Mailman 3 May 2005 - Twisted

Re: [Twisted-Python] cleanup in twisted
by Joachim Boomberschloss May 23, 2005

May 23, 2005

--- Bob Ippolito <bob(a)redivi.com> wrote: > > On May 22, 2005, at 8:46 AM, Joachim Boomberschloss > wrote: > > > I just jotted down a little mechanism for > cleaning-up > > in Twisted, and I wanted to see if: > > 1. other people think it's needed > > 2. other people manage to use it > > > > What this does is enable one to define a > __cleanup__ > > method which gets call either when the instance is > > deleted, or when … [View More]

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[Twisted-Python] Weekly Bug Summary
by James Y Knight May 23, 2005

May 23, 2005

Bug summary ______________________ Since 2005-05-09 15:24:45.360000: Bugs opened: 20 Bugs closed: 15 Total open bugs: 369 (+5) Urgent: 7 (-2) Bug: 149 (+2) Feature: 139 (+1) Wish: 74 (+4) New / Reopened Bugs ______________________ ==== Urgent ==== trial randomly exits prematurely for no good reason (1 week ago) CLOSED http://twistedmatrix.com/bugs/issue1036 opened by exarkun ==== Bug ==== [WEBSITE] http://twistedmatrix.com/documents/ … [View More]

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[Twisted-Python] twisted.plugin plugin framework
by Nathaniel Haggard May 23, 2005

May 23, 2005

1. What is/was the purpose of twisted.plugin? 2. "mypkg" is a directory containing __init__.py __init__.py contains: import twisted.plugin import zope.interface as z import twisted.plugin as p class Beta: z.implements(p.IPlugin) class Gamma: """This is the doc string""" __implements__ = p.IPlugin ----------------- Trying to load the package with getPlugins returns an empty generator as far as I can tell import twisted.plugin import mypkg l = twisted.plugin.… [View More]

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Re: [Twisted-Python] cleanup in twisted
by Joachim Boomberschloss May 23, 2005

May 23, 2005

--- Jp Calderone <exarkun(a)divmod.com> wrote: > On Mon, 23 May 2005 02:40:53 -0700 (PDT), Joachim > Boomberschloss <boomberschloss(a)yahoo.com> wrote: > > > >--- Bob Ippolito <bob(a)redivi.com> wrote: > >> > >> On May 22, 2005, at 8:46 AM, Joachim > Boomberschloss > >> wrote: > >> > >> > I just jotted down a little mechanism for > >> cleaning-up > >> > in Twisted, and I wanted to see if: … [View More]

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Re: [Twisted-Python] How to create a new service and listen on a new port?
by Eric Hsu May 23, 2005

May 23, 2005

2005/5/23, mark <mark(a)junklight.com>: > Ah, > > my mistake for not reading properly. :-) Never mind : ) > > I guess one answer is to run AnotherService on port 2 from the start. [snip] > then both services will be running and you can just service both > ports. I am not sure quite what you are trying to do but from the > comments in your code why do you not simply send the confirm message > back via the FooServer? > Well, I need to create the … [View More]

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[Twisted-Python] cleanup in twisted
by Joachim Boomberschloss May 22, 2005

