[Pythonmac-SIG] distributed objects with PyObjC

[Keith Ray]

I'm trying to test-implement Distributed Object using the example
server / client from the book "Cocoa Programming" by Scott Anguish,
Erik M. Buck, Donald A. Yacktman (chapter 23).
<http://www.cocoaprogramming.net/Downloads.html>

I've kept the sample server in Objective C, and I'm trying to
implement the client in PyFit.

What I'm stuck on right now is a crash calling

   self.server.addMessageClient_( self )

in my method  applicationDidFinishLaunching_

Do you have any suggestions?   I can send the crash-log as well...

Here's the python source code:
************************************

#
#  DOTestPythonClientAppDelegate.py
#  DOTestPythonClient
#

from Foundation import *
from AppKit import *

from PyObjCTools import *
from objc import *

MYMessageServerProtocol = formal_protocol( u'MYMessageServerProtocol', None, [
    selector( None, selector='addMessageClient:', signature='Vv12 at 0:4 at 8'),
    selector( None, selector='removeMessageClient:', signature='c12 at 0:4 at 8'),
    selector( None, selector='broadcastMessageString:',
signature='Vv12 at 0:4 at 8') ] )

class DOTestPythonClientAppDelegate(NibClassBuilder.AutoBaseClass):

    composeView = ivar(u'composeView')
    messageView = ivar(u'messageView')
    sendButton = ivar(u'sendButton')
    server = None

    def sendMessage_(self,aSender):
        NSLog( u"sendMessage_ ." )
        self.server.broadcastMessageString_( self.composeView.string() )
        self.composeView.setString_( u'' )

    def appendMessageString_(self,aSstring):   # called by server...
        NSLog( u"appendMessageString ." )
        #NSRange
        appendRange = NSMakeRange( self.messageView.string().length(), 0);
        #Append text and scroll if neccessary
        self.messageView.replaceCharactersInRange_withString_(
appendRange, aString );
        self.messageView.scrollRangeToVisible_( appendRange )
        return self

    def connectionDidDie_(self,aNotification):
        NSLog( u"Error: Connection to server is broken." )

    def applicationDidFinishLaunching_(self,aNotification):
        NSLog( u"applicationDidFinishLaunching_ ." )
        self.server =
NSConnection.rootProxyForConnectionWithRegisteredName_host_(
u"server", None ).retain()
        if None == self.server :
            NSLog( u"Error: Failed to connect to server." )
        else:
            NSLog( u"did connect to server." )
            connectionDidDie_SEL = selector( self.connectionDidDie_,
                selector='connectionDidDie:', signature="v12 at 0:4 at 8" )
            NSNotificationCenter.defaultCenter().addObserver_selector_name_object_(
                self, connectionDidDie_SEL,
NSConnectionDidDieNotification, None )
            NSLog( u"called
defaultCenter().addObserver_selector_name_object_." )

            self.server.setProtocolForProxy_( MYMessageServerProtocol )
            NSLog( u"called self.server.setProtocolForProxy_." )

            self.server.addMessageClient_( self )   # crashing here...
            NSLog( u"called self.server.addMessageClient_." )

            astr = u"Connected: %s %d" %
NSProcessInfo.processInfo().processName(),
NSProcessInfo.processInfo().processIdentifier()
            NSLog( u"astr = '%s'" % astr )

            self.server.broadcastMessageString_( astr ) # convert to NSString
            NSLog( u"called self.server.broadcastMessageString_." )

    def applicationWillTerminate_(self,aNotification):
        NSLog( u"applicationWillTerminate_ ." )
        if NO == self.server.removeMessageClient_(self) :
            NSLog( u"Error: Failed to remove client." )
        self.server.release()
        self.server = None



--

C. Keith Ray
<http://homepage.mac.com/keithray/blog/index.html>
<http://homepage.mac.com/keithray/xpminifaq.html>
<http://homepage.mac.com/keithray/resume2.html>