Add README.

README.md

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+# Node.js and Redis Pub-Sub
+
+[Node.js](http://nodejs.org/) is a perfect platform for creating event driven
+applications. [Redis](http://code.google.com/p/redis/) and [WebSockets](http://en.wikipedia.org/wiki/WebSockets)
+are great companions to Node.js. The following tutorial will walk through the
+steps to build a web application that streams real time flight information
+using Node.js, Redis, and WebSockets.
+
+## Dependencies
+
+Node.js, Redis, and a WebSocket enabled browser (Firefox 4, Google Chrome 4,
+or Safari 5) are required. A tutorial covering the installation of Node.js can
+be found [here]()
+
+The easiest way to get a Redis instance would be to use [Redis To Go](http://redistogo.com/).
+The free plan is all that is needed for this tutorial. If you wish to install
+locally run the following commands:
+
+    $ git clone http://github.com/antirez/redis.git
+	$ cd redis/src
+	$ make
+	$ sudo make install
+	$ cd ../..
+	$ rm -rf redis
+
+Now you can start a Redis instance locally using the `redis-server` command.
+
+## Create the Project
+
+Create a directory for the project. We will name the project "Flight Stream".
+
+    $ mkdir flight-stream
+	$ cd flight-stream
+
+The project will require the Node.js Redis client [`redis-client`](http://github.com/fictorial/redis-node-client),
+the WebSocket library [`node-websocket-server`](http://github.com/miksago/node-websocket-server),
+and the MIME library [node-mime](http://github.com/bentomas/node-mime). Create
+a `lib` directory and copy the libraries to this directory.
+
+	$ mkdir lib
+	$ cd lib
+	$ curl -O http://github.com/fictorial/redis-node-client/raw/master/lib/redis-client.js \
+	       -O http://github.com/bentomas/node-mime/raw/master/mime.js \
+	       -O http://github.com/miksago/node-websocket-server/raw/master/lib/ws.js
+	$ mkdir ws
+	$ cd ws
+	$ curl -O http://github.com/miksago/node-websocket-server/raw/master/lib/ws/connection.js \
+		   -O http://github.com/miksago/node-websocket-server/raw/master/lib/ws/manager.js
+	$ cd ../..
+
+## Create the Server
+
+Initially the Node.js server will simply server the static index.html file that
+will be create. Create the `server.js` file and add the following code:
+
+	require.paths.unshift(__dirname + '/lib');
+
+	var fs = require('fs'),
+		ws = require('ws'),
+		sys = require('sys'),
+		url = require('url'),
+		http = require('http'),
+		path = require('path'),
+		mime = require('mime'),
+		redis = require('redis-client');
+
+	var httpServer = http.createServer( function(request, response) {
+		var pathname = url.parse(request.url).pathname;
+		if (pathname == "/") pathname = "index.html";
+		var filename = path.join(process.cwd(), 'public', pathname);
+
+		path.exists(filename, function(exists) {
+			if (!exists) {
+				response.writeHead(404, {"Content-Type": "text/plain"});
+				response.write("404 Not Found");
+				response.end();
+				return;
+			}
+
+			response.writeHead(200, {'Content-Type': mime.lookup(filename)});
+			fs.createReadStream(filename, {
+				'flags': 'r',
+				'encoding': 'binary',
+				'mode': 0666,
+				'bufferSize': 4 * 1024
+			}).addListener("data", function(chunk) {
+				response.write(chunk, 'binary');
+			}).addListener("close",function() {
+				response.end();
+			});
+		});
+	});
+
+
+	var server = ws.createServer({}, httpServer);
+
+	server.listen(8000);
+
+The `httpServer` serves the static files in the `public` directory. The
+`server` is what will be handling the WebSocket connections.
+
+Create the `public` directory:
+
+	$ mkdir public
+
+Now copy the source for the index and stylesheets from [github](http://github.com/waratuman/flight-stream).
+
+	$ cd public
+	$ curl -O http://github.com/waratuman/flight-stream/raw/master/public/application.css \
+           -O http://github.com/waratuman/flight-stream/raw/master/public/reset.css \
+		   -O http://github.com/waratuman/flight-stream/raw/master/public/text.css \
+		   -O http://github.com/waratuman/flight-stream/raw/master/public/index.html
