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<DIV><FONT face=Arial size=2>Hello,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am a Java Developer that has been learning Python
by doing simple things. I am loving this initial vibe I'm getting
out of Python. However, because I feel programmers of a
certain languages bring with them certain vices when moving to other
languages, I'd like to have feedback from seasoned Python programmers regarding
my code.</FONT></DIV>
<DIV><FONT face=Arial size=2>Using some socket examples I've googled here and
there I wrote a very simple Instant-Messaging-wannabe program.</FONT></DIV>
<DIV><FONT face=Arial size=2>Is there some sort of a Wiki where I could post the
code and have advice on what, how and where to improve? Or should I post the
code it here?</FONT></DIV>
<DIV><FONT face=Arial size=2>Actually, I'll post it below and if anyone knows of
a better place to do something like this I'll do it there.</FONT></DIV>
<DIV><FONT face=Arial size=2>Next I'm changing the client to include a server
thread listening instead of polling the server.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Regards</FONT></DIV>
<DIV><FONT face=Arial size=2>jorge</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>SIMPLE IM CLIENT</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>import socket, threading, time, msvcrt</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>print "Please enter the following
information"<BR>_url = raw_input("URL: ")<BR>_port = raw_input("Port:
")<BR>print "Starting IIM client on port: " + _port</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>socketOut = socket.socket(socket.AF_INET,
socket.SOCK_STREAM)<BR>socketOut.connect((_url, int(_port)))</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2># clear screen here</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>print "Enter your user details"<BR>_from =
raw_input("User id: ")<BR>_to = raw_input("Buddy id: ")</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>print '\n'<BR>print "Connecting to
server..."<BR>print '\n'</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2># send user details and receive
response<BR>socketOut.sendall(<A
href="mailto:'@@@'+_from+'##'+_to">'@@@'+_from+'##'+_to</A>)<BR>response =
socketOut.recv(8192)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>def listener():<BR> while
1:<BR>
time.sleep(5)<BR>
socketOut.sendall('$$$'+_from)<BR>
response = socketOut.recv(8192)<BR> if
response != "
":<BR> print
"\n" + response</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV><FONT face=Arial size=2>
<DIV><BR>if response == 'AUTH_OK':<BR> data =
""<BR> th =
threading.Thread(target=listener)<BR>
th.setDaemon(1)<BR> th.start()<BR> print
"Background polling thread started"<BR> while 1:</DIV>
<DIV> </DIV>
<DIV> if
msvcrt.kbhit():<BR>
ch = msvcrt.getche()<BR>
else:<BR> ch =
None<BR> if
ch:<BR> if ch
!=
'\r':<BR>
data += ch<BR>
else:<BR>
print
'\n'<BR>
socketOut.sendall('###'+_from+'##'+data)<BR>
response =
socketOut.recv(8192)<BR>
if response != "
":<BR>
print
response<BR>
data = ""</DIV>
<DIV> </DIV>
<DIV>else:<BR> print "Auhentication
failed!"<BR>
<BR>socketOut.close()</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>SIMPLE IM SERVER</DIV>
<DIV> </DIV>
<DIV>import SocketServer</DIV>
<DIV> </DIV>
<DIV>_port = 8881<BR>_clients = {}</DIV>
<DIV> </DIV>
<DIV># a connected client<BR>class Client:<BR> # queue of
messages sent to this client<BR> queue =
[]<BR> def __init__(self, _sock, _src,
_dest):<BR> print "Creating IM
client"<BR> self.socket =
_sock<BR> print "Incoming socket: %s"
% self.socket<BR> self.user =
_src<BR> print "Username: " +
self.user<BR> # buddies should be a
list<BR> self.buddy =
_dest<BR> print "Buddy: " +
self.buddy<BR> print "Created IM
client"</DIV>
<DIV> </DIV>
<DIV># the server handling requests<BR>class
Broker(SocketServer.BaseRequestHandler):<BR> def
handle(self):<BR> print "Connected
from", self.client_address<BR> while
True:<BR>
receivedData =
self.request.recv(8192)<BR>
if not
receivedData:<BR>
break<BR>
<BR> # if
handshake packet, extract client
details<BR> if
receivedData.startswith(<A
href="mailto:'@@@',0,3">'@@@',0,3</A>):<BR>
print "Received handshake
packet"<BR>
# strip handshake
code<BR>
receivedData = receivedData.replace(<A href="mailto:'@@@'">'@@@'</A>, '',
1).lstrip()<BR>
l =
receivedData.split('##',1)<BR>
socket =
self.request<BR>
src =
l[0]<BR>
dest =
l[1]<BR>
c = Client(socket, src,
dest)<BR>
# use username as key on
hashmap<BR>
_clients[src] =
c<BR>
# send success
message<BR>
socket.sendall('AUTH_OK')<BR>
print "Client " + src + " authenticated"</DIV>
<DIV> </DIV>
<DIV> # if
polling packet, extract sender details and send
messages<BR>
if
receivedData.startswith('$$$',0,3):<BR>
# strip polling
message<BR>
print "Received polling
packet"<BR>
src = receivedData.replace('$$$', '',
1).lstrip()<BR>
# only poll if more than 1
user<BR>
if len(_clients) >
1:
<BR>
# use username as key on
hashmap<BR>
_clients[src] =
c<BR>
if len(c.queue) <
1:<BR>
c.socket.sendall("
")<BR>
else:<BR>
msgs =
""<BR>
for q in
c.queue:<BR>
msgs += q +
'\n'<BR>
# send queued
messages<BR>
c.socket.sendall(msgs)<BR>
c.queue =
[]<BR>
print "Sent all pending messages for " +
c.user<BR>
else:<BR>
socket.sendall(" ")</DIV>
<DIV> </DIV>
<DIV> # if
message packet, extract data and append to target
queue<BR> if
receivedData.startswith('###',0,3):<BR>
print "Received message
packet"<BR>
receivedData = receivedData.replace('###', '',
1).lstrip()<BR>
l =
receivedData.split('##',1)<BR>
src =
l[0]<BR>
text =
l[1]<BR>
if text.strip !=
"":<BR>
print "Message not
empty"<BR>
# extract
client<BR>
clientSrc =
_clients[src]<BR>
# ...and its
buddy<BR>
clientDest =
_clients[clientSrc.buddy]<BR>
msg = src+":
"+text<BR>
print "Appended message to queue of " +
clientSrc.buddy<BR>
clientDest.queue.append(msg)<BR>
print "Queue of: " + clientDest.user + " = %s" %
clientDest.queue<BR>
clientDest.socket.sendall("
")<BR>
else:<BR>
if len(_clients) <
2:<BR>
self.request.sendall(receivedData)</DIV>
<DIV> </DIV>
<DIV> for c in
_clients.values():<BR>
if self.request ==
c.socket:<BR>
c.socket.close()<BR>
# remove from
hashmap<BR>
del
_clients[c.user]<BR>
print "Removed " + c.user + " from hashmap"</DIV>
<DIV> </DIV>
<DIV> print "Disconnected from",
self.client_address<BR> <BR>srv =
SocketServer.ThreadingTCPServer(('',_port),Broker)<BR>print "Started IIM server
on port %d" % _port<BR>srv.serve_forever()</DIV>
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