Mailman 3 November 2004 - Twisted-web

[PATCH] Are we ready for a Page.remember fix?
by Alex Levy 23 Nov '04

23 Nov '04

This was suggested a long time ago, and when I tried adding it, I broke Quotient somewhat badly. From what I can tell, the problem in Quotient which prevented Page.remember from being changed has been fixed; I'd like to see this patch added. Some have suggested a SiteContext as an alternative; however, I see these two as addressing two different concerns. A SiteContext (as described in Roundup <http://divmod.org/users/roundup.twistd/nevow/issue137>) would be good for remembering data that are universal to a specific NevowSite instance. However, this is not my use case. In my case, I want my Realm to be able to remember objects that are particular to a certain logged in user. The obvious example is an ICurrentUser interface, which lets the resource hierarchy quickly reference what user (if any) is logged in. I'm sure I'll come up with other uses, but this is my current need. Doing this at the SiteContext level would (from what I can tell) produce overlaps when more than one user is logged in. So, are there any objections to Page.remember()? Even if it's not an elegant solution, it works for me, and it's generic enough that I think it's worth keeping. -- Alex Levy WWW: http://mesozoic.geecs.org/ "Never let your sense of morals prevent you from doing what is right." -- Salvor Hardin, Isaac Asimov's _Foundation_

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LineReceiver Protocol
by Michael Mata 22 Nov '04

22 Nov '04

Is there a way to extend the LineReceiver protocol to take action on a continued, periodic basis? Currently, the protocol only does work when a line is received. However, there are times when we the script to take action even without waiting to receive a line. For example, suppose a connection should be closed if it has been idle for more than X minutes. However, if connection is idle, it will not be sending commands. If no commands are sent, then no lines are received, which means there is no way to close the connection. Another example might be a global message that needs to be sent to all connections. The message would have to be stored in message queue and sent only when lineReceived is called. It would be nice if the message could instead be sent imediately even if the connection was currently idle.

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getting started with nevow
by Luc Saffre 22 Nov '04

22 Nov '04

Hello, I am experimenting with twisted and nevow. I have a twisted server running at http://lsaffre.dyndns.org:8088/ I am using the latest SVN snapshot of nevow. This server has some simple .rpy scripts; they all work, except the nevow scripts, who produce a traceback instead. You can see the traceback if you look at http://lsaffre.dyndns.org:8088/nevow2.rpy The source of this page is taken from http://www.divmod.org/Home/Projects/Nevow/index.html more exactly, here is the complete source: ------------- file nevow2.rpy : from formless.annotate import TypedInterface, Integer, String class ISimpleMethod(TypedInterface): def simple(self, name=String(description="Your name."), age=Integer(description="Your age.")): """Simple Please enter your name and age. """ class Implementation(object): __implements__ = ISimpleMethod, def simple(self, name, age): print "Hello, %s, you are %s years old." % (name, age) from nevow import rend, tags, loaders from formless import webform class WebForm(rend.Page): docFactory = loaders.stan( tags.html[ tags.body[ tags.h1["Here is the form:"], webform.renderForms('original') ] ]) resource = WebForm(Implementation()) --------------------- Question: what is going wrong here? tia, Luc

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Re[2]: [Twisted-web] Cobine Twisted with PHP
by webmaster＠haustierworld.de 19 Nov '04

19 Nov '04

Hi Alex I´ve already seen Twisted's web server. It isn´t exactly what I need :( I´m looking for something different like this: If a user logs in, PHP validates the values, loads infomation from database and posts theese information to my Twisted / Phython what ever script / server. Server keeps data in memory, does something with data and every 10 minutes, it writes updated data in database. So I´m only searching for a layer between PHP / Apache / MySQL. PHP has something like: http://de.php.net/manual/de/function.msg-receive.php is it possible to communicate over IPC with Twisted? Or is there a better way to do this? Thank you, Bastian

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Cobine Twisted with PHP
by webmaster＠haustierworld.de 19 Nov '04

19 Nov '04

Hi all :) I´m completly new to Twisted, I´ve installed it and think it is a good framework! Thanks for your work! Now I´m wondering if I could build a server with Twisted, wich offers information php could read. Is this possible? How has my server to look, if it offers e.g. the string "server"? And how could I connect to TwistedServer from PHP? It all should run on a LAMP system, so I don´t need the twisted webserver, do I? Pardon me, but I´m absolutly new to twisted, and I couldn´t find anything with PHP :( Thank you, Bastian

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nevow.wolf
by Peter Hunt 18 Nov '04

