Read php var from Python - php

Question

Here is my code, that is supposed to work according to answers to other similar questions, but it does not.
PHP:
<?PHP
$par = $_POST["parameter"];
$importPar=exec("py pyData.py . $par"); //also tried shell_exec()
print ($par);
print($importPar);
?>
Python:
import sys
who = sys.argv[1]
print("This is php var: ",who)
It might have to do something with my cmd because nothing is returned even when I try:
$test=shell_exec('ipconfig');
echo $test;

Answer 1

With minor modifications, your code works just fine on my PHP 5.6.3 setup. The only substantive difference in my example below is that $par gets set locally, and not from a $POST input.
Minor corrections:
1. The . isn't necessary when you're including a $variable inside double quotes. This will actually make python think you want to print . instead of $par, as . is read as sys.argv[1].
2. I'm assuming py is an alias, but I needed to use python in exec() to run properly.
3. You'll get a tuple as print output with your python statement as-is: ('This is php var: ', 'foo')
. Consider using .format() instead, see below.
""" test.py
import sys
who = sys.argv[1]
print('This is php var: {}'.format(who))
"""
<?PHP
$par = "foo";
$importPar=exec("python test.py $par");
print ("$par\n");
print($importPar);
?>
Output:
foo
This is php var: test.py
Process finished with exit code 0