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How to serve Cramp :: Websocket and a regular Rack application on the same port?

I am trying to use the same port to serve regular HTTP traffic, as well as websocket HTML5 through Cramp (which is built on top of EventMachine) using Ruby 1.9.3 and Thin 1.3.1. Here is a minimal, self-sufficient example:

require 'thin'
require 'cramp'
require 'http_router'

Cramp::Websocket.backend = :thin

class SocketApp < Cramp::Action
  self.transport = :websocket

  on_start = :connected
  on_finish = :disconnected
  on_data = :message

  def connected
    puts 'Client connected'
  end
  def disconnected
    puts 'Client disconnected'
  end
  def message(msg)
    puts "Got message: #{msg}"
    render 'Here is your reply'
  end
end

class WebApp
  def call(env)
    [ 200, { 'Content-Type' => 'text/html' }, <<EOF
<html><head>
<script>
  function init() {
    function log(msg) { document.getElementById('log').innerHTML += msg + '<br>'; }
    var socketUri = 'ws://' + document.location.host + '/socket';
    log('Socket URI: ' + socketUri);
    var socket = new WebSocket(socketUri);
    socket.onopen = function(e) {
      log('onopen');
      socket.send('Is there anybody out there?');
      log('sent message');
    };
    socket.onclose = function(e) {
      log('onclose; code = ' + e.code + ', reason = ' + e.reason);
    };
    socket.onerror = function(e) {
      log('onerror');
    };
    socket.onmessage = function(e) {
      log('onmessage; data = ' + e.data);
    };
  }
</script>
</head><body onload='init();'>
  <h1>Serving Cramp::Websocket and normal Rack app on the same port</h1>
  <p id='log'></p>
</body></html>
EOF
    ]
  end
end

app = HttpRouter.new do
  add('/socket').to SocketApp
  add('/').to WebApp.new
end

run app

If you want to try this for yourself, paste this code into a file with a name config.ruand run it thin start. You need gems thin, crampand http_routerfor installation.

, JavaScript WebSocket ws://localhost:3000/socket, , , . open , , .

, Client connected .

thin start -D, , HTTP 101 , .

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. , HttpRouter thin , . , , HttpRouter WebApp.

+3
1

, , , , , : websocket-rack. :

require 'thin'
require 'http_router'
require 'rack/websocket'

class SocketApp < Rack::WebSocket::Application
  def on_open(env)
    puts 'Client connected'
  end
  def on_close(env)
    puts 'Client disconnected'
  end
  def on_message(env, message)
    puts "Got message: #{message}"
    send_data 'Here is your reply'
  end
end

class WebApp
  def call(env)
    [200, { 'Content-Type' => 'text/html' }, <<EOF
<html><head>
<script>
  function init() {
    function log(msg) { document.getElementById('log').innerHTML += msg + '<br>'; }
    var socketUri = 'ws://' + document.location.host + '/socket';
    log('Socket URI: ' + socketUri);
    var socket = new WebSocket(socketUri);
    socket.onopen = function(e) {
      log('onopen');
      socket.send('Is there anybody out there?');
      log('sent message');
    };
    socket.onclose = function(e) {
      log('onclose; code = ' + e.code + ', reason = ' + e.reason);
    };
    socket.onerror = function(e) {
      log('onerror');
    };
    socket.onmessage = function(e) {
      log('onmessage; data = ' + e.data);
    };
  }
</script>
</head><body onload='init();'>
  <h1>Serving WebSocket and normal Rack app on the same port</h1>
  <p id='log'></p>
</body></html>
EOF
    ]
  end
end

app = HttpRouter.new do
  add('/socket').to(SocketApp.new)
  add('/').to(WebApp.new)
end

run app
+3

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