与直接执行时不同的运行bash脚本（运行python脚本）的Cron作业

Question

I have a python script that creates a csv and saves it to:

file = example.csv
fileDone = os.path.abspath('/home/bw/temp/%s'%file1)

with open(fileDone, 'w+') as myFile:
    a = csv.writer(myFile, delimiter=',')
    a.writerow(['login report for %s from %s to %s:\n\n'%(name[0],start_date,end_date)])
    dato = ['Username','Logins','Platform']
    a.writerow(dato)
    for vizL in vizList:
        data =[str(vizL[0]),str(vizL[1]),"Viz"]
        a.writerow(data)
    for appL in appList:
        data =[str(appL[0]),str(appL[1]),"Analytics"]
        a.writerow(data)

then a bash script calls the python script:

#!/bin/bash

python scriptname.py

REPORT_MONTH=`/bin/date "+%d %B %Y"`

echo -e "Attached is the login reports for $REPORT_MONTH\n\n\n\n\n\nGenerated by: $0" | mutt -a /home/bw/temp/example.csv -c my@email.com -s "Daily Login Reports For $REPORT_MONTH"

Then cron runs the bash script daily.

When I run the bash script manually, everything works fine and the dates are correct. But when its run by cron, it doesn't seem to overwrite the csv file and just sends one that was already in the /temp folder. So I assume it is not regenerating the csv hence not running the python script.

This is my first time setting up a cron job to run a bash script that runs a python script. Any potential insight as to why this is happening would be greatly appreciated.

Answer 1

There are two things that I would try:

First, try setting the full path to the python script in the bash script, something like this:

#!/bin/bash
python /home/user/scripts/scriptname.py
REPORT_MONTH=`/bin/date "+%d %B %Y"`
echo -e "Attached is the login reports for $REPORT_MONTH\n\n\n\n\n\nGenerated by: $0" | mutt -a /home/bw/temp/example.csv -c my@email.com -s "Daily Login Reports For $REPORT_MONTH"

Second, if the previous didn't work, it might be a problem with the cron job not having permissions to overwrite the file. Which user is the cron running under? (it's usually root). Can you post the output of crontab -l ? If you remove the file and let the cron create it, does it gets created?

Answer 2

First I would make sure your cron is using bash; by default it uses sh. You can include SHELL=/bin/bash to change it.