DIR : /home/kozerus/public_html/pn/uize/site-source/js/Uize/Comm/Ajax.js

/home/kozerus/public_html/pn/uize/site-source/js/Uize/Comm

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Comm.Ajax Class
|   /    / /    |
|  /    / /  /| |    ONLINE : http://www.uize.com
| /____/ /__/_| | COPYRIGHT : (c)2004-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://www.uize.com/license.html
*/

/* Module Meta Data
	type: Class
	importance: 9
	codeCompleteness: 95
	docCompleteness: 80
*/

/*?
	Introduction
		The =Uize.Comm.Ajax= class implements support for [[http://en.wikipedia.org/wiki/Ajax_(programming)][Ajax]] (Asynchronous JavaScript And XML) communication through the XMLHttpRequest (XHR) object.

		*DEVELOPERS:* `Jan Borgersen`, `Chris van Rensburg`, `Ben Ilegbodu`, `Tim Carter`, `Arthur Lee`, original code contributed by `Zazzle Inc.`

		In order to implement support for communication through the XMLHttpRequest object, this class overrides the implementation of the =performRequest= instance method inherited from the =Uize.Comm= base class. There are no additional methods or properties provided by this class - all the interface is provided in the =Uize.Comm= superclass.
*/

Uize.module ({
	name:'Uize.Comm.Ajax',
	required:'Uize.Url',
	builder:function (_superclass) {
		'use strict';

		/*** Class Constructor ***/
			var
				_nop = Uize.nop
			;

		return _superclass.subclass ({
			instanceMethods:{
				performRequest:function (_request,_callback) {
					var
						m = this,
						_returnType = _request.returnType,
						_returnTypeIsObject = _returnType == 'object',
						_origUrl = Uize.Url.fromParams (_request.url),
						_requestUrl = Uize.Url.resolve (
							_request.url,
							Uize.copyInto (
								{
									rnd:_request.cache == 'never' ? Uize.Url.getCacheDefeatStr () : null
								},
								_origUrl.comm_mode ? null : {comm_mode:'ajax'},
								_origUrl.output ? null : {output:'js'}
							)
						),
						_requestData = _request.data || '',
						_requestMethod = _request.requestMethod,
						_requestMethodIsPost = _requestMethod == 'POST',
						_xmlHttpRequest = m._xmlHttpRequest || (
							m._xmlHttpRequest = window.XMLHttpRequest
								? new XMLHttpRequest
								: new ActiveXObject ('Microsoft.XMLHTTP')
						)
					;
					_xmlHttpRequest.onreadystatechange = function () {
						if (_xmlHttpRequest.readyState == 4) {
							_xmlHttpRequest.onreadystatechange = _nop;

							if (_xmlHttpRequest.status == 200) {
								var _responseText = _xmlHttpRequest.responseText;
								if (_returnTypeIsObject || _returnType == 'xml')
									_request.responseXml = _xmlHttpRequest.responseXML
								;
								if (_returnTypeIsObject || _returnType == 'text')
									_request.responseText = _responseText
								;
								if (_returnTypeIsObject || _returnType == 'json')
									_request.responseJson = _responseText
										? Function ('var a=[' + _responseText + '];return a.pop()') ()
										: null
								;
								_xmlHttpRequest.abort();
								// no args means no error
								_callback ();
							}
							else {
								_xmlHttpRequest.abort();

								// callback with error object
								_callback ({
									status: _xmlHttpRequest.status,
									statusText: _xmlHttpRequest.statusText
								});
							}
						}
					};

					if (_xmlHttpRequest.upload) { // test if XHR2 upload support
						_xmlHttpRequest.upload.onprogress = function (_event) {
							m.fire({name: 'Progress', xhrEvent: _event});
						}
					}

					if (_requestMethodIsPost && !_requestData) {
						var _queryPos = _requestUrl.indexOf ('?');
						_requestData = _requestUrl.substr (_queryPos + 1);
						_requestUrl = _requestUrl.slice (0,_queryPos);
					}
					_xmlHttpRequest.open (_requestMethod,_requestUrl,true);
					if (_requestMethodIsPost) {
						// don't set the content-type request header if it's multipart/form-data; the built-in FormData object will take care of that
						_request.contentType != 'multipart/form-data' &&
							_xmlHttpRequest.setRequestHeader (
								'Content-type',
								_request.contentType || 'application/x-www-form-urlencoded'
							)
						;
						//_xmlHttpRequest.setRequestHeader ('Content-length', _requestData.length);
					}
					_xmlHttpRequest.send (_requestData);
				}
			}
		});
	}
});