I want to run a python script in a CENTOS server:
#!/usr/bin/env python
import socket
try:
import thread
except ImportError:
import _thread as thread #Py3K changed it.
class Polserv(object):
def __init__(self):
self.numthreads = 0
self.tidcount = 0
self.port = 843
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.sock.bind(('100.100.100.100', self.port))
self.sock.listen(5)
def run(self):
while True:
thread.start_new_thread(self.handle, self.sock.accept())
def handle(self,conn,addr):
self.numthreads += 1
self.tidcount += 1
tid=self.tidcount
while True:
data=conn.recv(2048)
if not data:
conn.close()
self.numthreads-=1
break
#if "<policy-file-request/>\0" in data:
conn.sendall(b"<?xml version='1.0'?><cross-domain-policy><allow-access-from domain='*' to-ports='*'/></cross-domain-policy>")
conn.close()
self.numthreads-=1
break
#conn.sendall(b"[#%d (%d running)] %s" % (tid,self.numthreads,data) )
Polserv().run()
Im using $ python flashpolicyd.py and it works fine...
The question is: How to keep this script running even after I close the terminal(console)?
I use this code to daemonize my applications. It allows you start/stop/restart the script using the following commands.
python myscript.py start
python myscript.py stop
python myscript.py restart
In addition to this I also have an init.d script for controlling my service. This allows you to automatically start the service when your operating system boots-up.
Here is a simple example to get your going. Simply move your code inside a class, and call it from the run function inside MyDeamon.
import sys
import time
from daemon import Daemon
class YourCode(object):
def run(self):
while True:
time.sleep(1)
class MyDaemon(Daemon):
def run(self):
# Or simply merge your code with MyDaemon.
your_code = YourCode()
your_code.run()
if __name__ == "__main__":
daemon = MyDaemon('/tmp/daemon-example.pid')
if len(sys.argv) == 2:
if 'start' == sys.argv[1]:
daemon.start()
elif 'stop' == sys.argv[1]:
daemon.stop()
elif 'restart' == sys.argv[1]:
daemon.restart()
else:
print "Unknown command"
sys.exit(2)
sys.exit(0)
else:
print "usage: %s start|stop|restart" % sys.argv[0]
sys.exit(2)
Upstart
If you are running an operating system that is using Upstart (e.g. CentOS 6) - you can also use Upstart to manage the service. If you use Upstart you can keep your script as is, and simply add something like this under /etc/init/my-service.conf
start on started sshd
stop on runlevel [!2345]
exec /usr/bin/python /opt/my_service.py
respawn
You can then use start/stop/restart to manage your service.
e.g.
start my-service
stop my-service
restart my-service
A more detailed example of working with upstart is available here.
Systemd
If you are running an operating system that uses Systemd (e.g. CentOS 7) you can take a look at the following Stackoverflow answer.
I offer two recommendations:
1) Install the supervisor package (more verbose instructions here):
sudo apt-get install supervisor
2) Create a config file for your daemon at /etc/supervisor/conf.d/flashpolicyd.conf:
[program:flashpolicyd]
directory=/path/to/project/root
environment=ENV_VARIABLE=example,OTHER_ENV_VARIABLE=example2
command=python flashpolicyd.py
autostart=true
autorestart=true
3) Restart supervisor to load your new .conf
supervisorctl update
supervisorctl restart flashpolicyd
[Unit]
Description=My Python daemon
[Service]
Type=simple
ExecStart=/usr/bin/python3 /opt/project/main.py
WorkingDirectory=/opt/project/
Environment=API_KEY=123456789
Environment=API_PASS=password
Restart=always
RestartSec=2
[Install]
WantedBy=sysinit.target
Place this file into /etc/systemd/system/my_daemon.service and enable it using systemctl daemon-reload && systemctl enable my_daemon && systemctl start my_daemon --no-block.
To view logs:
systemctl status my_daemon
first import os module in your app than with use from getpid function get pid's app and save in a file.for example :
import os
pid = os.getpid()
op = open("/var/us.pid","w")
op.write("%s" % pid)
op.close()
and create a bash file in /etc/init.d path: /etc/init.d/servername
PATHAPP="/etc/bin/userscript.py &"
PIDAPP="/var/us.pid"
case $1 in
start)
echo "starting"
$(python $PATHAPP)
;;
stop)
echo "stoping"
PID=$(cat $PIDAPP)
kill $PID
;;
esac
now , u can start and stop ur app with down command:
service servername stop service servername start
or
/etc/init.d/servername stop /etc/init.d/servername start
My non pythonic approach would be using & suffix. That is:
python flashpolicyd.py &
To stop the script
killall flashpolicyd.py
also piping & suffix with disown would put the process under superparent (upper):
python flashpolicyd.pi & disown
for my script of python, I use...
To START python script :
start-stop-daemon --start --background --pidfile $PIDFILE --make-pidfile --exec $DAEMON
To STOP python script :
PID=$(cat $PIDFILE)
kill -9 $PID
rm -f $PIDFILE
P.S.: sorry for poor English, I'm from CHILE :D
Source: Stackoverflow.com