Mailman 3 September 2007 - Twisted

[Twisted-Python] Reconnecting PB Client
by Don Smith 12 Sep '07

12 Sep '07

Does anyone have some example code for building a reconnecting PB client? This is what I have now: from twisted.spread import pb from twisted.internet import reactor from twisted.python import util events = pb.PBClientFactory() reactor.connectTCP("localhost", 8789, events) queue = events.getRootObject()

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[Twisted-Python] The Reactor
by Terry Jones 12 Sep '07

12 Sep '07

Word leaks that the Google Reader coders call their back-end "Reactor". http://blogoscoped.com/archive/2007-09-11-n21.html One wonders. Terry

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[Twisted-Python] trial on specific directory
by Nathaniel Haggard 12 Sep '07

12 Sep '07

How do I tell trial to test the code in /mydir with the /mydir/test/test_class1 instead testing the code from /lib/site-packages like it does by default. Thanks, Nate

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Re: [Twisted-Python] Wrapping a Perspective
by Andrew Francis 11 Sep '07

11 Sep '07

Hi Rasjid: > It might be possible to create a new twisted reactor > that integrates into the python com server event >loop. That would presumably be the correct way to >deal with this. But that would seem like far more work > that I have time to devote to this problem at this > time. Hopefully, I understood your problem correctly... If you are willing to use Stackless Python, I would recommend you use Christopher Armstrong's threadlesss.py blockOn function. This would allow Twisted calls to block. A few months ago, I posted a solution that would work, but it would be overkill. I am also curious why you can't use inline callbacks? If I can find the time, I will post an example. > So my question really is: > What are the problems / brawbacks with running the > twisted reactor in > a non-main thread, provided all calls to the reactor > are done through > twisted.internet.blockingCallFromThread? I have used threads with Twisted and Stackless and found I took a performance hit. Also I found it prudent to heed the advice and try not to mix threads with Twisted (or Stackless) Cheers, Andrew ____________________________________________________________________________________ Fussy? Opinionated? Impossible to please? Perfect. Join Yahoo!'s user panel and lay it on us. http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7

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[Twisted-Python] epoll reactor in Twisted 2.50 tarball
by Alvin Delagon 10 Sep '07

10 Sep '07

Hello guys, I have to install Twisted 2.50 on our Ubuntu Dapper servers. The problem is that I have to use the Twisted 2.50 tarball since Dapper apt repositories only have Twisted 2.40. The installation went smoothly and my twisted applications works except that when I try to run my scripts using the epoll reactor (twistd -ny ./myscript -r epoll) I get this error. Traceback (most recent call last): File "/usr/bin/twistd", line 21, in ? run() File "/usr/lib/python2.4/site-packages/twisted/scripts/twistd.py", line 27, in run app.run(runApp, ServerOptions) File "/usr/lib/python2.4/site-packages/twisted/application/app.py", line 374, in run config.parseOptions() File "/usr/lib/python2.4/site-packages/twisted/application/app.py", line 354, in parseOptions usage.Options.parseOptions(self, options) File "/usr/lib/python2.4/site-packages/twisted/python/usage.py", line 177, in parseOptions self.__dispatch[optMangled](optMangled, arg) File "/usr/lib/python2.4/site-packages/twisted/python/usage.py", line 333, in <lambda> fn = lambda name, value, m=method: m(value) File "/usr/lib/python2.4/site-packages/twisted/application/app.py", line 276, in opt_reactor installReactor(shortName) File "/usr/lib/python2.4/site-packages/twisted/application/reactors.py", line 80, in installReactor installer.install() File "/usr/lib/python2.4/site-packages/twisted/application/reactors.py", line 60, in install namedAny(self.moduleName).install() File "/usr/lib/python2.4/site-packages/twisted/python/reflect.py", line 357, in namedAny topLevelPackage = __import__(trialname) File "/usr/lib/python2.4/site-packages/twisted/internet/epollreactor.py", line 22, in ? from twisted.python import _epoll ImportError: cannot import name _epoll On my workstation (LinuxMint 3.0), the epoll reactor works fine. The difference is that I installed Twisted via apt-get. Thanks in advance for anyone who can point me to the right way. --- Alvin Delagon

