Mailman 3 March 2007 - Twisted

[Twisted-Python] TCP client that can connect to a server at periodic intervals
by Gaspard, Bradley S 15 Mar '07

15 Mar '07

I am trying to write a TCP client that at regular intervals connects to a server makes a request and then closes the connection. Below is the code I've been playing with. I've seen an example of LoopingCall used for periodically sending UPD packets but am not sure how it would apply here because it would seem I need to periodically create new Protocol instances in the ClientFactory class. I've looked for examples and through the documentation but have come up empty. Any pointers would be greatly appreceiated. class AnnouncementFetcher(protocol.Protocol): def connectionMade(self): print "connectionMade called" self.transport.write(MSG_INFO_IPC) def dataReceived(self, data): print "Received: ", repr(data) # self.factory.share.saveData(data) self.transport.loseConnection() class AnnouncementFetcherFactory(protocol.ClientFactory): protocol = AnnouncementFetcher def __init__(self, share): self.share = share def buildProtocol(self, addr): print 'Connected.' p = AnnouncementFetcher() p.factory = self return p def clientConnectionLost(self, connector, reason): print 'Lost connection, Reason:', reason reactor.callLater(5, self.buildProtocol, 'localhost') def clientConnectionFailed(self, connector, reason): print 'Connection failed. Reason:', reason

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[Twisted-Python] web.resource.Resource.putChild() problem
by John Pote 15 Mar '07

15 Mar '07

Hi, can someone help. I've used the code snippet below to create a http control site for a web app. But I want to re-render the html pages from a sub dir, 'controlSit/pp', so I figured putChild() would help. def makeControlSite(): site = static.File('controlSite') site.putChild('pp', ProcessPage()) return site So I set the app going with twistd and the site files, control/*.* and control/pp/*.* get returned to the browser as is. My ProcessPage() resource seems to be ignored. Does static.File look for child resources or can I not mix static.File with putChild() as I've attempted to do? Help appreciated, John

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[Twisted-Python] CPU choice for big twisted server.
by Alec Matusis 15 Mar '07

15 Mar '07

Hello I am running a poll reactor with Twisted 2.2 on 2.6.11 kernel. "top" currently shows 80-90% CPU utilization for this twistd process. We have not switched to epoll Twisted 2.5 yet, although we are planning to. We are going to add boxes to run these servers. We have a choice of getting either Opteron 2216 with 1MB L2 cache and faster RAM access, or Intel Woodcrest 5140 with 4MB L2 and slower FB-DIMM RAM access. The current RSS size of the twisted process is about 60MB. The main load comes from poll() and from modifying long dictionaries of the protocol class instances (searching/modifying dictionaries of client sessions). Where should we expect a better performance: on Woodcrest 5140 with bigger L2 or on Opteron 2216 with faster RAM access? We need to order the new box tomorrow afternoon, so if someone could reply today, it'd be great for us! Thanks Alec.

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[Twisted-Python] Using Twisted for a SOAP/SIP gateway
by Pedro Sanchez 15 Mar '07

15 Mar '07

(resent: Previous message went under a different thread) Hello, I will likely get to work on a gateway between SOAP-based Web Services and SIP-based services. I would like to explore the possibility of implementing it using the Twisted framework and I'd appreciate if you can give me suggestions on: 1. Which SOAP stack to use. I've heard that ZopeLib is the way to go these days. 2. Which SIP stack to use. I will eventually fire questions about the overall architecture the gateway software should have. Any hints here are welcome. Thank you, -- Pedro

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[Twisted-Python] What is the most recent compatible combination of Twisted and Twisted.web2?
by Jonathan Mark 15 Mar '07

15 Mar '07

My Redhat 7.3/Python 2.5 box had TwistedWeb2-0.2.0 and Twisted 2.5 . However, they are not compatible. What is the most recent combination of Twisted and Twisted.Web2 that I could use together? Where can I get the most recent version of Twisted.Web2? TwistedMatrix doesn't seem to have a link to it. ____________________________________________________________________________________ Never miss an email again! Yahoo! Toolbar alerts you the instant new Mail arrives. http://tools.search.yahoo.com/toolbar/features/mail/

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[Twisted-Python] Producers / Consumers and more examples tutorials?
by jarrod roberson 13 Mar '07

13 Mar '07

Are there any more concrete examples or tutorials of using Producers and Consumers?

