[625] | 1 | /*! |
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| 2 | * Ext JS Library 3.0.0 |
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| 3 | * Copyright(c) 2006-2009 Ext JS, LLC |
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| 4 | * licensing@extjs.com |
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| 5 | * http://www.extjs.com/license |
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| 6 | */ |
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| 7 | /** |
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| 8 | * @class Ext.data.ScriptTagProxy |
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| 9 | * @extends Ext.data.DataProxy |
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| 10 | * An implementation of Ext.data.DataProxy that reads a data object from a URL which may be in a domain |
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| 11 | * other than the originating domain of the running page.<br> |
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| 12 | * <p> |
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| 13 | * <b>Note that if you are retrieving data from a page that is in a domain that is NOT the same as the originating domain |
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| 14 | * of the running page, you must use this class, rather than HttpProxy.</b><br> |
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| 15 | * <p> |
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| 16 | * The content passed back from a server resource requested by a ScriptTagProxy <b>must</b> be executable JavaScript |
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| 17 | * source code because it is used as the source inside a <script> tag.<br> |
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| 18 | * <p> |
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| 19 | * In order for the browser to process the returned data, the server must wrap the data object |
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| 20 | * with a call to a callback function, the name of which is passed as a parameter by the ScriptTagProxy. |
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| 21 | * Below is a Java example for a servlet which returns data for either a ScriptTagProxy, or an HttpProxy |
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| 22 | * depending on whether the callback name was passed: |
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| 23 | * <p> |
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| 24 | * <pre><code> |
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| 25 | boolean scriptTag = false; |
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| 26 | String cb = request.getParameter("callback"); |
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| 27 | if (cb != null) { |
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| 28 | scriptTag = true; |
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| 29 | response.setContentType("text/javascript"); |
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| 30 | } else { |
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| 31 | response.setContentType("application/x-json"); |
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| 32 | } |
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| 33 | Writer out = response.getWriter(); |
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| 34 | if (scriptTag) { |
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| 35 | out.write(cb + "("); |
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| 36 | } |
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| 37 | out.print(dataBlock.toJsonString()); |
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| 38 | if (scriptTag) { |
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| 39 | out.write(");"); |
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| 40 | } |
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| 41 | </code></pre> |
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| 42 | * |
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| 43 | * @constructor |
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| 44 | * @param {Object} config A configuration object. |
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| 45 | */ |
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| 46 | Ext.data.ScriptTagProxy = function(config){ |
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| 47 | Ext.apply(this, config); |
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| 48 | |
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| 49 | Ext.data.ScriptTagProxy.superclass.constructor.call(this, config); |
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| 50 | |
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| 51 | this.head = document.getElementsByTagName("head")[0]; |
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| 52 | |
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| 53 | /** |
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| 54 | * @event loadexception |
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| 55 | * <b>Deprecated</b> in favor of 'exception' event. |
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| 56 | * Fires if an exception occurs in the Proxy during data loading. This event can be fired for one of two reasons: |
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| 57 | * <ul><li><b>The load call timed out.</b> This means the load callback did not execute within the time limit |
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| 58 | * specified by {@link #timeout}. In this case, this event will be raised and the |
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| 59 | * fourth parameter (read error) will be null.</li> |
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| 60 | * <li><b>The load succeeded but the reader could not read the response.</b> This means the server returned |
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| 61 | * data, but the configured Reader threw an error while reading the data. In this case, this event will be |
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| 62 | * raised and the caught error will be passed along as the fourth parameter of this event.</li></ul> |
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| 63 | * Note that this event is also relayed through {@link Ext.data.Store}, so you can listen for it directly |
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| 64 | * on any Store instance. |
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| 65 | * @param {Object} this |
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| 66 | * @param {Object} options The loading options that were specified (see {@link #load} for details). If the load |
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| 67 | * call timed out, this parameter will be null. |
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| 68 | * @param {Object} arg The callback's arg object passed to the {@link #load} function |
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| 69 | * @param {Error} e The JavaScript Error object caught if the configured Reader could not read the data. |
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| 70 | * If the remote request returns success: false, this parameter will be null. |
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| 71 | */ |
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| 72 | }; |
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| 73 | |
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| 74 | Ext.data.ScriptTagProxy.TRANS_ID = 1000; |
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| 75 | |
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| 76 | Ext.extend(Ext.data.ScriptTagProxy, Ext.data.DataProxy, { |
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| 77 | /** |
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| 78 | * @cfg {String} url The URL from which to request the data object. |
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| 79 | */ |
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| 80 | /** |
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| 81 | * @cfg {Number} timeout (optional) The number of milliseconds to wait for a response. Defaults to 30 seconds. |
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| 82 | */ |
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| 83 | timeout : 30000, |
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| 84 | /** |
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| 85 | * @cfg {String} callbackParam (Optional) The name of the parameter to pass to the server which tells |
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| 86 | * the server the name of the callback function set up by the load call to process the returned data object. |
