Abstract command wrapper for Python

command.py

import subprocess


class Command(object):
    def __init__(self, *args, encode='utf8'):
        self.encode = encode
        self.args = args
    
    def __repr__(self):
        return '<Command({})>'.format(' '.join(self.args))

    def __getattr__(self, name):
        args = self.args + (name,)
        return self.__class__(*args)
    
    def __call__(self, *args, **kwargs):
        return self.__run(*args, **kwargs)

    def __run(self, *args, **kwargs):
        cmd = self.__build_cmd(*args, **kwargs)

        process = subprocess.Popen(
            cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            cwd=None
        )
        stdout, stderr = process.communicate()
        stdout = stdout.decode(self.encode)
        stderr = stderr.decode(self.encode)

        if process.returncode != 0:
            raise Exception(cmd, process.returncode, (stdout, stderr))
        else:
            return stdout, stderr
    
    def __build_cmd(self, *args, **kwargs):
        options = []
        for key, value in kwargs.items():
            if value is None:
                options.append('--{}'.format(key))
            else:
                options.append('--{}={}'.format(key, value))

        return self.args + args + tuple(options)


ls = Command('ls')
stdout, stderr = ls('-la')
print(stdout,stderr)