Mailman 3 November 2007 - Twisted

[Twisted-Python] twisted framework for multiple application server herd?
by lemon tea Nov. 28, 2007

Nov. 28, 2007

let's assume that we are building a new Wikimedia-style service where (1) updates to articles will happen far more often and (2) access will be required via various protocols, not just HTTP. In this new service the application server looks like it will be a bottleneck. From a software point of view our application will turn into too much of a pain to add nontraditional servers (e.g., for access via cell phones, where the cell phones are frequently broadcasting their GPS locations). From a systems point of view the response time looks like it will too slow because the Wikimedia application server is a central bottleneck. To solve this lets look at a different architecture called an "application server herd", where the multiple application servers communicate directly to each other as well as via the core database and caches. The interserver communications are designed for rapidly-evolving data (e.g., GPS-based locations) whereas the database server will still be used for more stable data that is less-often accessed or that requires transactional semantics. For example, you might have four application servers A, B, C, D such that A talks with B and C, and B and C talk with D, so that if a user's cell phone posts updates about its location to any one of the application servers then the other servers will learn of the change after one or two interserver transmissions, without having to talk to the database. how well Twisted is suited for this kind of application and how well will it really work in practice. In particular, how easy is it to write applications using Twisted, and how maintainable and reliable those applications will be?what might be the pros n cons of using twisted. any comments? cheers Pam --------------------------------- Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how.

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[Twisted-Python] Transfering a file through xml sockets
by Raj kumar Nov. 28, 2007

Nov. 28, 2007

Hi, I have a server-client application(by using twisted),communicating through xml sockets. can any one help me in transferring a file from server to client through xml sockets? At lest some references to how to use xml sockets in transferring data/files. Thank you in advance. RAJ..... Chat on a cool, new interface. No download required. Go to http://in.messenger.yahoo.com/webmessengerpromo.php

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[Twisted-Python] Re: glyph changed u'proxyForInterface should allow upcalls'
by Jonathan Lange Nov. 26, 2007

Nov. 26, 2007

On Nov 26, 2007 3:59 PM, <trac(a)twistedmatrix.com> wrote: > Ticket u'proxyForInterface should allow upcalls' changed by glyph <glyph(a)divmod.com>: > > In my experience, once one has a failing TODO test, the rest is easy, and there's no point in creating a second branch :). > Which is why we have 19 failing TODOs :)

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[Twisted-Python] Weekly Bug Summary
by exarkun＠twistedmatrix.com Nov. 25, 2007