18 Nov '04

Hi everyone, I've been discussing this with a few people on #twisted.web, and after reviewing the code, I've decided it's time to show it off to a larger audience. I've committed a new package called wolf (flow backwards). It's available at http://www.divmod.org/svn/Nevow/sandbox/phunt/wolf/. Download that and drop it into your site-packages. Essentially, it lets you write web applications in a linear style instead of writing a bunch of ugly FSMs. For example, let's say you wanted to write a user registration system... from nevow import wolf # assume RegisterPage, ProfilePage, and SuccessPage are nevow Pages # RegisterPage asks for username and desired password # ProfilePage asks for name and age # SuccessPage is success regpage = wolf.callable_page(RegisterPage) # simplifies usage within wolf profpage = wolf.callable_page(ProfilePage) successpage = wolf.callable_page(SuccessPage) class Example(wolf.IndexedContainer): def _validate_reg(self, req): # TODO: make sure everything is ok with the form return True def _validate_prof(self, req): # todo return True def _regform(self, req): # underscore-prefixed methods cannot be called from outside while True yield regpage(req) if self._validate_reg(req): break def _profform(self, req): while True: yield profpage(req) if self._validate_prof(req): break def index(self, req): # this is the whole register routine yield self._regform(req) yield self._profform(req) yield successpage(req) You can connect this to a Nevow site by using: root.addChild("childname", wolf.WolfResource(Example)) Then, you can request it by going to: http://host/childname/ or http://host/childname/index Download the code, try it out. If you run Stackless, you get to use the back button, otherwise you're stuck with not being able to go back. There is an example.py file which is a fully working example of a guess-the-number game.

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_nevow_carryover_
by Aaron Bingham 17 Nov '04

17 Nov '04

Hi all, I have created some web forms. The input is handled by formless (although I just use annotate.Request() at the moment), and I am using request.setComponent(IRedirectAfterPost, "/some-path/") to redirect after submission. For some reason, the URL I get redirected to is like this: http://localhost:8080/some-path/?_nevow_carryover_=1100440412.88 Where is that extra query argument coming from, what is it good for, and how do I turn it off? I am using Nevow 0.3. Thanks, Aaron

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webform success message?
by Alexander May 17 Nov '04

17 Nov '04

When a form is submitted successfully using webform, is there a way to add a success message to the re-rendered form output?

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Xml-Rpc server troubles
by Andrea Nicolini 17 Nov '04

17 Nov '04

Hi All, I'm trying to debug a XML-RPC server I wrote because sometimes it gets stuck and I don't know why. I'm not a twisted expertise so I hope someone in this list can help me. I use the server to give access to a MySql database via XML-RPC, the client are written in python and java. The server runs fine for some days and then suddenly it hangs. When the server hangs I can connect to the server port but when I call a remote method the server doesn't respond. The server is not throwing any exception. I'm running the server on a RH9 using Python 2.2 and Twisted 1.3. Here's a snippet of code: def xmlrpc_createjob(self,hash): tscmfuncs.call_debug(debug,foreground) d = self.dbpool.runInteraction(self.createjob,hash) return d.addCallback(self.returnData) def createjob(self,cur,hash): """Method to create a new job -> returns the new job's id""" try: qparam = () cur.execute('SELECT * FROM jobtable') for field in cur.description: f = field[0] if hash.has_key(f): if type(hash[f]) == type(u''): qparam += (hash [f].encode('iso-8859-1'),) else: qparam += (hash[f],) else: qparam += (None,) cur.execute("INSERT INTO jobtable VALUES (%s,% s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,% s)",qparam) cur.execute("SELECT LAST_INSERT_ID() FROM jobtable") curid = cur.fetchone()[0] cur.close() except Exception,err: return 0 else: return curid I don't have any idea of what can cause this behaviour and how to debug the server. Any idea? Thank you. Bye. -- Andrea Nicolini mailto:andrea@teamsw.it im:aser76@jabber.linux.it http://www.teamsw.it Team Software S.r.l. Via Campagna 30 Cognento MO Tel 059.343790

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Nevow - 'connection lost' javascript alert on page reloads
by Sridhar R 16 Nov '04

16 Nov '04

I have even tried with the HEAD revision from subversion of Nevow, but the problem still persists! On page reloads (on loads), I get this javascript alert "The connection to the remote server was lost. The page may fail to work correctly. Reloading the page may fix the problem." Looking at liveevil.js if (xmlhttp.responseText) { connect(outputNum + 1) eval(xmlhttp.responseText) } else { alert('The connection to the remote server was lost. The page may fail to work correctly. Reloading the page may fix the problem.'); } xmlhttp.responseText is null !! It is supposed to be null only connection problems. So isn't this a bug? Here is the project that uses Nevow and gets the above problem http://svn.berlios.de/viewcvs/codehack/trunk/ Nevow code is kept under trunk/lib/codehack/server/ Service code is at trunk/lib/codehack/server/gateway.py .tac is here trunk/startserver.tac -- Sridhar R - http://cs.annauniv.edu/~rsridhar Blog: http://www.livejournal.com/~sridharinfinity

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