How to get input from SocketServer MyTCPHandler to another class

Question

I am trying to get an input from MyTCPHandler into the class Network in the following program. So Ideally I would like, for example, to take the self.data from MyTCPHandler and change the self._title in Network. As usual, I apologize for the simple question, but I am very new to classes in python and I am struggling a bit with this one. Thanks for your help!

from Tkinter import *
import time
import math
import lockfile
import functions
import SocketServer
import threading

class Network(Frame):  
    """ Implements a stop watch frame widget. """                                                               
    def __init__(self, parent=None, **kw):      
        Frame.__init__(self, parent, kw)

        HOST, PORT = "192.168.2.3", 9999
        self._server = SocketServer.TCPServer((HOST, PORT),MyTCPHandler)
        t = threading.Thread(target=self._server.serve_forever)
        t.setDaemon(True) 
        t.start()

        self._title="hello"
        self.makeWidgets()    

    def makeWidgets(self):                       
        """ Make the time label. """

        self._canvas = Canvas(self, width=600, height=400)
        self._canvas.pack()



class MyTCPHandler(SocketServer.BaseRequestHandler):
    """
    The RequestHandler class for our server.

    It is instantiated once per connection to the server, and must
    override the handle() method to implement communication to the
    client.
    """

    def handle(self):
        self.data = self.request.recv(1024).strip()
        print "{} wrote:".format(self.client_address[0])
        print self.data
        #I want to set the above title to "self.data"        
        self.request.sendall(self.data.upper())




def main():
    root = Tk()

    #sw = StatusTable(root)
    #sw.pack(side=RIGHT)

    nw = Network(root)
    nw.pack(side=TOP)


    root.mainloop()


if __name__ == '__main__':
    main()

I am still struggling with this, my current code is below. I have two questions.
1. Ideally I would like to set the IP address insider the Network class, is this possible? 2. It appears that self._server does not have an attribute "_title", which is the one I am trying to pass from MyTCPHandler.

from Tkinter import *
import time
import math
import lockfile
import functions
import SocketServer
import threading


class Network(Tk):  
    def __init__(self,server):      
        Tk.__init__(self)

        self._server=server
        t = threading.Thread(target=self._server.serve_forever)
        t.setDaemon(True) # don't hang on exit
        t.start()

        self.makeWidgets()    

    def makeWidgets(self):                       
        """ Make the time label. """

        self._canvas = Canvas(self, width=600, height=400)
        self._canvas.pack()

        radius=20
        l = Label(self,text=self._server._title)
        l.pack(fill=X, expand=NO, pady=2, padx=2)   

class MyTCPHandler(SocketServer.BaseRequestHandler):
    def __init__(self):     
        self._title=StringVar()
        self._title="test"

    def handle(self):
        # self.request is the TCP socket connected to the client
        self.data = self.request.recv(1024).strip()
        print "{} wrote:".format(self.client_address[0])
        print self.data
        self._title="change"
        print "changed?"
        # just send back the same data, but upper-cased
        self.request.sendall(self.data.upper())



def main():

    HOST, PORT = "10.0.1.08", 9999
    print HOST

    # Create the server, binding to localhost on port 9999
    server = SocketServer.TCPServer((HOST, PORT),MyTCPHandler)

    #sw = StatusTable(root)
    #sw.pack(side=RIGHT)

    nw = Network(server)
    nw.mainloop()

Answer 1

Since both classes are in the same process (and hence same memory space), why not just use a shared data. If you are worried about data being overwritten by threads, then you can add a lock on that data.

You could also consider making the second class an instance of the first one -- in that case, sharing data would be seamless. Here is a discussion, you might find useful: How to share data between two classes

Try this (you can remove the lock, if you have only one client and it is okay to be overwritten):

lock = threading.Lock()
data_title = ""

class Network(Tk):
    def __init__(self,server):
        Tk.__init__(self)

        self._server=server
        t = threading.Thread(target=self._server.serve_forever)
        t.setDaemon(True) # don't hang on exit
        t.start()

        self.makeWidgets()

    def makeWidgets(self):
        """ Make the time label. """
        print(dir(self._server))

        self._canvas = Canvas(self, width=600, height=400)
        self._canvas.pack()

        radius=20
        lock.acquire()
        l = Label(self,text=data_title)
        lock.release()
        l.pack(fill=X, expand=NO, pady=2, padx=2)

class MyTCPHandler(SocketServer.BaseRequestHandler):
    def __init__(self):
        self._title=StringVar()
        self._title="test"

    def handle(self):
        # self.request is the TCP socket connected to the client
        self.data = self.request.recv(1024).strip()
        print "{} wrote:".format(self.client_address[0])
        print self.data
        lock.acquire()
        self._title="change"
        lock.release()
        print "changed?"
        # just send back the same data, but upper-cased
        self.request.sendall(self.data.upper())