Question

logexample.py logs over the network using logging.handlers.DatagramHandler, which pickles(protocol 1) the data it sends.

logserver.py is supposed to unpickle and print to screen, but instead it raises an error. If I use pickle.loads then KeyError: ‘\x00’ and if I use cPickle.loads its an EOFError

The files are here – http://gist.github.com/542543

Python version 2.6.5

Why is this happening?

————————–THE FIX—————————

For anyone else who might be interested, here is the fixed handler

class LogHandler(SocketServer.BaseRequestHandler):
    def handle(self):
        data = self.request[0]
        socket = self.request[1]
        out = pickle.loads(data[4:])
        record = logging.makeLogRecord(out)
        print record.msg

Answer 1

There is an example in the docs of how to use DataGramHandler – it shows that the datagram may be sent over multiple packets, which need to be reassembled at the receiving end. The first four bytes of the first packet are the length – you are passing this into pickle.loads as well as the pickled data. Use the example code instead.