将$ PWD与subprocess.Popen（）结合使用会导致Docker错误，可从shell运行

Question

I want to run a docker command from python using the subprocess Popen:

proc = subprocess.Popen(
    shlex.split(r'docker run -v $PWD:/data blang/latex pdflatex main.tex'),
    cwd=temp_dir, shell=False, stdout=subprocess.PIPE, 
stdin=subprocess.PIPE, stderr=subprocess.PIPE)
proc.communicate()

While the command from the terminal works perfect, this returns:

(b'', b'docker: Error response from daemon: create $PWD: "$PWD" includes invalid characters for a local volume name, only "[a-zA-Z0-9][a-zA-Z0-9_.-]" are allowed.\\nSee \\'docker run --help\\'.\\n')

Answer 1

"$PWD" is a shell expansion. If you don't have a shell (as with shell=False ), it doesn't get expanded.

'%s:/data' % os.getcwd() is a Python expression which will have the same result as "$PWD:/data" in shell. Thus:

import os, subprocess
proc = subprocess.Popen(
    ['docker', 'run',
     '-v', '%s:/data' % os.getcwd(),
     'blang/latex', 'pdflatex', 'main.tex'],
    cwd=temp_dir, shell=False, stdout=subprocess.PIPE, 
    stdin=subprocess.PIPE, stderr=subprocess.PIPE)

It's important not to use shlex.split() in this case: If you did, and were in a directory with spaces in its name, each segment of that directory would become a separate argument.