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JavaScript

data-foundation-debug.js：源码内容

*/
destroy: function(){
this.purgeListeners();
}
});
/**
* @class Ext.data.DataProxy.Error
* @extends Ext.Error
* DataProxy Error extension.
* constructor
* @param {String} name
* @param {Record/Array[Record]/Array}
*/
Ext.data.DataProxy.Error = Ext.extend(Ext.Error, {
constructor : function(message, arg) {
this.arg = arg;
Ext.Error.call(this, message);
},
name: 'Ext.data.DataProxy'
});
Ext.apply(Ext.data.DataProxy.Error.prototype, {
lang: {
'action-undefined': "DataProxy attempted to execute an API-action but found an undefined url / function. Please review your Proxy url/api-configuration.",
'api-invalid': 'Recieved an invalid API-configuration. Please ensure your proxy API-configuration contains only the actions from Ext.data.Api.actions.'
}
});
/**
* @class Ext.data.ScriptTagProxy
* @extends Ext.data.DataProxy
* An implementation of Ext.data.DataProxy that reads a data object from a URL which may be in a domain
* other than the originating domain of the running page.
*
* Note that if you are retrieving data from a page that is in a domain that is NOT the same as the originating domain
* of the running page, you must use this class, rather than HttpProxy.
*
* The content passed back from a server resource requested by a ScriptTagProxy must be executable JavaScript
* source code because it is used as the source inside a <script> tag.
*
* In order for the browser to process the returned data, the server must wrap the data object
* with a call to a callback function, the name of which is passed as a parameter by the ScriptTagProxy.
* Below is a Java example for a servlet which returns data for either a ScriptTagProxy, or an HttpProxy
* depending on whether the callback name was passed:
*
* <pre><code>
boolean scriptTag = false;
String cb = request.getParameter("callback");
if (cb != null) {
scriptTag = true;
response.setContentType("text/javascript");
} else {
response.setContentType("application/x-json");
}
Writer out = response.getWriter();
if (scriptTag) {
out.write(cb + "(");
}
out.print(dataBlock.toJsonString());
if (scriptTag) {
out.write(");");
}
</code></pre>
*
* @constructor
* @param {Object} config A configuration object.
*/
Ext.data.ScriptTagProxy = function(config){
Ext.apply(this, config);
Ext.data.ScriptTagProxy.superclass.constructor.call(this, config);
this.head = document.getElementsByTagName("head")[0];
/**
* @event loadexception
* Deprecated in favor of 'exception' event.
* Fires if an exception occurs in the Proxy during data loading. This event can be fired for one of two reasons:
* <ul><li>The load call timed out. This means the load callback did not execute within the time limit
* specified by {@link #timeout}. In this case, this event will be raised and the
* fourth parameter (read error) will be null.</li>
* <li>The load succeeded but the reader could not read the response. This means the server returned
* data, but the configured Reader threw an error while reading the data. In this case, this event will be
* raised and the caught error will be passed along as the fourth parameter of this event.</li></ul>
* Note that this event is also relayed through {@link Ext.data.Store}, so you can listen for it directly
* on any Store instance.
* @param {Object} this
* @param {Object} options The loading options that were specified (see {@link #load} for details). If the load
* call timed out, this parameter will be null.
* @param {Object} arg The callback's arg object passed to the {@link #load} function
* @param {Error} e The JavaScript Error object caught if the configured Reader could not read the data.
* If the remote request returns success: false, this parameter will be null.
*/
};
Ext.data.ScriptTagProxy.TRANS_ID = 1000;
Ext.extend(Ext.data.ScriptTagProxy, Ext.data.DataProxy, {
/**
* @cfg {String} url The URL from which to request the data object.
*/
/**
* @cfg {Number} timeout (optional) The number of milliseconds to wait for a response. Defaults to 30 seconds.
*/
timeout : 30000,
/**
* @cfg {String} callbackParam (Optional) The name of the parameter to pass to the server which tells
* the server the name of the callback function set up by the load call to process the returned data object.
* Defaults to "callback".The server-side processing must read this parameter value, and generate
* javascript output which calls this named function passing the data object as its only parameter.
*/
callbackParam : "callback",
/**
* @cfg {Boolean} nocache (optional) Defaults to true. Disable caching by adding a unique parameter
* name to the request.
