Source code for bag.command

"""Simplifying usage of the **subprocess** module of the standard library."""

import subprocess
from sys import platform


class CommandError(Exception):  # noqa
    def __init__(self, error_message, code, out=""):  # noqa
        self.error_message = error_message
        self.code = code
        self.out = out

    def __str__(self):
        return self.error_message + " (exit code: {})".format(self.code)


def execute(command, input="", shell=True, encoding="utf-8"):
    p = subprocess.Popen(
        command,
        shell=shell,
        stdin=subprocess.PIPE,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        close_fds=not platform.startswith("win"),
    )
    i, o, e = (p.stdin, p.stdout, p.stderr)
    if input:
        i.write(input)
    i.close()
    return_code = p.wait()
    normal_output = o.read().strip().decode(encoding)
    error_output = e.read().strip().decode(encoding)
    o.close()
    e.close()
    return return_code, normal_output, error_output


def checked_execute(command, input="", shell=True, encoding="utf-8", accept_codes=[0]):
    ret, out, err = execute(command, input=input, shell=shell, encoding=encoding)
    if ret in accept_codes:
        return out
    else:
        raise CommandError(err, ret, out)