Socket Help

[Lindstrom Greg - glinds]

Hello-

I have a python routine (Python 2.2.3 on Windows 2000 "Professional") using
a socket connection. Problem is, the backend service I'm connecting to will
hang every so often and the socket will simply wait for a response which
will never come. I'm thinking of putting in a routine to check the socket's
status, which now brings in threading. Before I go to the trouble I thought
I'd ask if there is a simple way to verify my socket is still communicating.
It's running about 200 transactions per second...if I put in the threaded
timer I'd have it take a look every few seconds to see if the
"TotalRecordsProcessed" counter has been incremented.

Your constructive thoughts are requested.

Thanks!

--greg

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[Stewart Midwinter]

Lindstrom Greg - glinds <Gr************@acxiom.com> wrote in message news:<ma*************************************@pyth on.org>...

I'd ask if there is a simple way to verify my socket is still communicating.

how about this, taken from a non-blocking socket class's Connect method:

class NBSocket:
def __init__(self):
self.__host = 'localhost'
self.__port = 177
self.__myconnection = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
self.__myconnection.setsockopt(0,socket.SO_KEEPALI VE,1)
self.__connected = 0
return

def connect(self, host = 'localhost', port = 177, applicationName = 'NBSocket'):
"""
================================================== ====================c+
NBSocket.connect(self,host,port,applicationName)

This procedure opens the connection to the socket defined in __init__
it takes the host name, prot number and application name as aruguments
host defaults to localhost
port defaults to 177
application name defaults to None
It tries to connect once and if it doesn't get a response after 5
seconds or if it can't connect right away it raises a socket.error
exception
================================================== ====================c-
"""
# Test to see if we are already connected
if self.__connected:
print "This socket is already connected"
return 1
self.__host = host
self.__port = int(port)
self.__applicationName = applicationName
counter = 0
try:

failed = 1
while failed:
try:
self.__myconnection.recv(1024)
self.__connected = 1
self.__myconnection.setblocking(1)
failed = 0
print 'connected'
except socket.error:
print 'unable to connect'
counter = counter + 1
time.sleep(1)
if counter > 5:
raise
except socket.error:
raise

then continue on with your communication with the server...

cheers,
S

[Luca Fini]

Python 2.3 has support for timeout on sockets.

l.f.

On Mon, 29 Mar 2004, Lindstrom Greg - glinds wrote:

Hello-

I have a python routine (Python 2.2.3 on Windows 2000 "Professional") using
a socket connection. Problem is, the backend service I'm connecting to will
hang every so often and the socket will simply wait for a response which
will never come. I'm thinking of putting in a routine to check the socket's
status, which now brings in threading. Before I go to the trouble I thought
I'd ask if there is a simple way to verify my socket is still communicating.
It's running about 200 transactions per second...if I put in the threaded
timer I'd have it take a look every few seconds to see if the
"TotalRecordsProcessed" counter has been incremented.

Your constructive thoughts are requested.

--------------------------------------------------------------------------
-- ) Luca Fini Tel: [phone]
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(_) (_) Italia / e-mail: lf***@arcetri.astro.it
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