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[Twisted-Python] How to ... in Conch?
by Konrads Smelkovs 09 Sep '07

09 Sep '07

1) I want to invoke(exec) a command with arguments from a SSH Conch client. The example suggests that arguments should be passed along with command, so to invoke 'ls -l', one would pass common.NS('ls -l'). What to do about arguments that have spaces? Should I slash-escape them? 2) How to obtain the retcode from an exec'ed command? -- Konrads Smelkovs Applied IT sorcery.

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[Twisted-Python] twistd doesn't work
by David Langford 09 Sep '07

09 Sep '07

Hey everyone I'm going through the finger tutorial -> http://twistedmatrix.com/projects/core/documentation/howto/tutorial/intro.h…. And at the end of the first section it talks about using the twistd command. Now it just plain doesn't work for me, telling me the command is not found. I'm using a macbook pro and i type the command into terminal. Can anyone tell me what i'm doing wrong. Because the next section doesn't work (i'm assuming its related to my lack of twistd-ness) I know this a n00bish question, and i've been searching for an answer, but everyone else seems to be able to get it working and no one mentions having problems. Then i thought maybee i have to download something extra for twisted, but a search of the site only returned tickets (bug tickets) instead of an actual search of the site. Any help would be greatly appreciated Lango

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[Twisted-Python] Weekly Bug Summary
by exarkun＠twistedmatrix.com 08 Sep '07