*/
nocache : true,
/**
* HttpProxy implementation of DataProxy#doRequest
* @param {String} action
* @param {Ext.data.Record/Ext.data.Record[]} rs If action is <tt>read</tt>, rs will be null
* @param {Object} params An object containing properties which are to be used as HTTP parameters
* for the request to the remote server.
* @param {Ext.data.DataReader} reader The Reader object which converts the data
* object into a block of Ext.data.Records.
* @param {Function} callback The function into which to pass the block of Ext.data.Records.
* The function must be passed <ul>
* <li>The Record block object</li>
* <li>The "arg" argument from the load function</li>
* <li>A boolean success indicator</li>
* </ul>
* @param {Object} scope The scope in which to call the callback
* @param {Object} arg An optional argument which is passed to the callback as its second parameter.
*/
doRequest : function(action, rs, params, reader, callback, scope, arg) {
var p = Ext.urlEncode(Ext.apply(params, this.extraParams));
var url = this.buildUrl(action, rs);
if (!url) {
throw new Ext.data.Api.Error('invalid-url', url);
}
url = Ext.urlAppend(url, p);
if(this.nocache){
url = Ext.urlAppend(url, '_dc=' + (new Date().getTime()));
}
var transId = ++Ext.data.ScriptTagProxy.TRANS_ID;
var trans = {
id : transId,
action: action,
cb : "stcCallback"+transId,
scriptId : "stcScript"+transId,
params : params,
arg : arg,
url : url,
callback : callback,
scope : scope,
reader : reader
};
window[trans.cb] = this.createCallback(action, rs, trans);
url += String.format("&{0}={1}", this.callbackParam, trans.cb);
if(this.autoAbort !== false){
this.abort();
}
trans.timeoutId = this.handleFailure.defer(this.timeout, this, [trans]);
var script = document.createElement("script");
script.setAttribute("src", url);
script.setAttribute("type", "text/javascript");
script.setAttribute("id", trans.scriptId);
this.head.appendChild(script);
this.trans = trans;
},
// @private createCallback
createCallback : function(action, rs, trans) {
var self = this;
return function(res) {
self.trans = false;
self.destroyTrans(trans, true);
if (action === Ext.data.Api.actions.read) {
self.onRead.call(self, action, trans, res);
} else {
self.onWrite.call(self, action, trans, res, rs);
}
};
},
/**
* Callback for read actions
* @param {String} action [Ext.data.Api.actions.create|read|update|destroy]
* @param {Object} trans The request transaction object
* @param {Object} res The server response
* @private
*/
onRead : function(action, trans, res) {
var result;
try {
result = trans.reader.readRecords(res);
}catch(e){
// @deprecated: fire loadexception
this.fireEvent("loadexception", this, trans, res, e);
this.fireEvent('exception', this, 'response', action, trans, res, e);
trans.callback.call(trans.scope||window, null, trans.arg, false);
return;
}
if (result.success === false) {
// @deprecated: fire old loadexception for backwards-compat.
this.fireEvent('loadexception', this, trans, res);
this.fireEvent('exception', this, 'remote', action, trans, res, null);
} else {
this.fireEvent("load", this, res, trans.arg);
}
trans.callback.call(trans.scope||window, result, trans.arg, result.success);
},
/**
* Callback for write actions
* @param {String} action [Ext.data.Api.actions.create|read|update|destroy]
* @param {Object} trans The request transaction object
* @param {Object} res The server response
* @private
*/
onWrite : function(action, trans, res, rs) {
var reader = trans.reader;
try {
// though we already have a response object here in STP, run through readResponse to catch any meta-data exceptions.
reader.readResponse(action, res);
} catch (e) {
this.fireEvent('exception', this, 'response', action, trans, res, e);
trans.callback.call(trans.scope||window, null, res, false);
return;
}
if(!res[reader.meta.successProperty] === true){
this.fireEvent('exception', this, 'remote', action, trans, res, rs);
trans.callback.call(trans.scope||window, null, res, false);
return;
}
this.fireEvent("write", this, action, res[reader.meta.root], res, rs, trans.arg );
trans.callback.call(trans.scope||window, res[reader.meta.root], res, true);
},
// private
isLoading : function(){
return this.trans ? true : false;
},
/**
* Abort the current server request.