May 22, 2005

Hi! I just jotted down a little mechanism for cleaning-up in Twisted, and I wanted to see if: 1. other people think it's needed 2. other people manage to use it What this does is enable one to define a __cleanup__ method which gets call either when the instance is deleted, or when the reactor shuts down. It can return a dereffed that delays the shutdown. The benefit is being able to define communication-related stuff in the cleanup method, which is not so useful to do in __del__. The current … [View More]implementation uses pyDispatcher, but it could easily be rewritten without it. Feedback is welcomed! Joe. #---------------------------------------------------------------------------------------------------- from twisted.internet import reactor, defer, task from dispatch import dispatcher, robustapply #---------------------------------------------------------------------------------------------------- class CleanUpper: # our pydispatcher cleanup event ABOUT_TO_SHUTDOWN = "*about to shutdown*" def __init__(self): self._deferreds_to_wait_for_before_shutdown = [] # register with twisted a special callback that # fires a pydispatcher event. reactor.addSystemEventTrigger('before', 'shutdown', self._shutdown_handler) def _shutdown_handler(self): """this simply dispatches a pydispatcher event""" results = dispatcher.send( signal = self.ABOUT_TO_SHUTDOWN, sender = self) # any deferred registered by cleanup handlers should be waited for dl = defer.DeferredList([response for handler, response in results if isinstance(response, defer.Deferred)]) return dl # PUBLIC METHODS -------------------------------------------------------------------------- def register(self, functionToRunBeforeShutdown): """makes the given function get called prior to communication infrastructure shutdown""" # register the given function with pydispatcher dispatcher.connect( functionToRunBeforeShutdown, signal = self.ABOUT_TO_SHUTDOWN, sender = self) #---------------------------------------------------------------------------------------------------- # create an instance of CleanUpper # and make its register method global _c = CleanUpper() register = _c.register unregister = _c.unregister #---------------------------------------------------------------------------------------------------- class Cleanuppable: """ Inherit from this if you want to do your cleanup before Twisted shuts down and not (only) when you get deleted. If you inherit from this do not implement __del__, only __cleanup__! """ def __init__(self): self._cleanuppable_state = "normal" # normal, deleted, or cleanupped self._cleanuppable_deferred = None # register cleanup method register(self._cleanuppable_internal_cleanup_handler) def _cleanuppable_apply_cleanup(self): if hasattr(self, "__cleanup__"): # call user-defined cleanup method return robustapply.robustApply(self.__cleanup__) def _cleanuppable_internal_cleanup_handler(self): try: if self._cleanuppable_state == "normal": return self._cleanuppable_apply_cleanup() if self._cleanuppable_state == "deleted" and self._cleanuppable_deferred is not None: return self._cleanuppable_deferred finally: self._cleanuppable_state = "cleanupped" def __del__(self): if self._cleanuppable_state == "normal": self._cleanuppable_state = "deleted" response = self._cleanuppable_apply_cleanup() if isinstance(response, defer.Deferred): self._cleanuppable_deferred = response #---------------------------------------------------------------------------------------------------- __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com [View Less]

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[Twisted-Python] Anyone seeing hanging of Twisted HTTPS servers?
by Mike C. Fletcher May 21, 2005

May 21, 2005

We've recently picked up 3 or 4 minute blocks on one of our servers. Wondering if anyone else has seen these. We have a "zombiechecker" script that downloads the front page of the web front-end every minute (restarting the entire server if it can't connect). After 20 or 30 minutes (sometimes a few hours) we see 3 or 4 of those checks queued, the connection has been accepted, but the server appears to be frozen (the reactor doesn't appear to be processing anything, neither web front-end or … [View More]

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[Twisted-Python] Twistd thread problem
by Jan Van Uytven May 21, 2005

