Mailman 3 December 2009 - Twisted

[Twisted-Python] Websites down
by Landreville 21 Dec '09

21 Dec '09

I'm getting an error from http://twistedmatrix.com Error 503 Service Unavailable Service Unavailable Guru Meditation: XID: 1274684191 Varnish

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Re: [Twisted-Python] A resizable cooperator class for queuing and dispatching jobs
by Terry Jones 21 Dec '09

21 Dec '09

I forgot to mention that I put the code for this class onto Launchpad: https://launchpad.net/txrdq Terry

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[Twisted-Python] Weekly Bug Summary
by exarkun＠twistedmatrix.com 20 Dec '09

20 Dec '09

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[Twisted-Python] Memcache client issues
by MārisR 19 Dec '09

19 Dec '09

Hello! I'm trying to write small tcp server, which doing some stuff with memcache. Everything was fine until I start it on production, after few minutes I got to rollback to old one. My script got max open files limit :( After liitle inspection, I saw that, new connection to my daemon opens new connection to memcache and after disconnect its not closed and on new connections is not reused. I could not find how to disconnect form memcache after processing is done, or how to reuse open connections. Maybe someone has some good example of this? Thanks!

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[Twisted-Python] copy.deepcopy domish.Element works in python 2.5 but not in 2.6
by Gabriel Rossetti 18 Dec '09

18 Dec '09

Hello everyone, for some reason copy.deepcopy forks great on a domish.Element on 2.5 but not in 2.6 : Python 2.5.4 (r254:67916, Sep 20 2009, 10:05:43) [GCC 4.4.1] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> from twisted.words.xish import domish >>> import copy >>> msg = domish.Element(('jabber:client', 'message')) >>> msg2 = copy.deepcopy(msg) >>> Python 2.6.4 (r264:75706, Nov 2 2009, 14:38:03) [GCC 4.4.1] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> from twisted.words.xish import domish >>> import copy >>> msg = domish.Element(('jabber:client', 'message')) >>> msg2 = copy.deepcopy(msg) Exception RuntimeError: 'maximum recursion depth exceeded while calling a Python object' in <type 'exceptions.AttributeError'> ignored >>> does someone understand why? I'm using twisted 8.2 on ubuntu 9.10. Thank you, Gabriel

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[Twisted-Python] plugin system
by César García 18 Dec '09

18 Dec '09

Guys, I'am new to twisted and I've read the documentation about the plugin system and the components but I can't make it, I really do not get it well, do you guys have any examples there to see if I can get it :) Thanks a lot -- http://celord.blogspot.com/

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[Twisted-Python] Downpour - new project using Twisted
by Jeremy Jongsma 18 Dec '09

18 Dec '09

I just posted my latest project - Downpour, a web-based BitTorrent client using twisted and twisted-web. Feel free to try it out and send me any comments. It hasn't been tested on Windows yet, so any trip reports for that would also be appreciated. http://home.jongsma.org/software/downpour/ Could someone add this to the "Projects Using Twisted" page? -j --

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[Twisted-Python] UDP crashes python.exe when using IOCPReactor
by Josh Albrecht 16 Dec '09

16 Dec '09

I've been struggling to move a large program over to IOCPReactor, but it is causing python.exe to crash on windows. I reduced the error to this program, which crashes almost immediately on all the machines I've tested it on. Am I doing something wrong? ############################################# from twisted.internet.iocpreactor.reactor import IOCPReactor from twisted.internet.main import installReactor from twisted.internet.protocol import DatagramProtocol reactor = IOCPReactor() installReactor(reactor) DATA = 'HELLO' REMOTE_IP = "127.0.0.1" REMOTE_PORT = 33351 class EchoDatagram(DatagramProtocol): def datagramReceived(self, datagram, addr): print((addr, datagram)) self.transport.write(datagram, addr) p1 = EchoDatagram() listening_port1 = reactor.listenUDP(6951, p1, interface='') p2 = EchoDatagram() listening_port2 = reactor.listenUDP(REMOTE_PORT, p2, interface=REMOTE_IP) def pointless_write(): p1.transport.write(DATA, (REMOTE_IP, REMOTE_PORT)) for i in xrange(10): f = open("temp1", "wb") f.write("Hi!") f.close() f = open("temp1", "rb") data = f.read() f.close() reactor.callLater(1, pointless_write) reactor.callLater(1, pointless_write) reactor.run() ############################################# This has been driving me crazy all day. Any insights would be greatly appreciated! Thanks, Josh Albrecht