*/
abort : function(){
if(this.isLoading()){
this.destroyTrans(this.trans);
}
},
// private
destroyTrans : function(trans, isLoaded){
this.head.removeChild(document.getElementById(trans.scriptId));
clearTimeout(trans.timeoutId);
if(isLoaded){
window[trans.cb] = undefined;
try{
delete window[trans.cb];
}catch(e){}
}else{
// if hasn't been loaded, wait for load to remove it to prevent script error
window[trans.cb] = function(){
window[trans.cb] = undefined;
try{
delete window[trans.cb];
}catch(e){}
};
}
},
// private
handleFailure : function(trans){
this.trans = false;
this.destroyTrans(trans, false);
if (trans.action === Ext.data.Api.actions.read) {
// @deprecated firing loadexception
this.fireEvent("loadexception", this, null, trans.arg);
}
this.fireEvent('exception', this, 'response', trans.action, {
response: null,
options: trans.arg
});
trans.callback.call(trans.scope||window, null, trans.arg, false);
},
// inherit docs
destroy: function(){
this.abort();
Ext.data.ScriptTagProxy.superclass.destroy.call(this);
}
});/**
* @class Ext.data.HttpProxy
* @extends Ext.data.DataProxy
* An implementation of {@link Ext.data.DataProxy} that processes data requests within the same
* domain of the originating page.
* Note: this class cannot be used to retrieve data from a domain other
* than the domain from which the running page was served. For cross-domain requests, use a
* {@link Ext.data.ScriptTagProxy ScriptTagProxy}.
* Be aware that to enable the browser to parse an XML document, the server must set
* the Content-Type header in the HTTP response to "<tt>text/xml</tt>".
* @constructor
* @param {Object} conn
* An {@link Ext.data.Connection} object, or options parameter to {@link Ext.Ajax#request}.
* Note that if this HttpProxy is being used by a (@link Ext.data.Store Store}, then the
* Store's call to {@link #load} will override any specified <tt>callback</tt> and <tt>params</tt>
* options. In this case, use the Store's {@link Ext.data.Store#events events} to modify parameters,
* or react to loading events. The Store's {@link Ext.data.Store#baseParams baseParams} may also be
* used to pass parameters known at instantiation time.
* If an options parameter is passed, the singleton {@link Ext.Ajax} object will be used to make
* the request.
*/
Ext.data.HttpProxy = function(conn){
Ext.data.HttpProxy.superclass.constructor.call(this, conn);
/**
* The Connection object (Or options parameter to {@link Ext.Ajax#request}) which this HttpProxy
* uses to make requests to the server. Properties of this object may be changed dynamically to
* change the way data is requested.
* @property
*/
this.conn = conn;
// nullify the connection url. The url param has been copied to 'this' above. The connection
// url will be set during each execution of doRequest when buildUrl is called. This makes it easier for users to override the
// connection url during beforeaction events (ie: beforeload, beforesave, etc). The connection url will be nullified
// after each request as well. Url is always re-defined during doRequest.
this.conn.url = null;
this.useAjax = !conn || !conn.events;
//private. A hash containing active requests, keyed on action [Ext.data.Api.actions.create|read|update|destroy]
var actions = Ext.data.Api.actions;
this.activeRequest = {};
for (var verb in actions) {
this.activeRequest[actions[verb]] = undefined;
}
};
Ext.extend(Ext.data.HttpProxy, Ext.data.DataProxy, {
/**
* @cfg {Boolean} restful
* If set to <tt>true</tt>, a {@link Ext.data.Record#phantom non-phantom} record's
* {@link Ext.data.Record#id id} will be appended to the url (defaults to <tt>false</tt>).
* The url is built based upon the action being executed <tt>[load|create|save|destroy]</tt>
* using the commensurate <tt>{@link #api}</tt> property, or if undefined default to the
* configured {@link Ext.data.Store}.{@link Ext.data.Store#url url}.
* Some MVC (e.g., Ruby on Rails, Merb and Django) support this style of segment based urls
* where the segments in the URL follow the Model-View-Controller approach.<pre><code>
* someSite.com/controller/action/id
* </code></pre>
* Where the segments in the url are typically:<div class="mdetail-params"><ul>
* <li>The first segment : represents the controller class that should be invoked.</li>
* <li>The second segment : represents the class function, or method, that should be called.</li>
* <li>The third segment : represents the ID (a variable typically passed to the method).</li>
* </ul></div>
* For example:
* <pre><code>
api: {
load : '/controller/load',
create : '/controller/new', // Server MUST return idProperty of new record
save : '/controller/update',
destroy : '/controller/destroy_action'
}
// Alternatively, one can use the object-form to specify each API-action
api: {
load: {url: 'read.php', method: 'GET'},
create: 'create.php',
destroy: 'destroy.php',
save: 'update.php'
}
*/
/**
* Return the {@link Ext.data.Connection} object being used by this Proxy.
