I have a Python script that runs in an infinite loop (it's a server).
I want to write an AppleScript that will start this script if it isn't started yet, and otherwise force-quit and restart it. This will make it easy for me to make changes to the server code while programming.
Currently I only know how to start it: do shell script "python server.py"
Note that AppleScript's do shell script starts the shell (/bin/sh) in the root directory (/) by default, so you should specify an explicit path to server.py
In the following examples I'll assume directory path ~/srv.
Here's the shell command:
pid=$(pgrep -fx 'python .*/server\.py'); [ "$pid" ] && kill -9 $pid; python ~/srv/server.py
As an AppleScript statement, wrapped in do shell script - note the \-escaped inner " and \ chars.:
do shell script "pid=$(pgrep -fx 'python .*/server\\.py'); [ \"$pid\" ] && kill -9 $pid; python ~/srv/server.py"
pgrep -fx '^python .*/server\.py$' uses pgrep to find your running command by regex against the full command line (-f), requiring a full match (-x), and returns the PID (process ID), if any.
Note that I've used a more abstract regex to underscore the fact that pgrep (always) treats its search term as a regular expression.
To specify the full launch command line as the regex, use python ~/srv/server\.py - note the \-escaping of . for full robustness.
[ "$pid" ] && kill -9 $pid kills the process, if a PID was found ([ "$pid" ] is short for [ -n "$pid" ] and evaluates to true only if $pid is nonempty); -9 sends signal SIGKILL, which forcefully terminates the process.
python ~/srv/server.py then (re)starts your server.
On the shell, if you do ps aux | grep python\ server.py | head -n1, you'll get the ID of the process running server.py. You can then use kill -9 to kill that process and restart it:
kill -9 `ps aux | grep python\ server.py | head -n1 | python -c 'import sys; print(sys.stdin.read().split()[1])'`
That'll kill it. Al you have to do now is to restart it:
python server.py
You can combine the two with &&:
kill -9 `ps aux | grep python\ server.py | head -n1 | python -c 'import sys; print(sys.stdin.read().split()[1])'` && python server.py
Of course, you already know how to put that in a do shell script!
Related
I have running python file "cepusender/main.py" (and another python files). How can I restart/kill only main.py file?
Here's a way (there are many):
ps -ef | grep 'cepusender/main.py' | grep -v grep | awk '{print $2}' | xargs kill
ps is the process snapshot command. -e prints every process on the system, and -f prints the full-format listing, which, germanely, includes the command line arguments of each process.
grep prints lines matching a pattern. We first grep for your file, which will match both the python process and the grep process. We then grep -v (invert match) for grep, paring output down to just the python process.
Output now looks like the following:
user 77864 68024 0 13:53 pts/4 00:00:00 python file.py
Next, we use awk to pull out just the second column of the output, which is the process ID or PID.
Finally we use xargs to pass the PID to kill, which asks the python process to shutdown gracefully.
kill is the command to send signals to processes.
You can use kill -9 PID to kill your python process, where 9 is the number for SIGKILL and PID is the python Process ID.
I'm a brand new noob in python universe, so don't judge me too fast :-)
I'm trying to force a python script to reload or restart at the beggining of a bash script.
I've tried :
pkill -f myscript.py
and
killall myscript.py
and others...
Actually, I would like to make run the same script that call .wav files after having changed those .wav files... If I don't reload the script or restart it, it keeps playing the old files.
Maybe, there is other solutions.
