Can a python script execute a function inside a bash script?

Question

I have a bash script provided by a 3rd party which defines a set of functions. Here\'s a template of what that looks like

$ cat test.sh

#!/bin/bash

define         


        

Answer 1

No, the function is only available within that bash script.

What you could do is adapt the bash script by checking for an argument and execute functions if a specific argument is given.

For example

# $1 is the first argument

case $1 in
 "go" )
       go
       ;;
 "otherfunc" )
       otherfunc
       ;;
 * )
       echo "Unknown function"
       ;;
esac 

Then you can call the function like this:

subprocess.call("test.sh otherfunc")

Answer 2

Based on @samplebias solution but with some modification that worked for me,

So I wrapped it into function that loads bash script file, executes bash function and returns output

def run_bash_function(library_path, function_name, params):
    params = shlex.split('"source %s; %s %s"' % (library_path, function_name, params))
    cmdline = ['bash', '-c'] + params
    p = subprocess.Popen(cmdline,
                         stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    stdout, stderr = p.communicate()
    if p.returncode != 0:
        raise RuntimeError("'%s' failed, error code: '%s', stdout: '%s', stderr: '%s'" % (
            ' '.join(cmdline), p.returncode, stdout.rstrip(), stderr.rstrip()))
    return stdout.strip()  # This is the stdout from the shell command

Answer 3

Yes, indirectly. Given this foo.sh:

function go() { 
    echo "hi" 
}

Try this:

>>> subprocess.Popen(['bash', '-c', '. foo.sh; go'])

Output:

hi