I am writting a Python script and I am running out of time. I need to do some things that I know pretty well in bash, so I just wonder how can I embed some bash lines into a Python script.
Thanks
The ideal way to do it:
def run_script(script, stdin=None):
"""Returns (stdout, stderr), raises error on non-zero return code"""
import subprocess
# Note: by using a list here (['bash', ...]) you avoid quoting issues, as the
# arguments are passed in exactly this order (spaces, quotes, and newlines won't
# cause problems):
proc = subprocess.Popen(['bash', '-c', script],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
stdin=subprocess.PIPE)
stdout, stderr = proc.communicate()
if proc.returncode:
raise ScriptException(proc.returncode, stdout, stderr, script)
return stdout, stderr
class ScriptException(Exception):
def __init__(self, returncode, stdout, stderr, script):
self.returncode = returncode
self.stdout = stdout
self.stderr = stderr
Exception.__init__('Error in script')
You might also add a nice __str__
method to ScriptException
(you are sure to need it to debug your scripts) -- but I leave that to the reader.
If you don't use stdout=subprocess.PIPE
etc then the script will be attached directly to the console. This is really handy if you have, for instance, a password prompt from ssh. So you might want to add flags to control whether you want to capture stdout, stderr, and stdin.