Removes unnecessary test and ensures getResponseHeader returns null if the header...
[jquery.git] / src / ajax.js
1 (function( jQuery ) {
2
3 var r20 = /%20/g,
4         rbracket = /\[\]$/,
5         rhash = /#.*$/,
6         rheaders = /^(.*?):\s*(.*?)\r?$/mg, // IE leaves an \r character at EOL
7         rinput = /^(?:color|date|datetime|email|hidden|month|number|password|range|search|tel|text|time|url|week)$/i,
8         rnoContent = /^(?:GET|HEAD)$/,
9         rquery = /\?/,
10         rscript = /<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi,
11         rselectTextarea = /^(?:select|textarea)/i,
12         rts = /([?&])_=[^&]*/,
13         rurl = /^(\w+:)?\/\/([^\/?#:]+)(?::(\d+))?/,
14         rCRLF = /\r?\n/g,
15
16         // Slice function
17         sliceFunc = Array.prototype.slice,
18
19         // Keep a copy of the old load method
20         _load = jQuery.fn.load;
21
22 jQuery.fn.extend({
23         load: function( url, params, callback ) {
24                 if ( typeof url !== "string" && _load ) {
25                         return _load.apply( this, arguments );
26
27                 // Don't do a request if no elements are being requested
28                 } else if ( !this.length ) {
29                         return this;
30                 }
31
32                 var off = url.indexOf(" ");
33                 if ( off >= 0 ) {
34                         var selector = url.slice(off, url.length);
35                         url = url.slice(0, off);
36                 }
37
38                 // Default to a GET request
39                 var type = "GET";
40
41                 // If the second parameter was provided
42                 if ( params ) {
43                         // If it's a function
44                         if ( jQuery.isFunction( params ) ) {
45                                 // We assume that it's the callback
46                                 callback = params;
47                                 params = null;
48
49                         // Otherwise, build a param string
50                         } else if ( typeof params === "object" ) {
51                                 params = jQuery.param( params, jQuery.ajaxSettings.traditional );
52                                 type = "POST";
53                         }
54                 }
55
56                 var self = this;
57
58                 // Request the remote document
59                 jQuery.ajax({
60                         url: url,
61                         type: type,
62                         dataType: "html",
63                         data: params,
64                         // Complete callback (responseText is used internally)
65                         complete: function( jXHR, status, responseText ) {
66                                 // Store the response as specified by the jXHR object
67                                 responseText = jXHR.responseText;
68                                 // If successful, inject the HTML into all the matched elements
69                                 if ( jXHR.isResolved() ) {
70                                         // #4825: Get the actual response in case
71                                         // a dataFilter is present in ajaxSettings
72                                         jXHR.done(function( r ) {
73                                                 responseText = r;
74                                         });
75                                         // See if a selector was specified
76                                         self.html( selector ?
77                                                 // Create a dummy div to hold the results
78                                                 jQuery("<div>")
79                                                         // inject the contents of the document in, removing the scripts
80                                                         // to avoid any 'Permission Denied' errors in IE
81                                                         .append(responseText.replace(rscript, ""))
82
83                                                         // Locate the specified elements
84                                                         .find(selector) :
85
86                                                 // If not, just inject the full result
87                                                 responseText );
88                                 }
89
90                                 if ( callback ) {
91                                         self.each( callback, [responseText, status, jXHR] );
92                                 }
93                         }
94                 });
95
96                 return this;
97         },
98
99         serialize: function() {
100                 return jQuery.param(this.serializeArray());
101         },
102
103         serializeArray: function() {
104                 return this.map(function(){
105                         return this.elements ? jQuery.makeArray(this.elements) : this;
106                 })
107                 .filter(function(){
108                         return this.name && !this.disabled &&
109                                 (this.checked || rselectTextarea.test(this.nodeName) ||
110                                         rinput.test(this.type));
111                 })
112                 .map(function(i, elem){
113                         var val = jQuery(this).val();
114
115                         return val == null ?
