Mailman 3 September 2011 - Twisted-web

Test
by Philippe Lafoucrière 05 Aug '21

05 Aug '21

Hi all just a test

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Porting the features of nevow.guard to twisted.web.guard
by L. Daniel Burr 04 Jan '12

04 Jan '12

Hi gang, Per a short chat with exarkun (thanks exarkun), I'm posting this to the list for discussion. A project upon which I am working requires a twisted.web service that allows a user to delegate authentication/authorization to a third party, e.g., Facebook, Twitter, et cetera. In so doing, I've found myself missing nevow.guard, since web.guard currently only has out-of-the-box support for HTTP Auth. I'd like to see web.guard expand to cover more kinds of auth, such as form-based auth or the OAuth-based solutions coming from so many social graph sites. With this in mind, I asked exarkun about this, and he mentioned that the only thing he does not consider to be garbage in nevow.guard is the feature-set, and that I should port the features to web, discarding the baggage. I'd like to solicit the list for some guidance as to what those features are, or should be, and hopefully end up with a ticket describing the features to be implemented, which I will then attempt to implement and contribute to twisted.web. Thanks, Daniel -- L. Daniel Burr ldanielburr(a)mac.com (312) 656-8387

5 5

CorePost 0.0.7 - all about content types
by Jacek Furmankiewicz 02 Oct '11

02 Oct '11

CorePost 0.0.7, the REST microframework built on top of twisted.web is out. http://pypi.python.org/pypi/CorePost/0.0.7 This is a big release with lots of enhancements all around content types: 1) automatic parsing of incoming content based on type @route("/post/json",(Http.POST,Http.PUT)) def test_json(self,request,**kwargs): return "%s" % json.dumps(request.json) @route("/post/xml",(Http.POST,Http.PUT)) def test_xml(self,request,**kwargs): return "%s" % ElementTree.tostring(request.xml) @route("/post/yaml",(Http.POST,Http.PUT)) def test_yaml(self,request,**kwargs): return "%s" % yaml.dump(request.yaml) 2) ability to route to different methods for the same URL by incoming content @route("/post/by/content",(Http.POST,Http.PUT),MediaType.APPLICATION_JSON) def test_content_app_json(self,request,**kwargs): return request.received_headers[HttpHeader.CONTENT_TYPE] @route("/post/by/content",(Http.POST,Http.PUT),(MediaType.TEXT_XML,MediaType.APPLICATION_XML)) def test_content_xml(self,request,**kwargs): return request.received_headers[HttpHeader.CONTENT_TYPE] @route("/post/by/content",(Http.POST,Http.PUT),MediaType.TEXT_YAML) def test_content_yaml(self,request,**kwargs): return request.received_headers[HttpHeader.CONTENT_TYPE] @route("/post/by/content",(Http.POST,Http.PUT)) def test_content_catch_all(self,request,**kwargs): return MediaType.WILDCARD 3) ability to return dict/list response and have them automatically convert to JSON or YAML, depending on what caller can Accept @route("/return/by/accept") def test_return_content_by_accepts(self,request,**kwargs): val = [{"test1":"Test1"},{"test2":"Test2"}] return val Calling this URL with "Accept: application/json" will return: [{"test1": "Test1"}, {"test2": "Test2"}] Calling it with "Accept: text/yaml" will return: - {test1: Test1} - {test2: Test2} 4) proper support for *defer.returnValue()* *in @defer.inlineCallbacks routers (which supports the auto-conversion shown above) @route("/",Http.GET) @defer.inlineCallbacks def root(self,request,**kwargs): val1 = yield db.query("SELECT ....") val2 = yield db.query("SELECT ....") defer.returnValue(val1 + val2) Cheers, Jacek

5 19

sending "100 Continue" from my twisted.web2 server
by Gustavo Garcia Bernardo 22 Sep '11

22 Sep '11

Hi, What is the proper way to implement sending a provisional response (100 Continue) before sending the final response (200) with the content? Thank you, G. Este mensaje se dirige exclusivamente a su destinatario. Puede consultar nuestra política de envío y recepción de correo electrónico en el enlace situado más abajo. This message is intended exclusively for its addressee. We only send and receive email on the basis of the terms set out at. http://www.tid.es/ES/PAGINAS/disclaimer.aspx

1 0

Twisted Conch SSL session Key from Request
by Caleb P. Burns 22 Sep '11

22 Sep '11

Is it possible to retrieve the SSL session or master key from a `twisted.web.http.Request` instance? I want to use it along with other data to generate a hash-keyed message authentication code (HMAC).

3 3

Role-based security authorization
by Jacek Furmankiewicz 06 Sep '11

06 Sep '11

While reading up the docs on Twisted security and HTTP auth, it seems they are all geared towards pure authentication, but don't address the authorization part. For example, in our other apps we often have a security setup like this a) users with READ_ONLY_ROLE can only access GET endpoints b) users with READ_WRITE_ROLE can access GET, POST, PUT, DELETE endpoints Is there any existing Twisted-based projects that provides a role-based authorization framework on top of the core Twisted authentication APIs? It would need a custom Avator with roles attached to it (fetched from DB or elsewhere) Thanks Jacek

1 0

CorePost - a tiny Flask-style REST microframework for twisted.web
by Jacek Furmankiewicz 06 Sep '11

06 Sep '11

Hi, I'd like to announce the very first alpha release of CorePost, a tiny REST microframework on top of the core twisted.web APIs. http://pypi.python.org/pypi/CorePost/0.0.1 it's design is heavily inspired by Flask, for easy creation of REST services. Looking forward to any comments and suggestions. It's my first attempt at any serious Twisted programming, so be gentle with your comments :-) Cheers, Jacek P.S. I plan to look at integrating twisted.internet.processes http://pypi.python.org/pypi/twisted.internet.processes in the near future to enable scaling to all cores on a multi core machine. using its deferToProcess() functionality. Any suggestions from seasoned Twisted developers on whether that is the correct approach would be appreciated.

