jparreira/index.html

## index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
	<script type="text/javascript" src="http://storage-cdn.realtime.co/storage/1.0.0/realtime-storage-min.js"></script>
</head>
<body>
	<a href="javascript:void;" title="previous messages" id="aPreviousMessages">previous messages</a>
	<script type="text/javascript" src="list.js"></script>
</body>
</html>

## list.js
// This example assumes you have a table named chatMessages with the following key-schema:
// primary key -> chatid (string)
// secondary key -> timestamp (number)
//
// It should also contain an attribute named text (string)

var credentials = {
	applicationKey: "2Ze1dz", // change this to your application key
	authenticationToken: "userToken" // change this to your authenticated token if security is being used
};

var storage = Realtime.Storage.create(credentials);

// we'll use Operation to get the other previous messages
// The Operation object gives you access to the underlying REST services
var operation = new Realtime.Storage.Operation(credentials);

// value of the tables primary key
var chatRoom = "test-list";
// all messages will be stored here
var messages = [];
// number of messages to get (limit)
var count = 3;

// get the last "count" messages in chatRoom
table = storage.table("chatMessages");

table.limit(count).desc().equals({ item: "chatid", value: chatRoom }).getItems(function(itemSnapshot) {

	if(itemSnapshot) {
		// unshift will insert the messages in the reverse order
		messages.unshift(itemSnapshot.val());
	}
	else {
		// Writes each message at the console in the right order
		for(var i = 0; i < messages.length; ++i) {
			console.log(messages[i].text);
		}

		var link = document.getElementById("aPreviousMessages");

		// user wants the previous messages
		link.onclick = function() {
			// get the other previous messages starting from the oldest message shown
			// we'll use the startKey parameter to tell Cloud Storage the starting point
			operation.queryItems({
				table: "chatMessages",
				key: { primary: chatRoom },
				// the key from where the search should resume
				startKey: messages.length != 0 ? {
					primary: messages[0].chatid,
					secondary: messages[0].timestamp
				} : undefined,
				limit: count,
				searchForward: false
			}, function(data) {
				var lastMessages = [];
				// unshift will insert the messages in the reverse order
				for(var i = 0; i < data.items.length; ++i) {
					lastMessages.unshift(data.items[i]);
				}

				// display messages in the correct order
				for(var i = 0; i < lastMessages.length; ++i) {
					console.log(lastMessages[i].text);
				}

				// add messages to the global array containing all displayed messages so far
				messages = lastMessages.concat(messages);

				// if there's no stopKey this means there are no more messages to retrieve
				if(!data.stopKey) {
					link.innerHTML = "No more messages";
				}

			}, function(err) {
				console.log(err);
			});

			return false;
		};
	}
});
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="ISO-8859-1">
	<title>Insert title here</title>
	<script type="text/javascript" src="http://storage-cdn.realtime.co/storage/1.0.0/realtime-storage-min.js"></script>
	</head>
	<body>
	<a href="javascript:void;" title="previous messages" id="aPreviousMessages">previous messages</a>
	<script type="text/javascript" src="list.js"></script>
	</body>
	</html>
	// This example assumes you have a table named chatMessages with the following key-schema:
	// primary key -> chatid (string)
	// secondary key -> timestamp (number)
	//
	// It should also contain an attribute named text (string)

	var credentials = {
	applicationKey: "2Ze1dz", // change this to your application key
	authenticationToken: "userToken" // change this to your authenticated token if security is being used
	};

	var storage = Realtime.Storage.create(credentials);

	// we'll use Operation to get the other previous messages
	// The Operation object gives you access to the underlying REST services
	var operation = new Realtime.Storage.Operation(credentials);

	// value of the tables primary key
	var chatRoom = "test-list";
	// all messages will be stored here
	var messages = [];
	// number of messages to get (limit)
	var count = 3;

	// get the last "count" messages in chatRoom
	table = storage.table("chatMessages");

	table.limit(count).desc().equals({ item: "chatid", value: chatRoom }).getItems(function(itemSnapshot) {

	if(itemSnapshot) {
	// unshift will insert the messages in the reverse order
	messages.unshift(itemSnapshot.val());
	}
	else {
	// Writes each message at the console in the right order
	for(var i = 0; i < messages.length; ++i) {
	console.log(messages[i].text);
	}

	var link = document.getElementById("aPreviousMessages");

	// user wants the previous messages
	link.onclick = function() {
	// get the other previous messages starting from the oldest message shown
	// we'll use the startKey parameter to tell Cloud Storage the starting point
	operation.queryItems({
	table: "chatMessages",
	key: { primary: chatRoom },
	// the key from where the search should resume
	startKey: messages.length != 0 ? {
	primary: messages[0].chatid,
	secondary: messages[0].timestamp
	} : undefined,
	limit: count,
	searchForward: false
	}, function(data) {
	var lastMessages = [];
	// unshift will insert the messages in the reverse order
	for(var i = 0; i < data.items.length; ++i) {
	lastMessages.unshift(data.items[i]);
	}

	// display messages in the correct order
	for(var i = 0; i < lastMessages.length; ++i) {
	console.log(lastMessages[i].text);
	}

	// add messages to the global array containing all displayed messages so far
	messages = lastMessages.concat(messages);

	// if there's no stopKey this means there are no more messages to retrieve
	if(!data.stopKey) {
	link.innerHTML = "No more messages";
	}

	}, function(err) {
	console.log(err);
	});

	return false;
	};
	}
	});