Here is the script I want to reload (it's a button script playing music for my daughter)
#!/usr/bin/env python3
import pygame
from gpiozero import LED, Button
from signal import pause
pygame.init()
button_sounds = {Button(2): pygame.mixer.Sound("/home/pi/gpio-music-box/samples/1.wav"),
Button(3): pygame.mixer.Sound("/home/pi/gpio-music-box/samples/2.wav"),
Button(4): pygame.mixer.Sound("/home/pi/gpio-music-box/samples/3.wav"),
Button(17): pygame.mixer.Sound("/home/pi/gpio-music-box/samples/4.wav")}
for button, sound in button_sounds.items():
button.when_pressed = sound.play
pause()
And here is my bash script :
#!/bin/bash
***HERE THE COMMAND I NEED !***
rm -r /home/pi/gpio-music-box/samples/*
cp -r /home/pi/gpio-music-box/comptines/* /home/pi/gpio-music-box/samples/
/home/pi/gpio-music-box/music.py
Thank you very much, and scuze my english, I'm french :-)
Andy
try this
#!/bin/bash
pid=$(ps auxwww | grep nameOfScript.py | grep -v grep | awk '{print $2}')
kill -9 $pid
rm -r /home/pi/gpio-music-box/samples/*
cp -r /home/pi/gpio-music-box/comptines/* /home/pi/gpio-music-box/samples/
nohup /home/pi/gpio-music-box/music.py &
Have a nice day
Firstly, you can reduce a lot of the "noise" from ps by using output formatting. You can then stop the need for using both grep and awk by using awk to do the searching also.
ps -eo "%p %a" | awk '/nameOfScript.py/ && $1 != PROCINFO["pid"] { print "kill -9 "$1 }'
This forces ps to only print the pid (%p) and the full command (%a). The output is then piped to awk where is searches for lines with the name of the script contained. It discounts any entries with the current process id of awk and then uses this to print a kill command with the relevant process id.
Once you have verified that the kill command displays as expected, you can use awk's system function to actually run the command through:
ps -eo "%p %a" | awk '/prometheous-things.py/ && $1 != PROCINFO["pid"] { system("kill -9 "$1) }'
Is it possible to tag a python program run from the command line?
Context: Said command will be run with nohup in the background, and will be killed and restarted at midnight via cron. My intention is to pipe ps into egrep for said tag, grab the pid, and kill -9 before restarting.
minimal, complete, and verifiable example
Start a python web server:
$ nohup python -m http.server 8888 &
Add a tag to the command. Note that -tag is just my imagination at work.. this is what I want:
$ nohup python -m http.server 8888 & -tag "ced72ca0-cd19-11ea-87d0-0242ac130003"
grep for tag:
$ ps aux | egrep "ced72ca0-cd19-11ea-87d0-0242ac130003"
...grab the pid from this, and kill -9
Because you're saying that you want to kill the processes through isolated cron jobs at nidnight, I guess that the $! based solutions in the linked questions (like (How to get the process ID to kill a nohup process?)) are no option for you.
In order to identity your HTTP server processes, your idea is to 'tag' them with a unique ID so the cron jobs will find them.
What you could do in your specific case is to make use of the fact that the listening TCP sockets are unique on your given machine, and retrieve the associated pid through netstat.
A bash script along the lines of:
#!/bin/bash
port=${1:-"8888"}
IP=${2:-"0.0.0.0"}
pid=`netstat -antp 2>/dev/null | grep -E "^(\S+\s+){3}$IP:$port\s+\S+\s+LISTEN" | sed -E 's/ˆ(\S+\s+){6}([0-9]+).*$/\2/'`
[[ -n "$pid" ]] && kill -TERM $pid
... that you parameterize with IP and port through your cronjob.
You can put code in file with name ced72ca0-cd19-11ea-87d0-0242ac130003,
#!/bin/bash
python -m http.server
set it executable
chmod +x ced72ca0-cd19-11ea-87d0-0242ac130003
run it
nohup ced72ca0-cd19-11ea-87d0-0242ac130003 &
and then you can kill it
pkill ced72ca0-cd19-11ea-87d0-0242ac130003
or even using only beginning of filename
pkill ced
EDIT:
Because new script doesn't get any arguments so you can run it with any argument(s) - ie. some tag/word
nohup ced72ca0-cd19-11ea-87d0-0242ac130003 hello_world &
and then you can kill it using -f
pkill -f hello_world
or even using part of word
pkill -f hello
pkill -f world
This way you can even use normal name for script and add tag
nohup my_script ced72ca0-cd19-11ea-87d0-0242ac130003 &
and kill with -f
pkill -f ced72ca0-cd19-11ea-87d0-0242ac130003
or using only part of word
pkill -f ced
I'm not familiar with bash at all, but I'm trying to make a pair of scripts that will detect
If a program is running.