116                                 null :
117                                 jQuery.isArray(val) ?
118                                         jQuery.map( val, function(val, i){
119                                                 return { name: elem.name, value: val.replace(rCRLF, "\r\n") };
120                                         }) :
121                                         { name: elem.name, value: val.replace(rCRLF, "\r\n") };
122                 }).get();
123         }
124 });
125
126 // Attach a bunch of functions for handling common AJAX events
127 jQuery.each( "ajaxStart ajaxStop ajaxComplete ajaxError ajaxSuccess ajaxSend".split(" "), function(i,o){
128         jQuery.fn[o] = function(f){
129                 return this.bind(o, f);
130         };
131 });
132
133 jQuery.each( [ "get", "post" ], function( i, method ) {
134         jQuery[ method ] = function( url, data, callback, type ) {
135                 // shift arguments if data argument was omited
136                 if ( jQuery.isFunction( data ) ) {
137                         type = type || callback;
138                         callback = data;
139                         data = null;
140                 }
141
142                 return jQuery.ajax({
143                         type: method,
144                         url: url,
145                         data: data,
146                         success: callback,
147                         dataType: type
148                 });
149         };
150 });
151
152 jQuery.extend({
153
154         getScript: function( url, callback ) {
155                 return jQuery.get(url, null, callback, "script");
156         },
157
158         getJSON: function( url, data, callback ) {
159                 return jQuery.get(url, data, callback, "json");
160         },
161
162         ajaxSetup: function( settings ) {
163                 jQuery.extend( true, jQuery.ajaxSettings, settings );
164                 return this;
165         },
166
167         ajaxSettings: {
168                 url: location.href,
169                 global: true,
170                 type: "GET",
171                 contentType: "application/x-www-form-urlencoded",
172                 processData: true,
173                 async: true,
174                 /*
175                 timeout: 0,
176                 data: null,
177                 dataType: null,
178                 username: null,
179                 password: null,
180                 cache: null,
181                 traditional: false,
182                 headers: {},
183                 crossDomain: null,
184                 */
185
186                 accepts: {
187                         xml: "application/xml, text/xml",
188                         html: "text/html",
189                         text: "text/plain",
190                         json: "application/json, text/javascript",
191                         "*": "*/*"
192                 },
193
194                 contents: {
195                         xml: /xml/,
196                         html: /html/,
197                         json: /json/
198                 },
199
200                 // Prefilters
201                 // 1) They are useful to introduce custom dataTypes (see transport/jsonp for an example)
202                 // 2) These are called:
203                 //    * BEFORE asking for a transport
204                 //    * AFTER param serialization (s.data is a string if s.processData is true)
205                 // 3) key is the dataType
206                 // 4) the catchall symbol "*" can be used
207                 // 5) execution will start with transport dataType and THEN continue down to "*" if needed
208                 prefilters: {},
209
210                 // Transports bindings
211                 // 1) key is the dataType
212                 // 2) the catchall symbol "*" can be used
213                 // 3) selection will start with transport dataType and THEN go to "*" if needed
214                 transports: {},
215
216                 // List of data converters
217                 // 1) key format is "source_type destination_type" (a single space in-between)
218                 // 2) the catchall symbol "*" can be used for source_type
219                 converters: {
220
221                         // Convert anything to text
222                         "* text": window.String,
223
224                         // Text to html (true = no transformation)
225                         "text html": true,
226
227                         // Evaluate text as a json expression
228                         "text json": jQuery.parseJSON,
229
230                         // Parse text as xml
231                         "text xml": jQuery.parseXML
232                 }
233         },
234
235         // Main method
236         ajax: function( url , options ) {
237
238                 // Handle varargs
239                 if ( arguments.length === 1 ) {
240                         options = url;
241                         url = options ? options.url : undefined;
242                 }
243
244                 // Force options to be an object
245                 options = options || {};
246
247                 // Get the url if provided separately
248                 options.url = url || options.url;
249
250                 var // Create the final options object
251                         s = jQuery.extend( true , {} , jQuery.ajaxSettings , options ),
252                         // jQuery lists
