README.rdoc in faye-websocket-0.2.0 vs README.rdoc in faye-websocket-0.3.0

@@ -2,35 +2,46 @@
 
 This is a robust, general-purpose WebSocket implementation extracted from the
 {Faye}[http://faye.jcoglan.com] project. It provides classes for easily building
 WebSocket servers and clients in Ruby. It does not provide a server itself, but
 rather makes it easy to handle WebSocket connections within an existing
-{Rack}[http://rack.rubyforge.org/] application running under
-{Thin}[http://code.macournoyer.com/thin/]. It does not provide any abstraction
-other than the standard {WebSocket API}[http://dev.w3.org/html5/websockets/].
+{Rack}[http://rack.rubyforge.org/] application. It does not provide any
+abstraction other than the standard
+{WebSocket API}[http://dev.w3.org/html5/websockets/].
 
+It also provides an abstraction for handling {EventSource}[http://dev.w3.org/html5/eventsource/]
+connections, which are one-way connections that allow the server to push data to
+the client. They are based on streaming HTTP responses and can be easier to
+access via proxies than WebSockets.
+
+Currently, the following web servers are supported, and can be accessed directly
+or via HAProxy:
+
+* {Thin}[http://code.macournoyer.com/thin/]
+* {Rainbows}[http://rainbows.rubyforge.org/] using EventMachine
+* {Goliath}[http://postrank-labs.github.com/goliath/]
+
 The server-side socket can process {draft-75}[http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-75],
 {draft-76}[http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76],
 {hybi-07}[http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07]
 and later versions of the protocol. It selects protocol versions automatically,
 supports both +text+ and +binary+ messages, and transparently handles +ping+,
 +pong+, +close+ and fragmented messages.
 
 
-== Accepting WebSocket connections in Rack
+== Handling WebSocket connections in Rack
 
-You can handle WebSockets on the server side by listening for HTTP Upgrade
-requests, and creating a new socket for the request. This socket object exposes
-the usual WebSocket methods for receiving and sending messages. For example this
-is how you'd implement an echo server:
+You can handle WebSockets on the server side by listening for requests using the
+<tt>Faye::WebSocket.websocket?</tt> method, and creating a new socket for the
+request. This socket object exposes the usual WebSocket methods for receiving
+and sending messages. For example this is how you'd implement an echo server:
 
+    # app.rb
     require 'faye/websocket'
-    require 'rack'
-    require 'eventmachine'
     
-    app = lambda do |env|
-      if env['HTTP_UPGRADE']
+    App = lambda do |env|
+      if Faye::WebSocket.websocket?(env)
         ws = Faye::WebSocket.new(env)
         
         ws.onmessage = lambda do |event|
           ws.send(event.data)
         end
@@ -38,31 +49,37 @@
         ws.onclose = lambda do |event|
           p [:close, event.code, event.reason]
           ws = nil
         end
         
-        # Thin async response
-        [-1, {}, []]
+        # Return async Rack response
+        ws.rack_response
         
       else
         # Normal HTTP request
         [200, {'Content-Type' => 'text/plain'}, ['Hello']]
       end
     end
-    
-    EM.run {
-      thin = Rack::Handler.get('thin')
-      thin.run(app, :Port => 9292)
-    }
 
+This is a standard Rack app, so it can be run using a <tt>config.ru</tt> file.
+However, so that incoming requests can be properly prepared to process WebSocket
+connections, you need to tell <tt>Faye::WebSocket</tt> which adapter to load;
+this can be either +thin+, +rainbows+ or +goliath+. If one of these servers is
+already loaded before <tt>faye/websocket</tt> is loaded, it will load
+appropriate adapters automatically.
 
+    # config.ru
+    require './app'
+    Faye::WebSocket.load_adapter('thin')
+    run App
+
+
 == Using the WebSocket client
 
 The client supports both the plain-text +ws+ protocol and the encrypted +wss+
 protocol, and has exactly the same interface as a socket you would use in a web
-browser. On the wire it identifies itself as hybi-13, though it's compatible
-with servers speaking later versions of the protocol.
+browser. On the wire it identifies itself as hybi-13.
 
     require 'faye/websocket'
     require 'eventmachine'
     
     EM.run {
@@ -123,18 +140,186 @@
 * <b><tt>send(message)</tt></b> accepts either a +String+ or an +Array+ of
   byte-sized integers and sends a text or binary message over the connection to
   the other peer.
 * <b><tt>close(code, reason)</tt></b> closes the connection, sending the given
   status code and reason text, both of which are optional.
-* <b><tt>protocol</tt></b> is a string or +nil+ identifying the subprotocol th
-  socket is using.
+* <b><tt>protocol</tt></b> is a string (which may be empty) identifying the
+  subprotocol the socket is using.
 