May 21, 2005

Hi all, I coded an SMTP proxy that receives incoming e-mail requests and pushes the received e-mail onto a Queue were it is processed by a worker thread that finishes by sending the e-mail on to another SMTP server. The server part of the proxy was written in Twisted, but the worker thread uses smtplib to fire off the processed e-mails (I didn't know how to use the twisted smtp client in a thread). When I run the application using twistd -noy <appname>, it works great. When I try … [View More]to daemonize it (twistd -oy <appname>) the server part works, but the worker thread doesn't. It creates and then I suspect it immediately dies, as no error is returned upon creation. A debug of the queue reveals that the thread is not pulling items off it. A debugging statement placed at the top of the thread never runs, and the twistd log reports nothing wrong. I'm using reactor.callInThread to start the worker function. I tried running twistd --spew -oy <appname> and captured the log it produced. I did a filter for anything with 'thread' in it, this is the result: 2005/05/16 09:15 PDT [-] function ? in /usr/lib/python2.3/site-packages/twisted/python/threadpool.py, line 11 2005/05/16 09:15 PDT [-] function WorkerStop in /usr/lib/python2.3/site-packages/twisted/python/threadpool.py, line 23 2005/05/16 09:15 PDT [-] function init in /usr/lib/python2.3/site-packages/twisted/python/threadable.py, line 219 2005/05/16 09:15 PDT [-] function ThreadPool in /usr/lib/python2.3/site-packages/twisted/python/threadpool.py, line 31 2005/05/16 09:15 PDT [-] function ThreadSafeList in /usr/lib/python2.3/site-packages/twisted/python/threadpool.py, line 199 2005/05/16 09:15 PDT [-] function init in /usr/lib/python2.3/site-packages/twisted/python/threadable.py, line 219 2005/05/16 09:15 PDT [-] method __init__ of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method start of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method adjustPoolsize of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method _startSomeWorkers of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method callInThread of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method _startSomeWorkers of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method startAWorker of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] method __init__ of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] method __init__ of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] method _set_daemon of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] function currentThread in /usr/lib/python2.3/threading.py, line 669 2005/05/16 09:15 PDT [-] method isDaemon of threading._MainThread at -1214935060 2005/05/16 09:15 PDT [-] function Condition in /usr/lib/python2.3/threading.py, line 147 2005/05/16 09:15 PDT [-] method __init__ of threading._Condition at -1216567604 2005/05/16 09:15 PDT [-] method __init__ of threading._Condition at -1216567604 2005/05/16 09:15 PDT [-] method start of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] method _note of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] method run of threading.Thread at -1216568116 2005/05/16 09:15 PDT [-] method _worker of twisted.python.threadpool.ThreadPool at -1216569236 2005/05/16 09:15 PDT [-] function currentThread in /usr/lib/python2.3/threading.py, line 669 2005/05/16 09:15 PDT [-] function threadMailer in twisted-copyuser.py, line 201 2005/05/16 09:15 PDT [-] method acquire of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] method release of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] method acquire of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] method release of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] method acquire of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] method release of twisted.python.threadable._XLock at -1216639284 2005/05/16 09:15 PDT [-] function registerAsIOThread in /usr/lib/python2.3/site-packages/twisted/python/threadable.py, line 262 Why would the worker thread act differently with twistd daemonized? Any suggestions, advice, or hints would be welcome. Thanks, Jan -- Jan Van Uytven Computer Systems & Network Engineer Convergent Media Network wyvern(a)crm3.com Only in silence the word, only in dark the light, only in dying life: Bright the hawk's flight on the empty sky. - Ursula K. LeGuin, 'A Wizard of Earthsea' *** LEGAL STUFF *** This electronic message transmission, including any attached files, contains information which may be confidential and/or privileged. The information is intended to be for the SOLE use of the individual or entity named above. If you are not the intended recipient, be aware that any review, disclosure, copying, distribution or use of the contents of this information is prohibited. This message is not to be forwarded for any reason without prior consent of the sender. If you have received this electronic transmission in error, please notify the sender immediately by telephone (250) 386-4266 or by a 'reply to sender' only message and destroy all electronic and hard copies of the communication, including attachments, without reading or saving in any manner. [View Less]

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RE: [Twisted-Python] Alarm collection and display system?
by Henning.Ramm＠mediapro-gmbh.de May 20, 2005

May 20, 2005

>Let me restate the problem (in an oversimplified way, sorry about that) > - the ability for disparate systems scattered across the network to >push messages to interested consumers distributed across the network >in a (near) real-time fashion. I thought about using chat clients (IRC, twisted.words or the like) for that purpose, so that... - all error "producers" can just send messages to an chat server - all interested users just start their chat client - different workflows (= … [View More]

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[Twisted-Python] twisted and network condition testing
by Thomas Vander Stichele May 20, 2005

May 20, 2005

Hi, While working on Flumotion I've realized there are quite a few conditions in real-life networks that I need to deal with and my experience is fairly limited. What can I say, I lived in a perfect world before :) All sorts of things trip up our application: machine lockups (where the other end doesn't realize the connection is broken), temporary routing problems, adsl connections being dropped, ... After doing a lot of ad-hoc hacking to solve all those issues, I've realized I'd better … [View More]

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[Twisted-Python] ldaptor based LDAP server
by Andrzej Leszczynski May 19, 2005

