#!/usr/bin/env python
# -*- Mode: Python; -*-
## Tiny Syslog Server in Python.
##
## This is a tiny syslog server that is able to receive UDP based syslog
## entries on a specified port and save them to a file.
## That's it... it does nothing else...
import os
import sys, os, time, atexit
from signal import SIGTERM
import logging
import logging.handlers
import SocketServer
import datetime
from subprocess import call
import argparse
import os
import socket
## code to determine this host's IP on non-loopback interface
if os.name != "nt":
import fcntl
import struct
def get_interface_ip(ifname):
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
return socket.inet_ntoa(fcntl.ioctl(s.fileno(), 0x8915, struct.pack('256s',
ifname[:15]))[20:24])
def get_lan_ip():
ip = socket.gethostbyname(socket.gethostname())
if ip.startswith("127.") and os.name != "nt":
interfaces = [
"eth0",
"eth1",
"eth2",
"wlan0",
"wlan1",
"wifi0",
"ath0",
"ath1",
"ppp0",
]
for ifname in interfaces:
try:
ip = get_interface_ip(ifname)
break
except IOError:
pass
return ip
class Daemon(object):
"""
A generic daemon class.
Usage: subclass the Daemon class and override the run() method
"""
def __init__(self, pidfile, stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
self.stdin = stdin
self.stdout = stdout
self.stderr = stderr
self.pidfile = pidfile
def daemonize(self):
"""
do the UNIX double-fork magic, see Stevens' "Advanced
Programming in the UNIX Environment" for details (ISBN 0201563177)
http://www.erlenstar.demon.co.uk/unix/faq_2.html#SEC16
"""
try:
pid = os.fork()
if pid > 0:
# exit first parent
sys.exit(0)
except OSError, e:
sys.stderr.write("fork #1 failed: %d (%s)\n" % (e.errno, e.strerror))
sys.exit(1)
# decouple from parent environment
os.chdir("/")
os.setsid()
os.umask(0)
# do second fork
try:
pid = os.fork()
if pid > 0:
# exit from second parent
sys.exit(0)
except OSError, e:
sys.stderr.write("fork #2 failed: %d (%s)\n" % (e.errno, e.strerror))
sys.exit(1)
# redirect standard file descriptors
sys.stdout.flush()
sys.stderr.flush()
si = file(self.stdin, 'r')
so = file(self.stdout, 'a+')
se = file(self.stderr, 'a+', 0)
os.dup2(si.fileno(), sys.stdin.fileno())
os.dup2(so.fileno(), sys.stdout.fileno())
os.dup2(se.fileno(), sys.stderr.fileno())
# write pidfile
atexit.register(self.delpid)
pid = str(os.getpid())
file(self.pidfile,'w+').write("%s\n" % pid)
def delpid(self):
os.remove(self.pidfile)
def start(self):
"""
Start the daemon
"""
# Check for a pidfile to see if the daemon already runs
try:
pf = file(self.pidfile,'r')
pid = int(pf.read().strip())
pf.close()
except IOError:
pid = None
if pid:
message = "pidfile %s already exist. Daemon already running?\n"
sys.stderr.write(message % self.pidfile)
sys.exit(1)
# Start the daemon
self.daemonize()
self.run()
def stop(self):
"""
Stop the daemon
"""
# Get the pid from the pidfile
try:
pf = file(self.pidfile,'r')
pid = int(pf.read().strip())
pf.close()
except IOError:
pid = None
if not pid:
message = "pidfile %s does not exist. Daemon not running?\n"
sys.stderr.write(message % self.pidfile)
return # not an error in a restart
# Try killing the daemon process
try:
while 1:
os.kill(pid, SIGTERM)
time.sleep(0.1)
except OSError, err:
err = str(err)
if err.find("No such process") > 0:
if os.path.exists(self.pidfile):
os.remove(self.pidfile)
else:
print str(err)
sys.exit(1)
def restart(self):
"""
Restart the daemon
"""
self.stop()
self.start()
def run(self):
"""
You should override this method when you subclass Daemon. It will be called after the process has been
daemonized by start() or restart().
"""
# setup logging module so that the log can be moved aside and will reopen for append
def log_setup(logfile):
log_handler = logging.handlers.WatchedFileHandler(logfile)
formatter = logging.Formatter(
'%(message)s','')
log_handler.setFormatter(formatter)
logger = logging.getLogger()
logger.addHandler(log_handler)
logger.setLevel(logging.INFO)
class SyslogUDPHandler(SocketServer.BaseRequestHandler):
def handle(self):
data = bytes.decode(self.request[0].strip())
socket = self.request[1]
print( "%s : " % self.client_address[0], str(data))
timestamp = datetime.datetime.now().isoformat()
logline = timestamp + ":"+self.client_address[0] + ":" + str(data)
logging.info(str(logline))
class TelemetryLogDaemon(Daemon):
def __init__(self, pidfile, logfile, server_ip, server_port):
self.logfile = logfile
self.server_ip = server_ip
self.server_port = server_port
super(TelemetryLogDaemon, self).__init__(pidfile)
def run(self):
log_setup(self.logfile)
server = SocketServer.UDPServer((self.server_ip,int(self.server_port)), SyslogUDPHandler)
server.serve_forever(poll_interval=0.5)
def main():
default_log_file = os.environ['PWD'] + "/telemetry.log"
parser = argparse.ArgumentParser(description = 'telemetry-daemon')
actions="start,restart,stop,nodaemon".split(",")
parser.add_argument("-a", "--action", required=True, choices=actions, help="manage daemon: start stop or restart")
parser.add_argument("-p", "--server-port", default="5929", help="specify alternate udp port number, default is 5929")
parser.add_argument("-i", "--server-ip", default=get_lan_ip(), help="specify IP if heuristics to get local host lan ip fails")
parser.add_argument("-l", "--log-file", default=default_log_file, help="specify log file to write")
parser.add_argument("-z", "--pid-file", default=default_log_file + ".pidfile", help="specify pidfile")
opts = parser.parse_args()
tld = TelemetryLogDaemon(opts.pid_file, opts.log_file, opts.server_ip, opts.server_port)
if opts.action == "start":
print "Info: Starting server"
print """Example addition to megatest.config to enable telemetry:
[telemetry]
host %s
port %s
want-events ALL
""" % (opts.server_ip, opts.server_port)
tld.start()
elif opts.action == "stop":
tld.stop()
elif opts.action == "restart":
print "Info: Restarting server"
print """Example addition to megatest.config to enable telemetry:
[telemetry]
host %s
port %s
want-events ALL
""" % (opts.server_ip, opts.server_port)
tld.restart()
elif opts.action == "nodaemon":
log_setup(opts.log_file)
server = SocketServer.UDPServer((opts.server_ip,int(opts.server_port)), SyslogUDPHandler)
server.serve_forever(poll_interval=0.5)
if __name__ == '__main__':
main()