 
+== Handling EventSource connections in Rack
+
+EventSource connections provide a very similar interface, although because they
+only allow the server to send data to the client, there is no +onmessage+ API.
+EventSource allows the server to push text messages to the client, where each
+message has an optional event-type and ID.
+
+    # app.rb
+    require 'faye/websocket'
+    
+    App = lambda do |env|
+      if Faye::EventSource.eventsource?(env)
+        es = Faye::EventSource.new(env)
+        p [:open, es.url, es.last_event_id]
+        
+        # Periodically send messages
+        loop = EM.add_periodic_timer(1) { es.send('Hello') }
+        
+        es.onclose = lambda do |event|
+          EM.cancel_timer(loop)
+          es = nil
+        end
+        
+        # Return async Rack response
+        es.rack_response
+        
+      else
+        # Normal HTTP request
+        [200, {'Content-Type' => 'text/plain'}, ['Hello']]
+      end
+    end
+
+The +send+ method takes two optional parameters, <tt>:event</tt> and
+<tt>:id</tt>. The default event-type is <tt>'message'</tt> with no ID. For
+example, to send a +notification+ event with ID +99+:
+
+    es.send('Breaking News!', :event => 'notification', :id => '99')
+
+The +EventSource+ object exposes the following properties:
+
+* <b><tt>url</tt></b> is a string containing the URL the client used to create
+  the EventSource.
+* <b><tt>last_event_id</tt></b> is a string containing the last event ID
+  received by the client. You can use this when the client reconnects after a
+  dropped connection to determine which messages need resending.
+
+When you initialize an EventSource with <tt>Faye::EventSource.new</tt>, you can
+pass configuration options after the +env+ parameter. Available options are:
+
+* <b><tt>:retry</tt></b> is a number that tells the client how long (in seconds)
+  it should wait after a dropped connection before attempting to reconnect.
+* <b><tt>:ping</tt></b> is a number that tells the server how often (in seconds)
+  to send 'ping' packets to the client to keep the connection open, to defeat
+  timeouts set by proxies. The client will ignore these messages.
+
+For example, this creates a connection that pings every 15 seconds and is
+retryable every 10 seconds if the connection is broken:
+
+    es = Faye::EventSource.new(es, :ping => 15, :retry => 10)
+
+
+== Running your socket application
+
+To use this library you must be using an EventMachine-based server; currently
+Thin, Rainbows and Goliath are supported.
+
+
+=== Running the app with Thin
+
+Thin can be started via the command line if you've set up a <tt>config.ru</tt>
+file for your application:
+
+    thin start -R config.ru -p 9292
+
+Or, you can use +rackup+. In development mode, this adds middlewares that don't
+work with async apps, so you must start it in production mode:
+
+    rackup config.ru -s thin -E production -p 9292
+
+It can also be started using the <tt>Rack::Handler</tt> interface common to many
+Ruby servers. It must be run using EventMachine, and you can configure Thin
+further in a block passed to +run+:
+
+    require 'eventmachine'
+    require 'rack'
+    require 'thin'
+    require './app'
+    
+    EM.run {
+      thin = Rack::Handler.get('thin')
+      
+      thin.run(App, :Port => 9292) do |server|
+        # You can set options on the server here, for example to set up SSL:
+        server.ssl_options = {
+          :private_key_file => 'path/to/ssl.key',
+          :cert_chain_file  => 'path/to/ssl.crt'
+        }
+        server.ssl = true
+      end
+    }
+
+
+=== Running the app with Rainbows
+
+<tt>Faye::WebSocket</tt> can only be run using EventMachine. To begin with,
+you'll need a Rainbows config file that tells it to use EventMachine, along with
+whatever Rainbows/Unicorn configuration you require.
+
+    # rainbows.conf
+    Rainbows! do
+      use :EventMachine
+    end
+
+You can then run your <tt>config.ru</tt> file from the command line. Again,
+<tt>Rack::Lint</tt> will complain unless you put the application in production
+mode.
+
+    rainbows config.ru -c path/to/rainbows.conf -E production -p 9292
+
+Rainbows also has a Ruby API for starting a server:
+
+    require 'rainbows'
+    require './app'
+    
+    rackup = Unicorn::Configurator::RACKUP
+    rackup[:port] = 9292
+    rackup[:set_listener] = true
+    options = rackup[:options]
+    options[:config_file] = 'path/to/rainbows.conf'
+    
+    server = Rainbows::HttpServer.new(App, options)
+    
+    # This is non-blocking; use server.start.join to block
+    server.start
+
+
+=== Running the app with Goliath
+
+Goliath can be made to run arbitrary Rack apps by delegating to them from a
+<tt>Goliath::API</tt> instance. A simple server looks like this:
+
+    require 'goliath'
+    require './app'
+    
+    class EchoServer < Goliath::API
+      def response(env)
+        App.call(env)
+      end
+    end
+
+<tt>Faye::WebSocket</tt> can also be used inline within a Goliath app:
+
+    require 'goliath'
+    require 'faye/websocket'
+    
+    class EchoServer < Goliath::API
+      def response(env)
+        ws = Faye::WebSocket.new(env)
+        
+        ws.onmessage = lambda do |event|
+          ws.send(event.data)
+        end
+        
+        ws.rack_response
+      end
+    end
+
+
 == License
 
 (The MIT License)
 
-Copyright (c) 2009-2011 James Coglan
+Copyright (c) 2009-2012 James Coglan
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the 'Software'), to deal in
 the Software without restriction, including without limitation the rights to use,
 copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the