Nov. 25, 2007

Bug summary ______________________ Summary for 2007-11-18 through 2007-11-25 Bugs opened: 19 Bugs closed: 11 Total open bugs: 1051 (+8) |== Type Changes |== Priority Changes |== Component Changes |Defect: +3 |Highest: -4 |Conch: +1 |Enhancement: +5 |High: +3 |Core: +5 |Task: +1 |Normal: +9 |Pb: +1 |Low: +1 |Release Management: +3 |Trial: +1 |Web: -2 New / Reopened Bugs ______________________ ===== Highest ===== [#2908] twistd report-profile option doesn't work anywore (opened by therve) (CLOSED, fixed) task core http://twistedmatrix.com/trac/ticket/2908 [#2920] Support for Decimal in twisted.spread.jelly (opened by james(a)tri-tech.com) enhancement pb http://twistedmatrix.com/trac/ticket/2920 [#2921] twistd profiling options needs to be tested (opened by therve) enhancement core http://twistedmatrix.com/trac/ticket/2921 [#2885] Automate version updating (goodly) (opened by radix) (CLOSED, fixed) enhancement release management http://twistedmatrix.com/trac/ticket/2885 ===== High ===== [#2912] manhole_ssh emits warnings on import (opened by glyph) defect core http://twistedmatrix.com/trac/ticket/2912 [#2913] twisted.internet.tcp.Port.startListening after stopListening rebinds the port but doesn't make it usable again (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/2913 [#2924] conch gmpy support doesn't work anymore (opened by therve) defect conch http://twistedmatrix.com/trac/ticket/2924 ===== Normal ===== [#2909] XXX Comment Policy (opened by jml) enhancement core http://twistedmatrix.com/trac/ticket/2909 [#2910] Provide tests for the ITestCase and IReporter interfaces and test all implementations against those (opened by jml) task trial http://twistedmatrix.com/trac/ticket/2910 [#2911] assertWarns demands that you set the stacklevel one higher than is helpful (opened by jml) defect trial http://twistedmatrix.com/trac/ticket/2911 [#2914] Memcache server (opened by therve) enhancement core http://twistedmatrix.com/trac/ticket/2914 [#2916] Tests should create their own temporary working directories, rather than relying on _trial_temp (opened by jml) enhancement trial http://twistedmatrix.com/trac/ticket/2916 [#2917] intermittent twisted.test.test_pbfailure.PBFailureTest.test_deferredSecurity failure on OS X (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/2917 [#2918] intermittent twisted.test.test_ssl.SpammyTLSTestCase.testUnTLS failure on OS X (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/2918 [#2919] Provide easily testable API for deprecating other APIs (opened by jml) enhancement core http://twistedmatrix.com/trac/ticket/2919 [#2922] web.ProxyClientFactory does not close request after sending error message (opened by lewq) (CLOSED, duplicate) defect web http://twistedmatrix.com/trac/ticket/2922 [#2923] admin/release-twisted expects zope tarballs under old names (opened by zooko) enhancement release management http://twistedmatrix.com/trac/ticket/2923 [#2925] Need first-class release documentation generation code (opened by radix) enhancement release management http://twistedmatrix.com/trac/ticket/2925 ===== Low ===== [#2915] Provide way of incrementing patch number with date-based versioning (opened by jml) enhancement release management http://twistedmatrix.com/trac/ticket/2915 Closed Bugs ______________________ ===== Highest ===== [#2506] Memcached client (opened by therve, closed by therve, fixed) enhancement core http://twistedmatrix.com/trac/ticket/2506 [#2908] twistd report-profile option doesn't work anywore (opened by therve, closed by therve, fixed) task core http://twistedmatrix.com/trac/ticket/2908 [#942 ] plugin unit tests should use directories beneath _trial_temp, not twisted/plugins/ (opened by exarkun, closed by therve, fixed) defect core http://twistedmatrix.com/trac/ticket/942 [#2885] Automate version updating (goodly) (opened by radix, closed by jml, fixed) enhancement release management http://twistedmatrix.com/trac/ticket/2885 [#2885] Automate version updating (goodly) (opened by radix, closed by jml, fixed) enhancement release management http://twistedmatrix.com/trac/ticket/2885 [#2883] Remove attributes and methods from IReporter that imply text output (opened by jml, closed by jml, fixed) enhancement trial http://twistedmatrix.com/trac/ticket/2883 [#238 ] Write tests for twisted.web.proxy (opened by itamarst, closed by therve, fixed) enhancement web http://twistedmatrix.com/trac/ticket/238 [#2739] explain, document, and test trial's compatibility requirements for other test tools (opened by glyph, closed by jml, fixed) enhancement trial http://twistedmatrix.com/trac/ticket/2739 [#2803] findFailure fails to find the correct failure in a more complicated case (opened by Peaker, closed by therve, fixed) defect core http://twistedmatrix.com/trac/ticket/2803 ===== Normal ===== [#2905] ReverseProxyResource adds an extra '/' which confuses the backend web server (opened by trohed, closed by therve, fixed) defect web http://twistedmatrix.com/trac/ticket/2905 [#2922] web.ProxyClientFactory does not close request after sending error message (opened by lewq, closed by therve, duplicate) defect web http://twistedmatrix.com/trac/ticket/2922 Ticket Lifetime Stats ______________________ Oldest open ticket - [#38] Should be a way to create documentation aliases (since 2003-07-12 16:08:03). Newest open ticket - [#2925] Need first-class release documentation generation code (since 2007-11-23 22:55:27). Mean open ticket age: 562 days, 0:39:32.376206. Median: 458 days, 9:54:02.964218. Standard deviation: 412 days, 18:57:38.634451. Interquartile range: 514 days, 15:06:00. Mean time between ticket creation and ticket resolution: 125 days, 22:53:00.623298. Median: 15 days, 13:27:30. Standard deviation is 231 days, 1:56:49.008256. The interquartile range is 137 days, 14:35:31. Mean time spent in review: 68 days, 3:02:44.987207. Median: 3 days, 20:59:56. Standard deviation: 157 days, 3:28:53.616287. Interquartile range: 29 days, 1:56:41. Mean number of times a ticket is reviewed: 2.08033826638. Median: 1 Standard deviation: 1.75626161316. Interquartile range: 1. Contributor Stats ______________________ In the last 4 weeks, 15 unique ticket reporters 5 unique ticket reviewers 7 unique ticket resolvers In the last 24 weeks, 61 unique ticket reporters 15 unique ticket reviewers 13 unique ticket resolvers In the last 48 weeks, 147 unique ticket reporters 17 unique ticket reviewers 22 unique ticket resolvers

