"""Demonstrate using zmq.proxy device for message relay"""
# This example is placed in the Public Domain
# It may also be used under the Creative Commons CC-0 License, (C) PyZMQ Developers

from __future__ import print_function

from threading import Thread
import time

import zmq

MSGS = 10
PRODUCERS = 2

def produce(url, ident):
    """Produce messages"""
    ctx = zmq.Context.instance()
    s = ctx.socket(zmq.PUSH)
    s.connect(url)
    print("Producing %s" % ident)
    for i in range(MSGS):
        s.send((u'%s: %i' % (ident, time.time())).encode('utf8'))
        time.sleep(1)
    print("Producer %s done" % ident)
    s.close()

def consume(url):
    """Consume messages"""
    ctx = zmq.Context.instance()
    s = ctx.socket(zmq.PULL)
    s.connect(url)
    print("Consuming")
    for i in range(MSGS * PRODUCERS):
        msg = s.recv()
        print(msg.decode('ascii'))
    print("Consumer done")
    s.close()

def proxy(in_url, out_url):
    ctx = zmq.Context.instance()
    in_s = ctx.socket(zmq.PULL)
    in_s.bind(in_url)
    out_s = ctx.socket(zmq.PUSH)
    out_s.bind(out_url)
    try:
        zmq.proxy(in_s, out_s)
    except zmq.ContextTerminated:
        print("proxy terminated")
        in_s.close()
        out_s.close()

in_url = 'tcp://127.0.0.1:5555'
out_url = 'tcp://127.0.0.1:5556'

consumer = Thread(target=consume, args=(out_url,))
proxy_thread = Thread(target=proxy, args=(in_url, out_url))
producers = [ Thread(target=produce, args=(in_url, i)) for i in range(PRODUCERS) ]

consumer.start()
proxy_thread.start()
[ p.start() for p in producers ]
consumer.join()
zmq.Context.instance().term()