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pycares mass resolver, input names on stdin
#!/usr/bin/python
# -*- coding: utf8 -*-
import sys
import os
import time
import select
import socket
import pycares
RETRIES = 3
TIMEOUT = 3
CONCURRENT = 1000
FORCED_TIMEOUT = 60
class Resolver(object):
def __init__(self):
self.chan = pycares.Channel(timeout=TIMEOUT, tries=RETRIES)
self.sent_count = 0
self.recv_count = 0
self.active_count = 0
self.error_count = 0
self.last_answer = time.time()
def process(self, ip):
self.chan.gethostbyname(ip, socket.AF_INET, self.result_cb)
self.active_count += 1
self.sent_count += 1
def result_cb(self, res, error):
self.last_answer = time.time()
self.active_count -= 1
self.recv_count += 1
if res:
try: addr = res.addresses[0]
except: addr = "UNKNOWN"
print "{0},{1}".format(res.name, addr)
else:
self.error_count += 1
def select(self):
readfds, writefds = self.chan.getsock()
canreadfds, canwritefds, _ = select.select(readfds, writefds, [], 0.001)
for rfd in canreadfds:
self.chan.process_fd(rfd, -1)
for wfd in canwritefds:
self.chan.process_fd(-1, wfd)
def close(self):
self.chan.destroy()
def main():
r = Resolver()
while True:
if r.active_count < CONCURRENT:
rfds, _, _ = select.select([sys.stdin,],[],[],0.001)
if rfds:
line = sys.stdin.readline()
if not line: break
line = line.strip()
if not line: continue
try:
r.process(line)
except Exception as e:
print >>sys.stderr, "exception gethostbyaddr", e, line
r.select()
input_done = time.time()
wait_time = TIMEOUT * (RETRIES + 1) + 1
while time.time() < r.last_answer + wait_time and r.active_count > 0 and time.time() < input_done + FORCED_TIMEOUT:
r.select()
print >>sys.stderr, "EXIT sent: {0} | recv: {1} | fail: {2} | active: {3}".format(r.sent_count, r.recv_count, r.error_count, r.active_count)
return 0
if __name__ == '__main__':
try: sys.exit(main())
except KeyboardInterrupt: pass
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