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[Twisted-Python] Streaming in AMP
by Jamu Kakar 12 Mar '07

12 Mar '07

Hi, Glyph has been kind enough to share some of his ideas about adding streaming support to AMP via private mail. He suggested that the discussion should really be on the list. Here's the relevant technical details we've discussed so far: (I made the comments in quotes; Glyph's response follows) >When you get a chance to get to the AMP streaming spec please let me >know. I'm interested in learning more about AMP and possibly helping >out with it. Since there is basically about a 5% probability that I will actually manage to write something that looks like a spec, let me take this random email response as an opportunity to get started. The protocol limitation in AMP of 64k per value is intentional, and in fact, should regarded as a very high end for a per-packet payload. The idea of AMP is that the connection should be a multiplexable resource which can do lots of things at the same time; if you start plugging it up with megabyte-at-a-time payloads, then when you send a packet over it, it's not going to get there in a reasonable time frame. So the idea behind AMP streaming is that there should be a parameter type which presents an API that allows you to deal with a "large" value that might be a multi-gigabyte stream, chunked up into smaller fragments so that you can have one connection downloading multiple things. I haven't completely decided on the API yet, but just to give you an idea of where I'm going: class Put(amp.Command): arguments = [('upload', amp.Upload()), ('filename', amp.Unicode())] # ... def put(upload, filename): def saveResult(result): f = file(filename, 'wb') f.write(result) f.close() upload.fullResultAsString().addCallback(saveResult) return {} Put.responder(put) This is a straw-man API because the *suggested* API for doing something like this would be to incrementally write the results to a file as they're available, but a hacky convenience API like this might be useful in some applications (and as an example it's less code to write). Another, possibly better convenience API might be 'fullResultAsTemporaryFile'. The implementation technique here would be to make the AMP protocol object a multiplexable consumer, and establish a convention (perhaps some built-in commands?) for sending chunks of a previously-identified file object. You can find the notifications involved in this process documented here: http://twistedmatrix.com/projects/core/documentation/howto/producers.html Is this helpful as the beginnings of a specification? Let me know if you need more information.

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[Twisted-Python] Vote: The Engine of Your Internet
by Duncan McGreggor 12 Mar '07

12 Mar '07

Vote now! In the spirit of all contests that are thinly disguised high school popularity contests, there is a poll up on jyte.com, and we need your help! http://jyte.com/cl/twistedmatrix.com-is-the-engine-of-your-internet Because, if we loose... well... the Jocks will get to claim the sandpit for their debauched parties, and where will we host our late-night chess and math club parties? d

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Re: [Twisted-Python] Running FTP server as a thread (as opposed to twistd -f ftp.tap)
by Andy Leszczynski 12 Mar '07

12 Mar '07

>You can't run just an FTP server in a thread, but you can run the whole >reactor in a thread. This is what I meant - I have a hybrid app so threads are only solution (for now). >The threaded approach looks something vaguely like this (untested): [...] thx a lot - work like a charm.

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[Twisted-Python] Running FTP server as a thread (as opposed to twistd -f ftp.tap)
by Andy Leszczynski 12 Mar '07

12 Mar '07

Hi, I need to launch the twisted based FTP server as a part of my application. I could spawn/control a separate process with subprocess/popen2/etc. However for other reasons I would rather prefer to have it as a separate thread of my app. The question is how to convert mktap generated file into a piece of python code. Thx, Andy

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