253                         jQuery_lastModified = jQuery.lastModified,
254                         jQuery_etag = jQuery.etag,
255                         // Callbacks contexts
256                         callbackContext = options.context || s.context || s,
257                         globalEventContext = callbackContext === s ? jQuery.event : jQuery( callbackContext ),
258                         // Deferreds
259                         deferred = jQuery.Deferred(),
260                         completeDeferred = jQuery._Deferred(),
261                         // Status-dependent callbacks
262                         statusCode = s.statusCode || {},
263                         // Headers (they are sent all at once)
264                         requestHeaders = {},
265                         // Response headers
266                         responseHeadersString,
267                         responseHeaders,
268                         // transport
269                         transport,
270                         // timeout handle
271                         timeoutTimer,
272                         // Cross-domain detection vars
273                         loc = document.location,
274                         parts,
275                         // The jXHR state
276                         state = 0,
277                         // Loop variable
278                         i,
279                         // Fake xhr
280                         jXHR = {
281
282                                 readyState: 0,
283
284                                 // Caches the header
285                                 setRequestHeader: function(name,value) {
286                                         if ( state === 0 ) {
287                                                 requestHeaders[ name.toLowerCase() ] = value;
288                                         }
289                                         return this;
290                                 },
291
292                                 // Raw string
293                                 getAllResponseHeaders: function() {
294                                         return state === 2 ? responseHeadersString : null;
295                                 },
296
297                                 // Builds headers hashtable if needed
298                                 getResponseHeader: function( key ) {
299
300                                         var match;
301
302                                         if ( state === 2 ) {
303
304                                                 if ( !responseHeaders ) {
305
306                                                         responseHeaders = {};
307
308                                                         while( ( match = rheaders.exec( responseHeadersString ) ) ) {
309                                                                 responseHeaders[ match[ 1 ].toLowerCase() ] = match[ 2 ];
310                                                         }
311                                                 }
312                                                 match = responseHeaders[ key.toLowerCase() ];
313
314                                         }
315
316                                         return match || null;
317                                 },
318
319                                 // Cancel the request
320                                 abort: function( statusText ) {
321                                         if ( transport ) {
322                                                 transport.abort( statusText || "abort" );
323                                         }
324                                         done( 0 , statusText );
325                                         return this;
326                                 }
327                         };
328
329                 // We force the original context
330                 // (plain objects used as context get extended)
331                 s.context = options.context;
332
333                 // Callback for when everything is done
334                 // It is defined here because jslint complains if it is declared
335                 // at the end of the function (which would be more logical and readable)
336                 function done( status , statusText , response , headers) {
337
338                         // Called once
339                         if ( state === 2 ) {
340                                 return;
341                         }
342
343                         // State is "done" now
344                         state = 2;
345
346                         // Dereference transport for early garbage collection
347                         // (no matter how long the jXHR transport will be used
348                         transport = 0;
349
350                         // Set readyState
351                         jXHR.readyState = status ? 4 : 0;
352
353                         // Cache response headers
354                         responseHeadersString = headers || "";
355
356                         // Clear timeout if it exists
357                         if ( timeoutTimer ) {
358                                 clearTimeout(timeoutTimer);
359                         }
360
361                         var // Reference url
362                                 url = s.url,
363                                 // and ifModified status
364                                 ifModified = s.ifModified,
365
366                                 // Is it a success?
