Mailman 3 December 2001 - Twisted

[Twisted-Python] python's "import" is giving me a headache.
by Glyph Lefkowitz 05 Dec '01

05 Dec '01

So, there's a particular corner of the coding standard for Twisted currently which is the root of a few annoying problems and has been the cause of one or two bugs. It's the module import requirement. Originally it seemed like a pretty good idea for the following reasons; if one is using packages, it is easiest to figure out where the code is coming from if you name the module explicitly. Documentation generators document modules individually, and so that's how people would learn to import modules. Accessing the module indirectly, and not the class, allows for reloading to work naturally and different modules to have similarly named classes when appropriate. In pracitce, it doesn't work out quite so well. It did not occur to me at the time how hard it would be to distinctly name all modules within classes, or how often a local variable name would clash with a straightforwardly chosen package name. I am considering a change to the coding standard (and the attendant massive refactoring) to a standard where modules "promote" public classes and functions to the module level. For example, in twisted/words/service.py: # promote public interface from twisted import python import twisted.words twisted.python.publicInterface(twisted.words, Service, WordsClientInterface, Participant, ...) # end The end user would probably then have to do this in order to use that module: import twisted.words.service from twisted import words words.Service(...) Pros: * fewer names to worry about clashing with * nested modules less inconvenient * only public portions of interface present at package level Cons: * it doesn't work that way now and it would require work to change * you still have to know which module to import * it requires manual declaration of public interface The number of conflicts both between modules and convenient variable names is increasing with time, and I think that something has to be done about it, but I don't know if this is an appropriate solution. At any rate, such a change will likely affect most Twisted developers, so I'd like to hear feedback before I do anything. -- ______ you are in a maze of twisted little applications, all | |_\ remarkably consistent. | | -- glyph lefkowitz, glyph @ twisted matrix . com |_____| http://www.twistedmatrix.com/

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[Twisted-Python] P2P Thoughts
by Jason L. Asbahr 05 Dec '01

05 Dec '01

Some folks on the decentralized list have praised a p2p app called 'Magi', which sounds like it has features similar to those in Twisted, or to those features which Twisted might soon acquire. Magi Express and uServ apparently have some overlap. Check out the Magi link and read the brochure. There is a screen shot there that looks roughly as complex as the Watson interface. Not so hard to put together. "Installing Magi Express turns your PC into a personal web server, providing the ability to share, store, retrieve and edit-in-place documents and other files to and from any other Magi-installed device. Magi Express is perfect for setting up your own personal intranet, shared workspace, or virtual private network. You will have the ability to e-mail, fax or print any file within your private network. You even have the ability to do so using a WAP-enabled phone when away from your Internet-connected PC." http://www.endeavors.com/express.html I suggested to Glyph that Twisted could someday replace Jigsaw as W3C's collaboration server. Now I'm thinking that Twisted could be the GNU collaboration server, as Mailman is the GNU mailing list manager. Or at least achieve that level of ubiquity in the open source world. :-) ______________________________________________________________________ Jason Asbahr jason(a)asbahr.com

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[Twisted-Python] 0.12.3 is out
by Chris Armstrong 05 Dec '01

05 Dec '01

You heard it here first, folks. Grab Twisted 0.12.3 at http://twistedmatrix.com/downloads/ - here are the changes: This is mainly a maintenance release; there are a bunch of bugfixes, but some really cool new things. A Configuration System. This is going to be the Next Big Thing in Twisted - right now, it's not used anywhere visibly, but the idea is a unified interface for Twisted that will replace things like 'mktap'. We have a basic dependancy system down, and a simple Web UI. A few bugfixes for TK InstanceMessenger. Docs for Delayeds: Itamar wrote up a small HTML document on how to use Delayeds. Look in the 'doc/' subdirectory. Other general bugfixes. -- QOTR: <Intention> Twisted did raise me from the dead after two weeks. It is a miracle of software engineering. -- Chris Armstrong <<< radix(a)twistedmatrix.com >>> http://twistedmatrix.com/users/carmstro.twistd/

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[Twisted-Python] Standalone IRC server, or Passport/Words/Something sucks
by Itamar Shtull-Trauring 04 Dec '01

