/*
Copyright (c) 2010, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.com/yui/license.html
version: 3.3.0
build: 3167
*/
YUI.add('datasource-local', function(Y) {
/**
* The DataSource utility provides a common configurable interface for widgets to
* access a variety of data, from JavaScript arrays to online database servers.
*
* @module datasource
*/
/**
* Provides the base DataSource implementation, which can be extended to
* create DataSources for specific data protocols, such as the IO Utility, the
* Get Utility, or custom functions.
*
* @module datasource
* @submodule datasource-local
*/
/**
* Base class for the DataSource Utility.
* @class DataSource.Local
* @extends Base
* @constructor
*/
var LANG = Y.Lang,
DSLocal = function() {
DSLocal.superclass.constructor.apply(this, arguments);
};
/////////////////////////////////////////////////////////////////////////////
//
// DataSource static properties
//
/////////////////////////////////////////////////////////////////////////////
Y.mix(DSLocal, {
/**
* Class name.
*
* @property NAME
* @type String
* @static
* @final
* @value "dataSourceLocal"
*/
NAME: "dataSourceLocal",
/////////////////////////////////////////////////////////////////////////////
//
// DataSource Attributes
//
/////////////////////////////////////////////////////////////////////////////
ATTRS: {
/**
* @attribute source
* @description Pointer to live data.
* @type MIXED
* @default null
*/
source: {
value: null
}
},
/**
* Global transaction counter.
*
* @property DataSource._tId
* @type Number
* @static
* @private
* @default 0
*/
_tId: 0,
/**
* Global in-progress transaction objects.
*
* @property DataSource.transactions
* @type Object
* @static
*/
transactions: {},
/**
* Returns data to callback.
*
* @method DataSource.issueCallback
* @param e {EventFacade} Event Facade.
* @param caller {DataSource} Calling DataSource instance.
* @static
*/
issueCallback: function (e, caller) {
var error = (e.error || e.response.error);
if(error) {
e.error = e.error || e.response.error;
caller.fire("error", e);
}
if(e.callback) {
var callbackFunc = (error && e.callback.failure) || e.callback.success;
if (callbackFunc) {
callbackFunc(e);
}
}
}
});
Y.extend(DSLocal, Y.Base, {
/**
* Internal init() handler.
*
* @method initializer
* @param config {Object} Config object.
* @private
*/
initializer: function(config) {
this._initEvents();
},
/**
* This method creates all the events for this module.
* @method _initEvents
* @private
*/
_initEvents: function() {
/**
* Fired when a data request is received.
*
* @event request
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object.
* - cfg (Object)
- Configuration object.
*
* @preventable _defRequestFn
*/
this.publish("request", {defaultFn: Y.bind("_defRequestFn", this), queuable:true});
/**
* Fired when raw data is received.
*
* @event data
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
* - data (Object)
- Raw data.
*
* @preventable _defDataFn
*/
this.publish("data", {defaultFn: Y.bind("_defDataFn", this), queuable:true});
/**
* Fired when response is returned.
*
* @event response
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
* - data (Object)
- Raw data.
* - response (Object)
- Normalized response object with the following properties:
*
* - results (Object)
- Parsed results.
* - meta (Object)
- Parsed meta data.
* - error (Boolean)
- Error flag.
*
*
*
* @preventable _defResponseFn
*/
this.publish("response", {defaultFn: Y.bind("_defResponseFn", this), queuable:true});
/**
* Fired when an error is encountered.
*
* @event error
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
* - data (Object)
- Raw data.
* - response (Object)
- Normalized response object with the following properties:
*
* - results (Object)
- Parsed results.
* - meta (Object)
- Parsed meta data.
* - error (Object)
- Error object.
*
*
*
*/
},
/**
* Manages request/response transaction. Must fire response
* event when response is received. This method should be implemented by
* subclasses to achieve more complex behavior such as accessing remote data.
*
* @method _defRequestFn
* @param e {Event.Facade} Event Facadewith the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
*
* @protected
*/
_defRequestFn: function(e) {
var data = this.get("source");
// Problematic data
if(LANG.isUndefined(data)) {
e.error = new Error("Local source undefined");
}
this.fire("data", Y.mix({data:data}, e));
},
/**
* Normalizes raw data into a response that includes results and meta properties.
*
* @method _defDataFn
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
* - data (Object)
- Raw data.
*
* @protected
*/
_defDataFn: function(e) {
var data = e.data,
meta = e.meta,
response = {
results: (LANG.isArray(data)) ? data : [data],
meta: (meta) ? meta : {}
};
this.fire("response", Y.mix({response: response}, e));
},
/**
* Sends data as a normalized response to callback.
*
* @method _defResponseFn
* @param e {Event.Facade} Event Facade with the following properties:
*
* - tId (Number)
- Unique transaction ID.
* - request (Object)
- The request.
* - callback (Object)
- The callback object with the following properties:
*
* - success (Function)
- Success handler.
* - failure (Function)
- Failure handler.
*
*
* - cfg (Object)
- Configuration object.
* - data (Object)
- Raw data.
* - response (Object)
- Normalized response object with the following properties:
*
* - results (Object)
- Parsed results.
* - meta (Object)
- Parsed meta data.
* - error (Boolean)
- Error flag.
*
*
*
* @protected
*/
_defResponseFn: function(e) {
// Send the response back to the callback
DSLocal.issueCallback(e, this);
},
/**
* Generates a unique transaction ID and fires request event.
*
* @method sendRequest
* @param request {Object} An object literal with the following properties:
*
* request- The request to send to the live data source, if any.
* callback- An object literal with the following properties:
*
* success- The function to call when the data is ready.
* failure- The function to call upon a response failure condition.
* argument- Arbitrary data payload that will be passed back to the success and failure handlers.
*
*
* cfg- Configuration object, if any.
*
* @return {Number} Transaction ID.
*/
sendRequest: function(request) {
request = request || {};
var tId = DSLocal._tId++;
this.fire("request", {tId:tId, request:request.request, callback:request.callback, cfg:request.cfg || {}});
return tId;
}
});
Y.namespace("DataSource").Local = DSLocal;
}, '3.3.0' ,{requires:['base']});