datasource-get.js revision 550a487c1a9f2ed0b47672fe6521a0a2067483b0
YUI.add('datasource-get', function(Y) {
/**
* Provides a DataSource implementation which can be used to retrieve data via the Get Utility.
*
* @module datasource
* @submodule datasource-get
*/
/**
* Get Utility subclass for the DataSource Utility.
* @class DataSource.Get
* @extends DataSource.Local
* @constructor
*/
var DSGet = function() {
DSGet.superclass.constructor.apply(this, arguments);
};
Y.DataSource.Get = Y.extend(DSGet, Y.DataSource.Local, {
/**
* Passes query string to Get Utility. Fires <code>response</code> event when
* response is received asynchronously.
*
* @method _defRequestFn
* @param e {Event.Facade} Event Facade with the following properties:
* <dl>
* <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>
* <dt>request (Object)</dt> <dd>The request.</dd>
* <dt>callback (Object)</dt> <dd>The callback object with the following properties:
* <dl>
* <dt>success (Function)</dt> <dd>Success handler.</dd>
* <dt>failure (Function)</dt> <dd>Failure handler.</dd>
* </dl>
* </dd>
* <dt>cfg (Object)</dt> <dd>Configuration object.</dd>
* </dl>
* @protected
*/
_defRequestFn: function(e) {
var uri = this.get("source"),
get = this.get("get"),
guid = Y.guid().replace(/\-/g, '_'),
generateRequest = this.get( "generateRequestCallback" ),
o;
/**
* Stores the most recent request id for validation against stale
* response handling.
*
* @property _last
* @type {String}
* @protected
*/
this._last = guid;
// Dynamically add handler function with a closure to the callback stack
// for access to guid
YUI.Env.DataSource.callbacks[guid] = Y.bind(function(response) {
delete YUI.Env.DataSource.callbacks[guid];
delete Y.DataSource.Local.transactions[e.tId];
var process = this.get('asyncMode') !== "ignoreStaleResponses" ||
this._last === guid;
if (process) {
this.fire("data", Y.mix({ data: response }, e));
} else {
}
}, this);
// Add the callback param to the request url
uri += e.request + generateRequest.call( this, guid );
Y.DataSource.Local.transactions[e.tId] = get.script(uri, {
autopurge: true,
// Works in Firefox only....
onFailure: Y.bind(function(e, o) {
delete YUI.Env.DataSource.callbacks[guid];
delete Y.DataSource.Local.transactions[e.tId];
e.error = new Error(o.msg || "Script node data failure");
this.fire("data", e);
}, this, e),
onTimeout: Y.bind(function(e, o) {
delete YUI.Env.DataSource.callbacks[guid];
delete Y.DataSource.Local.transactions[e.tId];
e.error = new Error(o.msg || "Script node data timeout");
this.fire("data", e);
}, this, e)
});
return e.tId;
},
/**
* Default method for adding callback param to url. See
* generateRequestCallback attribute.
*
* @method _generateRequest
* @param guid {String} unique identifier for callback function wrapper
* @protected
*/
_generateRequest: function (guid) {
return "&" + this.get("scriptCallbackParam") +
"=YUI.Env.DataSource.callbacks." + guid;
}
}, {
/**
* Class name.
*
* @property NAME
* @type String
* @static
* @final
* @value "dataSourceGet"
*/
NAME: "dataSourceGet",
////////////////////////////////////////////////////////////////////////////
//
// DataSource.Get Attributes
//
////////////////////////////////////////////////////////////////////////////
ATTRS: {
/**
* Pointer to Get Utility.
*
* @attribute get
* @type Y.Get
* @default Y.Get
*/
get: {
value: Y.Get,
cloneDefaultValue: false
},
/**
* Defines request/response management in the following manner:
* <dl>
* <!--<dt>queueRequests</dt>
* <dd>If a request is already in progress, wait until response is
* returned before sending the next request.</dd>
* <dt>cancelStaleRequests</dt>
* <dd>If a request is already in progress, cancel it before
* sending the next request.</dd>-->
* <dt>ignoreStaleResponses</dt>
* <dd>Send all requests, but handle only the response for the most
* recently sent request.</dd>
* <dt>allowAll</dt>
* <dd>Send all requests and handle all responses.</dd>
* </dl>
*
* @attribute asyncMode
* @type String
* @default "allowAll"
*/
asyncMode: {
value: "allowAll"
},
/**
* Callback string parameter name sent to the remote script. By default,
* requests are sent to
* &#60;URI&#62;?&#60;scriptCallbackParam&#62;=callbackFunction
*
* @attribute scriptCallbackParam
* @type String
* @default "callback"
*/
scriptCallbackParam : {
value: "callback"
},
/**
* Accepts the DataSource instance and a callback ID, and returns a callback
* param/value string that gets appended to the script URI. Implementers
* can customize this string to match their server's query syntax.
*
* @attribute generateRequestCallback
* @type Function
*/
generateRequestCallback : {
value: function () {
return this._generateRequest.apply(this, arguments);
}
}
}
});
YUI.namespace("Env.DataSource.callbacks");
}, '@VERSION@' ,{requires:['datasource-local', 'get']});