[Pythonmac-SIG] Lost connection

[bob ackerman]

--Boundary_(ID_2bmEYc/Q91pBu1Upm+37Sw)
Content-type: text/plain; charset=US-ASCII; format=flowed
Content-transfer-encoding: 7BIT


On Saturday, April 27, 2002, at 09:53  PM, broz wrote:

> Hi folks,
>
> The solution to my problem could very well seem obvious, but to me it's 
> not
> obvious.
>
> I've got a python application that opens a socket, receives data (XML),
> parses it, and updates a database. Under normal circumstances, it all 
> works
> just fine. Under abnormal circumstances, it sits and spins.
>
> The main application opens a socket with listen(), and then accept() is
> called. It dutifully waits for the other machine to connect() and start
> dumping data. That process works fine. If the other machine drops the 
> line,
> things get hairy. My python app thinks the connection is still live, and
> spins waiting for more data. I'm just doing a socket.recv(2048) to get the
> data. I would have expected an error to be thrown if the connection 
> failed,
> but no error is thrown.

i don't think you should be doing a listen in socketSetup.
i don't think that would cause your problem, but it might help to take it 
out.


> Odd.
>
> What I need to do is discover the connection went down, and open a new one
> when the server on the other end comes back.
>
> I'm running this on Mac OS X. How can I tell the connection went down?
>
> Thanks in advance.
>
>
> def socketSetup(self, thePort):
>
>         try:
>             self.theSock = socket(AF_INET, SOCK_STREAM)
>
>             self.theSock.bind(('', thePort))
>             self.theSock.listen(5)
>         except Exception, theErr:
>             self.logger.logStatus( "connection failed: " + str(theErr))
>
>     def socketConnect(self):
>         " this is where we accept the connection from the server"
>         print "in socketConnect"
>         try:
>             if not self.theSock:
>                 print "theSock is None!"
>             else:
>                 self.theConnection, theAddress = self.theSock.accept()
>                 self.connected = 1
>
>         except socket.error, theErr:
>             self.connected = 0
>             print "socketConnect error - " + str(error) + ": " + 
> str(theErr)
>
>     def getConnectStatus(self):
>         return self.connected
>
>     def getData(self):
>         "handle data feeds from either a file or a socket"
>         # print "getData called"
>         try:
>             if self.connected:
>
>                 self.theData = self.theConnection.recv(2048)
>             else:
>                 self.socketConnect()
>
>             return self.theData
>         except Exception, theErr:
>             print ("getData error: " + theErr)
>             self.logger.log("getData error: " + theErr)
>
>
>
> --
>
> Richard Brosnahan
> Editor in Chief
> Broz News
> Hand Picked Technical News
> Updated Every Business Day!
> http://broznews.com/
>
>
>
>
> _______________________________________________
> Pythonmac-SIG maillist  -  Pythonmac-SIG@python.org
> http://mail.python.org/mailman/listinfo/pythonmac-sig
>

--Boundary_(ID_2bmEYc/Q91pBu1Upm+37Sw)
Content-type: text/enriched; charset=US-ASCII
Content-transfer-encoding: 7BIT


On Saturday, April 27, 2002, at 09:53  PM, broz wrote:


<excerpt>Hi folks,


The solution to my problem could very well seem obvious, but to me
it's not

obvious.


I've got a python application that opens a socket, receives data (XML),

parses it, and updates a database. Under normal circumstances, it all
works

just fine. Under abnormal circumstances, it sits and spins.


The main application opens a socket with listen(), and then accept() is

called. It dutifully waits for the other machine to connect() and start

dumping data. That process works fine. If the other machine drops the
line,

things get hairy. My python app thinks the connection is still live,
and

spins waiting for more data. I'm just doing a socket.recv(2048) to get
the

data. I would have expected an error to be thrown if the connection
failed,

but no error is thrown.

</excerpt>

i don't think you should be doing a listen in
<color><param>0000,0000,DEDE</param>socketSetup</color>.

i don't think that would cause your problem, but it might help to take
it out.



<excerpt>Odd.


What I need to do is discover the connection went down, and open a new
one

when the server on the other end comes back.


I'm running this on Mac OS X. How can I tell the connection went down?


Thanks in advance.



def socketSetup(self, thePort):


        try:

            self.theSock = socket(AF_INET, SOCK_STREAM)


            self.theSock.bind(('', thePort))

            self.theSock.listen(5)

        except Exception, theErr:

            self.logger.logStatus( "connection failed: " + str(theErr))


    def socketConnect(self):

        " this is where we accept the connection from the server"

        print "in socketConnect"

        try: 

            if not self.theSock:

                print "theSock is None!"

            else:

                self.theConnection, theAddress = self.theSock.accept()

                self.connected = 1


        except socket.error, theErr:

            self.connected = 0

            print "socketConnect error - " + str(error) + ": " +
str(theErr)


    def getConnectStatus(self):

        return self.connected


    def getData(self):

        "handle data feeds from either a file or a socket"

        # print "getData called"

        try:

            if self.connected:


                self.theData = self.theConnection.recv(2048)

            else:

                self.socketConnect()


            return self.theData

        except Exception, theErr:

            print ("getData error: " + theErr)

            self.logger.log("getData error: " + theErr)




-- 


Richard Brosnahan

Editor in Chief

Broz News

Hand Picked Technical News

Updated Every Business Day!

http://broznews.com/





_______________________________________________

Pythonmac-SIG maillist  -  Pythonmac-SIG@python.org

http://mail.python.org/mailman/listinfo/pythonmac-sig


</excerpt>

--Boundary_(ID_2bmEYc/Q91pBu1Upm+37Sw)--