If a python/bash script is running.
My code for nº1 is:
#!/bin/bash
X=$( pidof $1 )
if [ ${#X} -gt 0 ]
then
echo "$1 has already $X been started"
else
echo "$1 not started $X"
fi
Which works great, but won't detect scripts, so I made nº 2 with the change:
X=$( pgrep -f $1 )
At first nº2 it seemed to be working, but when I terminated the python script I still get:
WebsocketServer has 5 length and it's already 11919 started
If I do ps -ax the PID of the processes aren't nowhere to be seen.
But if I write ps -ax | grep websocket:
11921 pts/4 S+ 0:00 grep --color=auto websocket
If I start the python script...
WebsocketServer has 11 length and it's already 11927 11935 started
What is happening? Am I somehow misusing the commands?
Edit: Forgot to mention that writing pgrep -f WebsocketServer in the terminal returns nothing, like it should.
The problem is that the argument to your script is the same as the script name you're searching for, and pgrep -f is finding the script.
Here's a trick you can try: split the name into two arguments.
checkScriptAlive websocket Server
Then in the script, do:
target="$1$2"
x=$(pgrep -f "$target")
I run a bash script with which start a python script to run in background
#!/bin/bash
python test.py &
So how i can i kill the script with bash script also?
I used the following command to kill but output no process found
killall $(ps aux | grep test.py | grep -v grep | awk '{ print $1 }')
I try to check the running processes by ps aux | less and found that the running script having command of python test.py
Please assist, thank you!
Use pkill command as
pkill -f test.py
(or) a more fool-proof way using pgrep to search for the actual process-id
kill $(pgrep -f 'python test.py')
Or if more than one instance of the running program is identified and all of them needs to be killed, use killall(1) on Linux and BSD
killall test.py
You can use the ! to get the PID of the last command.
I would suggest something similar to the following, that also check if the process you want to run is already running:
#!/bin/bash
if [[ ! -e /tmp/test.py.pid ]]; then # Check if the file already exists
python test.py & #+and if so do not run another process.
echo $! > /tmp/test.py.pid
else
echo -n "ERROR: The process is already running with pid "
cat /tmp/test.py.pid
echo
fi
Then, when you want to kill it:
#!/bin/bash
if [[ -e /tmp/test.py.pid ]]; then # If the file do not exists, then the
kill `cat /tmp/test.py.pid` #+the process is not running. Useless
rm /tmp/test.py.pid #+trying to kill it.
else
echo "test.py is not running"
fi
Of course if the killing must take place some time after the command has been launched, you can put everything in the same script:
#!/bin/bash
python test.py & # This does not check if the command
echo $! > /tmp/test.py.pid #+has already been executed. But,
#+would have problems if more than 1
sleep(<number_of_seconds_to_wait>) #+have been started since the pid file would.
#+be overwritten.
if [[ -e /tmp/test.py.pid ]]; then
kill `cat /tmp/test.py.pid`
else
echo "test.py is not running"
fi
If you want to be able to run more command with the same name simultaneously and be able to kill them selectively, a small edit of the script is needed. Tell me, I will try to help you!
With something like this you are sure you are killing what you want to kill. Commands like pkill or grepping the ps aux can be risky.
ps -ef | grep python
it will return the "pid" then kill the process by
sudo kill -9 pid
eg output of ps command:
user 13035 4729 0 13:44 pts/10 00:00:00 python (here 13035 is pid)
With the use of bashisms.
#!/bin/bash
python test.py &
kill $!
$! is the PID of the last process started in background. You can also save it in another variable if you start multiple scripts in the background.
killall python3
will interrupt any and all python3 scripts running.