2 Copyright (c) 2009, Yahoo! Inc. All rights reserved.
3 Code licensed under the BSD License:
4 http://developer.yahoo.net/yui/license.txt
8 YUI.add('datasource-local', function(Y) {
11 * The DataSource utility provides a common configurable interface for widgets to
12 * access a variety of data, from JavaScript arrays to online database servers.
18 * Provides the base DataSource implementation, which can be extended to
19 * create DataSources for specific data protocols, such as the IO Utility, the
20 * Get Utility, or custom functions.
23 * @submodule datasource-local
27 * Base class for the DataSource Utility.
28 * @class DataSource.Local
34 DSLocal = function() {
35 DSLocal.superclass.constructor.apply(this, arguments);
38 /////////////////////////////////////////////////////////////////////////////
40 // DataSource static properties
42 /////////////////////////////////////////////////////////////////////////////
51 * @value "dataSourceLocal"
53 NAME: "dataSourceLocal",
55 /////////////////////////////////////////////////////////////////////////////
57 // DataSource Attributes
59 /////////////////////////////////////////////////////////////////////////////
64 * @description Pointer to live data.
74 * Global transaction counter.
76 * @property DataSource._tId
85 * Executes a given callback. The third param determines whether to execute
87 * @method DataSource.issueCallback
88 * @param callback {Object} The callback object.
89 * @param params {Array} params to be passed to the callback method
90 * @param error {Boolean} whether an error occurred
93 issueCallback: function (e) {
95 var callbackFunc = (e.error && e.callback.failure) || e.callback.success;
103 Y.extend(DSLocal, Y.Base, {
105 * Internal init() handler.
107 * @method initializer
108 * @param config {Object} Config object.
111 initializer: function(config) {
116 * This method creates all the events for this module.
117 * @method _initEvents
120 _initEvents: function() {
122 * Fired when a data request is received.
125 * @param e {Event.Facade} Event Facade with the following properties:
127 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
128 * <dt>request (Object)</dt> <dd>The request.</dd>
129 * <dt>callback (Object)</dt> <dd>The callback object.</dd>
130 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
132 * @preventable _defRequestFn
134 this.publish("request", {defaultFn: Y.bind("_defRequestFn", this), queuable:true});
137 * Fired when raw data is received.
140 * @param e {Event.Facade} Event Facade with the following properties:
142 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
143 * <dt>request (Object)</dt> <dd>The request.</dd>
144 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
146 * <dt>success (Function)</dt> <dd>Success handler.</dd>
147 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
150 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
151 * <dt>data (Object)</dt> <dd>Raw data.</dd>
153 * @preventable _defDataFn
155 this.publish("data", {defaultFn: Y.bind("_defDataFn", this), queuable:true});
158 * Fired when response is returned.
161 * @param e {Event.Facade} Event Facade with the following properties:
163 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
164 * <dt>request (Object)</dt> <dd>The request.</dd>
165 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
167 * <dt>success (Function)</dt> <dd>Success handler.</dd>
168 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
171 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
172 * <dt>data (Object)</dt> <dd>Raw data.</dd>
173 * <dt>response (Object)</dt> <dd>Normalized response object with the following properties:
175 * <dt>results (Object)</dt> <dd>Parsed results.</dd>
176 * <dt>meta (Object)</dt> <dd>Parsed meta data.</dd>
177 * <dt>error (Boolean)</dt> <dd>Error flag.</dd>
181 * @preventable _defResponseFn
183 this.publish("response", {defaultFn: Y.bind("_defResponseFn", this), queuable:true});
186 * Fired when an error is encountered.
189 * @param e {Event.Facade} Event Facade with the following properties:
191 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
192 * <dt>request (Object)</dt> <dd>The request.</dd>
193 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
195 * <dt>success (Function)</dt> <dd>Success handler.</dd>
196 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
199 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
200 * <dt>data (Object)</dt> <dd>Raw data.</dd>
201 * <dt>response (Object)</dt> <dd>Normalized response object with the following properties:
203 * <dt>results (Object)</dt> <dd>Parsed results.</dd>
204 * <dt>meta (Object)</dt> <dd>Parsed meta data.</dd>
205 * <dt>error (Object)</dt> <dd>Error object.</dd>
214 * Manages request/response transaction. Must fire <code>response</code>
215 * event when response is received. This method should be implemented by
216 * subclasses to achieve more complex behavior such as accessing remote data.
218 * @method _defRequestFn
219 * @param e {Event.Facade} Event Facadewith the following properties:
221 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
222 * <dt>request (Object)</dt> <dd>The request.</dd>
223 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
225 * <dt>success (Function)</dt> <dd>Success handler.</dd>
226 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
229 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
233 _defRequestFn: function(e) {
234 var data = this.get("source");
237 if(LANG.isUndefined(data)) {
238 e.error = new Error("Local source undefined");
241 this.fire("error", e);
244 this.fire("data", Y.mix({data:data}, e));
248 * Normalizes raw data into a response that includes results and meta properties.
251 * @param e {Event.Facade} Event Facade with the following properties:
253 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
254 * <dt>request (Object)</dt> <dd>The request.</dd>
255 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
257 * <dt>success (Function)</dt> <dd>Success handler.</dd>
258 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
261 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
262 * <dt>data (Object)</dt> <dd>Raw data.</dd>
266 _defDataFn: function(e) {
270 results: (LANG.isArray(data)) ? data : [data],
271 meta: (meta) ? meta : {}
274 this.fire("response", Y.mix({response: response}, e));
278 * Sends data as a normalized response to callback.
280 * @method _defResponseFn
281 * @param e {Event.Facade} Event Facade with the following properties:
283 * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
284 * <dt>request (Object)</dt> <dd>The request.</dd>
285 * <dt>callback (Object)</dt> <dd>The callback object with the following properties:
287 * <dt>success (Function)</dt> <dd>Success handler.</dd>
288 * <dt>failure (Function)</dt> <dd>Failure handler.</dd>
291 * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
292 * <dt>data (Object)</dt> <dd>Raw data.</dd>
293 * <dt>response (Object)</dt> <dd>Normalized response object with the following properties:
295 * <dt>results (Object)</dt> <dd>Parsed results.</dd>
296 * <dt>meta (Object)</dt> <dd>Parsed meta data.</dd>
297 * <dt>error (Boolean)</dt> <dd>Error flag.</dd>
303 _defResponseFn: function(e) {
304 // Send the response back to the callback
305 DSLocal.issueCallback(e);
309 * Generates a unique transaction ID and fires <code>request</code> event.
311 * @method sendRequest
312 * @param request {Object} Request.
313 * @param callback {Object} An object literal with the following properties:
315 * <dt><code>success</code></dt>
316 * <dd>The function to call when the data is ready.</dd>
317 * <dt><code>failure</code></dt>
318 * <dd>The function to call upon a response failure condition.</dd>
319 * <dt><code>argument</code></dt>
320 * <dd>Arbitrary data payload that will be passed back to the success and failure handlers.</dd>
322 * @param cfg {Object} Configuration object
323 * @return {Number} Transaction ID.
325 sendRequest: function(request, callback, cfg) {
326 var tId = DSLocal._tId++;
327 this.fire("request", {tId:tId, request:request, callback:callback, cfg:cfg || {}});
332 Y.namespace("DataSource").Local = DSLocal;
336 }, '3.0.0' ,{requires:['base']});