source: Dev/trunk/src/client/dojo/request/util.js

define([
        'exports',
        '../errors/RequestError',
        '../errors/CancelError',
        '../Deferred',
        '../io-query',
        '../_base/array',
        '../_base/lang',
        '../promise/Promise'
], function(exports, RequestError, CancelError, Deferred, ioQuery, array, lang, Promise){
        exports.deepCopy = function deepCopy(target, source){
                for(var name in source){
                        var tval = target[name],
                                sval = source[name];
                        if(tval !== sval){
                                if(tval && typeof tval === 'object' && sval && typeof sval === 'object'){
                                        exports.deepCopy(tval, sval);
                                }else{
                                        target[name] = sval;
                                }
                        }
                }
                return target;
        };

        exports.deepCreate = function deepCreate(source, properties){
                properties = properties || {};
                var target = lang.delegate(source),
                        name, value;

                for(name in source){
                        value = source[name];

                        if(value && typeof value === 'object'){
                                target[name] = exports.deepCreate(value, properties[name]);
                        }
                }
                return exports.deepCopy(target, properties);
        };

        var freeze = Object.freeze || function(obj){ return obj; };
        function okHandler(response){
                return freeze(response);
        }
        function dataHandler (response) {
                return response.data || response.text;
        }

        exports.deferred = function deferred(response, cancel, isValid, isReady, handleResponse, last){
                var def = new Deferred(function(reason){
                        cancel && cancel(def, response);

                        if(!reason || !(reason instanceof RequestError) && !(reason instanceof CancelError)){
                                return new CancelError('Request canceled', response);
                        }
                        return reason;
                });

                def.response = response;
                def.isValid = isValid;
                def.isReady = isReady;
                def.handleResponse = handleResponse;

                function errHandler(error){
                        error.response = response;
                        throw error;
                }
                var responsePromise = def.then(okHandler).otherwise(errHandler);

                if(exports.notify){
                        responsePromise.then(
                                lang.hitch(exports.notify, 'emit', 'load'),
                                lang.hitch(exports.notify, 'emit', 'error')
                        );
                }

                var dataPromise = responsePromise.then(dataHandler);

                // http://bugs.dojotoolkit.org/ticket/16794
                // The following works around a leak in IE9 through the
                // prototype using lang.delegate on dataPromise and
                // assigning the result a property with a reference to
                // responsePromise.
                var promise = new Promise();
                for (var prop in dataPromise) {
                        if (dataPromise.hasOwnProperty(prop)) {
                                promise[prop] = dataPromise[prop];
                        }
                }
                promise.response = responsePromise;
                freeze(promise);
                // End leak fix


                if(last){
                        def.then(function(response){
                                last.call(def, response);
                        }, function(error){
                                last.call(def, response, error);
                        });
                }

                def.promise = promise;
                def.then = promise.then;

                return def;
        };

        exports.addCommonMethods = function addCommonMethods(provider, methods){
                array.forEach(methods||['GET', 'POST', 'PUT', 'DELETE'], function(method){
                        provider[(method === 'DELETE' ? 'DEL' : method).toLowerCase()] = function(url, options){
                                options = lang.delegate(options||{});
                                options.method = method;
                                return provider(url, options);
                        };
                });
        };

        exports.parseArgs = function parseArgs(url, options, skipData){
                var data = options.data,
                        query = options.query;
                
                if(data && !skipData){
                        if(typeof data === 'object'){
                                options.data = ioQuery.objectToQuery(data);
                        }
                }

                if(query){
                        if(typeof query === 'object'){
                                query = ioQuery.objectToQuery(query);
                        }
                        if(options.preventCache){
                                query += (query ? '&' : '') + 'request.preventCache=' + (+(new Date));
                        }
                }else if(options.preventCache){
                        query = 'request.preventCache=' + (+(new Date));
                }

                if(url && query){
                        url += (~url.indexOf('?') ? '&' : '?') + query;
                }

                return {
                        url: url,
                        options: options,
                        getHeader: function(headerName){ return null; }
                };
        };

        exports.checkStatus = function(stat){
                stat = stat || 0;
                return (stat >= 200 && stat < 300) || // allow any 2XX response code
                        stat === 304 ||                 // or, get it out of the cache
                        stat === 1223 ||                // or, Internet Explorer mangled the status code
                        !stat;                         // or, we're Titanium/browser chrome/chrome extension requesting a local file
        };
});