timer will be cleared.
530
  * @method handleReadyState
531
  * @private
532
  * @static
533
  * @param {object} o The connection object
534
  * @param {callback} callback The user-defined callback object
535
  * @return {void}
536
   */
537

    
538
    handleReadyState:function(o, callback)
539

    
540
    {
541
        var oConn = this,
542
            args = (callback && callback.argument)?callback.argument:null;
543

    
544
        if(callback && callback.timeout){
545
            this._timeOut[o.tId] = window.setTimeout(function(){ oConn.abort(o, callback, true); }, callback.timeout);
546
        }
547

    
548
        this._poll[o.tId] = window.setInterval(
549
            function(){
550
                if(o.conn && o.conn.readyState === 4){
551

    
552
                    // Clear the polling interval for the transaction
553
                    // and remove the reference from _poll.
554
                    window.clearInterval(oConn._poll[o.tId]);
555
                    delete oConn._poll[o.tId];
556

    
557
                    if(callback && callback.timeout){
558
                        window.clearTimeout(oConn._timeOut[o.tId]);
559
                        delete oConn._timeOut[o.tId];
560
                    }
561

    
562
                    // Fire global custom event -- completeEvent
563
                    oConn.completeEvent.fire(o, args);
564

    
565
                    if(o.completeEvent){
566
                        // Fire transaction custom event -- completeEvent
567
                        o.completeEvent.fire(o, args);
568
                    }
569

    
570
                    oConn.handleTransactionResponse(o, callback);
571
                }
572
            }
573
        ,this._polling_interval);
574
    },
575

    
576
  /**
577
  * @description This method attempts to interpret the server response and
578
   * determine whether the transaction was successful, or if an error or
579
   * exception was encountered.
580
  * @method handleTransactionResponse
581
  * @private
582
  * @static
583
  * @param {object} o The connection object
584
  * @param {object} callback The user-defined callback object
585
  * @param {boolean} isAbort Determines if the transaction was terminated via abort().
586
  * @return {void}
587
   */
588
    handleTransactionResponse:function(o, callback, isAbort)
589
    {
590
        var httpStatus, responseObject,
591
            args = (callback && callback.argument)?callback.argument:null,
592
            xdrS = (o.r && o.r.statusText === 'xdr:success')?true:false,
593
            xdrF = (o.r && o.r.statusText === 'xdr:failure')?true:false,
594
            xdrA = isAbort;
595

    
596
        try
597
        {
598
            if((o.conn.status !== undefined && o.conn.status !== 0) || xdrS){
599
                // XDR requests will not have HTTP status defined. The
600
                // statusText property will define the response status
601
                // set by the Flash transport.
602
                httpStatus = o.conn.status;
603
            }
604
            else if(xdrF && !xdrA){
605
                // Set XDR transaction failure to a status of 0, which
606
                // resolves as an HTTP failure, instead of an exception.
607
                httpStatus = 0;
608
            }
609
            else{
610
                httpStatus = 13030;
611
            }
612
        }
613
        catch(e){
614

    
615
             // 13030 is a custom code to indicate the condition -- in Mozilla/FF --
616
             // when the XHR object's status and statusText properties are
617
             // unavailable, and a query attempt throws an exception.
618
            httpStatus = 13030;
619
        }
620

    
621
        if((httpStatus >= 200 && httpStatus < 300) || httpStatus === 1223 || xdrS){
622
            responseObject = o.xdr ? o.r : this.createResponseObject(o, args);
623
            if(callback && callback.success){
624
                if(!callback.scope){
625
                    callback.success(responseObject);
626
                    YAHOO.log('Success callback. HTTP code is ' + httpStatus, 'info', 'Connection');
627
                }
628
                else{
629
                    // If a scope property is defined, the callback will be fired from
630
                    // the context of the object.
631
                    callback.success.apply(callback.scope, [responseObject]);
632
                    YAHOO.log('Success callback with scope. HTTP code is ' + httpStatus, 'info', 'Connection');
633
                }
634
            }
635