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Coding websockets server.
by João Ricardo Mattos e Silva 06 Sep '11

06 Sep '11

Hey, my first e-mail on this list, I`m beginning to code with twisted, started after a research about building c10k servers.. (with python) I am using this lib, heard it is the best for working with websockets (correct me if you know another) https://github.com/wulczer/txWebSocket Well, There is what I want to do: I have: site = WebSocketSite(root) site.addChatHandler('/room*1*', Chathandler) reactor.listenTCP(8080, site) where class Chathandler(WebSocketHandler): users = set() def __init__(self, transport): WebSocketHandler.__init__(self, transport) def __del__(self): print 'Deleting handler' def setUsers(self,usr): self.users = usr def frameReceived(self, frame): adr = self.transport.getPeer() print "Msg rcv from: ", adr self.sendChat(adr,frame) def connectionMade(self): print 'Connected to client.' self.users.add(self) def connectionLost(self, reason): print 'Lost connection.' if self in self.users: self.users.remove(self) def sendChat(self,fr,msg): for u in self.users: u.transport.write(str(fr)+msg) My problem is: If I do this: site = WebSocketSite(root) site.addChatHandler('/room*1*', Chathandler) site.addChatHandler('/room*2*', Chathandler) site.addChatHandler('/room*3*', Chathandler) reactor.listenTCP(8080, site) will not work (every room will comunicate with every room), because the users = set() will be globally between the handlers.. If I put on the __init__, every call on /roomX will have your personal set() of users including only themselfs. I am kind stuck on this, I`m new to websocket and server programming, so I don`t even know if is the best way to code a chatroom server. If you read this far ans have any (even it looks that stupid for you), might help right now (: Thanks, -- *João Ricardo Mattos e Silva* Graduando em Ciência da Computação na Universidade Federal de Santa Catarina *Cel: *+55 (48) 96190063 | *Skype:* jricardomsilva | * Msn: * joaoricardo(a)globalite.com.br

3 2

using @defer.inlineCallbacks and yield correctly
by Stephan 01 Sep '11

01 Sep '11

I'm sending this email to separate out the two issues I'm having to gain a better understanding of how to properly code what I'm attempting to do. I'd like to use spawnProcess to spawn a process but with a timeout. If the timeout is reached I'd like to kill the process. You can see in the error section that I'm getting an error with defer and no yield. I was hoping someone could tell me what my code is supposed to do that it's not doing so that I can stop getting the error found at the bottom. from what I understand @defer.inlineCallbacks is used to defer a async callback function like how i'm using CallLater below, but where is the yield supposed to be? and how should the below code change? ======================== Code ======================== command = "xvfb-run --auto-servernum firefox -P %s" % profile_id logging.debug("command: %s", command) args = shlex.split(command) self.pp = TimedProcessProtocol(self, 100) subprocess = reactor.spawnProcess(self.pp, args[0], args, env = os.environ, usePTY=1) logging.debug("spawned a process: pid: %d", subprocess.pid) self.pid = subprocess.pid ======================== ProcessProtocol Class ======================== class TimedProcessProtocol(protocol.ProcessProtocol): def __init__(self, firefoxProcess, timeout): self.timeout = timeout self.firefoxProcess = firefoxProcess self.killed = None def isProcessDead(self): logging.debug("isProcessDead called") if self.killed is None: return False else: logging.debug("process is dead!!__________") return True def killProcessIfAlive(self): logging.debug("killProcessIfAlive called") #(a)defer.inlineCallbacks try: #yield self.transport.signalProcess('KILL') if self.killed is None: os.kill(-self.transport.pid, signal.SIGTERM) except error.ProcessExitedAlready: logging.debug("process already exited") pass def connectionMade(self): logging.debug("connection made timeout = %d", self.timeout) @defer.inlineCallbacks def onTimer(): logging.debug("timeout triggered") self.firefoxProcess.handleProcessTimedOut() self.killProcessIfAlive() d = reactor.callLater(self.timeout, onTimer) ======================== Errors ======================== 2011-08-31 12:30:22-0700 [-] Unhandled error in Deferred: 2011-08-31 12:30:22-0700 [-] Unhandled Error Traceback (most recent call last): File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1170, in run self.mainLoop() File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1179, in mainLoop self.runUntilCurrent() File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 778, in runUntilCurrent call.func(*call.args, **call.kw) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 944, in unwindGenerator return _inlineCallbacks(None, f(*args, **kwargs), Deferred()) --- <exception caught here> --- File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 823, in _inlineCallbacks 3, in _inlineCallbacks result = g.send(result) exceptions.AttributeError: 'NoneType' object has no attribute 'send'

3 3

Re: [Twisted-web] stopping LoopCall and check if running
by Terry Jones 31 Aug '11

31 Aug '11

Hi Stephan I wont try to answer your question, but this error: > result = g.send(result) > exceptions.AttributeError: 'NoneType' object has no attribute 'send' is what you see when you decorate a function with @inlineCallbacks but don't have any yields in the function (i.e., it doesn't return a generator object). You should definitely find & fix that problem. Terry

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