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[Twisted-Python] connectionLost issue
by Mark Papazyan Nov. 23, 2007

Nov. 23, 2007

Hello, i'm currently writing distributed system consisted of several components, which have both input and output ports. To solve the initial startup problem i simply use the retry approach: as soon as my components are initialized the try to connect to their peers in a loop. The problem is that the connectionLost function is not called for each Factories independently, but stops callbacking as soon as my component receives an incoming connection (although, the function belongs to the class responsible for the outgoing connection). Thus, the component assumes it has found all its peers, although only incoming connection is initiated, not the outgoing. Is there a way to tell the framework to handle the connection lost events for each Factory/Protocol objects separately? The code is trivial: class InputSession(Factory): def start(self): reactor.listenTCP(self.port, self) def startedConnecting(self, connector): print 'Started to connect.' def buildProtocol(self, addr): print 'Connected.' self.connector = InputConnector(self) return self.connector def clientConnectionLost(self, connector, reason): print 'Lost connection. Reason:', reason def clientConnectionFailed(self, connector, reason): print 'Connection failed. Reason:', reason ################################################################################ class InputConnector(Protocol): def __init__(self, session): self.session = session def connectionMade(self): print "Connection established" def connectionLost(self, reason): print "Connection lost" def dataReceived(self, input_stream): print "Receiving: " + input_stream ################################################################################ class OutputConnector (Protocol): def __init__(self, session): self.session = session def sendStream(self, stream): self.transport.writeSomeData(stream) def clientConnectionLost(self, connector, reason): print 'Lost connection.'# Reason:', reason ################################################################################ class OutputSession(ClientFactory): def start(self): reactor.connectTCP(self.host, self.port, self) def buildProtocol(self, addr): print 'Connected.' self.curr_tries = 0 self.connector = OutputConnector(self) return self.connector def clientConnectionLost(self, connector, reason): print 'Lost connection.'# Reason:', reason self.curr_tries = self.curr_tries + 1 print "Trying to reconnect: %d" % self.curr_tries connector.connect() def clientConnectionFailed(self, connector, reason): print 'Connection failed.'# Reason:', reason self.curr_tries = self.curr_tries + 1 connector.connect() Best Regards, Mark Papazyan -- GMX FreeMail: 1 GB Postfach, 5 E-Mail-Adressen, 10 Free SMS. Alle Infos und kostenlose Anmeldung: http://www.gmx.net/de/go/freemail

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[Twisted-Python] Seeking freelance twisted programmer to work on museum exhibit ...
by Darran Edmundson Nov. 22, 2007

