Right way to connect with mongrel2 server REQ/REP

zmq_hello.py

# FROM: https://github.com/zeromq/pyzmq/issues/132
#
# You need to set LINGER to something other than -1 (the default) if
# you want the socket to stop trying to send. The gist is that you
# should be able to do:
#
#    socket.send('foo')
#    socket.close()
#
# and close() will block until the socket is done sending messages. 
# Since your peer never arrives, the socket keeps waiting. LINGER
# is the amount of time (in ms) that it will block. The default is
# -1, or forever. setsockopt(LINGER, 0) means close() will drop
# everything and return right away.

import zmq
    
INVALID_ADDR = 'ipc:///tmp/idontexist.socket'
    
context = zmq.Context()
socket = context.socket(zmq.REQ)
    
# zmq.LINGER is timeout of zmq.send()
socket.setsockopt(zmq.LINGER, 0)
    
socket.connect(INVALID_ADDR)
try:
    socket.send('hello')
    
    poller = zmq.Poller()
    poller.register(socket, zmq.POLLIN)
    conn = dict(poller.poll(1000))
    if conn:
        if conn.get(socket) == zmq.POLLIN:
            print "got result: ", socket.recv(zmq.NOBLOCK)
    else:
        print 'got no result'
finally:
    socket.close()
    context.term()