#
# Freelance Client - Model 2
# Uses DEALER socket to blast one or more services
#
# Author: Daniel Lundin <dln(at)eintr(dot)org>
#
import sys
import time
import zmq
GLOBAL_TIMEOUT = 2500 # ms
class FLClient(object):
def __init__(self):
self.servers = 0
self.sequence = 0
self.context = zmq.Context()
self.socket = self.context.socket(zmq.DEALER) # DEALER
def destroy(self):
self.socket.setsockopt(zmq.LINGER, 0) # Terminate early
self.socket.close()
self.context.term()
def connect(self, endpoint):
self.socket.connect(endpoint)
self.servers += 1
print "I: Connected to %s" % endpoint
def request(self, *request):
# Prefix request with sequence number and empty envelope
self.sequence += 1
msg = ['', str(self.sequence)] + list(request)
# Blast the request to all connected servers
for server in xrange(self.servers):
self.socket.send_multipart(msg)
# Wait for a matching reply to arrive from anywhere
# Since we can poll several times, calculate each one
poll = zmq.Poller()
poll.register(self.socket, zmq.POLLIN)
reply = None
endtime = time.time() + GLOBAL_TIMEOUT / 1000
while time.time() < endtime:
socks = dict(poll.poll((endtime - time.time()) * 1000))
if socks.get(self.socket) == zmq.POLLIN:
reply = self.socket.recv_multipart()
assert len(reply) == 3
sequence = int(reply[1])
if sequence == self.sequence:
break
return reply
if len(sys.argv) == 1:
print "I: Usage: %s <endpoint> …" % sys.argv[0]
sys.exit(0)
# Create new freelance client object
client = FLClient()
for endpoint in sys.argv[1:]:
client.connect(endpoint)
start = time.time()
for requests in xrange(10000):
request = "random name"
reply = client.request(request)
if not reply:
print "E: Name service not available, aborting"
break
print "Average round trip cost: %i usec" % ((time.time() - start) / 100)
client.destroy()