Execute command using a subprocess and write streaming output to the screen

exec_cmd.py

import logging
import subprocess
from io import BytesIO


def execute_command(cmd, ns=__name__, shell_flag=False):
    """
    Execute command using a subprocess, and write streaming output to the screen.

    :param cmd: Command-line statement
    :param ns: Namespace to be used in logging
    :param shell_flag: Flag to run subprocess in a shell (default: False)
    """
    def report(level, _lines):
        for line in BytesIO(_lines).read().decode('utf-8').split(u'\n'):
            if line != u'':
                getattr(logging.getLogger(ns), level)(line.strip())
                
    logging.getLogger(ns).debug(cmd)
    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=shell_flag)
    stdout, stderr = proc.communicate()
    report('info', stdout)
    report('error', stderr)