Class: HTTTee::Server::SSE::Middleware

Inherits:
Object
  • Object
show all
Defined in:
lib/htttee/server/sse/middleware.rb

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ Middleware

Returns a new instance of Middleware.



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# File 'lib/htttee/server/sse/middleware.rb', line 5

def initialize(app)
  @app = app
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/htttee/server/sse/middleware.rb', line 9

def call(env)
  if sse_request?(env)
    wrap(env)
  elsif sse_supported?(env)
    return sse_shell
  end

  @app.call(env)
end

#sse_request?(env) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/htttee/server/sse/middleware.rb', line 29

def sse_request?(env)
  env['HTTP_ACCEPT'] == 'text/event-stream'
end

#sse_shell ⇒ Object 



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# File 'lib/htttee/server/sse/middleware.rb', line 38

def sse_shell
  [200, {'Content-Type' => 'text/html'}, [<<-HTML]]
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8" />
  <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script>
</head>
<body><pre><code></code></pre>
  <script>
    var source = new EventSource(window.location.pathname);
    var body = $("html,body");
    var cursor = $("pre code")[0];
    var resetLine = false;

    function append(data) {
      if(resetLine == true) {
cursor.innerHTML = data;
      } else {
cursor.innerHTML += data;
      }

      resetLine = false;
    }

    source.onmessage = function(e) {
      append(e.data);
    };

    source.onerror = function(e) {
      console.log(e);
    };

    source.addEventListener('ctrl', function(e) {
      if(e.data == 'newline') {
append("\\n");
cursor = $("<code></code>").insertAfter(cursor)[0];
      } else if(e.data == 'crlf' || e.data == 'carriage-return') {
resetLine = true;
      } else if(e.data == 'eof') {
source.close();
      } else {
console.log(e);
      }
    }, false);

    window.setInterval(function(){
      window.scrollTo(0, document.body.scrollHeight);
    }, 100);

  </script>
</body>
</html>
  HTML
end

#sse_supported?(env) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/htttee/server/sse/middleware.rb', line 33

def sse_supported?(env)
  env['HTTP_USER_AGENT'].to_s =~ /WebKit/ &&
    env['HTTP_ACCEPT'] =~ %r{text/html}
end

#wrap(env) ⇒ Object 



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# File 'lib/htttee/server/sse/middleware.rb', line 19

def wrap(env)
  env['rack.response_body'] = SSE::Body.new(env['rack.response_body'])

  cb = env['async.callback']

  env['async.callback'] = lambda do |(status, headers, body)|
    cb.call([status, headers.merge('Content-Type' => 'text/event-stream', 'Connection' => 'Keep-Alive'), body])
  end
end