Rest.js #1

/*
	Copyright (c) 2004-2011, The Dojo Foundation All Rights Reserved.
	Available via Academic Free License >= 2.1 OR the modified BSD license.
	see: http://dojotoolkit.org/license for details
*/


if(!dojo._hasResource["dojox.rpc.Rest"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.rpc.Rest"] = true;
dojo.provide("dojox.rpc.Rest");

// Note: This doesn't require dojox.rpc.Service, and if you want it you must require it
// yourself, and you must load it prior to dojox.rpc.Rest.

// summary:
// 		This provides a HTTP REST service with full range REST verbs include PUT,POST, and DELETE.
// description:
// 		A normal GET query is done by using the service directly:
// 		| var restService = dojox.rpc.Rest("Project");
// 		| restService("4");
//		This will do a GET for the URL "/Project/4".
//		| restService.put("4","new content");
//		This will do a PUT to the URL "/Project/4" with the content of "new content".
//		You can also use the SMD service to generate a REST service:
// 		| var services = dojox.rpc.Service({services: {myRestService: {transport: "REST",...
// 		| services.myRestService("parameters");
//
// 		The modifying methods can be called as sub-methods of the rest service method like:
//  	| services.myRestService.put("parameters","data to put in resource");
//  	| services.myRestService.post("parameters","data to post to the resource");
//  	| services.myRestService['delete']("parameters");
	if(dojox.rpc && dojox.rpc.transportRegistry){
		// register it as an RPC service if the registry is available
		dojox.rpc.transportRegistry.register(
			"REST",
			function(str){return str == "REST";},
			{
				getExecutor : function(func,method,svc){
					return new dojox.rpc.Rest(
						method.name,
						(method.contentType||svc._smd.contentType||"").match(/json|javascript/), // isJson
						null,
						function(id, args){
							var request = svc._getRequest(method,[id]);
							request.url= request.target + (request.data ? '?'+  request.data : '');
							if(args && (args.start >= 0 || args.count >= 0)){
								request.headers = request.headers || {};
								request.headers.Range = "items=" + (args.start || '0') + '-' +
									(("count" in args && args.count != Infinity) ?
										(args.count + (args.start || 0) - 1) : '');
							}
							return request;
						}
					);
				}
			}
		);
	}
	var drr;

	function index(deferred, service, range, id){
		deferred.addCallback(function(result){
			if(deferred.ioArgs.xhr && range){
					// try to record the total number of items from the range header
					range = deferred.ioArgs.xhr.getResponseHeader("Content-Range");
					deferred.fullLength = range && (range=range.match(/\/(.*)/)) && parseInt(range[1]);
			}
			return result;
		});
		return deferred;
	}
	drr = dojox.rpc.Rest = function(/*String*/path, /*Boolean?*/isJson, /*Object?*/schema, /*Function?*/getRequest){
		// summary:
		//		Creates a REST service using the provided path.
		var service;
		// it should be in the form /Table/
		service = function(id, args){
			return drr._get(service, id, args);
		};
		service.isJson = isJson;
		service._schema = schema;
		// cache:
		//		This is an object that provides indexing service
		// 		This can be overriden to take advantage of more complex referencing/indexing
		// 		schemes
		service.cache = {
			serialize: isJson ? ((dojox.json && dojox.json.ref) || dojo).toJson : function(result){
				return result;
			}
		};
		// the default XHR args creator:
		service._getRequest = getRequest || function(id, args){
			if(dojo.isObject(id)){
				id = dojo.objectToQuery(id);
				id = id ? "?" + id: "";
			}
			if(args && args.sort && !args.queryStr){
				id += (id ? "&" : "?") + "sort("
				for(var i = 0; i<args.sort.length; i++){
					var sort = args.sort[i];
					id += (i > 0 ? "," : "") + (sort.descending ? '-' : '+') + encodeURIComponent(sort.attribute);
				}
				id += ")";
			}
			var request = {
				url: path + (id == null ? "" : id),
				handleAs: isJson ? 'json' : 'text',
				contentType: isJson ? 'application/json' : 'text/plain',
				sync: dojox.rpc._sync,
				headers: {
					Accept: isJson ? 'application/json,application/javascript' : '*/*'
				}
			};
			if(args && (args.start >= 0 || args.count >= 0)){
				request.headers.Range = "items=" + (args.start || '0') + '-' +
					(("count" in args && args.count != Infinity) ?
						(args.count + (args.start || 0) - 1) : '');
			}
			dojox.rpc._sync = false;
			return request;
		};
		// each calls the event handler
		function makeRest(name){
			service[name] = function(id,content){
				return drr._change(name,service,id,content); // the last parameter is to let the OfflineRest know where to store the item
			};
		}
		makeRest('put');
		makeRest('post');
		makeRest('delete');
		// record the REST services for later lookup
		service.servicePath = path;
		return service;
	};

	drr._index={};// the map of all indexed objects that have gone through REST processing
	drr._timeStamps={};
	// these do the actual requests
	drr._change = function(method,service,id,content){
		// this is called to actually do the put, post, and delete
		var request = service._getRequest(id);
		request[method+"Data"] = content;
		return index(dojo.xhr(method.toUpperCase(),request,true),service);
	};

	drr._get= function(service,id, args){
		args = args || {};
		// this is called to actually do the get
		return index(dojo.xhrGet(service._getRequest(id, args)), service, (args.start >= 0 || args.count >= 0), id);
	};

}