Nov. 22, 2007

We are looking for a friendly and talented Twisted programmer to work part-time on an interactive museum exhibit. Some background. "On April 29, 1903, at 4:10 a.m., 82 million tonnes of limestone crashed from the summit of Turtle Mountain and buried a portion of the sleeping town of Frank [Alberta] ... The primary cause of the Frank Slide was the mountain's unstable structure." Here's a good aerial photo of the mountain and slide debris: http://ess.nrcan.gc.ca/rrnh-rran/images/proj1_fig2.jpg Our exhibit, due to be deployed in January at the Frank Slide Interpretive Centre (white building adjacent to debris in above image), is tasked with the reason for the collapse. To do this, we have opted to use a virtual time-line with a 65" screen moving electronically along a 14ft (4m) industrial slide track. The visitor, kept back from the screen mechanism by a parallel guard rail, controls the screen position via a slideable block. The content, synced with the screen position, shows the 150 million-year formation of the mountain and its eventual collapse in 1903. The Twisted work involves ethernet interfacing with a Gemini GV6K hardware controller and PB communication with the pyObjC-based Quicktime display code. (An aside, we are also interested in logging visitor usage to a local or remote database.) As my Twisted experience is limited, I can only guess that we are looking at 40-80 hours of work in total. While the schedule is flexible, we do need to start coding ASAP to meet our first prototype deadline. Work is remote, connecting by VPN to the hardware in question. As the deployment platform is OS X, ideally the programmer would be using a Mac ... this isn't critical. If you're interested, please contact me directly (darran(a)edmstudio.com) with your resume/experience, hourly rate, and availability. Cheers, Darran. -- Darran Edmundson [darran(a)edmstudio.com] http://www.edmstudio.com

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[Twisted-Python] Using twisted with logging.handlers.sockethandler
by Doug Farrell Nov. 21, 2007

Nov. 21, 2007

Hi all, I've been using Python for awhile, but am new to Twisted. I'm trying to build a server to handle logging messages from multiple Python processes via the logging.handlers.sockethandler system. I've got some ideas how to go about it, but would like some guidance if anyone has some. One thing I'd like to know is how to handle messages that don't arrive all at once in the dataReceived() method of the protocol module. Thanks, Doug

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[Twisted-Python] This showed up in pygame-users@seul.org
by Laura Creighton Nov. 21, 2007

Nov. 21, 2007

Anybody want to come explain twisted to somebody who just wants to network his game? Alas pygame-users is not a mailman mailing list, and Activestate seems to have stopped archiving it in August, so there is no way I know of to read the whole thread. Laura ------- Forwarded Message Return-Path: owner-pygame-users(a)seul.org Delivery-Date: Wed Nov 21 14:37:43 2007 Return-Path: <owner-pygame-users(a)seul.org> To: pygame-users(a)seul.org Subject: Re: [pygame] Networking? In-Reply-To: <6e04113a0711210522s6b4d629y2c6be6b4a13fa0f3(a)mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_9402_16396364.1195651869700" hey, please forgive me for any stupid observations.....it's just that I've been avoiding testing Twisted because people seem to be of the opinion that it takes over the main loop. And they like having control over that. Can the main reactor be manipulated in such a way that it is not the main loop? ------- End of Forwarded Message

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[Twisted-Python] Problem setting up epollreactor on Leopard
by Raja Kapur Nov. 21, 2007

Nov. 21, 2007

I'm pretty new to the world of Twisted and Python. I'm having trouble setting up Twisted with epollreactor on Mac OS X Leopard, I downloaded the Twisted 2.5.0 tarball which contained all the components of Twisted. I installed the package using setup.py, everything seems to be working fine except epollreactor. When I do: from twisted.internet import epollreactor epollreactor.install() Python says: line 1, in <module> from twisted.internet import epollreactor ImportError: cannot import name epollreactor I tried Googling around and checking the mailing list archives without much luck, anyone have any suggestions or ideas? Thank you!

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[Twisted-Python] Windows Communication Foundation
by Pavel Nov. 20, 2007

Nov. 20, 2007

Hi all, has anyone developed services with Twisted that are to be consumed by clients based on Windows Communication Foundation? Paul

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