367                                 isSuccess = 0,
368                                 // Stored success
369                                 success,
370                                 // Stored error
371                                 error;
372
373                         // If successful, handle type chaining
374                         if ( status >= 200 && status < 300 || status === 304 ) {
375
376                                 // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
377                                 if ( s.ifModified ) {
378
379                                         var lastModified = jXHR.getResponseHeader("Last-Modified"),
380                                                 etag = jXHR.getResponseHeader("Etag");
381
382                                         if (lastModified) {
383                                                 jQuery_lastModified[ s.url ] = lastModified;
384                                         }
385                                         if (etag) {
386                                                 jQuery_etag[ s.url ] = etag;
387                                         }
388                                 }
389
390                                 // If not modified
391                                 if ( status === 304 ) {
392
393                                         // Set the statusText accordingly
394                                         statusText = "notmodified";
395                                         // Mark as a success
396                                         isSuccess = 1;
397
398                                 // If we have data
399                                 } else {
400
401                                         // Set the statusText accordingly
402                                         statusText = "success";
403
404                                         // Chain data conversions and determine the final value
405                                         // (if an exception is thrown in the process, it'll be notified as an error)
406                                         try {
407
408                                                 var i,
409                                                         // Current dataType
410                                                         current,
411                                                         // Previous dataType
412                                                         prev,
413                                                         // Conversion function
414                                                         conv,
415                                                         // Conversion functions (when text is used in-between)
416                                                         conv1,
417                                                         conv2,
418                                                         // Local references to dataTypes & converters
419                                                         dataTypes = s.dataTypes,
420                                                         converters = s.converters,
421                                                         // DataType to responseXXX field mapping
422                                                         responses = {
423                                                                 "xml": "XML",
424                                                                 "text": "Text"
425                                                         };
426
427                                                 // For each dataType in the chain
428                                                 for( i = 0 ; i < dataTypes.length ; i++ ) {
429
430                                                         current = dataTypes[ i ];
431
432                                                         // If a responseXXX field for this dataType exists
433                                                         // and if it hasn't been set yet
434                                                         if ( responses[ current ] ) {
435                                                                 // Set it
436                                                                 jXHR[ "response" + responses[ current ] ] = response;
437                                                                 // Mark it as set
438                                                                 responses[ current ] = 0;
439                                                         }
440
441                                                         // If this is not the first element
442                                                         if ( i ) {
443
444                                                                 // Get the dataType to convert from
445                                                                 prev = dataTypes[ i - 1 ];
446
447                                                                 // If no catch-all and dataTypes are actually different
448                                                                 if ( prev !== "*" && current !== "*" && prev !== current ) {
449
450                                                                         // Get the converter
451                                                                         conv = converters[ prev + " " + current ] ||
452                                                                                 converters[ "* " + current ];
453
454                                                                         conv1 = conv2 = 0;
455
456                                                                         // If there is no direct converter and none of the dataTypes is text
457                                                                         if ( ! conv && prev !== "text" && current !== "text" ) {
458                                                                                 // Try with text in-between
459                                                                                 conv1 = converters[ prev + " text" ] || converters[ "* text" ];
460                                                                                 conv2 = converters[ "text " + current ];
461                                                                                 // Revert back to a single converter
462                                                                                 // if one of the converter is an equivalence
463                                                                                 if ( conv1 === true ) {
464                                                                                         conv = conv2;
465                                                                                 } else if ( conv2 === true ) {
