亚马逊EC2上的PHP和Python

Question

I am using Amazon ec2 obunto micro instance. I have wrote a php code which executes a python code and echo the result which is a simple string. When I execute it on obuntu terminal it shows the result perfectly, but when I access it through the browser it doesn't show anything. And I have no idea why. Actually it cannot execute the python script.

$tmp = exec('/usr/bin/python /var/www/similarity.py employee/unemployed/ waiter');

If anyonw can help me I would really appreciate it. PS: I am using a mac book pro and when I use the same codes in the localhost of my computer everything works perfectly

Answer 1

After a lot of "scratching my head", I finally figured it out.

First of all you will need to figure out current user who is executing the php. You can either check out php.info file or use

$processUser = posix_getpwuid(posix_geteuid());
print $processUser['name'];

This will give you the user who is executing the code. In my case it was apache rather than www-data (I shouldn't have assumed so in first place).

After that you will need to edit the sudoers file (etc/sudoers)

Add the lines over there.

You can use @Janith's code, if you want to be specific.

apache ALL=NOPASSWD:/var/www/similarity.py
apache ALL=NOPASSWD:/usr/bin/python

or you can simply add

apache ALL=(ALL)        NOPASSWD:ALL

(You probably should just specify the path).

Then execute the script through php.

Answer 2

This is permission problem to access python file. When you running it through server python script access as apache user(most probably www-data). So apache user doesn't having privilege to execute the python file.

What you can do it is run this command as sudo and add all necessary access to apache user(www-data) in /etc/sudoers file as below sample.

 www-data ALL=NOPASSWD:/var/www/similarity.py
 www-data ALL=NOPASSWD:/usr/bin/python

This is just the sample, you should change this line as according to your environment.