    
636
            // Fire global custom event -- successEvent
637
            this.successEvent.fire(responseObject);
638

    
639
            if(o.successEvent){
640
                // Fire transaction custom event -- successEvent
641
                o.successEvent.fire(responseObject);
642
            }
643
        }
644
        else{
645
            switch(httpStatus){
646
                // The following cases are wininet.dll error codes that may be encountered.
647
                case 12002: // Server timeout
648
                case 12029: // 12029 to 12031 correspond to dropped connections.
649
                case 12030:
650
                case 12031:
651
                case 12152: // Connection closed by server.
652
                case 13030: // See above comments for variable status.
653
                    // XDR transactions will not resolve to this case, since the
654
                    // response object is already built in the xdr response.
655
                    responseObject = this.createExceptionObject(o.tId, args, (isAbort?isAbort:false));
656
                    if(callback && callback.failure){
657
                        if(!callback.scope){
658
                            callback.failure(responseObject);
659
                            YAHOO.log('Failure callback. Exception detected. Status code is ' + httpStatus, 'warn', 'Connection');
660
                        }
661
                        else{
662
                            callback.failure.apply(callback.scope, [responseObject]);
663
                            YAHOO.log('Failure callback with scope. Exception detected. Status code is ' + httpStatus, 'warn', 'Connection');
664
                        }
665
                    }
666

    
667
                    break;
668
                default:
669
                    responseObject = (o.xdr) ? o.response : this.createResponseObject(o, args);
670
                    if(callback && callback.failure){
671
                        if(!callback.scope){
672
                            callback.failure(responseObject);
673
                            YAHOO.log('Failure callback. HTTP status code is ' + httpStatus, 'warn', 'Connection');
674
                        }
675
                        else{
676
                            callback.failure.apply(callback.scope, [responseObject]);
677
                            YAHOO.log('Failure callback with scope. HTTP status code is ' + httpStatus, 'warn', 'Connection');
678
                        }
679
                    }
680
            }
681

    
682
            // Fire global custom event -- failureEvent
683
            this.failureEvent.fire(responseObject);
684

    
685
            if(o.failureEvent){
686
                // Fire transaction custom event -- failureEvent
687
                o.failureEvent.fire(responseObject);
688
            }
689

    
690
        }
691

    
692
        this.releaseObject(o);
693
        responseObject = null;
694
    },
695

    
696
  /**
697
  * @description This method evaluates the server response, creates and returns the results via
698
   * its properties.  Success and failure cases will differ in the response
699
   * object's property values.
700
  * @method createResponseObject
701
  * @private
702
  * @static
703
  * @param {object} o The connection object
704
  * @param {callbackArg} callbackArg The user-defined argument or arguments to be passed to the callback
705
  * @return {object}
706
   */
707
    createResponseObject:function(o, callbackArg)
708
    {
709
        var obj = {}, headerObj = {},
710
            i, headerStr, header, delimitPos;
711

    
712
        try
713
        {
714
            headerStr = o.conn.getAllResponseHeaders();
715
            header = headerStr.split('\n');
716
            for(i=0; i<header.length; i++){
717
                delimitPos = header[i].indexOf(':');
718
                if(delimitPos != -1){
719
                    headerObj[header[i].substring(0,delimitPos)] = YAHOO.lang.trim(header[i].substring(delimitPos+2));
720
                }
721
            }
722
        }
723
        catch(e){}
724

    
725
        obj.tId = o.tId;
726
        // Normalize IE's response to HTTP 204 when Win error 1223.
727
        obj.status = (o.conn.status == 1223)?204:o.conn.status;
728
        // Normalize IE's statusText to "No Content" instead of "Unknown".
729
        obj.statusText = (o.conn.status == 1223)?"No Content":o.conn.statusText;
730
        obj.getResponseHeader = headerObj;
731
        obj.getAllResponseHeaders = headerStr;
732
        obj.responseText = o.conn.responseText;
733
        obj.responseXML = o.conn.responseXML;
734

