src/ajax/xhr.js

   1 (function( jQuery ) {
   2
   3 var // Next fake timer id
   4         xhrPollingId = jQuery.now(),
   5
   6         // Callbacks hashtable
   7         xhrs = {},
   8
   9         // XHR pool
  10         xhrPool = [],
  11
  12         // #5280: see end of file
  13         xhrUnloadAbortMarker = [];
  14
  15
  16 jQuery.ajax.transport( function( s , determineDataType ) {
  17
  18         // Cross domain only allowed if supported through XMLHttpRequest
  19         if ( ! s.crossDomain || jQuery.support.cors ) {
  20
  21                 var callback;
  22
  23                 return {
  24
  25                         send: function(headers, complete) {
  26
  27                                 var xhr = xhrPool.pop() || s.xhr(),
  28                                         handle;
  29
  30                                 // Open the socket
  31                                 // Passing null username, generates a login popup on Opera (#2865)
  32                                 if ( s.username ) {
  33                                         xhr.open(s.type, s.url, s.async, s.username, s.password);
  34                                 } else {
  35                                         xhr.open(s.type, s.url, s.async);
  36                                 }
  37
  38                                 // Requested-With header
  39                                 // Not set for crossDomain requests with no content
  40                                 // (see why at http://trac.dojotoolkit.org/ticket/9486)
  41                                 // Won't change header if already provided in beforeSend
  42                                 if ( ! ( s.crossDomain && ! s.hasContent ) && ! headers["x-requested-with"] ) {
  43                                         headers["x-requested-with"] = "XMLHttpRequest";
  44                                 }
  45
  46                                 // Need an extra try/catch for cross domain requests in Firefox 3
  47                                 try {
  48
  49                                         jQuery.each(headers, function(key,value) {
  50                                                 xhr.setRequestHeader(key,value);
  51                                         });
  52
  53                                 } catch(_) {}
  54
  55                                 // Do send the request
  56                                 try {
  57                                         xhr.send( ( s.hasContent && s.data ) || null );
  58                                 } catch(e) {
  59                                         // Store back in pool
  60                                         xhrPool.push( xhr );
  61                                         complete(0, "error", "" + e);
  62                                         return;
  63                                 }
  64
  65                                 // Listener
  66                                 callback = function ( abortStatusText ) {
  67
  68                                         // Was never called and is aborted or complete
  69                                         if ( callback && ( abortStatusText || xhr.readyState === 4 ) ) {
  70
  71                                                 // Do not listen anymore
  72                                                 // and Store back in pool
  73                                                 if (handle) {
  74                                                         xhr.onreadystatechange = jQuery.noop;
  75                                                         delete xhrs[ handle ];
  76                                                         handle = undefined;
  77                                                         xhrPool.push( xhr );
  78                                                 }
  79
  80                                                 callback = 0;
  81
  82                                                 // Get info
  83                                                 var status, statusText, response, responseHeaders;
  84
  85                                                 if ( abortStatusText ) {
  86
  87                                                         if ( xhr.readyState !== 4 ) {
  88                                                                 xhr.abort();
  89                                                         }
  90
  91                                                         // Stop here if unloadAbort
  92                                                         if ( abortStatusText === xhrUnloadAbortMarker ) {
  93                                                                 return;
  94                                                         }
  95
  96                                                         status = 0;
  97                                                         statusText = abortStatusText;
  98
  99                                                 } else {
 100
 101                                                         status = xhr.status;
 102
 103                                                         try { // Firefox throws an exception when accessing statusText for faulty cross-domain requests
 104
 105                                                                 statusText = xhr.statusText;
 106
 107                                                         } catch( e ) {
 108
 109                                                                 statusText = ""; // We normalize with Webkit giving an empty statusText
 110
 111                                                         }
 112
 113                                                         responseHeaders = xhr.getAllResponseHeaders();
 114
 115                                                         // Filter status for non standard behaviours
 116                                                         // (so many they seem to be the actual "standard")
 117                                                         status =
 118                                                                 // Opera returns 0 when it should be 304
 119                                                                 // Webkit returns 0 for failing cross-domain no matter the real status
 120                                                                 status === 0 ?
 121                                                                         (
 122                                                                                 ! s.crossDomain || statusText ? // Webkit, Firefox: filter out faulty cross-domain requests
 123                                                                                 (
 124                                                                                         responseHeaders ? // Opera: filter out real aborts #6060
 125                                                                                         304
 126                                                                                         :
 127                                                                                         0
 128                                                                                 )
 129                                                                                 :
 130                                                                                 302 // We assume 302 but could be anything cross-domain related
 131                                                                         )
 132                                                                         :
 133                                                                         (
 134                                                                                 status == 1223 ?        // IE sometimes returns 1223 when it should be 204 (see #1450)
 135                                                                                         204
 136                                                                                         :
 137                                                                                         status
 138                                                                         );
 139
 140                                                         // Guess response & update dataType accordingly
 141                                                         response =
 142                                                                 determineDataType(
 143                                                                         s,
 144                                                                         xhr.getResponseHeader("content-type"),
 145                                                                         xhr.responseText,
 146                                                                         xhr.responseXML );
 147                                                 }
 148
 149                                                 // Call complete
 150                                                 complete(status,statusText,response,responseHeaders);
 151                                         }
 152                                 };
 153
 154                                 // if we're in sync mode
 155                                 // or it's in cache and has been retrieved directly (IE6 & IE7)
 156                                 // we need to manually fire the callback
 157                                 if ( ! s.async || xhr.readyState === 4 ) {
 158
 159                                         callback();
 160
 161                                 } else {
 162
 163                                         // Listener is externalized to handle abort on unload
 164                                         handle = xhrPollingId++;
 165                                         xhrs[ handle ] = xhr;
 166                                         xhr.onreadystatechange = function() {
 167                                                 callback();
 168                                         };
 169                                 }
 170                         },
 171
 172                         abort: function(statusText) {
 173                                 if ( callback ) {
 174                                         callback(statusText);
 175                                 }
 176                         }
 177                 };
 178         }
 179 });
 180
 181 // #5280: we need to abort on unload or IE will keep connections alive
 182 jQuery(window).bind( "unload" , function() {
 183
 184         // Abort all pending requests
 185         jQuery.each(xhrs, function(_, xhr) {
 186                 if ( xhr.onreadystatechange ) {
 187                         xhr.onreadystatechange( xhrUnloadAbortMarker );
 188                 }
 189         });
 190
 191         // Resest polling structure to be safe
 192         xhrs = {};
 193
 194 });
 195
 196 })( jQuery );