如何将交互式Python脚本作为cron作业运行？

Question

I have a Python script, say test.py which interacts with the user everytime it is executed.

test.py

#!/usr/bin/env python3

def foo():
    a = input()
    print("Hello, {}".format(a))

if __name__ == '__main__':
    foo()

I want to run this script every 5 minutes. So, I tried adding it to my crontab but it seems that this doesn't work as I am not prompted to enter an input.
I have tested my crontab and it is working fine.

Should I use libraries such as schedule for this task?
What would be the ideal way of going about in this scenario?
NOTE: I want a cross platform solution which works on MacOSX and GNU/Linux.

Answer 1

Your could try the python module pexpect ( http://pexpect.sourceforge.net/doc/ ) -- the usage is something like :

import pexpect
child = pexpect.spawn(script/python file etc...)
child.expect('Here goes the prompt you would expect')
child.sendline('What you want to send to it')

Answer 2

its not possible to have cron interact interactively on your server.

Delink your application: Setup a db (like MySQL), have test.py run via cron every 5 mins to check if a new entry is made in the db: then, have a local application that saves user prompt information to your db.

Answer 3

If it is running via cron or schedule, it will not be running on your terminal, it will run as a background process. Therefore, it cannot be interactive and you will not be prompted.

If you just want to put a delay of 5 minutes, have you looked at the Linux "sleep" command or using python's "time.sleep"? In this way you can keep a terminal open and just have the job run in intervals.

To keep it simple:

#!/usr/bin/env python3
import time

def foo():
    a = input()
    print("Hello, {}".format(a))

if __name__ == '__main__':
    while True:
        foo()
        time.sleep(300) # Sleeps 300 seconds

Answer 4

You can get a script and use that in the crontab:

#!/bin/bash
/usr/bin/python3 /home/user/project/test.py << EOF
some input here
EOF

Your crontab will look like

* *  * * *   /home/user/project/test.sh >>  /home/user/project/LOG 2>&1