May 19, 2005

Hi, I am looking for a Python barebones for a simple LDAP server project. It does not have to be Twisted based, but it would be wonderful if it is. I need a very simple server which is listening on some port and accepts following LDAP messages: -bind -search -unbind There are not going to be a actual LDAP database backend. All what happens is parsing above and reply with some simple content based on the some parameters from the request. I am just wondering with using ldaptor's protocol … [View More]

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[Twisted-Python] using yield in unittest.TestCase
by maitland＠vanu.com May 19, 2005

May 19, 2005

Hi all- I've been trying to unit test some code that uses a lot of generators and Callbacks, so I would like to be able yield my Callbacks and check them out. However, whenever I stick a yield in my test case (in a subclass of trial.unittest.TestCase), the test automatically passes and, as far as I can tell, doesn't actually get evaluated at all. Is this a known issue? Does anybody know of a way I can work around it? Thanks, -Maitland

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[Twisted-Python] Using form
by Alberto Trujillo May 19, 2005

May 19, 2005

Hello: I'm working with twisted since a few days ago, and although I have read the tutorial, still I have some question about the class Request. Well, I have implemented project.rpy that have a form and use the method post the send the information to commit.rpy. <form action="commit.rpy?action=""" + action + """&type=project&id=""" + projid + """ method="post"> <table align="center" width="750" border="0" cellpadding="3" cellspacing="1" bgcolor="#353535"> <tr&… [View More]

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Re: [Twisted-Python] Simpler twistedmatrix.com doc indexes
by Brendon Hogger May 18, 2005

May 18, 2005

> I'd like to see it focus on the core docs and perhaps > provide some form of preferred or recommended learning path. I agree, the problem is that I don't actually know what the best learning path would be. Any suggestions? - Brendon

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[Twisted-Python] pending twisted fixes
by Andrea Arcangeli May 17, 2005

May 17, 2005

Hello, These are the pending fixes for twisted that I'm maintaining on my tree. On the client side to still allow 1.3.0 I've a file called twisted_bugs.py and I import from there instead of twisted.* depending on twisted.copyright.version. I've found very easy to fix a single bug locally by cut-and-pasting a twisted function and by fixing it locally while still not altering the 2.0 behaviour, it's pratically a local 2.0 backport which lives in its own file. Perhaps this would have been a … [View More]better approach than an upgrade to 2.0 in the rogers.com incident. Hotfixes seems quite easy this way and sure less invasive than a full upgrade (i.e. no risk of API breakage and no annoyance to the sysadm). This is just a reminder just in case other incident happens that seems to require 2.0 upgrade. from twisted.copyright import version twisted_bug_workaround = False if '1.3.0' in version: twisted_bug_workaround = True from twisted.internet import reactor # to stop it if not twisted_bug_workaround: from twisted.protocols.basic import Int32StringReceiver from twisted.internet.protocol import ReconnectingClientFactory else: from cpushare.twisted_bugs import Int32StringReceiver from cpushare.twisted_bugs import ReconnectingClientFactory Full working example of the 1.3.0 hotfixes is available in the download section of my site. The transport.disconnecting was said not to be available for all twisted transports, but then it should be added to the others instead of my rejecting my patch with that argument (those basic.py protocols are broken without this fix, so it's better that they fail with a visible exception than subtly at runtime), or another method should be implemented to know if the transport has disconnected already. Keep up the great work, thanks! Index: Twisted/twisted/protocols/basic.py =================================================================== --- Twisted/twisted/protocols/basic.py (revision 13717) +++ Twisted/twisted/protocols/basic.py (working copy) @@ -166,9 +166,23 @@ """ return error.ConnectionLost('Line length exceeded') +class PauseProducer(object): + paused = False + def pauseProducing(self): + self.paused = True + self.transport.pauseProducing() -class LineReceiver(protocol.Protocol): + def resumeProducing(self): + self.paused = False + self.transport.resumeProducing() + self.dataReceived('') + + def stopProducing(self): + self.paused = True + self.transport.stopProducing() + +class LineReceiver(protocol.Protocol, PauseProducer): """A protocol that receives lines and/or raw data, depending on mode. In line mode, each line that's received becomes a callback to @@ -188,7 +202,6 @@ __buffer = '' delimiter = '\r\n' MAX_LENGTH = 16384 - paused = False def clearLineBuffer(self): """Clear buffered data.""" @@ -279,21 +292,8 @@ """ return self.transport.loseConnection() - def pauseProducing(self): - self.paused = True - self.transport.pauseProducing() - def resumeProducing(self): - self.paused = False - self.dataReceived('') - self.transport.resumeProducing() - - def stopProducing(self): - self.paused = True - self.transport.stopProducing() - - -class Int32StringReceiver(protocol.Protocol): +class Int32StringReceiver(protocol.Protocol, PauseProducer): """A receiver for int32-prefixed strings. An int32 string is a string prefixed by 4 bytes, the 32-bit length of @@ -314,7 +314,7 @@ """Convert int32 prefixed strings into calls to stringReceived. """ self.recvd = self.recvd + recd - while len(self.recvd) > 3: + while len(self.recvd) > 3 and not self.paused and not self.transport.disconnecting: length ,= struct.unpack("!i",self.recvd[:4]) if length > self.MAX_LENGTH: self.transport.loseConnection() @@ -331,7 +331,7 @@ self.transport.write(struct.pack("!i",len(data))+data) -class Int16StringReceiver(protocol.Protocol): +class Int16StringReceiver(protocol.Protocol, PauseProducer): """A receiver for int16-prefixed strings. An int16 string is a string prefixed by 2 bytes, the 16-bit length of @@ -351,7 +351,7 @@ """Convert int16 prefixed strings into calls to stringReceived. """ self.recvd = self.recvd + recd - while len(self.recvd) > 1: + while len(self.recvd) > 1 and not self.paused and not self.transport.disconnecting: length = (ord(self.recvd[0]) * 256) + ord(self.recvd[1]) if len(self.recvd) < length+2: break Index: Twisted/twisted/lore/latex.py =================================================================== --- Twisted/twisted/lore/latex.py (revision 13717) +++ Twisted/twisted/lore/latex.py (working copy) @@ -104,7 +104,7 @@ baseLevel = 0 try: - diaHack = not not os.popen('which dia').read() + diaHack = not not os.popen('which dia 2>/dev/null').read() except: # That's a no, then. diaHack = 0 [View Less]

