shell.py 0.5.2

Execute a shell command

Block until return:

>>> from shell import ex
>>> ex('echo hello shell.py').stdout()
'hello shell.py\n'

Asynchronous execution:

>>> from shell import ex
>>> c = asex('echo hello shell.py')
>>> # do something else
...
>>> c.stdout() # wait until process exit and read stdout
'hello shell.py\n'

Pipe commands

from shell import ex
re = (ex("ifconfig")
      | "grep -A 1 eth0"
      | "grep inet"
      | "awk '{print $2}'"
      | "cut -d: -f 2").stdout()

Or

from shell import pipe_all
pipe_all(["ls -la ~",
          "awk '{print $9}'",
          "grep -E '^\.'",
          "wc -l"]).stdout()

Use string as stdin

>>> from shell import instream
>>> instream("1 2 3").p("awk '{print $1}'").stdout()
'1\n'

This is equivalent to:

>>> from shell import ex
>>> ex("echo 1 2 3").p("awk '{print $1}'").stdout()

IO redirect

Overwrite a file:

>>> from shell import ex
>>> ex('echo yolo').wr('/tmp/out')
>>> ex('echo yolo') > '/tmp/out'

Append to a file:

>>> from shell import ex
>>> ex('echo yolo').ap('/tmp/out')
>>> ex('echo yolo') >> '/tmp/out'

Run commands in parallel

Block until all commands return:

>>> from shell import parallel as par
>>> par.ex_all(['sleep 2', 'sleep 2']) # return in 2s

Asynchronous parallel execution:

>>> from shell import parallel as par
>>> pe = par.asex_all(['sleep 2', 'sleep 2']) # return immediately
>>> # do something else
...
>>> pe.wait()

Set working directory

Set the directory in which the commands are executed:

>>> with shell.cwd('~/server/data/upload/') as old_path:
>>>     shell.ex('find ./images -name "*.png"') | 'minify ./public' >> 'upload.log'

This is equivalent to:

>>> shell.ex('find ~/server/data/upload/images -name "*.png"') | 'minify ~/server/data/upload/public' >> '~/server/data/upload.log'

See test cases for more examples.