08 Sep '07

Bug summary ______________________ Summary for 2007-09-02 through 2007-09-09 Bugs opened: 19 Bugs closed: 7 Total open bugs: 1036 (+12) |== Type Changes |== Priority Changes |== Component Changes |Defect: +7 |Highest: +1 |Core: +7 |Enhancement: +7 |High: +0 |Ftp: -1 |Task: +1 |Normal: +14 |Trial: +3 |Vfs: +6 New / Reopened Bugs ______________________ ===== Highest ===== [#2811] eliminate shared mutable state from reactor implementations (opened by exarkun) (CLOSED, fixed) enhancement core http://twistedmatrix.com/trac/ticket/2811 [#2821] create twistd plugin for vfs (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2821 [#1264] twisted.vfs.test.test_ftp is enough to drive a sane man mad (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/1264 ===== High ===== [#2822] deprecate twisted.python.reflect.filenameToModuleName so that it can be removed (opened by exarkun) task core http://twistedmatrix.com/trac/ticket/2822 ===== Normal ===== [#2812] cfreactor replacement using threadedselectreactor (opened by termie) enhancement core http://twistedmatrix.com/trac/ticket/2812 [#2813] logstr initialization should happen before calling makeConnection in tcp.BaseClient (opened by therve) enhancement core http://twistedmatrix.com/trac/ticket/2813 [#2814] bugfix in epollreactor.py: sometime event cann't be identified when connection is lost (opened by huyx) (CLOSED, duplicate) defect core http://twistedmatrix.com/trac/ticket/2814 [#2815] Update VFS backends to an async interface (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2815 [#2816] Port the vfs ftp adapter to new async backends (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2816 [#2817] Port the vfs sftp adapter to new async backends (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2817 [#2818] Port the vfs stream adapter to new async backends (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2818 [#2819] Delete old sync vfs code and cleanup (opened by cablehead) enhancement vfs http://twistedmatrix.com/trac/ticket/2819 [#2820] trial warning reporting uses print to stdout (opened by exarkun) defect trial http://twistedmatrix.com/trac/ticket/2820 [#2823] trial path/to/package// fails immediately with AssertionError (opened by exarkun) defect trial http://twistedmatrix.com/trac/ticket/2823 [#2824] spawnProcess and screen -D -m not getting along (opened by TTimo) defect core http://twistedmatrix.com/trac/ticket/2824 [#2825] reactors handle case where socket.fileno() returns -1 (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/2825 [#2826] twisted.internet.tcp.Server.repstr wrong when listening on port 0 (opened by exarkun) defect core http://twistedmatrix.com/trac/ticket/2826 [#2188] Trial catches exceptions during import (opened by jdahlin) defect trial http://twistedmatrix.com/trac/ticket/2188 [#2735] twisted.vfs.adapters.ftp._FileToConsumerAdapter doesn't fully implement IConsumer (opened by therve) defect vfs http://twistedmatrix.com/trac/ticket/2735 Closed Bugs ______________________ ===== Highest ===== [#1904] Passive port ranges are not settable in t.p.ftp (opened by krp, closed by therve, fixed) enhancement ftp http://twistedmatrix.com/trac/ticket/1904 [#2811] eliminate shared mutable state from reactor implementations (opened by exarkun, closed by exarkun, fixed) enhancement core http://twistedmatrix.com/trac/ticket/2811 [#1264] twisted.vfs.test.test_ftp is enough to drive a sane man mad (opened by exarkun, closed by therve, ) defect core http://twistedmatrix.com/trac/ticket/1264 ===== High ===== [#1223] vfs methods should always return deferreds (opened by cablehead, closed by cablehead, duplicate) defect vfs http://twistedmatrix.com/trac/ticket/1223 ===== Normal ===== [#2188] Trial catches exceptions during import (opened by jdahlin, closed by exarkun, ) defect trial http://twistedmatrix.com/trac/ticket/2188 [#2814] bugfix in epollreactor.py: sometime event cann't be identified when connection is lost (opened by huyx, closed by therve, duplicate) defect core http://twistedmatrix.com/trac/ticket/2814 [#2735] twisted.vfs.adapters.ftp._FileToConsumerAdapter doesn't fully implement IConsumer (opened by therve, closed by therve, ) defect vfs http://twistedmatrix.com/trac/ticket/2735 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 - [#2826] twisted.internet.tcp.Server.repstr wrong when listening on port 0 (since 2007-09-08 18:59:55). Mean open ticket age: 511 days, 13:38:27.598094. Median: 408 days, 23:27:57.886705. Standard deviation: 400 days, 13:51:14.700782. Interquartile range: 502 days, 7:38:45. Mean time between ticket creation and ticket resolution: 120 days, 23:56:32.985168. Median: 14 days, 8:13:35. Standard deviation is 224 days, 18:24:36.530891. The interquartile range is 127 days, 8:11:35. Mean time spent in review: 64 days, 0:26:37.767588. Median: 4 days, 0:03:10. Standard deviation: 140 days, 6:05:08.850661. Interquartile range: 29 days, 11:02:35. Mean number of times a ticket is reviewed: 1.93571428571. Median: 1 Standard deviation: 1.57000476623. Interquartile range: 1. Contributor Stats ______________________ In the last 4 weeks, 18 unique ticket reporters 6 unique ticket reviewers 6 unique ticket resolvers In the last 24 weeks, 81 unique ticket reporters 14 unique ticket reviewers 14 unique ticket resolvers In the last 48 weeks, 157 unique ticket reporters 19 unique ticket reviewers 27 unique ticket resolvers

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Re: [Twisted-Python] Wrapping a Perspective
by Andrew Francis 07 Sep '07