466                                                                                         conv = conv1;
467                                                                                 }
468                                                                         }
469                                                                         // If we found no converter, dispatch an error
470                                                                         if ( ! ( conv || conv1 && conv2 ) ) {
471                                                                                 throw conversion;
472                                                                         }
473                                                                         // If found converter is not an equivalence
474                                                                         if ( conv !== true ) {
475                                                                                 // Convert with 1 or 2 converters accordingly
476                                                                                 response = conv ? conv( response ) : conv2( conv1( response ) );
477                                                                         }
478                                                                 }
479                                                         // If it is the first element of the chain
480                                                         // and we have a dataFilter
481                                                         } else if ( s.dataFilter ) {
482                                                                 // Apply the dataFilter
483                                                                 response = s.dataFilter( response , current );
484                                                                 // Get dataTypes again in case the filter changed them
485                                                                 dataTypes = s.dataTypes;
486                                                         }
487                                                 }
488                                                 // End of loop
489
490                                                 // We have a real success
491                                                 success = response;
492                                                 isSuccess = 1;
493
494                                         // If an exception was thrown
495                                         } catch(e) {
496
497                                                 // We have a parsererror
498                                                 statusText = "parsererror";
499                                                 error = "" + e;
500
501                                         }
502                                 }
503
504                         // if not success, mark it as an error
505                         } else {
506
507                                         error = statusText = statusText || "error";
508
509                                         // Set responseText if needed
510                                         if ( response ) {
511                                                 jXHR.responseText = response;
512                                         }
513                         }
514
515                         // Set data for the fake xhr object
516                         jXHR.status = status;
517                         jXHR.statusText = statusText;
518
519                         // Success/Error
520                         if ( isSuccess ) {
521                                 deferred.fire( callbackContext , [ success , statusText , jXHR ] );
522                         } else {
523                                 deferred.fireReject( callbackContext , [ jXHR , statusText , error ] );
524                         }
525
526                         // Status-dependent callbacks
527                         jXHR.statusCode( statusCode );
528
529                         if ( s.global ) {
530                                 globalEventContext.trigger( "ajax" + ( isSuccess ? "Success" : "Error" ) ,
531                                                 [ jXHR , s , isSuccess ? success : error ] );
532                         }
533
534                         // Complete
535                         completeDeferred.fire( callbackContext, [ jXHR , statusText ] );
536
537                         if ( s.global ) {
538                                 globalEventContext.trigger( "ajaxComplete" , [ jXHR , s] );
539                                 // Handle the global AJAX counter
540                                 if ( ! --jQuery.active ) {
541                                         jQuery.event.trigger( "ajaxStop" );
542                                 }
543                         }
544                 }
545
546                 // Attach deferreds
547                 deferred.promise( jXHR );
548                 jXHR.success = jXHR.done;
549                 jXHR.error = jXHR.fail;
550                 jXHR.complete = completeDeferred.done;
551
552                 // Status-dependent callbacks
553                 jXHR.statusCode = function( map ) {
554                         if ( map ) {
555                                 var resolved = jXHR.isResolved(),
556                                         tmp;
557                                 if ( resolved || jXHR.isRejected() ) {
558                                         tmp = map[ jXHR.status ];
559                                         if ( tmp ) {
560                                                 if ( map === statusCode ) {
561                                                         delete statusCode[ jXHR.status ];
562                                                 }
563                                                 jXHR[ resolved ? "done" : "fail" ]( tmp );
564                                         }
565                                 } else {
566                                         for( tmp in map ) {
567                                                 statusCode[ tmp ] = [ statusCode[ tmp ] , map[ tmp ] ];
568                                         }
569                                 }
570                         }
571                         return this;
572                 };
573
574                 // Remove hash character (#7531: and string promotion)
575                 s.url = ( "" + s.url ).replace( rhash , "" );
576
577                 // Extract dataTypes list
578                 s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().split( /\s+/ );
579
580                 // Determine if a cross-domain request is in order
581                 if ( ! s.crossDomain ) {
582                         parts = rurl.exec( s.url.toLowerCase() );