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[Twisted-Python] Unit Testing in twisted 2.0
by Shawn Church May 17, 2005

May 17, 2005

I've been following the recent thread on the problems with twisted.trial and since it is evidently broken I am hesitant about using it. Instead I create a class that performs all of my tests and sets class attributes with the results. I can then create this class once (at the module level) and then use the standard unittest module to check the results. For example (this is untested code, I'm just trying to briefly illustrate the approach I'm taking): class PerformTests: def __init__(… [View More]

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[Twisted-Python] Simpler twistedmatrix.com doc indexes
by Brendon Hogger May 17, 2005

May 17, 2005

Hi there. I've been playing around with using lore and microdom to generate better indexes for the Twisted documentation, and also to move everything into a single /doc tree. The results, at least until I break it all again, are here: http://microdev.dyndns.org:8080/doc/ I'm looking for feedback on whether this is any easier to use, and what could be improved. There are some issues I already know about: - Links to non-html resources are broken - Core HOWTO list is gigantic and … [View More]

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[Twisted-Python] adbapi, PostgreSQL and Unicode
by Michal Eldar May 17, 2005

May 17, 2005

I keep getting - Unhandled error in Deferred I'm trying to perform an INSERT on my db (using adbapi with *pgdb* module). INSERT which comprises *Unicode* string e.g. - unicodeChar1 = u"Character=[\N{GREEK CAPITAL LETTER GAMMA}]" the db is defined to Unicode *client_encoding* value is set to *Unicode* when checking its value in *cp_openfun *called function execute the same INSERT directly with *pgdb *works great Does anyone has experience with adbapi with Unicode db ?!?! Do I need to define … [View More]

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[Twisted-Python] ldaptor examples failed + python-ldap examples with twisted
by jean-marc.pouchoulon＠ac-montpellier.fr May 17, 2005