04 Dec '01

Attached is an IRC server that acts more or less like a regular IRC server - anyone can login with no prior account. Issues: 1. It takes 3 seconds until connectionLost is called, so you can't immediately relogin. 2. The automatic user creation is horribly verbose, hard to understand, and hacky (getPerspectiveNamed, specifically.) 3. You get contacted by "*login*" every time you login. 4. You still need a password, though in this setup it knows its own password so the user doesn't deal with (and for my use this is good since I need a password protected IRC server.) =============================================== from twisted.protocols import protocol from twisted.words import service, ircservice from twisted.internet import passport class SimpleService(service.Service): """A simple IRC service that creates users on the fly.""" def removePerspective(self, name): if self.participants.has_key(name): del self.participants[name] self.application.authorizer.removeIdentity(name) def createParticipant(self, name): if not self.participants.has_key(name): log.msg("Created New Participant: %s" % name) def getPerspectiveNamed(self, name): if self.participants.has_key(name): raise service.WordsError, "user exists" else: p = service.Participant(name) p.setService(self) ident = passport.Identity(name, self.application) ident.setPassword("ugly hack") self.application.authorizer.addIdentity(ident) p.setIdentity(ident) ident.addKeyForPerspective(p) self.participants[name] = p return p class IRCChatter(ircservice.IRCChatter): passwd = "ugly hack" # remove this to force user to send password def connectionLost(self): ircservice.IRCChatter.connectionLost(self) print self.nickname self.service.removePerspective(self.nickname) class IRCGateway(protocol.Factory): def __init__(self, service): self.service = service def buildProtocol(self, connection): """Build an IRC protocol to talk to my chat service. """ i = IRCChatter() i.service = self.service return i def main(): """Run an IRC server""" from twisted.internet import main app = main.Application("irc") svc = SimpleService("twisted.words", app) irc = IRCGateway(svc) app.listenTCP(6667, irc) app.run(0) if __name__ == '__main__': main()

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[Twisted-Python] Collaboration Server: IBM's uServ
by Jason L. Asbahr 03 Dec '01

03 Dec '01

>From the decentralized list, research that looks useful for Twisted-to- Twisted (t2t) data publishing. :-) "uServ is a project at IBM which exploits P2P techniques to provide a reasonable alternative to paid web hosting services for a wide class of users. While you can't (yet) use it unless you have IBM intranet access, we've made a research report available describing our internal deployment and the technical details of the system." http://www.almaden.ibm.com/cs/people/bayardo/userv/ ______________________________________________________________________ Jason Asbahr jason(a)asbahr.com

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[Twisted-Python] FAQ-o-matic
by Michael Dartt 03 Dec '01

03 Dec '01

I'd like to suggest the addition of a FAQ-o-matic (http://faqomatic.sourceforge.net/fom-serve/cache/427.html)to the Twisted site. I think it would make it much easier to get and to post info, as you wouldn't have to wait for someone to write The Definitive Documentation(tm) for a given subject. From what I've seen/experienced, the "document-as-you-go" approach works much better for open-source projects. I'm willing to do the work of getting the F-o-m set up. (Perhaps I should stick in in my personal space?)

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[Twisted-Python] WebWidgets and Struts
by Jason L. Asbahr 02 Dec '01

02 Dec '01

As an example for WebWidgets, has anyone looked at the Struts framework of the Jakarta project? The general idea is that Struts tries to capture the common patterns of web application development and to provide a framework for rapid development using a common codebase. Apparently a number of folks are developing projects using this framework and a certain amount of code sharing is emerging. Reading through the website, it looks a lot like WebWare... >From the Struts page: "The goal of this project is to provide an open source framework useful in building web applications with Java Servlet and JavaServer Pages (JSP) technology. Struts encourages application architectures based on the Model-View-Controller (MVC) design paradigm, colloquially known as Model 2 in discussions on various servlet and JSP related mailing lists. Struts includes the following primary areas of functionality: - A controller servlet that dispatches requests to appropriate Action classes provided by the application developer. - JSP custom tag libraries, and associated support in the controller servlet, that assists developers in creating interactive form-based applications. - Utility classes to support XML parsing, automatic population of JavaBeans properties based on the Java reflection APIs, and internationalization of prompts and messages." Main page: http://jakarta.apache.org/struts/index.html Introduction: (Read this one) http://jakarta.apache.org/struts/userGuide/introduction.html Jason ______________________________________________________________________ Jason Asbahr jason(a)asbahr.com

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