tlewin/chat.rb

## chat.rb
#!/usr/bin/env ruby -I ../lib -I lib
# coding: utf-8
require 'rtoken'
require 'json'

require 'sinatra/base'
require 'thin'

class Chat < Sinatra::Base

  enable :inline_templates

  @@connections = {}

  def self.start_timers
    # send alive signal
    EM.add_periodic_timer(5) do
      @@connections.each_pair do |k, v|
        h = {alive: true, conn_id: k}
        v[:connection] << "data: #{h.to_json}\n\n"
      end
    end

    # clear dead connections
    EM.add_periodic_timer(10) do
      now = Time.now
      @@connections.each_pair do |k, v|
        if now - v[:last_activity] >= 10
          v[:connection].close
          @@connections.delete(k)
        end
      end
    end
  end

  get '/' do
    halt erb(:login) unless params[:user]
    erb :chat, :locals => { :user => params[:user].gsub(/\W/, '') }
  end

  get '/stream', :provides => 'text/event-stream' do
    stream :keep_open do |out|
      conn_id = RToken.rtoken(size: 8, lowercase: true)
      @@connections[conn_id] = {
        :connection => out,
        :last_activity => Time.now
      }
      out.callback { @@connections.delete(conn_id) }
    end
  end

  post '/' do
    if params[:alive]
      conn_id = params[:alive]
      conn    = @@connections[conn_id]
      conn[:last_activity] = Time.now if conn
    else
      json = {msg: params[:msg]}.to_json
      @@connections.each_pair do |k, v|
        v[:connection] << "data: #{json}\n\n"
      end
    end
    204 # response without entity body
  end
end

EM.run do
  Thin::Server.start Chat, 'localhost', 4567
  Chat.start_timers
end

__END__

@@ layout
<html>
  <head>
    <title>Super Simple Chat with Sinatra</title>
    <meta charset="utf-8" />
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
  </head>
  <body><%= yield %></body>
</html>

@@ login
<form action='/'>
  <label for='user'>User Name:</label>
  <input name='user' value='' />
  <input type='submit' value="GO!" />
</form>

@@ chat
<pre id='chat'></pre>
<form>
  <input id='msg' placeholder='type message here...' />
</form>

<script>
  // reading
  var es = new EventSource('/stream');
  es.onmessage = function(e) {
    // ask if the connection is alive
    data = JSON.parse(e.data)
    if(data.alive) {
      $.post('/', {alive: data.conn_id});
    } else {
      $('#chat').append(data.msg + "\n")
    }
  };

  // writing
  $("form").on('submit',function(e) {
    $.post('/', {msg: "<%= user %>: " + $('#msg').val()});
    $('#msg').val(''); $('#msg').focus();
    e.preventDefault();
  });
</script>
	#!/usr/bin/env ruby -I ../lib -I lib
	# coding: utf-8
	require 'rtoken'
	require 'json'

	require 'sinatra/base'
	require 'thin'

	class Chat < Sinatra::Base

	enable :inline_templates

	@@connections = {}

	def self.start_timers
	# send alive signal
	EM.add_periodic_timer(5) do
	@@connections.each_pair do \|k, v\|
	h = {alive: true, conn_id: k}
	v[:connection] << "data: #{h.to_json}\n\n"
	end
	end

	# clear dead connections
	EM.add_periodic_timer(10) do
	now = Time.now
	@@connections.each_pair do \|k, v\|
	if now - v[:last_activity] >= 10
	v[:connection].close
	@@connections.delete(k)
	end
	end
	end
	end

	get '/' do
	halt erb(:login) unless params[:user]
	erb :chat, :locals => { :user => params[:user].gsub(/\W/, '') }
	end

	get '/stream', :provides => 'text/event-stream' do
	stream :keep_open do \|out\|
	conn_id = RToken.rtoken(size: 8, lowercase: true)
	@@connections[conn_id] = {
	:connection => out,
	:last_activity => Time.now
	}
	out.callback { @@connections.delete(conn_id) }
	end
	end

	post '/' do
	if params[:alive]
	conn_id = params[:alive]
	conn = @@connections[conn_id]
	conn[:last_activity] = Time.now if conn
	else
	json = {msg: params[:msg]}.to_json
	@@connections.each_pair do \|k, v\|
	v[:connection] << "data: #{json}\n\n"
	end
	end
	204 # response without entity body
	end
	end

	EM.run do
	Thin::Server.start Chat, 'localhost', 4567
	Chat.start_timers
	end

	__END__

	@@ layout
	<html>
	<head>
	<title>Super Simple Chat with Sinatra</title>
	<meta charset="utf-8" />
	<script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
	</head>
	<body><%= yield %></body>
	</html>

	@@ login
	<form action='/'>
	<label for='user'>User Name:</label>
	<input name='user' value='' />
	<input type='submit' value="GO!" />
	</form>

	@@ chat
	<pre id='chat'></pre>
	<form>
	<input id='msg' placeholder='type message here...' />
	</form>

	<script>
	// reading
	var es = new EventSource('/stream');
	es.onmessage = function(e) {
	// ask if the connection is alive
	data = JSON.parse(e.data)
	if(data.alive) {
	$.post('/', {alive: data.conn_id});
	} else {
	$('#chat').append(data.msg + "\n")
	}
	};

	// writing
	$("form").on('submit',function(e) {
	$.post('/', {msg: "<%= user %>: " + $('#msg').val()});
	$('#msg').val(''); $('#msg').focus();
	e.preventDefault();
	});
	</script>