07 Sep '07

Hi Rasjid: >I have read about Stackless, and it looks like it >would be really fun to play with. But I don't think my employer would be keen to go as 'fringe' as Stackless. Once you get the swing of it, Stackless Python is pretty fun... and powerful. Even more fun when one figures out how to properly integrate Stackless Python with Twisted. Anyhow I haven't played with the Perspective Broker before. So I read the Bruce Eckel "Grokking Twisted" article and wrote a simple example to illustrate how to make Twisted inter-operate with Stackless. The essense of the solution is the approach Armstrong takes in threadless.py. I provide a bit more syntactic sugaring: 1) Use a proxy that slightly modifies the method calls, mainly to hide the underlying deferred. 2) trigger a "TwistedException." example fragment: def execute(self, host, port): global flag factory = pb.PBClientFactory() log.msg("connecting") reactor.connectTCP(host, port, factory) log.msg("connected") try: perspective = self.processor.getRootObject(factory) print "=>", processor.calculate(perspective, 10, 20) flag = False except TwistedException: log.msg("A Twisted Exception was thrown") log.msg(sys.exc_info()) One of my long term goals is to standardise the approach and auto generate proxies and exceptions as to make Twisted safe for the average Stackless Python programmer. Cheers, Andrew P.S - reference http://www.artima.com/weblogs/viewpost.jsp?thread=156396 PBServer.py - is Bruce Eckel's server slightly modified. ____________________________________________________________________________________ Got a little couch potato? Check out fun summer activities for kids. http://search.yahoo.com/search?fr=oni_on_mail&p=summer+activities+for+kids&…

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Re: [Twisted-Python] Properly handling Connection Refused
by Beau Hargis 05 Sep '07

05 Sep '07

That small script worked as it should. The traceback is exactly the same as in my application. I just wonder where the '[Uninitialized]' is coming from. How is it ending up like that? Is it getting garbage collected for some reason? I can't catch the state of the port fast enough to see if it's anything else in the stack. I am using the poll reactor. I will change it back to the default select reactor and see if I see a problem with it again and see what other tracing I can do. ----- Original Message ---- From: Jean-Paul Calderone <exarkun(a)divmod.com> To: Twisted general discussion <twisted-python(a)twistedmatrix.com> Sent: Wednesday, September 5, 2007 12:54:31 PM Subject: Re: [Twisted-Python] Properly handling Connection Refused On Wed, 5 Sep 2007 12:37:16 -0700 (PDT), Beau Hargis <beau(a)subobscur.us> wrote: >Well, it subclasses 'protocol.ClientFactory'. I did not try 'ReconnectingClientFactory' yet as I wanted a little bit more control of the reconnecting process at some point. In any case, these functions are defined in the class as such: > > def clientConnectionFailed(self, connector, reason): > print 'Connection failed. Reason: ', reason > reactor.callLater(random.randint(10,91), connector.connect) > > def clientConnectionLost(self, connector, reason): > print 'Connection Lost. Reason: ', reason > reactor.callLater(random.randint(10,91), connector.connect) > >Works ok for every other problem except Connection Refused. When I first started testing reconnect, the seconds argument to callLater was constant like 3 or 4 seconds and it did the same thing. Even immediate reconnection caused the same problem with Connection Refused: 111. This looks as though it should work. If I run a similar test program, like this: from twisted.internet.protocol import ClientFactory, Protocol from twisted.internet import reactor class Reconnecter(ClientFactory): def clientConnectionFailed(self, connector, reason): print reason reactor.callLater(5, connector.connect) reactor.connectTCP('localhost', 12345, Reconnecter()) reactor.run() where nothing is bound to localhost:12345, then I see a connection refused message every five seconds for as long as I allow it to run. Can you see if this simple program exhibits the same behavior as your application? It would also be worth determining if your application is receiving the clientConnectionFailed notification but then failing to attempt another connection (ie, some problem with the callLater), if it is attempting the next connection but that is never happening (ie, some problem with the connector.connect), or if clientConnectionFailed isn't even being called for the connection which is failing (some problem inside the reactor with failed connection detection/notification). If you can, it would also be useful to know what the operating system thinks the state of the socket used for the connection attempt is. On Linux, you can get this with a tool like netstat. Jean-Paul _______________________________________________ Twisted-Python mailing list Twisted-Python(a)twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python

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