emk/comet_client.coffee

## comet_client.coffee
# Client-side Comet code.  See comet_server.coffee for instructions.
client = new Faye.Client '/faye', timeout: 90

# Attach a security key to all our subscription messages.
client.addExtension
  outgoing: (msg, callback) ->
    return callback(msg) unless msg.channel is '/meta/subscribe'
    (msg.ext ?= {}).authToken = 'secret'
    callback(msg)

# Listen for messages on the specified channel.
client.subscribe '/msg', (message) ->
  document.chat.output.value += "#{message}\n"

# This function is called when the user enters a message.
window.sendMessage = ->
  client.publish '/msg', document.chat.input.value
  document.chat.input.value = ''

## comet_client.html
<!-- Client-side HTML.  See comet_server.coffee for instructions. -->
<html>
  <head>
    <title>Faye Comet demo with Node.js and Coffee</title>
    <script type="text/javascript" src="/faye.js"></script>
    <script type="text/javascript" src="/comet_client.js"></script>
  </head>
  <body>
    <h1>Faye Comet demo with Node.js and Coffee</h1>

    <p>Open multiple copies of this page and enter text below.</p>

    <form name='chat' action='javascript:sendMessage()'>
      <label for='input'>Input:</label>
      <input name='input' type='text' size='40'><br/>
      <textarea name='output' rows='20' cols='40'></textarea>
    </form>
  </body>
</html>

## comet_server.coffee
# Browser-based chat using Node.js, Comet, Faye and CoffeeScript
# by Eric Kidd
#
# To run this code, install Node.js and npm (the Node package manager),
# and run:
#
#   npm install coffee-script
#   npm install express
#   npm install faye
#   coffee comet_server.coffee
#
# Then visit http://127.0.0.1:8000/ in your web browser.  This has been
# tested with Chrome & Mobile Chrome.

sys = require 'sys'
fs = require 'fs'
coffee = require 'coffee-script'
express = require 'express'
faye = require 'faye'

# Compile our client-side code to JavaScript.  We do this every time we
# serve it to make tweaking the code easier.
comet_client_js = ->
  coffee.compile(fs.readFileSync('./comet_client.coffee', 'utf-8'))

# Serve static HTML page and client-side JavaScript.
app = express.createServer()
app.get '/', (req, res) ->
  res.contentType 'text/html'
  res.sendfile './comet_client.html'
app.get '/comet_client.js', (req, res) ->
  res.contentType 'text/javascript'
  res.send(comet_client_js())

# Hook up Faye's Comet messaging service.
adapter = new faye.NodeAdapter mount: '/faye', timeout: 45
adapter.attach(app)

# Check the authentication token on every subscription request.
adapter.addExtension
  incoming: (msg, callback) ->
    return callback(msg) unless msg.channel is '/meta/subscribe'
    unless msg.subscription is '/msg' and msg.ext?.authToken is 'secret'
      msg.error = "Invalid authToken"
    callback(msg)

app.listen 8000
sys.puts "Server running at http://127.0.0.1:8000/"
	# Client-side Comet code. See comet_server.coffee for instructions.
	client = new Faye.Client '/faye', timeout: 90

	# Attach a security key to all our subscription messages.
	client.addExtension
	outgoing: (msg, callback) ->
	return callback(msg) unless msg.channel is '/meta/subscribe'
	(msg.ext ?= {}).authToken = 'secret'
	callback(msg)

	# Listen for messages on the specified channel.
	client.subscribe '/msg', (message) ->
	document.chat.output.value += "#{message}\n"

	# This function is called when the user enters a message.
	window.sendMessage = ->
	client.publish '/msg', document.chat.input.value
	document.chat.input.value = ''
	<!-- Client-side HTML. See comet_server.coffee for instructions. -->
	<html>
	<head>
	<title>Faye Comet demo with Node.js and Coffee</title>
	<script type="text/javascript" src="/faye.js"></script>
	<script type="text/javascript" src="/comet_client.js"></script>
	</head>
	<body>
	<h1>Faye Comet demo with Node.js and Coffee</h1>

	<p>Open multiple copies of this page and enter text below.</p>

	<form name='chat' action='javascript:sendMessage()'>
	<label for='input'>Input:</label>
	<input name='input' type='text' size='40'><br/>
	<textarea name='output' rows='20' cols='40'></textarea>
	</form>
	</body>
	</html>
	# Browser-based chat using Node.js, Comet, Faye and CoffeeScript
	# by Eric Kidd
	#
	# To run this code, install Node.js and npm (the Node package manager),
	# and run:
	#
	# npm install coffee-script
	# npm install express
	# npm install faye
	# coffee comet_server.coffee
	#
	# Then visit http://127.0.0.1:8000/ in your web browser. This has been
	# tested with Chrome & Mobile Chrome.

	sys = require 'sys'
	fs = require 'fs'
	coffee = require 'coffee-script'
	express = require 'express'
	faye = require 'faye'

	# Compile our client-side code to JavaScript. We do this every time we
	# serve it to make tweaking the code easier.
	comet_client_js = ->
	coffee.compile(fs.readFileSync('./comet_client.coffee', 'utf-8'))

	# Serve static HTML page and client-side JavaScript.
	app = express.createServer()
	app.get '/', (req, res) ->
	res.contentType 'text/html'
	res.sendfile './comet_client.html'
	app.get '/comet_client.js', (req, res) ->
	res.contentType 'text/javascript'
	res.send(comet_client_js())

	# Hook up Faye's Comet messaging service.
	adapter = new faye.NodeAdapter mount: '/faye', timeout: 45
	adapter.attach(app)

	# Check the authentication token on every subscription request.
	adapter.addExtension
	incoming: (msg, callback) ->
	return callback(msg) unless msg.channel is '/meta/subscribe'
	unless msg.subscription is '/msg' and msg.ext?.authToken is 'secret'
	msg.error = "Invalid authToken"
	callback(msg)

	app.listen 8000
	sys.puts "Server running at http://127.0.0.1:8000/"