Running Python Script with Launchd: imports not found

Question

I've been trying to set up a script to run a python program at regular intervals using launchd. The python program fails because it can't find my imports---I know this because I caught the errors in a log file. To fix this problem, I created ~\.MacOSX\environment.plist, and duplicated my PYTHONPATH there, logged out and logged in again. This seems to be insufficient to solve the problem, and I'm at a loss as to what else to try.

I'm running OSX, 10.8.3.

Related threads:

• launchd executes python script, but import fails (not applicable--my script points to the right python instance)

UPDATE:

It appears that I can run the following command:

launchctl setenv PYTHONPATH $PYTHONPATH

and the script will execute successfully. So, to modify my question:

1. Where does this get stored? I checked ~\.launchd.conf and \etc\.launchd.conf, neither existed.
2. Presumably this setting is dumped when I reboot. Where can I change this information so that launchd will find it?

Answer 1

To set the environment of a specific job you should use the EnvironmentVariables key in the job definition itself:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.example.app</string>
    <key>Program</key>
    <string>/path/to/your/script</string>
    <key>EnvironmentVariables</key>
    <dict>
        <key>PYTHONPATH</key>
        <string>/your/python/path</string>
    </dict>
</dict>
</plist>

You may define default environment variables for launchd(8) services by editing /etc/launchd.conf for daemons or /etc/launchd-user.conf for agents. The latter one works but is not documented. The currently documented (but unsupported) per-user config file is $HOME/.launchd.conf.

These config files contain a list of launchctl(1) subcommands. The one you want is:

setenv PYTHONPATH /your/python/path

Update: /etc/launchd.conf is not supported in Mac OS X 10.10 and higher. On these systems you'll have to define environment variables on a per-job-basis.

Answer 2

None of the above actually worked for me (OS X 10.11.3). The breakthrough was reading this script runs fine in terminal but not from launchd and realizing belatedly that one can write the absolute full path to the version of python with the right modules. D'oh.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.example.app</string>
    <key>ProgramArguments</key>
    <string>/path/to/your/python</string>
    <string>/path/to/your/script</string>
</dict>
</plist>