583                         s.crossDomain = !!(
584                                         parts &&
585                                         ( parts[ 1 ] && parts[ 1 ] != loc.protocol ||
586                                                 parts[ 2 ] != loc.hostname ||
587                                                 ( parts[ 3 ] || 80 ) != ( loc.port || 80 ) )
588                         );
589                 }
590
591                 // Convert data if not already a string
592                 if ( s.data && s.processData && typeof s.data !== "string" ) {
593                         s.data = jQuery.param( s.data , s.traditional );
594                 }
595
596                 // Apply prefilters
597                 jQuery.ajaxPrefilter( s , options );
598
599                 // Uppercase the type
600                 s.type = s.type.toUpperCase();
601
602                 // Determine if request has content
603                 s.hasContent = ! rnoContent.test( s.type );
604
605                 // Watch for a new set of requests
606                 if ( s.global && jQuery.active++ === 0 ) {
607                         jQuery.event.trigger( "ajaxStart" );
608                 }
609
610                 // More options handling for requests with no content
611                 if ( ! s.hasContent ) {
612
613                         // If data is available, append data to url
614                         if ( s.data ) {
615                                 s.url += ( rquery.test( s.url ) ? "&" : "?" ) + s.data;
616                         }
617
618                         // Add anti-cache in url if needed
619                         if ( s.cache === false ) {
620
621                                 var ts = jQuery.now(),
622                                         // try replacing _= if it is there
623                                         ret = s.url.replace( rts , "$1_=" + ts );
624
625                                 // if nothing was replaced, add timestamp to the end
626                                 s.url = ret + ( (ret == s.url ) ? ( rquery.test( s.url ) ? "&" : "?" ) + "_=" + ts : "");
627                         }
628                 }
629
630                 // Set the correct header, if data is being sent
631                 if ( s.data && s.hasContent && s.contentType !== false || options.contentType ) {
632                         requestHeaders[ "content-type" ] = s.contentType;
633                 }
634
635                 // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
636                 if ( s.ifModified ) {
637                         if ( jQuery_lastModified[ s.url ] ) {
638                                 requestHeaders[ "if-modified-since" ] = jQuery_lastModified[ s.url ];
639                         }
640                         if ( jQuery_etag[ s.url ] ) {
641                                 requestHeaders[ "if-none-match" ] = jQuery_etag[ s.url ];
642                         }
643                 }
644
645                 // Set the Accepts header for the server, depending on the dataType
646                 requestHeaders.accept = s.dataTypes[ 0 ] && s.accepts[ s.dataTypes[ 0 ] ] ?
647                         s.accepts[ s.dataTypes[ 0 ] ] + ( s.dataTypes[ 0 ] !== "*" ? ", */*; q=0.01" : "" ) :
648                         s.accepts[ "*" ];
649
650                 // Check for headers option
651                 for ( i in s.headers ) {
652                         requestHeaders[ i.toLowerCase() ] = s.headers[ i ];
653                 }
654
655                 // Allow custom headers/mimetypes and early abort
656                 if ( s.beforeSend && ( s.beforeSend.call( callbackContext , jXHR , s ) === false || state === 2 ) ) {
657
658                                 // Abort if not done already
659                                 done( 0 , "abort" );
660
661                                 // Return false
662                                 jXHR = false;
663
664                 } else {
665
666                         // Install callbacks on deferreds
667                         for ( i in { success:1, error:1, complete:1 } ) {
668                                 jXHR[ i ]( s[ i ] );
669                         }
670
671                         // Get transport
672                         transport = jQuery.ajaxTransport( s );
673
674                         // If no transport, we auto-abort
675                         if ( ! transport ) {
676
677                                 done( 0 , "notransport" );
678
679                         } else {
680
681                                 // Set state as sending
682                                 state = jXHR.readyState = 1;
683
684                                 // Send global event
685                                 if ( s.global ) {
686                                         globalEventContext.trigger( "ajaxSend" , [ jXHR , s ] );
687                                 }
688
689                                 // Timeout
690                                 if ( s.async && s.timeout > 0 ) {
691                                         timeoutTimer = setTimeout(function(){
692                                                 jXHR.abort( "timeout" );
693                                         }, s.timeout);
694                                 }
695
696                                 // Try to send
697                                 try {
698                                         transport.send(requestHeaders, done);
699                                 } catch (e) {
700                                         // Propagate exception as error if not done
701                                         if ( status === 1 ) {
702
703                                                 done(0, "error", "" + e);
704                                                 jXHR = false;
705
706                                         // Simply rethrow otherwise
707                                         } else {
708                                                 jQuery.error(e);
709                                         }
710                                 }
711                         }
712                 }
713
714                 return jXHR;
715         },
716
717         // Serialize an array of form elements or a set of
718         // key/values into a query string
719         param: function( a, traditional ) {
720                 var s = [],
721                         add = function( key, value ) {
722                                 // If value is a function, invoke it and return its value
723                                 value = jQuery.isFunction(value) ? value() : value;
724                                 s[ s.length ] = encodeURIComponent(key) + "=" + encodeURIComponent(value);
725                         };
726
727                 // Set traditional to true for jQuery <= 1.3.2 behavior.
