experiments_with_stomp_and_twisted.py

from twisted.internet import reactor, protocol, defer
from twisted.protocols import basic

class SimpleStompProtocol(protocol.Protocol):
  def connectionMade(self):
    self.connect("", "")
    
  def dataReceived(self, data):
    frame = self.unpackFrame(data)
    if(frame['cmd'] == 'CONNECTED'):
      self.subscribe("/topic/wego.com.hotel.search")
    elif(frame['cmd'] == 'MESSAGE'):
      print "Message Received:\n%s" % frame['body']
    else:
      pass

  def subscribe(self, topic):
    self.sendFrame("SUBSCRIBE", {'destination' : topic, 'ack' : 'auto'})
  
  def connect(self, username, password):
    self.sendFrame("CONNECT", {'login' : username, 'password' : password})

  def sendFrame(self, verb, headers = {}, body = ""):
    ary = [verb, "\n"]
    for k,v in headers.iteritems():
      ary.append("%s: %s\n" % (k,v))
    ary.append("content-length: %i\n" % len(str(body)))
    ary.append("content-type: text-plain; charset=UTF-8\n\n")
    ary.append(str(body))
    ary.append("\x00")
    self.transport.write("".join(ary))


  def unpackFrame(self, message):
    """Called to unpack a STOMP message into a dictionary.
    returned = {
      # STOMP Command:
      'cmd' : '...',
      # Headers e.g.
      'headers' : {
        'destination' : 'xyz', 'message-id' : 'some event',
      }
      'body' : '...1234...\x00',
    }
    """
    body = []
    returned = dict(cmd='', headers={}, body='')

    breakdown = message.split('\n')

    # Get the message command:
    returned['cmd'] = breakdown[0]
    breakdown = breakdown[1:]

    def headD(field):
      # find the first ':' everything to the left of this is a
      # header, everything to the right is data:
      index = field.find(':')
      if index:
        header = field[:index].strip()
        data = field[index+1:].strip()
        returned['headers'][header.strip()] = data.strip()

    def bodyD(field):
      field = field.strip()
      if field:
        body.append(field)

    # Recover the header fields and body data
    handler = headD
    for field in breakdown:
      if field.strip() == '':
        # End of headers, it body data next.
        handler = bodyD
        continue
      handler(field)

    # Stich the body data together:
    body = "".join(body)
    returned['body'] = body.replace('\x00', '')

    return returned


class SimpleStompClientFactory(protocol.ClientFactory):
  protocol = SimpleStompProtocol
  
  def __init__(self):
    self.deferred = defer.Deferred()  

  def clientConnectionLost(self, transport, reason):
    reactor.stop()
    
  def clientConnectionFailed(self, transport, reason):
    print reason.getErrorMessage()
    reactor.stop()
    

if __name__ == "__main__":
  port = 61613
  reactor.connectTCP('localhost', port, SimpleStompClientFactory())
  reactor.run()