datasource-polling.js revision 4fc6a4b8ccaeb7aa902e0d78b6183a476a68f5b1
/**
* Extends DataSource with polling functionality.
*
* @module datasource
* @submodule datasource-polling
*/
/**
* Adds polling to the DataSource Utility.
* @class Pollable
* @extends DataSource.Local
*/
function Pollable() {
this._intervals = {};
}
Pollable.prototype = {
/**
* @property _intervals
* @description Hash of polling interval IDs that have been enabled,
* stored here to be able to clear all intervals.
* @private
*/
_intervals: null,
/**
* Sets up a polling mechanism to send requests at set intervals and
* forward responses to given callback.
*
* @method setInterval
* @param msec {Number} Length of interval in milliseconds.
* @param request {Object} An object literal with the following properties:
* <dl>
* <dt><code>request</code></dt>
* <dd>The request to send to the live data source, if any.</dd>
* <dt><code>callback</code></dt>
* <dd>An object literal with the following properties:
* <dl>
* <dt><code>success</code></dt>
* <dd>The function to call when the data is ready.</dd>
* <dt><code>failure</code></dt>
* <dd>The function to call upon a response failure condition.</dd>
* <dt><code>argument</code></dt>
* <dd>Arbitrary data payload that will be passed back to the success and failure handlers.</dd>
* </dl>
* </dd>
* <dt><code>cfg</code></dt>
* <dd>Configuration object, if any.</dd>
* </dl>
* @return {Number} Interval ID.
*/
setInterval: function(msec, request) {
var x = Y.later(msec, this, this.sendRequest, [ request ], true);
this._intervals[x.id] = x;
// First call happens immediately, but async
Y.later(0, this, this.sendRequest, [request]);
return x.id;
},
/**
* Disables polling mechanism associated with the given interval ID.
*
* @method clearInterval
* @param id {Number} Interval ID.
*/
clearInterval: function(id, key) {
// In case of being called by clearAllIntervals()
id = key || id;
if(this._intervals[id]) {
// Clear the interval
this._intervals[id].cancel();
// Clear from tracker
delete this._intervals[id];
}
},
/**
* Clears all intervals.
*
* @method clearAllIntervals
*/
clearAllIntervals: function() {
Y.each(this._intervals, this.clearInterval, this);
}
};
Y.augment(Y.DataSource.Local, Pollable);