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| 87 | * Defaults to "callback".<p>The server-side processing must read this parameter value, and generate |
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| 88 | * javascript output which calls this named function passing the data object as its only parameter. |
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| 89 | */ |
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| 90 | callbackParam : "callback", |
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| 91 | /** |
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| 92 | * @cfg {Boolean} nocache (optional) Defaults to true. Disable caching by adding a unique parameter |
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| 93 | * name to the request. |
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| 94 | */ |
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| 95 | nocache : true, |
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| 96 | |
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| 97 | /** |
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| 98 | * HttpProxy implementation of DataProxy#doRequest |
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| 99 | * @param {String} action |
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| 100 | * @param {Ext.data.Record/Ext.data.Record[]} rs If action is <tt>read</tt>, rs will be null |
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| 101 | * @param {Object} params An object containing properties which are to be used as HTTP parameters |
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| 102 | * for the request to the remote server. |
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| 103 | * @param {Ext.data.DataReader} reader The Reader object which converts the data |
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| 104 | * object into a block of Ext.data.Records. |
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| 105 | * @param {Function} callback The function into which to pass the block of Ext.data.Records. |
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| 106 | * The function must be passed <ul> |
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| 107 | * <li>The Record block object</li> |
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| 108 | * <li>The "arg" argument from the load function</li> |
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| 109 | * <li>A boolean success indicator</li> |
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| 110 | * </ul> |
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| 111 | * @param {Object} scope The scope in which to call the callback |
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| 112 | * @param {Object} arg An optional argument which is passed to the callback as its second parameter. |
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| 113 | */ |
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| 114 | doRequest : function(action, rs, params, reader, callback, scope, arg) { |
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| 115 | var p = Ext.urlEncode(Ext.apply(params, this.extraParams)); |
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| 116 | |
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| 117 | var url = this.buildUrl(action, rs); |
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| 118 | if (!url) { |
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| 119 | throw new Ext.data.Api.Error('invalid-url', url); |
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| 120 | } |
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| 121 | url = Ext.urlAppend(url, p); |
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| 122 | |
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| 123 | if(this.nocache){ |
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| 124 | url = Ext.urlAppend(url, '_dc=' + (new Date().getTime())); |
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| 125 | } |
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| 126 | var transId = ++Ext.data.ScriptTagProxy.TRANS_ID; |
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| 127 | var trans = { |
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| 128 | id : transId, |
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| 129 | action: action, |
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| 130 | cb : "stcCallback"+transId, |
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| 131 | scriptId : "stcScript"+transId, |
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| 132 | params : params, |
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| 133 | arg : arg, |
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| 134 | url : url, |
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| 135 | callback : callback, |
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| 136 | scope : scope, |
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| 137 | reader : reader |
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| 138 | }; |
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| 139 | window[trans.cb] = this.createCallback(action, rs, trans); |
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| 140 | url += String.format("&{0}={1}", this.callbackParam, trans.cb); |
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| 141 | if(this.autoAbort !== false){ |
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| 142 | this.abort(); |
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| 143 | } |
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| 144 | |
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| 145 | trans.timeoutId = this.handleFailure.defer(this.timeout, this, [trans]); |
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| 146 | |
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| 147 | var script = document.createElement("script"); |
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| 148 | script.setAttribute("src", url); |
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| 149 | script.setAttribute("type", "text/javascript"); |
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| 150 | script.setAttribute("id", trans.scriptId); |
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| 151 | this.head.appendChild(script); |
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| 152 | |
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| 153 | this.trans = trans; |
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| 154 | }, |
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| 155 | |
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| 156 | // @private createCallback |
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| 157 | createCallback : function(action, rs, trans) { |
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| 158 | var self = this; |
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| 159 | return function(res) { |
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| 160 | self.trans = false; |
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| 161 | self.destroyTrans(trans, true); |
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| 162 | if (action === Ext.data.Api.actions.read) { |
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| 163 | self.onRead.call(self, action, trans, res); |
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| 164 | } else { |
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| 165 | self.onWrite.call(self, action, trans, res, rs); |
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| 166 | } |
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| 167 | }; |
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| 168 | }, |
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| 169 | /** |
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| 170 | * Callback for read actions |
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| 171 | * @param {String} action [Ext.data.Api.actions.create|read|update|destroy] |
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| 172 | * @param {Object} trans The request transaction object |
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| 173 | * @param {Object} res The server response |
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| 174 | * @private |
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| 175 | */ |
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| 176 | onRead : function(action, trans, res) { |
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| 177 | var result; |
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| 178 | try { |
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| 179 | result = trans.reader.readRecords(res); |
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| 180 | }catch(e){ |
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| 181 | // @deprecated: fire loadexception |
