Cron job running a Django Python command through a virtual environment not working

Question

I have a crontab file supposedly executing a Django command after loading the project virtual environment:

*/1 * * * * source /home/virtualenvs/mydjangoproject-venv/bin/activate && python /home/www/production/mydjangoproject/manage.py mydjangocommand 

...but it does absolutely nothing. The cron log outputs no particular problem:

Mar 13 19:51:01 110 CRON[23807]: (root) CMD (source /home/virtualenvs/mydjangoproject-venv/bin/activate && python /home/www/production/mydjangoproject/manage.py mydjangocommand) 

Needless to say, the command itself works perfectly when copy-pasted in the shell.

I know it is related to the environment variables of my crontab, but I'm very uneducated regarding this matter, and I have no idea what to do especially when it is run under a python virtual env. Should it use my user environment variables? The ones from the virtualenv? How to implement that? Thanks!

NB: In case it helps, I have the following output of my crontab environment variables (when exporting "env" to a file through the crontab):

HOME=/root LOGNAME=root PATH=/usr/bin:/bin LANG=en_US.UTF-8 SHELL=/bin/sh LC_ALL=en_US.UTF-8 PWD=/root 

And the following environment variables under the project virtual environment:

TERM=xterm-256color SHELL=/bin/bash SSH_CLIENT=x.x.x.x 53007 22 OLDPWD=/root/production/mydjangoproject SSH_TTY=/dev/pts/0 LC_ALL=en_US.UTF-8 USER=root VIRTUAL_ENV=/home/virtualenvs/mydjangoproject-venv MAIL=/var/mail/root PATH=/home/virtualenvs/mydjangoproject- venv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin PWD=/root LANG=en_US.UTF-8 PS1=(mydjangoproject-venv)${debian_chroot:+($debian_chroot)}\u@$(hostname -f):\w\$ SHLVL=1 HOME=/root LS_OPTIONS=--color=auto --group-directories-first LOGNAME=root SSH_CONNECTION=x.x.x.x 53007 x.x.x.x 22 LC_CTYPE=en_US.UT 

Answer 1

There are a couple of ways to solve this:

First, it doesn't work because /bin/sh is the shell cron uses to run commands, but /bin/sh doesn't support source. So the quick fix is to set SHELL=/bin/bash in the crontab.

Or...

Second, it's not necessary to source virtualenv/bin/activate anyway. You can just call the virtualenv python directly.

* * * * * cd /home/www/production/mydjangoproject; /home/virtualenvs/mydjangoproject-venv/bin/python manage.py mydjangocommand 

These were taken from this question on SO, the answers to which may contain other ideas for people in similar but not quite the same circumstances.