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                                 // #5280: we need to abort on unload or IE will keep connections alive
  28                                 if ( ! xhrUnloadAbortMarker ) {
  29
  30                                         xhrUnloadAbortMarker = [];
  31
  32                                         jQuery(window).bind( "unload" , function() {
  33
  34                                                 // Abort all pending requests
  35                                                 jQuery.each(xhrs, function(_, xhr) {
  36                                                         if ( xhr.onreadystatechange ) {
  37                                                                 xhr.onreadystatechange( xhrUnloadAbortMarker );
  38                                                         }
  39                                                 });
  40
  41                                                 // Reset polling structure to be safe
  42                                                 xhrs = {};
  43
  44                                         });
  45                                 }
  46
  47                                 var xhr = xhrPool.pop() || s.xhr(),
  48                                         handle;
  49
  50                                 // Open the socket
  51                                 // Passing null username, generates a login popup on Opera (#2865)
  52                                 if ( s.username ) {
  53                                         xhr.open(s.type, s.url, s.async, s.username, s.password);
  54                                 } else {
  55                                         xhr.open(s.type, s.url, s.async);
  56                                 }
  57
  58                                 // Requested-With header
  59                                 // Not set for crossDomain requests with no content
  60                                 // (see why at http://trac.dojotoolkit.org/ticket/9486)
  61                                 // Won't change header if already provided in beforeSend
  62                                 if ( ! ( s.crossDomain && ! s.hasContent ) && ! headers["x-requested-with"] ) {
  63                                         headers["x-requested-with"] = "XMLHttpRequest";
  64                                 }
  65
  66                                 // Need an extra try/catch for cross domain requests in Firefox 3
  67                                 try {
  68
  69                                         jQuery.each(headers, function(key,value) {
  70                                                 xhr.setRequestHeader(key,value);
  71                                         });
  72
  73                                 } catch(_) {}
  74
  75                                 // Do send the request
  76                                 try {
  77                                         xhr.send( ( s.hasContent && s.data ) || null );
  78                                 } catch(e) {
  79                                         // Store back in pool
  80                                         xhrPool.push( xhr );
  81                                         complete(0, "error", "" + e);
  82                                         return;
  83                                 }
  84
  85                                 // Listener
  86                                 callback = function ( abortStatusText ) {
  87
  88                                         // Was never called and is aborted or complete
  89                                         if ( callback && ( abortStatusText || xhr.readyState === 4 ) ) {
  90
  91                                                 // Do not listen anymore
  92                                                 // and Store back in pool
  93                                                 if (handle) {
  94                                                         xhr.onreadystatechange = jQuery.noop;
  95                                                         delete xhrs[ handle ];
  96                                                         handle = undefined;
  97                                                         xhrPool.push( xhr );
  98                                                 }
  99
 100                                                 callback = 0;
 101
 102                                                 // Get info
 103                                                 var status, statusText, response, responseHeaders;
 104
 105                                                 if ( abortStatusText ) {
 106
 107                                                         if ( xhr.readyState !== 4 ) {
 108                                                                 xhr.abort();
 109                                                         }
 110
 111                                                         // Stop here if unloadAbort
 112                                                         if ( abortStatusText === xhrUnloadAbortMarker ) {
 113                                                                 return;
 114                                                         }
 115
 116                                                         status = 0;
 117                                                         statusText = abortStatusText;
 118
 119                                                 } else {
 120
 121                                                         status = xhr.status;
 122
 123                                                         try { // Firefox throws an exception when accessing statusText for faulty cross-domain requests
 124
 125                                                                 statusText = xhr.statusText;
 126
 127                                                         } catch( e ) {
 128
 129                                                                 statusText = ""; // We normalize with Webkit giving an empty statusText
 130
 131                                                         }
 132
 133                                                         responseHeaders = xhr.getAllResponseHeaders();
 134
 135                                                         // Filter status for non standard behaviours
 136                                                         // (so many they seem to be the actual "standard")
 137                                                         status =
 138                                                                 // Opera returns 0 when it should be 304
 139                                                                 // Webkit returns 0 for failing cross-domain no matter the real status
 140                                                                 status === 0 ?
 141                                                                         (
 142                                                                                 ! s.crossDomain || statusText ? // Webkit, Firefox: filter out faulty cross-domain requests
 143                                                                                 (
 144                                                                                         responseHeaders ? // Opera: filter out real aborts #6060
 145                                                                                         304
 146                                                                                         :
 147                                                                                         0
 148                                                                                 )
 149                                                                                 :
 150                                                                                 302 // We assume 302 but could be anything cross-domain related
 151                                                                         )
 152                                                                         :
 153                                                                         (
 154                                                                                 status == 1223 ?        // IE sometimes returns 1223 when it should be 204 (see #1450)
 155                                                                                         204
 156                                                                                         :
 157                                                                                         status
 158                                                                         );
 159
 160                                                         // Guess response & update dataType accordingly
 161                                                         response =
 162                                                                 determineDataType(
 163                                                                         s,
 164                                                                         xhr.getResponseHeader("content-type"),
 165                                                                         xhr.responseText,
 166                                                                         xhr.responseXML );
 167                                                 }
 168
 169                                                 // Call complete
 170                                                 complete(status,statusText,response,responseHeaders);
 171                                         }
 172                                 };
 173
 174                                 // if we're in sync mode
 175                                 // or it's in cache and has been retrieved directly (IE6 & IE7)
 176                                 // we need to manually fire the callback
 177                                 if ( ! s.async || xhr.readyState === 4 ) {
 178
 179                                         callback();
 180
 181                                 } else {
 182
 183                                         // Listener is externalized to handle abort on unload
 184                                         handle = xhrPollingId++;
 185                                         xhrs[ handle ] = xhr;
 186                                         xhr.onreadystatechange = function() {
 187                                                 callback();
 188                                         };
 189                                 }
 190                         },
 191
 192                         abort: function(statusText) {
 193                                 if ( callback ) {
 194                                         callback(statusText);
 195                                 }
 196                         }
 197                 };
 198         }
 199 });
 200
 201 })( jQuery );