zhelpers.py

# encoding: utf-8
"""
Helper module for example applications. Mimics ZeroMQ Guide's zhelpers.h.
"""

import binascii
import os
from random import randint

import zmq

# fix ROUTER/DEALER aliases, missing from pyzmq < 2.1.9
if not hasattr(zmq, 'ROUTER'):
	zmq.ROUTER = zmq.XREP
if not hasattr(zmq, 'DEALER'):
	zmq.DEALER = zmq.XREQ


# Receives all message parts from socket, prints neatly
def dump(msg_or_socket):
	if isinstance(msg_or_socket, zmq.Socket):
		# it's a socket, call on current message
		return dump(msg_or_socket.recv_multipart())
	else:
		msg = msg_or_socket
	print("----------------------------------------")
	for part in msg:
		part = part.decode()
		print("[%03d]" % len(part), end=' ')
		is_text = True
		for c in part:
			if ord(c) < 32 or ord(c) > 128:
				is_text = False
				break
		if is_text:
			# print only if ascii text
			print(part)
		else:
			# not text, print hex
			print(binascii.hexlify(part))
	return msg


# Set simple random printable identity on socket
def set_id(zsocket):
	identity = "%04x-%04x" % (randint(0, 0x10000), randint(0, 0x10000))
	zsocket.setsockopt(zmq.IDENTITY, identity)

def zpipe(ctx):
	"""build inproc pipe for talking to threads
	
	mimic pipe used in czmq zthread_fork.
	
	Returns a pair of PAIRs connected via inproc
	"""
	a = ctx.socket(zmq.PAIR)
	a.linger = 0
	b = ctx.socket(zmq.PAIR)
	b.linger = 0
	a.hwm = 1
	b.hwm = 1
	iface = "inproc://%s" % binascii.hexlify(os.urandom(8))
	a.bind(iface)
	b.connect(iface)
	return a,b