Embed bash in python

Question

I am writting a Python script and I am running out of time. I need to do some things that I know pretty well in bash, so I just wonder how can I embed some bash lines into a

Answer 1

@Ian Bicking's answer is useful but it if only allow us to run scripts. Instead we can come up with a more flexible code where we can run command as well. I have a different approach from his.

#!/usr/bin/env python3

from subprocess import Popen, PIPE


class BashCommandsException(Exception):
    def __init__(self, returncode, output, error_msg):
        self.returncode = returncode
        self.output = output
        self.error_msg = error_msg
        Exception.__init__('Error in executed command')


def popen_communicate(cmd, stdout_file=None):
    """Acts similir to lib.run(cmd) but also returns the output message captures on
    during the run stdout_file is not None in case of nohup process writes its
    results into a file
    """
    cmd = list(map(str, cmd))  # all items should be string
    if stdout_file is None:
        p = Popen(cmd, stdout=PIPE, stderr=PIPE)
    else:
        with open(stdout_file, "w") as outfile:
            # output written into file, error will be returned
            p = Popen(cmd, stdout=outfile, stderr=PIPE, universal_newlines=True)
            output, error = p.communicate()
            p.wait()
            return p, output, error

    output, error = p.communicate()
    output = output.strip().decode("utf-8")
    error = error.decode("utf-8")
    return p, output, error


def run(cmd):
    log_file = "/tmp/log.txt"
    # if log_file is not provided returned output will be stored in output
    p, output, error_msg = popen_communicate(cmd, log_file)
    if p.returncode != 0:
        raise BashCommandsException(p.returncode, output, error_msg, str(cmd))
    return output


if __name__ == "__main__":
    # This could be any command you want to execute as you were in bash
    cmd = ["bash", "script_to_run.sh"]
    try:
        run(cmd)
    except Exception as e:
        print(e)