* @return {Connection} The Connection object. This object may be used to subscribe to events on
* a finer-grained basis than the DataProxy events.
*/
getConnection : function() {
return this.useAjax ? Ext.Ajax : this.conn;
},
/**
* Used for overriding the url used for a single request. Designed to be called during a beforeaction event. Calling setUrl
* will override any urls set via the api configuration parameter. Set the optional parameter makePermanent to set the url for
* all subsequent requests. If not set to makePermanent, the next request will use the same url or api configuration defined
* in the initial proxy configuration.
* @param {String} url
* @param {Boolean} makePermanent (Optional) [false]
*
* (e.g.: beforeload, beforesave, etc).
*/
setUrl : function(url, makePermanent) {
this.conn.url = url;
if (makePermanent === true) {
this.url = url;
Ext.data.Api.prepare(this);
}
},
/**
* HttpProxy implementation of DataProxy#doRequest
* @param {String} action The crud action type (create, read, update, destroy)
* @param {Ext.data.Record/Ext.data.Record[]} rs If action is load, rs will be null
* @param {Object} params An object containing properties which are to be used as HTTP parameters
* for the request to the remote server.
* @param {Ext.data.DataReader} reader The Reader object which converts the data
* object into a block of Ext.data.Records.
* @param {Function} callback
* <div class="sub-desc">A function to be called after the request.
* The <tt>callback</tt> is passed the following arguments:<ul>
* <li><tt>r</tt> : Ext.data.Record[] The block of Ext.data.Records.</li>
* <li><tt>options</tt>: Options object from the action request</li>
* <li><tt>success</tt>: Boolean success indicator</li></ul></div>
* @param {Object} scope The scope in which to call the callback
* @param {Object} arg An optional argument which is passed to the callback as its second parameter.
*/
doRequest : function(action, rs, params, reader, cb, scope, arg) {
var o = {
method: (this.api[action]) ? this.api[action]['method'] : undefined,
request: {
callback : cb,
scope : scope,
arg : arg
},
reader: reader,
callback : this.createCallback(action, rs),
scope: this
};
// Sample the request data: If it's an object, then it hasn't been json-encoded yet.
// Transmit data using jsonData config of Ext.Ajax.request
if (typeof(params[reader.meta.root]) === 'object') {
o.jsonData = params;
} else {
o.params = params || {};
}
// Set the connection url. If this.conn.url is not null here,
// the user may have overridden the url during a beforeaction event-handler.
// this.conn.url is nullified after each request.
if (this.conn.url === null) {
this.conn.url = this.buildUrl(action, rs);
}
else if (this.restful === true && rs instanceof Ext.data.Record && !rs.phantom) {
this.conn.url += '/' + rs.id;
}
if(this.useAjax){
Ext.applyIf(o, this.conn);
// If a currently running request is found for this action, abort it.
if (this.activeRequest[action]) {
// Disabled aborting activeRequest while implementing REST. activeRequest[action] will have to become an array
//Ext.Ajax.abort(this.activeRequest[action]);
}
this.activeRequest[action] = Ext.Ajax.request(o);
}else{
this.conn.request(o);
}
// request is sent, nullify the connection url in preparation for the next request
this.conn.url = null;
},
/**
* Returns a callback function for a request. Note a special case is made for the
* read action vs all the others.
* @param {String} action [create|update|delete|load]
* @param {Ext.data.Record[]} rs The Store-recordset being acted upon
* @private
*/
createCallback : function(action, rs) {
return function(o, success, response) {
this.activeRequest[action] = undefined;
if (!success) {
if (action === Ext.data.Api.actions.read) {
// @deprecated: fire loadexception for backwards compat.
this.fireEvent('loadexception', this, o, response);
}
this.fireEvent('exception', this, 'response', action, o, response);
o.request.callback.call(o.request.scope, null, o.request.arg, false);
return;
}
if (action === Ext.data.Api.actions.read) {
this.onRead(action, o, response);
} else {
this.onWrite(action, o, response, rs);
}
}
},
/**
* Callback for read action
* @param {String} action Action name as per {@link Ext.data.Api.actions#read}.
