Ubuntu cron shebang not working

Question

I have a script with this as the shebang #!/usr/bin/env node .

When cron runs my script, I get this error /usr/bin/env: node: No such file or directory .

When i run the script as my user the script runs fine, just not as cron. I'm guessing it's because node is not on the PATH of the user that runs cron?

How can I get this shebang to work with cron?

$ which node gives me /home/myuser/.nvm/v0.11.14/bin/node

Answer 1

Cron jobs run in a restricted environment. In an interactive shell, your $PATH is probably set in your $HOME/.bash_profile or $HOME/.bashrc . Cron jobs are executed in an environment that hasn't sourced those files, so your user-specific $PATH settings will not be available.

You can see what that environment looks like by temporarily creating a crontab entry like:

* * * * * printenv > crontab-environment

You can explicitly set $PATH in your crontab, either in the command itself:

* * * * * PATH=$PATH:/home/myuser/.nvm/v0.11.14/bin some_command

or in a separate line in your crontab:

PATH = /usr/bin:/bin:/home/myuser/.nvm/v0.11.14/bin

You can't (directly) use the usual PATH=$PATH:/new/dir syntax to append a directory to your $PATH in an environment setting line, because variable references are not replaced in such a line. They are processed in crontab command lines.

man 5 crontab for details.

Another option is to use an explicit full path in the script itself, changing

#!/usr/bin/env node

to

#!/home/myuser/.nvm/v0.11.14/bin/node

You'll need to customize this for each system where node is installed in a different place. Or you can arrange for node (or nodejs ?) to be installed in a consistent place.