使用自定义sys.path调用python脚本

Question

Sometimes I need to add custom paths to my python scripts to find certain modules, with sys.path.append("/some/directory/") at the beginning. However, I have a bunch of files that need to use this custom path and I'd like to avoid writing this in every file. I have a main python script that automatically runs all these files using subprocess.call("python", "my_script.py") . How could I achieve the equivalent of sys.path.append("/some/directory/") on every file, from the main script?

Answer 1

If you add the directory to the environment variable PYTHONPATH before invoking subprocess.call() you can achieve the same result as adding the directory via sys.path.append() for a local call. Something like:

import os
p = os.environ.get('PYTHONPATH', script_directory_to_add).split(os.pathsep)
if script_directory_to_add not in p:
    p.append(script_directory_to_add)
os.environ['PYTHONPATH'] = os.pathsep.join(p)