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| 182 | this.fireEvent("loadexception", this, trans, res, e); |
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| 183 | |
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| 184 | this.fireEvent('exception', this, 'response', action, trans, res, e); |
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| 185 | trans.callback.call(trans.scope||window, null, trans.arg, false); |
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| 186 | return; |
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| 187 | } |
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| 188 | if (result.success === false) { |
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| 189 | // @deprecated: fire old loadexception for backwards-compat. |
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| 190 | this.fireEvent('loadexception', this, trans, res); |
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| 191 | |
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| 192 | this.fireEvent('exception', this, 'remote', action, trans, res, null); |
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| 193 | } else { |
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| 194 | this.fireEvent("load", this, res, trans.arg); |
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| 195 | } |
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| 196 | trans.callback.call(trans.scope||window, result, trans.arg, result.success); |
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| 197 | }, |
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| 198 | /** |
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| 199 | * Callback for write actions |
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| 200 | * @param {String} action [Ext.data.Api.actions.create|read|update|destroy] |
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| 201 | * @param {Object} trans The request transaction object |
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| 202 | * @param {Object} res The server response |
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| 203 | * @private |
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| 204 | */ |
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| 205 | onWrite : function(action, trans, res, rs) { |
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| 206 | var reader = trans.reader; |
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| 207 | try { |
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| 208 | // though we already have a response object here in STP, run through readResponse to catch any meta-data exceptions. |
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| 209 | reader.readResponse(action, res); |
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| 210 | } catch (e) { |
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| 211 | this.fireEvent('exception', this, 'response', action, trans, res, e); |
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| 212 | trans.callback.call(trans.scope||window, null, res, false); |
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| 213 | return; |
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| 214 | } |
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| 215 | if(!res[reader.meta.successProperty] === true){ |
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| 216 | this.fireEvent('exception', this, 'remote', action, trans, res, rs); |
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| 217 | trans.callback.call(trans.scope||window, null, res, false); |
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| 218 | return; |
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| 219 | } |
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| 220 | this.fireEvent("write", this, action, res[reader.meta.root], res, rs, trans.arg ); |
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| 221 | trans.callback.call(trans.scope||window, res[reader.meta.root], res, true); |
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| 222 | }, |
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| 223 | |
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| 224 | // private |
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| 225 | isLoading : function(){ |
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| 226 | return this.trans ? true : false; |
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| 227 | }, |
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| 228 | |
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| 229 | /** |
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| 230 | * Abort the current server request. |
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| 231 | */ |
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| 232 | abort : function(){ |
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| 233 | if(this.isLoading()){ |
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| 234 | this.destroyTrans(this.trans); |
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| 235 | } |
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| 236 | }, |
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| 237 | |
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| 238 | // private |
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| 239 | destroyTrans : function(trans, isLoaded){ |
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| 240 | this.head.removeChild(document.getElementById(trans.scriptId)); |
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| 241 | clearTimeout(trans.timeoutId); |
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| 242 | if(isLoaded){ |
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| 243 | window[trans.cb] = undefined; |
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| 244 | try{ |
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| 245 | delete window[trans.cb]; |
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| 246 | }catch(e){} |
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| 247 | }else{ |
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| 248 | // if hasn't been loaded, wait for load to remove it to prevent script error |
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| 249 | window[trans.cb] = function(){ |
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| 250 | window[trans.cb] = undefined; |
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| 251 | try{ |
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| 252 | delete window[trans.cb]; |
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| 253 | }catch(e){} |
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| 254 | }; |
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| 255 | } |
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| 256 | }, |
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| 257 | |
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| 258 | // private |
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| 259 | handleFailure : function(trans){ |
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| 260 | this.trans = false; |
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| 261 | this.destroyTrans(trans, false); |
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| 262 | if (trans.action === Ext.data.Api.actions.read) { |
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| 263 | // @deprecated firing loadexception |
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| 264 | this.fireEvent("loadexception", this, null, trans.arg); |
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| 265 | } |
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| 266 | |
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| 267 | this.fireEvent('exception', this, 'response', trans.action, { |
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| 268 | response: null, |
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| 269 | options: trans.arg |
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| 270 | }); |
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| 271 | trans.callback.call(trans.scope||window, null, trans.arg, false); |
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| 272 | }, |
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| 273 | |
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| 274 | // inherit docs |
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| 275 | destroy: function(){ |
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| 276 | this.abort(); |
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| 277 | Ext.data.ScriptTagProxy.superclass.destroy.call(this); |
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| 278 | } |
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| 279 | }); |
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