_source/plugins/ajax/plugin.js

   1 /*
   2 Copyright (c) 2003-2011, CKSource - Frederico Knabben. All rights reserved.
   3 For licensing, see LICENSE.html or http://ckeditor.com/license
   4 */
   5
   6 /**
   7  * @fileOverview Defines the {@link CKEDITOR.ajax} object, which holds ajax methods for
   8  *              data loading.
   9  */
  10
  11 (function()
  12 {
  13         CKEDITOR.plugins.add( 'ajax',
  14                 {
  15                         requires : [ 'xml' ]
  16                 });
  17
  18         /**
  19          * Ajax methods for data loading.
  20          * @namespace
  21          * @example
  22          */
  23         CKEDITOR.ajax = (function()
  24         {
  25                 var createXMLHttpRequest = function()
  26                 {
  27                         // In IE, using the native XMLHttpRequest for local files may throw
  28                         // "Access is Denied" errors.
  29                         if ( !CKEDITOR.env.ie || location.protocol != 'file:' )
  30                                 try { return new XMLHttpRequest(); } catch(e) {}
  31
  32                         try { return new ActiveXObject( 'Msxml2.XMLHTTP' ); } catch (e) {}
  33                         try { return new ActiveXObject( 'Microsoft.XMLHTTP' ); } catch (e) {}
  34
  35                         return null;
  36                 };
  37
  38                 var checkStatus = function( xhr )
  39                 {
  40                         // HTTP Status Codes:
  41                         //       2xx : Success
  42                         //       304 : Not Modified
  43                         //         0 : Returned when running locally (file://)
  44                         //      1223 : IE may change 204 to 1223 (see http://dev.jquery.com/ticket/1450)
  45
  46                         return ( xhr.readyState == 4 &&
  47                                         (       ( xhr.status >= 200 && xhr.status < 300 ) ||
  48                                                 xhr.status == 304 ||
  49                                                 xhr.status === 0 ||
  50                                                 xhr.status == 1223 ) );
  51                 };
  52
  53                 var getResponseText = function( xhr )
  54                 {
  55                         if ( checkStatus( xhr ) )
  56                                 return xhr.responseText;
  57                         return null;
  58                 };
  59
  60                 var getResponseXml = function( xhr )
  61                 {
  62                         if ( checkStatus( xhr ) )
  63                         {
  64                                 var xml = xhr.responseXML;
  65                                 return new CKEDITOR.xml( xml && xml.firstChild ? xml : xhr.responseText );
  66                         }
  67                         return null;
  68                 };
  69
  70                 var load = function( url, callback, getResponseFn )
  71                 {
  72                         var async = !!callback;
  73
  74                         var xhr = createXMLHttpRequest();
  75
  76                         if ( !xhr )
  77                                 return null;
  78
  79                         xhr.open( 'GET', url, async );
  80
  81                         if ( async )
  82                         {
  83                                 // TODO: perform leak checks on this closure.
  84                                 /** @ignore */
  85                                 xhr.onreadystatechange = function()
  86                                 {
  87                                         if ( xhr.readyState == 4 )
  88                                         {
  89                                                 callback( getResponseFn( xhr ) );
  90                                                 xhr = null;
  91                                         }
  92                                 };
  93                         }
  94
  95                         xhr.send(null);
  96
  97                         return async ? '' : getResponseFn( xhr );
  98                 };
  99
 100                 return  /** @lends CKEDITOR.ajax */ {
 101
 102                         /**
 103                          * Loads data from an URL as plain text.
 104                          * @param {String} url The URL from which load data.
 105                          * @param {Function} [callback] A callback function to be called on
 106                          *              data load. If not provided, the data will be loaded
 107                          *              synchronously.
 108                          * @returns {String} The loaded data. For asynchronous requests, an
 109                          *              empty string. For invalid requests, null.
 110                          * @example
 111                          * // Load data synchronously.
 112                          * var data = CKEDITOR.ajax.load( 'somedata.txt' );
 113                          * alert( data );
 114                          * @example
 115                          * // Load data asynchronously.
 116                          * var data = CKEDITOR.ajax.load( 'somedata.txt', function( data )
 117                          *     {
 118                          *         alert( data );
 119                          *     } );
 120                          */
 121                         load : function( url, callback )
 122                         {
 123                                 return load( url, callback, getResponseText );
 124                         },
 125
 126                         /**
 127                          * Loads data from an URL as XML.
 128                          * @param {String} url The URL from which load data.
 129                          * @param {Function} [callback] A callback function to be called on
 130                          *              data load. If not provided, the data will be loaded
 131                          *              synchronously.
 132                          * @returns {CKEDITOR.xml} An XML object holding the loaded data. For asynchronous requests, an
 133                          *              empty string. For invalid requests, null.
 134                          * @example
 135                          * // Load XML synchronously.
 136                          * var xml = CKEDITOR.ajax.loadXml( 'somedata.xml' );
 137                          * alert( xml.getInnerXml( '//' ) );
 138                          * @example
 139                          * // Load XML asynchronously.
 140                          * var data = CKEDITOR.ajax.loadXml( 'somedata.xml', function( xml )
 141                          *     {
 142                          *         alert( xml.getInnerXml( '//' ) );
 143                          *     } );
 144                          */
 145                         loadXml : function( url, callback )
 146                         {
 147                                 return load( url, callback, getResponseXml );
 148                         }
 149                 };
 150         })();
 151
 152 })();