728                 if ( traditional === undefined ) {
729                         traditional = jQuery.ajaxSettings.traditional;
730                 }
731
732                 // If an array was passed in, assume that it is an array of form elements.
733                 if ( jQuery.isArray(a) || a.jquery ) {
734                         // Serialize the form elements
735                         jQuery.each( a, function() {
736                                 add( this.name, this.value );
737                         });
738
739                 } else {
740                         // If traditional, encode the "old" way (the way 1.3.2 or older
741                         // did it), otherwise encode params recursively.
742                         for ( var prefix in a ) {
743                                 buildParams( prefix, a[prefix], traditional, add );
744                         }
745                 }
746
747                 // Return the resulting serialization
748                 return s.join("&").replace(r20, "+");
749         }
750 });
751
752 function buildParams( prefix, obj, traditional, add ) {
753         if ( jQuery.isArray(obj) && obj.length ) {
754                 // Serialize array item.
755                 jQuery.each( obj, function( i, v ) {
756                         if ( traditional || rbracket.test( prefix ) ) {
757                                 // Treat each array item as a scalar.
758                                 add( prefix, v );
759
760                         } else {
761                                 // If array item is non-scalar (array or object), encode its
762                                 // numeric index to resolve deserialization ambiguity issues.
763                                 // Note that rack (as of 1.0.0) can't currently deserialize
764                                 // nested arrays properly, and attempting to do so may cause
765                                 // a server error. Possible fixes are to modify rack's
766                                 // deserialization algorithm or to provide an option or flag
767                                 // to force array serialization to be shallow.
768                                 buildParams( prefix + "[" + ( typeof v === "object" || jQuery.isArray(v) ? i : "" ) + "]", v, traditional, add );
769                         }
770                 });
771
772         } else if ( !traditional && obj != null && typeof obj === "object" ) {
773                 // If we see an array here, it is empty and should be treated as an empty
774                 // object
775                 if ( jQuery.isArray( obj ) || jQuery.isEmptyObject( obj ) ) {
776                         add( prefix, "" );
777
778                 // Serialize object item.
779                 } else {
780                         jQuery.each( obj, function( k, v ) {
781                                 buildParams( prefix + "[" + k + "]", v, traditional, add );
782                         });
783                 }
784
785         } else {
786                 // Serialize scalar item.