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[Twisted-Python] zope.interface
by Jared Gisin 16 Dec '09

16 Dec '09

Is there a good document that explains why zope.interface is necessary to the twisted project? -Jared

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[Twisted-Python] complete producer/consumer example
by Benjamin Rutt 16 Dec '09

16 Dec '09

How does the below example look as a complete producer/consumer example? If it's well received, perhaps we can add it to the online documentation at http://twistedmatrix.com/documents/current/core/howto/producers.html in the "Further Reading" section? I always felt that the producer/consumer (a.k.a. high volume streaming) docs lacked a real example that users could download and run. #!/sw/external/python-2.6.1/bin/python """Serve as a sample implementation of a twisted producer/consumer system, with a simple TCP server which asks the user how many random integers they want, and it sends the result set back to the user, one result per line.""" import random from zope.interface import implements from twisted.internet import interfaces, reactor from twisted.internet.protocol import Factory from twisted.protocols.basic import LineReceiver class Producer: """Send back the requested number of random integers to the client.""" implements(interfaces.IPushProducer) def __init__(self, proto, cnt): self._proto = proto self._goal = cnt self._produced = 0 self._paused = False def pauseProducing(self): """When we've produced data too fast, pauseProducing() will be called (reentrantly from within resumeProducing's transport.write method, most likely), so set a flag that causes production to pause temporarily.""" self._paused = True print('pausing connection from %s' % (self._proto.transport.getPeer())) def resumeProducing(self): self._paused = False while not self._paused and self._produced < self._goal: next_int = random.randint(0, 10000) self._proto.transport.write('%d\r\n' % (next_int)) self._produced += 1 if self._produced == self._goal: self._proto.transport.unregisterProducer() self._proto.transport.loseConnection() def stopProducing(self): pass class ServeRandom(LineReceiver): """Serve up random data.""" def connectionMade(self): print('connection made from %s' % (self.transport.getPeer())) self.transport.write('how many random integers do you want?\r\n') def lineReceived(self, line): cnt = int(line.strip()) producer = Producer(self, cnt) self.transport.registerProducer(producer, True) producer.resumeProducing() def connectionLost(self, reason): print('connection lost from %s' % (self.transport.getPeer())) factory = Factory() factory.protocol = ServeRandom reactor.listenTCP(1234, factory) print('listening on 1234...') reactor.run() Use on the client: $ telnet localhost 1234 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. how many random integers do you want? 5 431 7201 3289 9604 6659 Connection closed by foreign host. $ Use on the server (observe how the server pauses production sometimes - this happens when a large data set is requested by the client): $ ./streaming.py listening on 1234... connection made from IPv4Address(TCP, '127.0.0.1', 54859) connection lost from IPv4Address(TCP, '127.0.0.1', 54859) connection made from IPv4Address(TCP, '127.0.0.1', 54864) pausing connection from IPv4Address(TCP, '127.0.0.1', 54864) pausing connection from IPv4Address(TCP, '127.0.0.1', 54864) pausing connection from IPv4Address(TCP, '127.0.0.1', 54864) pausing connection from IPv4Address(TCP, '127.0.0.1', 54864) connection lost from IPv4Address(TCP, '127.0.0.1', 54864) [...] Thanks. -- Benjamin Rutt

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