+	$ cd images
+	$ curl -O 
+
+At this point you should be able to run `node server.js` and see the index
+page when you got to `localhost:8000`.
+
+Now lets get `redis-client` working in the server. The following lines
+establish a connection to Redis. The `connected` and `reconnected` listeners
+authenticate the connection after it has been established.
+
+	var db = redis.createClient(9281, 'goosefish.redistogo.com');
+	var dbAuth = function() { db.auth('dc64f7b818f4e3ec2e3d3d033e3e5ff4'); }
+	db.addListener('connected', dbAuth);
+	db.addListener('reconnected', dbAuth);
+	dbAuth();
+
+Now subscribe to the `flight_stream` channel on Redis.
+
+	db.subscribeTo("flight_stream", function(channel, message, pattern) {
+		try { var flight = JSON.parse(message); }
+		catch (SyntaxError) { return false; }
+
+		if ( flight.origin.iata == "BOS" || flight.destination.iata == "BOS") {
+			server.broadcast(message);
+		}
+	});
+
+Whenever a message is published the function passed to the `subscribeTo`
+method will get called. In this case we try to parse the message as JSON then
+publish it to all of the clients if the flight is leaving Boston or arriving
+at Boston.
+
+# Client
+
+Next the client will need to be coded. I previously created the HTML for this
+app, so all that we need to do is set up the WebSockets.
+
+Open `public/application.js` and insert the following code. This code will
+create a WebSocket if the browser supports it and if it does, create a
+connection with the server. When a message is received, another row will be
+inserted on the page displaying the flight.
+
+	function delay_color(mins) {
+		var min = parseInt(mins);
+		if (min <= -15) return 'green';
+		else if (min <= 0) return 'green';
+		else if (min <= 15) return 'orange';
+		else return 'red';
+	}
+
+	function delay_name(mins) {
+		var min = parseInt(mins);
+		if (min <= 0) return 'On-Time';
+		else return 'Delayed';
+	}
+
+	var ws;
+	var connect = function() {
+		if (!window['WebSocket']) {
+			alert("No WebSocket support.");
+			return;
+		}
+
+		ws = new WebSocket('ws://' + window.location.host);
+		ws.onmessage = function(evt) {
+			try { var flight = JSON.parse(evt.data); }
+			catch (SyntaxError) { return false; }
+
+			$('table.flight-updates > tbody').prepend(
+				'<tr>' +
+					'<td>' + flight.airline.icao + ' ' + flight.number + '</td>' +
+					'<td>' + flight.origin.iata + '</td>' +
+					'<td>' + flight.destination.iata + '</td>' +
+					'<td>' +
+						'<div class="tag ' + delay_color(flight.destination.gate_delay) + '">' +
+							delay_name(flight.destination.gate_delay) +
+							'<span>' + flight.destination.gate_delay + ' min</span>' +
+						'</div>'+
+					'</td>'+
+					'<td>' + flight.destination.gate + '</td>' +
+				'</tr>');
+		};
+	};
+
+	$(document).ready( function() {
+		connect();
+	});
+
+The functions `delay_color` and `delay_name` are helper functions for
+displaying text and selecting the right class for styling.
+
+Now you can start the server, go to [http://localhost:8000/](http://localhost:8000/)
+and you should start seeing updates roll in. If you are using your own Redis,
+you are going to need to publish something to the `flight_stream`. Here is a 
+sample message that you can use:
+
+	{"number":"482","status":"Scheduled","origin":{"gate_delay":0,"icao":"KSFO","name":"San Francisco International Airport","iata":"SFO","gate":"3-88"},"destination":{"gate_delay":0,"icao":"KBOS","name":"Denver International Airport","iata":"BOS","gate":"-"},"airline":{"icao":"UAL","name":"United Airlines","iata":"UA"}}
+
+If you are using the Redis instance used throughout the tutorial, you will
+start seeing flight come up. I will be publishing some data every few seconds
+to the instance.

server.js

@@ -44,7 +44,7 @@ var httpServer = http.createServer( function(request, response) {
 
 var server = ws.createServer({}, httpServer);
 
-db.subscribeTo("*", function(channel, message, pattern) {
+db.subscribeTo("flight_stream", function(channel, message, pattern) {
 	try { var flight = JSON.parse(message); }
 	catch (SyntaxError) { return false; }