运行 Shell 脚本的 Cron 作业运行 Python 不工作

Question

As written in the title, I am having some problem with my cron job script not executing. I am using CentOS 7.

My crontab -e looks like this:

30 0 * * * /opt/abc/efg/cron_jobs.sh >> /opt/abc/logs/cron_jobs.log

My cron_jobs.sh looks like this:

#!/bin/bash

#keep this script in efg folder
#run this daily through crontab -e
#45 0 * * * /opt/abc/efg/cron_job.sh

cd "$(dirname "$0")"
export PYTHONPATH=$PYTHONPATH:`pwd`

#some daily jobs script for abc
date

#send email to users whose keys will expire 7 days later
/usr/local/bin/python2.7 scripts/send_expiration_reminder.py -d 7
#send email to key owners whos keys will expire
/usr/local/bin/python2.7 scripts/send_expiration_reminder.py -d -1

# review user follow status daily task
# Need to use venv due to some library dependencies
/opt/abc/virtualenv/bin/python2.7 scripts/review_user_status.py

So, what I've found is that the log for the cron jobs in /var/logs/cron states that the cron ran at 0:30 am accordingly.

Strangely, I find that /opt/abc/logs/cron_jobs.log empty, and the scripts does not seem to run at all. It used to output some log before I re-inputted the crontab (to re-install the cron jobs), and replaced cron_jobs.sh, so I think the problem might have arose from those actions.

And also, I would like to know if there are any ways to log the error from executing a python script. I have been trying to run /opt/abc/virtualenv/bin/python2.7 scripts/review_user_status.py but it never seem to work as intended (does not run the main function at all), and there is no log output whatsoever.

I tried to run this on a different machine and it works properly, so I am not sure what is wrong with the cron job.

Here is a snippet of the log I got from /var/log/cron to show that the cron called the job:

Mar 22 18:32:01 web41 CROND[20252]: (root) CMD (/opt/abc/efg/cron_jobs.sh >> /opt/abc/logs/cron_jobs.log)

Answer 1

There are a few areas to check if you haven't performed these already,

1. if your executable permissions set on the script, chmod +x <python file> in addition permissions for the user to access the directories.

2. Run the script manually to test the script works from beginning to end, as the user who will be running the script, will be more realistic.

3. You can test your crontab schedule by temporarily setting every minute for testing, unlike Windows where you can right, click and click Run.

Answer 2

First, thank you all for the suggestions and heads up. I found out that what was ruining my script is the existence of /r in the line break. Apparently, Linux in general does not accept /r and only accepts /n .

It is because I ftp my files to the machine where the script breaks. On the other hand, it works fine on another machine because I used git pull instead of ftp.

Hope that this info will also be a helpful to others!