在子进程中创建 pipenv答案

【问题标题】：Creating pipenv in subprocess在子进程中创建 pipenv
【发布时间】：2021-01-23 00:14:25
【问题描述】：

我正在尝试使用 subprocess 在 python 中打开 pipenv virtualenv。我知道我在正确的目录中，但 pipenv 一直在父目录中打开。每次我都通过 rm -r $home/.local/share/virtualenvs/.... 物理删除了父 virtualenv。我确认它们已被删除。这是我正在使用的代码：

import os
import subprocess

def test():
    os.chdir('/home/.../example')
    subprocess.run('ls')
    # works correctly, in proper directory
    subprocess.run('pipenv install django')
    # doesn't work correctly as it installs in parent directory

我该如何解决这个问题？

【问题讨论】：

标签： python subprocess virtualenv pipenv python-os

【解决方案1】：

subprocess.run 基于subprocess.Popen，并将其大部分参数传递给它。现在运行help(subprocess.Popen)时：

class Popen(builtins.object)
 |  Popen(args, [...] cwd=None [...])
                      ^^^^^^^^

您可以设置工作目录。

此外，您应该使用列表来传递要执行的命令。即：

subprocess.run(['pipenv', 'install', django'])

这减少了错误。您可以使用shlex.split 自动完成。

Help on function run in module subprocess:

run(*popenargs, input=None, capture_output=False, timeout=None, check=False, **kwargs)
    Run command with arguments and return a CompletedProcess instance.
    
    The returned instance will have attributes args, returncode, stdout and
    stderr. By default, stdout and stderr are not captured, and those attributes
    will be None. Pass stdout=PIPE and/or stderr=PIPE in order to capture them.
    
    If check is True and the exit code was non-zero, it raises a
    CalledProcessError. The CalledProcessError object will have the return code
    in the returncode attribute, and output & stderr attributes if those streams
    were captured.
    
    If timeout is given, and the process takes too long, a TimeoutExpired
    exception will be raised.
    
    There is an optional argument "input", allowing you to
    pass bytes or a string to the subprocess's stdin.  If you use this argument
    you may not also use the Popen constructor's "stdin" argument, as
    it will be used internally.
    
    By default, all communication is in bytes, and therefore any "input" should
    be bytes, and the stdout and stderr will be bytes. If in text mode, any
    "input" should be a string, and stdout and stderr will be strings decoded
    according to locale encoding, or by "encoding" if set. Text mode is
    triggered by setting any of text, encoding, errors or universal_newlines.
    
    The other arguments are the same as for the Popen constructor.
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

【讨论】：