Python Reading KM Variable in PyCharm Encounters Error

[martin]

Hi,
When I try to read a KM variable into Python, I'm encountering an error.

A simple code:

#!/usr/bin/python3
import os
v = os.environ['KMVAR_Var']
print(v)

Error:

Traceback (most recent call last):
File "/Users/UserName/PycharmProjects/practice/tempUse.py", line 3, in
v = os.environ['KMVAR_Var']
File "/usr/local/Cellar/python@3.9/3.9.5/Frameworks/Python.framework/Versions/3.9/lib/python3.9/os.py", line 679, in getitem
raise KeyError(key) from None
KeyError: 'KMVAR_Var'

I searched elsewhere and have not been able to find a solution.
Can anyone help?

If I execute the python file in KM. It runs successfully. So the problem is probably with PyCharm.

Thanks!

[tiffle]

While you are correctly getting the KM variable from the environment, the environment has to be the KM one - not any other shell which is why your script works when called from within KM. The variable simply does not exist outside KM.

[martin]

@tiffle

While you are correctly getting the KM variable from the environment, the environment has to be the KM one - not any other shell which is why your script works when called from within KM. The variable simply does not exist outside KM.

Thanks, @tiffle. That's very helpful!
Does this mean I will never be able to read KM variables if the python is not executed by Keyboard Maestro? Or is there a way to do that? KM is not a good place to debug my code. I'd like to write and test the code in PyCharm and then hand it over to KM.

[tiffle]

As @ccstone put it:

"You cannot access Keyboard Maestro shell variables outside of its Execute a Shell Script actions, because the variables are exported to the action at runtime."

in this thread:

How Python script is invoked determines value of $KMVAR_ Why?

Hey @sims, Either JXA or AppleScript is the way to go. You cannot access Keyboard Maestro shell variables outside of its Execute a Shell Script actions, because the variables are exported to the action at runtime. You could use a script file – edit that file from VSC – and run it from Keyboard Maestro, but that's not the same as what you're requesting. -Chris

[tiffle]

@martin

KM is not a good place to debug my code. I'd like to write and test the code in PyCharm and then hand it over to KM

What I've done when debugging AppleScript in Script Debugger is to replace those bits of code that access KM variables with simple variable assignments, so the code gets the variable values from the assignments rather than trying to access the KM environment. Then, when debugging is over (if it ever is!) I comment out those assignments and reinstate the code that accesses KM. You could do the same in Python.

It's a lot easier to do than describe but as a workaround it's OK.

[martin]

@tiffle

As @ccstone put it:

"You cannot access Keyboard Maestro shell variables outside of its Execute a Shell Script actions, because the variables are exported to the action at runtime."

Thanks! That's very helpful! I've also learned from there that running AppleScript in Python can get the variables.

@tiffle

What I've done when debugging AppleScript in Script Debugger is to replace those bits of code that access KM variables with simple variable assignments, so the code gets the variable values from the assignments rather than trying to access the KM environment. Then, when debugging is over (if it ever is!) I comment out those assignments and reinstate the code that accesses KM. You could do the same in Python.

Thanks! Now I've understood the issue. I probably will do the same.

[tiffle]

@martin

I've also learned from there that running AppleScript in Python can get the variables.

I missed that - it's a pretty clever way to do it!