* @param {Object} o The request transaction object
* @param {Object} res The server response
* @private
*/
onRead : function(action, o, response) {
var result;
try {
result = o.reader.read(response);
}catch(e){
// @deprecated: fire old loadexception for backwards-compat.
this.fireEvent('loadexception', this, o, response, e);
this.fireEvent('exception', this, 'response', action, o, response, e);
o.request.callback.call(o.request.scope, null, o.request.arg, false);
return;
}
if (result.success === false) {
// @deprecated: fire old loadexception for backwards-compat.
this.fireEvent('loadexception', this, o, response);
// Get DataReader read-back a response-object to pass along to exception event
var res = o.reader.readResponse(action, response);
this.fireEvent('exception', this, 'remote', action, o, res, null);
}
else {
this.fireEvent('load', this, o, o.request.arg);
}
o.request.callback.call(o.request.scope, result, o.request.arg, result.success);
},
/**
* Callback for write actions
* @param {String} action [Ext.data.Api.actions.create|read|update|destroy]
* @param {Object} trans The request transaction object
* @param {Object} res The server response
* @private
*/
onWrite : function(action, o, response, rs) {
var reader = o.reader;
var res;
try {
res = reader.readResponse(action, response);
} catch (e) {
this.fireEvent('exception', this, 'response', action, o, response, e);
o.request.callback.call(o.request.scope, null, o.request.arg, false);
return;
}
if (res[reader.meta.successProperty] === false) {
this.fireEvent('exception', this, 'remote', action, o, res, rs);
} else {
this.fireEvent('write', this, action, res[reader.meta.root], res, rs, o.request.arg);
}
o.request.callback.call(o.request.scope, res[reader.meta.root], res, res[reader.meta.successProperty]);
},
// inherit docs
destroy: function(){
if(!this.useAjax){
this.conn.abort();
}else if(this.activeRequest){
var actions = Ext.data.Api.actions;
for (var verb in actions) {
if(this.activeRequest[actions[verb]]){
Ext.Ajax.abort(this.activeRequest[actions[verb]]);
}
}
}
Ext.data.HttpProxy.superclass.destroy.call(this);
}
});/**
* @class Ext.data.MemoryProxy
* @extends Ext.data.DataProxy
* An implementation of Ext.data.DataProxy that simply passes the data specified in its constructor
* to the Reader when its load method is called.
* @constructor
* @param {Object} data The data object which the Reader uses to construct a block of Ext.data.Records.
*/
Ext.data.MemoryProxy = function(data){
// Must define a dummy api with "read" action to satisfy DataProxy#doRequest and Ext.data.Api#prepare *before* calling super
var api = {};
api[Ext.data.Api.actions.read] = true;
Ext.data.MemoryProxy.superclass.constructor.call(this, {
api: api
});
this.data = data;
};
Ext.extend(Ext.data.MemoryProxy, Ext.data.DataProxy, {
/**
* @event loadexception
* Fires if an exception occurs in the Proxy during data loading. Note that this event is also relayed
* through {@link Ext.data.Store}, so you can listen for it directly on any Store instance.
* @param {Object} this
* @param {Object} arg The callback's arg object passed to the {@link #load} function
* @param {Object} null This parameter does not apply and will always be null for MemoryProxy
* @param {Error} e The JavaScript Error object caught if the configured Reader could not read the data
*/
/**
* MemoryProxy implementation of DataProxy#doRequest
* @param {String} action
* @param {Ext.data.Record/Ext.data.Record[]} rs If action is load, rs will be null
* @param {Object} params An object containing properties which are to be used as HTTP parameters
* for the request to the remote server.
* @param {Ext.data.DataReader} reader The Reader object which converts the data
* object into a block of Ext.data.Records.
* @param {Function} callback The function into which to pass the block of Ext.data.Records.
* The function must be passed <ul>
* <li>The Record block object</li>
* <li>The "arg" argument from the load function</li>
* <li>A boolean success indicator</li>
* </ul>
* @param {Object} scope The scope in which to call the callback
* @param {Object} arg An optional argument which is passed to the callback as its second parameter.
*/
doRequest : function(action, rs, params, reader, callback, scope, arg) {
// No implementation for CRUD in MemoryProxy. Assumes all actions are 'load'
params = params || {};
var result;
try {
result = reader.readRecords(this.data);
}catch(e){
// @deprecated loadexception
this.fireEvent("loadexception", this, null, arg, e);
this.fireEvent('exception', this, 'response', action, arg, null, e);
callback.call(scope, null, arg, false);
return;
}
callback.call(scope, result, arg, true);
}
});