May 17, 2005

Bonjour, I try to run ldaptor examples with python2.4.1 , twisted 2.0, nevow 0.4.1, fedora core 3. .05_form gives me "Deferred instance has no attribute 'original'" and some warnings. Does anyone has an updated code ? ( I used the latest code I've got from svn ) I search also python-ldap examples with twisted. Thanks. NB : Twisted 2.0 rc4 windows installer never finished on my PC... (french xp sp2)

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[Twisted-Python] Twisted projects
by Tim Terlegård May 15, 2005

May 15, 2005

What about having a page on twistedmatrix.com that shows projects based on Twisted? I think that would be really nice. A sourceforge for Twisted projects is perhaps a bit too much, a simple listing of projects would be nice. Would be great if people could add their own projects. Tim

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[Twisted-Python] Need help implementing Twisted
by C Ratchet May 13, 2005

May 13, 2005

Hello, I'm looking for some developers who can help implement Twisted functionality for my Snowball Fight game at http://snowballz.literati.org We're probably going to use Tofu, which is the Soya3D network layer based on Twisted. http://oomadness.tuxfamily.org/en/tofu/index.html If anyone's interested in helping out just reply to this mail. Thanks Ratchet

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[Twisted-Python] Evangelism notes...
by Mike C. Fletcher May 12, 2005

May 12, 2005

As some of you know, I use Twisted to develop one of our products, a fairly large Cable modem management application. I've developed and released TwistedSNMP, and am, generally speaking comfortable with the package. I've also been using Twisted within the company for my other projects. I've just come back from a meeting where a decision was made to completely rewrite a *delivered* application on our own dime for the sole purpose of eliminating Twisted. I found this rather disappointing. I … [View More]realise that the problem lay in part in my own "choice" (didn't actually choose, it just happened) of projects with which to introduce Twisted, but I felt it would be useful to share the experience with others. The Project: * Cross-protocol server intended to act as a "web services" intermediary for payment-processing services from a number of different banking systems. o Fairly straightforward networking protocols on all sides o All protocols were custom (i.e. we had to write them) save the client-side interface (which was XMLRPC) o Seems like a perfect problem domain for Twisted * Initially coded using Twisted by me, then pair programming with a colleague as he took over lead on the project o If my goal had initially been to evangelise, I should have *started* the project with pair programming so that the system wasn't already in-place and mystifyingly complex + Even the Finger sample is mystifyingly complex if you jump into it at the end of the process + Unfortunately, I didn't realise the project would be passed on to someone else before completion, I'd thought it would remain part of my portfolio within the company + Even if we did start out together, we really should have done some *formal* training on Twisted, rather than relying on knowledge transfer via pair programming. Again, it started out just being a few lines here and there, we didn't see much being done beyond the base system. o He never, in the entire process, saw anything really come from Twisted (other than problems where the complexity of the system got in the way of doing the rather simple task (from his point of view)), since the low-level coding was already done when he started working with the system. + Probably would have been better to start him on the much larger project, where Twisted represents far less of the overall complexity of the application. o In particular, test-driven development with threading in the background for blocking operations caused significant headaches * Project was delivered, paid for, and has been running in production for a few weeks, but 2 reported bugs cropped up o To fix one, needed to update to 2.0 (deferred object cleanup)... this caused rather a lot of upset, as the sysadmins were upset about such a huge package needing to be updated (and they tried to do just the core packages first, which doubled the work-load involved in preparing that update versus using Sumo) o Fixing the other was no big deal, except that something in 2.0 changed how the test-suite was running so that it now hung on completion... * Now, at this point there had been serious conversations just an hour earlier during a management meeting about replacing Twisted for 2 separate projects. The entire company is watching as we go to fix the *trivial* error while we're together after the meeting... but the test suite won't complete. Must be something wrong with the background thread not exiting thinks I. o What do we call to shutdown the threadpool? I don't remember, let's check the reference docs... 20 minutes of searching for the 2.0 reference docs (with the entire company watching this)... finally ask on IRC... told to build them myself and contribute them. Cute, but didn't really drive home the whole "robust, professional, well-documented platform on which to develop business systems" meme as much as I'd hoped. (Some of that is definitely my fault, I was pretty frustrated by the time I went to IRC to ask where the documentation was). o Finally go with the 1.3 docs, hoping there's not some change to the API that's causing the problem (though that looks very probable at this point, the change to 2.0 being the primary difference between working and not). * Finally get the 1.3 docs, hack together a reactor.threadpool.stop() call with a dummy last-run-test-suite and get the test suite to run-and-exit... o Keep in mind, we've just had to introduce a glaringly ugly and fragile hack to get around something trivial. There may be a better way to run the tests, but it's a bit late for thinking of that now... * Now that we can run the test suite and focus on what happens during it, we discover that the ESMTP client can't connect to a local SMTP host without authentication (or at least, it wouldn't with the code we were using across the network to a remote host)... no documentation on the ESMTP client, of course.[1] * At which point my colleague (lead on this project) got well and truly fed up and decided to dump Twisted and rewrite the project in plain-old-Python. There's lots of points where, had I anticipated the problems, I might have salvaged the project in its current state. If I'd anticipated that the problems would be non-trivial to fix, I could simply have returned to my workstation and fixed them in a relaxed and pressure-free environment. I could have spelunked through the code to figure out the interfaces in lieu of documentation. That's fine for me, I already understand Twisted enough to spelunk through and find what I want, but it doesn't make a great argument when someone's simply mystified by all the pieces scattered here and there that seem to be joined by nothing more than hope and bailing wire. I could have done better at evangelising. In the end, though, I had to concede that stripping out Twisted and writing the code himself would probably be faster and easier in the long run than trying to work around problems in an under-documented "foreign" system (again, from his viewpoint). Especially given the small size of the project, a few simple select loops and a thread can solve 90% of what Twisted is providing for him. Thinking back on that conversation; at that point the *only* failing feature was the ESMTP-sending, and I'm pretty sure it would have resolved to something like passing a None instead of a "" for the username and password; but when it came right down to it, he's the one maintaining the code, and as far as he can see, Twisted just gets in the way. Don't know if the other project will be rewritten as well. Given decision on this one, I'd imagine it will. I'd also predict that Twisted is now Techne non Grata wrt any new development where it's not an explicit requirement (given that we're going to be eating costs on rewriting a project to eliminate it). Certainly I'll have a hard sell going forward. So, anyway, just felt the need to share that. Sorry again for the sharp post to IRC. Peace, all, Mike [1] How did ESMTP get in there anyway, if it's a 1.3 codebase? Well, it shares common functionality with the big application, one piece of that being the automated use of ESMTP. -- ________________________________________________ Mike C. Fletcher Designer, VR Plumber, Coder http://www.vrplumber.com http://blog.vrplumber.com [View Less]