    
735
        if(callbackArg){
736
            obj.argument = callbackArg;
737
        }
738

    
739
        return obj;
740
    },
741

    
742
  /**
743
  * @description If a transaction cannot be completed due to dropped or closed connections,
744
   * there may be not be enough information to build a full response object.
745
   * The failure callback will be fired and this specific condition can be identified
746
   * by a status property value of 0.
747
   *
748
   * If an abort was successful, the status property will report a value of -1.
749
   *
750
  * @method createExceptionObject
751
  * @private
752
  * @static
753
  * @param {int} tId The Transaction Id
754
  * @param {callbackArg} callbackArg The user-defined argument or arguments to be passed to the callback
755
  * @param {boolean} isAbort Determines if the exception case is caused by a transaction abort
756
  * @return {object}
757
   */
758
    createExceptionObject:function(tId, callbackArg, isAbort)
759
    {
760
        var COMM_CODE = 0,
761
            COMM_ERROR = 'communication failure',
762
            ABORT_CODE = -1,
763
            ABORT_ERROR = 'transaction aborted',
764
            obj = {};
765

    
766
        obj.tId = tId;
767
        if(isAbort){
768
            obj.status = ABORT_CODE;
769
            obj.statusText = ABORT_ERROR;
770
        }
771
        else{
772
            obj.status = COMM_CODE;
773
            obj.statusText = COMM_ERROR;
774
        }
775

    
776
        if(callbackArg){
777
            obj.argument = callbackArg;
778
        }
779

    
780
        return obj;
781
    },
782

    
783
  /**
784
  * @description Method that initializes the custom HTTP headers for the each transaction.
785
  * @method initHeader
786
  * @public
787
  * @static
788
  * @param {string} label The HTTP header label
789
  * @param {string} value The HTTP header value
790
  * @param {string} isDefault Determines if the specific header is a default header
791
   * automatically sent with each transaction.
792
  * @return {void}
793
   */
794
    initHeader:function(label, value, isDefault)
795
    {
796
        var headerObj = (isDefault)?this._default_headers:this._http_headers;
797

    
798
        headerObj[label] = value;
799
        if(isDefault){
800
            this._has_default_headers = true;
801
        }
802
        else{
803
            this._has_http_headers = true;
804
        }
805
    },
806

    
807

    
808
  /**
809
  * @description Accessor that sets the HTTP headers for each transaction.
810
  * @method setHeader
811
  * @private
812
  * @static
813
  * @param {object} o The connection object for the transaction.
814
  * @return {void}
815
   */
816
    setHeader:function(o)
817
    {
818
        var prop;
819
        if(this._has_default_headers){
820
            for(prop in this._default_headers){
821
                if(YAHOO.lang.hasOwnProperty(this._default_headers, prop)){
822
                    o.conn.setRequestHeader(prop, this._default_headers[prop]);
823
                    YAHOO.log('Default HTTP header ' + prop + ' set with value of ' + this._default_headers[prop], 'info', 'Connection');
824
                }
825
            }
826
        }
827

    
828
        if(this._has_http_headers){
829
            for(prop in this._http_headers){
830
                if(YAHOO.lang.hasOwnProperty(this._http_headers, prop)){
831
                    o.conn.setRequestHeader(prop, this._http_headers[prop]);
832
                    YAHOO.log('HTTP header ' + prop + ' set with value of ' + this._http_headers[prop], 'info', 'Connection');
833
                }
834
            }
835

    
836
            this._http_headers = {};
837
            this._has_http_headers = false;
838
        }
839
    },
840

    
841
  /**
842
  * @description Resets the default HTTP headers object
843
  * @method resetDefaultHeaders
844
  * @public
845
  * @static
846
  * @return {void}
847
   */
848
    resetDefaultHeaders:function(){
849
        this._default_headers = {};
850
        this._has_default_headers = false;
851
    },
852

