Running a Python script from PHP

Question

I'm trying to run a Python script from PHP using the following command:

exec('/usr/bin/python2.7 /srv/http/assets/py/switch.py arg1 arg2');

However, PHP simply doesn't produce any output. Error reporting is set to E_ALL and display_errors is on.

Here's what I've tried:

• I used python2, /usr/bin/python2 and python2.7 instead of /usr/bin/python2.7
• I also used a relative path instead of an absolute path which didn't change anything either.
• I tried using the commands exec, shell_exec, system.

However, if I run

if (exec('echo TEST') == 'TEST')
{
    echo 'exec works!';
}

it works perfectly fine while shutdown now doesn't do anything.

PHP has the permissions to access and execute the file.

EDIT: Thanks to Alejandro, I was able to fix the problem. If you have the same problem, don't forget that your webserver probably/hopefully doesn't run as root. Try logging in as your webserver's user or a user with similar permissions and try to run the commands yourself.

Answer 1

Tested on Ubuntu Server 10.04. I hope it helps you also on Arch Linux.

In PHP use shell_exec function:

Execute command via shell and return the complete output as a string.

It returns the output from the executed command or NULL if an error occurred or the command produces no output.

<?php 

$command = escapeshellcmd('/usr/custom/test.py');
$output = shell_exec($command);
echo $output;

?>

In Python file test.py, verify this text in first line: (see shebang explain):

#!/usr/bin/env python

Also Python file must have correct privileges (execution for user www-data / apache if PHP script runs in browser or curl) and/or must be "executable". Also all commands into .py file must have correct privileges:

Taken from php manual:

Just a quick reminder for those trying to use shell_exec on a unix-type platform and can't seem to get it to work. PHP executes as the web user on the system (generally www for Apache), so you need to make sure that the web user has rights to whatever files or directories that you are trying to use in the shell_exec command. Other wise, it won't appear to be doing anything.

To make executable a file on unix-type platforms:

chmod +x myscript.py