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[Twisted-Python] how to cancel a long running job on a server ?
by Thomas Jung May 11, 2005

May 11, 2005

Hello, another newbie question: I have a server, where I can remotely call a function like remote_calc(), using the perspective broker, which returns giving a result. Sometimes, I want to cancel that computation, calling e.g. remote_cancel() (which remains to be implemented.....) How can I have remote_calc() not to return before the result is done, and still be able to call remote_cancel while its running ? I tried this: ============================================================= from … [View More]

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[Twisted-Python] Re: [Twisted-commits] r13763 - fix broken link to divmod.org.
by Mary Gardiner May 10, 2005

May 10, 2005

On Tue, May 10, 2005, Stephen Thorne wrote: > Author: stephen > Date: Tue May 10 18:57:26 2005 > New Revision: 13763 > > Modified: > trunk/doc/web/howto/woven.xhtml > Log: > fix broken link to divmod.org. I'll get to this eventually if you don't, but that actually needs to be fixed in about six documents. (I feel better about our need to set up redirects on tm.comn now that I know that divmod.org hasn't done it either.) -Mary

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[Twisted-Python] Blocking on deferreds during unit tests (e.g. deferredResult)
by Eric Mangold May 10, 2005

May 10, 2005

I'm starting a new thread on this because It's very important to me, and we need to have some kind of resolution on this issue. On Fri, 06 May 2005 16:00:50 +1000, Jp Calderone <exarkun(a)divmod.com> wrote: [...] > Do > > _____not_____ > > use > > deferredResult > > (or deferredError or wait) > > As someone who pushed for their existence, I apologize. > > Jp I would like to have more details on this considering … [View More]

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