    
853
  /**
854
  * @description Method to terminate a transaction, if it has not reached readyState 4.
855
  * @method abort
856
  * @public
857
  * @static
858
  * @param {object} o The connection object returned by asyncRequest.
859
  * @param {object} callback  User-defined callback object.
860
  * @param {string} isTimeout boolean to indicate if abort resulted from a callback timeout.
861
  * @return {boolean}
862
   */
863
    abort:function(o, callback, isTimeout)
864
    {
865
        var abortStatus,
866
            args = (callback && callback.argument)?callback.argument:null;
867
            o = o || {};
868

    
869
        if(o.conn){
870
            if(o.xhr){
871
                if(this.isCallInProgress(o)){
872
                    // Issue abort request
873
                    o.conn.abort();
874

    
875
                    window.clearInterval(this._poll[o.tId]);
876
                    delete this._poll[o.tId];
877

    
878
                    if(isTimeout){
879
                        window.clearTimeout(this._timeOut[o.tId]);
880
                        delete this._timeOut[o.tId];
881
                    }
882

    
883
                    abortStatus = true;
884
                }
885
            }
886
            else if(o.xdr){
887
                o.conn.abort(o.tId);
888
                abortStatus = true;
889
            }
890
        }
891
        else if(o.upload){
892
            var frameId = 'yuiIO' + o.tId;
893
            var io = document.getElementById(frameId);
894

    
895
            if(io){
896
                // Remove all listeners on the iframe prior to
897
                // its destruction.
898
                YAHOO.util.Event.removeListener(io, "load");
899
                // Destroy the iframe facilitating the transaction.
900
                document.body.removeChild(io);
901
                YAHOO.log('File upload iframe destroyed. Id is:' + frameId, 'info', 'Connection');
902

    
903
                if(isTimeout){
904
                    window.clearTimeout(this._timeOut[o.tId]);
905
                    delete this._timeOut[o.tId];
906
                }
907

    
908
                abortStatus = true;
909
            }
910
        }
911
        else{
912
            abortStatus = false;
913
        }
914

    
915
        if(abortStatus === true){
916
            // Fire global custom event -- abortEvent
917
            this.abortEvent.fire(o, args);
918

    
919
            if(o.abortEvent){
920
                // Fire transaction custom event -- abortEvent
921
                o.abortEvent.fire(o, args);
922
            }
923

    
924
            this.handleTransactionResponse(o, callback, true);
925
            YAHOO.log('Transaction ' + o.tId + ' aborted.', 'info', 'Connection');
926
        }
927

    
928
        return abortStatus;
929
    },
930

    
931
  /**
932
  * @description Determines if the transaction is still being processed.
933
  * @method isCallInProgress
934
  * @public
935
  * @static
936
  * @param {object} o The connection object returned by asyncRequest
937
  * @return {boolean}
938
   */
939
    isCallInProgress:function(o)
940
    {
941
        o = o || {};
942
        // if the XHR object assigned to the transaction has not been dereferenced,
943
        // then check its readyState status.  Otherwise, return false.
944
        if(o.xhr && o.conn){
945
            return o.conn.readyState !== 4 && o.conn.readyState !== 0;
946
        }
947
        else if(o.xdr && o.conn){
948
            return o.conn.isCallInProgress(o.tId);
949
        }
950
        else if(o.upload === true){
951
            return document.getElementById('yuiIO' + o.tId)?true:false;
952
        }
953
        else{
954
            return false;
955
        }
956
    },
957

    
958
  /**
959
  * @description Dereference the XHR instance and the connection object after the transaction is completed.
960
  * @method releaseObject
961
  * @private
962
  * @static
963
  * @param {object} o The connection object
964
  * @return {void}
965
   */
966
    releaseObject:function(o)
967
    {
968
        if(o && o.conn){
969
            //dereference the XHR instance.
970
            o.conn = null;
971

    
972
            YAHOO.log('Connection object for transaction ' + o.tId + ' destroyed.', 'info', 'Connection');
973

    
974
            //dereference the connection object.
975
            o = null;
976
        }
977
    }
978
};
979

    
980
YAHOO.register("connection_core", YAHOO.util.Connect, {version: "2.8.0r4", build: "2449"});
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