787                 add( prefix, obj );
788         }
789 }
790
791 // This is still on the jQuery object... for now
792 // Want to move this to jQuery.ajax some day
793 jQuery.extend({
794
795         // Counter for holding the number of active queries
796         active: 0,
797
798         // Last-Modified header cache for next request
799         lastModified: {},
800         etag: {}
801
802 });
803
804 //Execute or select from functions in a given structure of options
805 function ajax_selectOrExecute( structure , s ) {
806
807         var dataTypes = s.dataTypes,
808                 transportDataType,
809                 list,
810                 selected,
811                 i,
812                 length,
813                 checked = {},
814                 flag,
815                 noSelect = structure !== "transports";
816
817         function initSearch( dataType ) {
818
819                 flag = transportDataType !== dataType && ! checked[ dataType ];
820
821                 if ( flag ) {
822
823                         checked[ dataType ] = 1;
824                         transportDataType = dataType;
825                         list = s[ structure ][ dataType ];
826                         i = -1;
827                         length = list ? list.length : 0 ;
828                 }
829
830                 return flag;
831         }
832
833         initSearch( dataTypes[ 0 ] );
834
835         for ( i = 0 ; ( noSelect || ! selected ) && i <= length ; i++ ) {
836
837                 if ( i === length ) {
838
839                         initSearch( "*" );
840
841                 } else {
842
843                         selected = list[ i ]( s , determineDataType );
844
845                         // If we got redirected to another dataType
846                         // Search there (if not in progress or already tried)
847                         if ( typeof( selected ) === "string" &&
848                                 initSearch( selected ) ) {
849
850                                 dataTypes.unshift( selected );
851                                 selected = 0;
852                         }
853                 }
854         }
855
856         return noSelect ? jQuery : selected;
857 }
858
859 // Add an element to one of the structures in ajaxSettings
860 function ajax_addElement( structure , args ) {
861
862         var i,
863                 start = 0,
864                 length = args.length,
865                 dataTypes = [ "*" ],
866                 dLength = 1,
867                 dataType,
868                 functors = [],
869                 first,
870                 append,
871                 list;
872
873         if ( length ) {
874
875                 first = jQuery.type( args[ 0 ] );
876
877                 if ( first === "object" ) {
878                         return ajax_selectOrExecute( structure , args[ 0 ] );
879                 }
880
881                 structure = jQuery.ajaxSettings[ structure ];
882
883                 if ( first !== "function" ) {
884
885                         dataTypes = args[ 0 ].toLowerCase().split(/\s+/);
886                         dLength = dataTypes.length;
887                         start = 1;
888
889                 }
890
891                 if ( dLength && start < length ) {
892
893                         functors = sliceFunc.call( args , start );
894
895                         for( i = 0 ; i < dLength ; i++ ) {
896
897                                 dataType = dataTypes[ i ];
898
899                                 first = /^\+/.test( dataType );
900
901                                 if (first) {
902                                         dataType = dataType.substr(1);
903                                 }
904
905                                 if ( dataType !== "" ) {
906
907                                         append = Array.prototype[ first ? "unshift" : "push" ];
908                                         list = structure[ dataType ] = structure[ dataType ] || [];
909                                         append.apply( list , functors );
910                                 }
911                         }
912                 }
913         }
914
915         return jQuery;
916 }
917
918 // Install prefilter & transport methods
919 jQuery.each( [ "Prefilter" , "Transport" ] , function( _ , name ) {
920         _ = name.toLowerCase() + "s";
921         jQuery[ "ajax" + name ] = function() {
922                 return ajax_addElement( _ , arguments );
923         };
924 } );
925
926 // Utility function that handles dataType when response is received
927 // (for those transports that can give text or xml responses)
928 function determineDataType( s , ct , text , xml ) {
929
930         var contents = s.contents,
931                 type,
932                 regexp,
933                 dataTypes = s.dataTypes,
934                 transportDataType = dataTypes[0],
935                 response;
936
937         // Auto (xml, json, script or text determined given headers)
938         if ( transportDataType === "*" ) {
939
940                 for ( type in contents ) {
941                         if ( ( regexp = contents[ type ] ) && regexp.test( ct ) ) {
942                                 transportDataType = dataTypes[0] = type;
943                                 break;
944                         }
945                 }
946         }
947
948         // xml and parsed as such
949         if ( transportDataType === "xml" &&
950                 xml &&
951                 xml.documentElement /* #4958 */ ) {
952
953                 response = xml;
954
955         // Text response was provided
956         } else {
957
958                 response = text;
959
960                 // If it's not really text, defer to converters
961                 if ( transportDataType !== "text" ) {
962                         dataTypes.unshift( "text" );
963                 }
964
965         }
966
967         return response;
968 }
969
970 })( jQuery );