callback_lec2.js

// 1. We are going to make an ajax request.
// 2. We are going to GET some response TEXT.
// 3. We are going to append the TEXT to the DOM.

// Callback to wait for DOM load event
$(function(){

	// //Start ajax
	// var getData = function(callBack){
	// 	return $.ajax({
	// 		url: "/responses/someId",
	// 		method: "GET",
	// 		async: false,
	// 		success: function(data){
	// 			callBack(data)
	// 		}
	// 	});
	// }

	// //console.log(getData());
	// var appendItem = function(data){
	// 	$("body").append(data["text"]);
	// }

	// getData(appendItem);


	/*
	*  Get some Data using an ajax request
	* @item  		something we're going to be processing/making
	* 	making a request for
	* @callBack some function to run afterward/later	
	*/
	var getData = function(item, callBack){
		// Send item back with PROCESSED prepended
		//callBack("PROCESSED " + item)
		
		$.ajax({
			url: "/responses/"+item,
			method: "GET",
			success: function(data){
				callBack(data["text"]); 
			}
		})

	}

	/*
	*  Takes a list of things and processes each item
	*		recursively
	*
	* @items 				a list of things to be processed
	* @doneCallback what to do when finished processing items.
	* @doneData			data that has been processed and added to the
	*									list
	*/

	var getMany = function(items, doneCallback, doneData){
		var doneData = doneData || [];

		// Terminating condition
		if(items.length == 0){
			doneCallback(doneData);
		} else {

			// items.shift() => returns first item in items list
			// 		items now has one less item in it.
			// So ["Larry", "Moe", "Curly"].shift() => "Larry"
			//		items => ["Moe", "Curly"]
			//		getData("Larry", anonFunc) 
			getData(items.shift(), function(data){
				doneData.push(data);
				console.log("Inner @data: ", data);
				console.log("Inner @doneData: ", doneData);
				getMany(items,doneCallback, doneData);
			})
		}
	}


	getMany(["Larry", "Moe", "Curly"], function(data){
			console.log("Outer @doneCallback: ", data);
			console.log(stuff = _.map(data, function(item){
				return item.replace("PROCESSED", "FINISHED");
			}))
			$("body").append(stuff.join())
	})













})