Skip to main content

A shell-like DSL front for subprocess.Popen

Project description

popen

What is it?

The popen package provides a simple shell-like syntax inside python for running external commands.

Features:

  • Chaining (aka. piping) as Sh('ls') | 'sort'

  • Redirect stderr to stdout as Sh('make').include_stderr | 'wc'

  • Redirect output to file as Sh('ls') > '~/listing.txt'

  • Iteration over output lines as for line in Sh('ls'):

  • Streaming input into commands in the chain as Sh('grep', '-q', 'code').stdin('~/listing.txt').returncode

  • Expands special characters (~*!?)

  • Expands env vars ($HOME) as print Sh('ls', '$USER', '~/*')

  • Properly splits strings ('echo "hole in one"' becomes ['echo', 'hole in one'])

  • Or iterable arguments (Sh('ls', '-l') | ['wc', '-l'] > '/dev/null')

TL;DR

Installation:

pip install popen

Example:

from popen import Sh
for line in Sh('du', '~/') | 'head -n 10' | 'sort -n':
    print('GOT', line)

Usage

Simples usage, run a command and iterate the output lines:

from popen import Sh
for line in Sh('ls', '-la', '~'):
    print line

Piping that output to a file:

Sh('ls', '-la', '~') > '~/listing'

Note that special characters like ~ are expanded, as are environment variables (e.g. $HOME).

Chaining commands is trivial, here with append instead of write to file:

Sh('ls') | Sh('sort') >> '~/listing'

But the right hand side of | can be very flexible, as it employs lexical splitter on string input or takes an iterable:

Sh('ls', '-la', '~') | 'sort -c' | ['uniq', '-c'] | 'tail' | Sh('wc') > '~/listing'

To run a command and let output go to stdout, ask for the return code:

cmd = Sh('ls') | 'grep polka'
print cmd.returncode

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

popen-0.1.14.tar.gz (4.9 kB view hashes)

Uploaded Source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page