EasyProcess 0.2.5

Easy to use python subprocess interface.

EasyProcess is an easy to use python subprocess interface.

Links:
* home: https://github.com/ponty/EasyProcess
* documentation: http://EasyProcess.readthedocs.org
* PYPI: https://pypi.python.org/pypi/EasyProcess

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Features:
- layer on top of subprocess_ module
- easy to start, stop programs
- easy to get standard output/error, return code of programs
- command can be list (preferred) or string (command string is converted to list using shlex.split)
- logging
- timeout
- unit-tests
- cross-platform, development on linux
- shell is not supported
- pipes are not supported
- stdout/stderr is set only after the subprocess has finished
- stop() does not kill whole subprocess tree
- unicode support
- supported python versions: 2.7, 3.4, 3.5, 3.6, 3.7
- Method chaining_

Similar projects:
* execute (http://pypi.python.org/pypi/execute)
* commandwrapper (http://pypi.python.org/pypi/commandwrapper)
* extcmd (http://pypi.python.org/pypi/extcmd)
* sh (https://github.com/amoffat/sh)
* envoy (https://github.com/kennethreitz/envoy)
* plumbum (https://github.com/tomerfiliba/plumbum)

Basic usage
===========

>>> from easyprocess import EasyProcess
>>> EasyProcess('python --version').call().stderr
u'Python 2.6.6'

Installation
============

install::

pip install EasyProcess


uninstall::

pip uninstall EasyProcess


Usage
=====

Simple example
--------------

Example program::

#-- include('examples/hello.py')--#
from easyprocess import EasyProcess
import sys

s = EasyProcess([sys.executable, '-c', 'print "hello"']).call().stdout
print(s)
#-#

Output::

#-- sh('python -m easyprocess.examples.hello')--#
hello
#-#


General
-------

The command can be a string list or a concatenated string::

#-- include('examples/cmd.py')--#
from easyprocess import EasyProcess

print('-- Run program, wait for it to complete, get stdout (command is string):')
s=EasyProcess('python -c "print 3"').call().stdout
print(s)

print('-- Run program, wait for it to complete, get stdout (command is list):')
s=EasyProcess(['python','-c','print 3']).call().stdout
print(s)

print('-- Run program, wait for it to complete, get stderr:')
s=EasyProcess('python --version').call().stderr
print(s)

print('-- Run program, wait for it to complete, get return code:')
s=EasyProcess('python --version').call().return_code
print(s)

print('-- Run program, wait 1 second, stop it, get stdout:')
s=EasyProcess('ping localhost').start().sleep(1).stop().stdout
print(s)

#-#

Output::

#-- sh('python -m easyprocess.examples.cmd')--#
-- Run program, wait for it to complete, get stdout (command is string):
3
-- Run program, wait for it to complete, get stdout (command is list):
3
-- Run program, wait for it to complete, get stderr:
Python 2.7.6
-- Run program, wait for it to complete, get return code:
0
-- Run program, wait 1 second, stop it, get stdout:
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.017 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.034 ms
#-#

Shell commands
--------------

Shell commands are not supported.

.. warning::

``echo`` is a shell command on Windows (there is no echo.exe),
but it is a program on Linux

return_code
-----------

:attr:`EasyProcess.return_code` is None until
:func:`EasyProcess.stop` or :func:`EasyProcess.wait`
is called.

With
----

By using :keyword:`with` statement the process is started
and stopped automatically::

from easyprocess import EasyProcess
with EasyProcess('ping 127.0.0.1') as proc: # start()
# communicate with proc
pass
# stopped

Equivalent with::

from easyprocess import EasyProcess
proc = EasyProcess('ping 127.0.0.1').start()
try:
# communicate with proc
pass
finally:
proc.stop()


Timeout
-------

This was implemented with "daemon thread".

"The entire Python program exits when only daemon threads are left."
http://docs.python.org/library/threading.html::

#-- include('examples/timeout.py')--#
from easyprocess import EasyProcess

s = EasyProcess('ping localhost').call(timeout=2).stdout
print(s)
#-#

Output::

#-- sh('python -m easyprocess.examples.timeout')--#
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.018 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.037 ms
64 bytes from localhost (127.0.0.1): icmp_seq=3 ttl=64 time=0.025 ms
#-#


Replacing existing functions
----------------------------

Replacing os.system::

retcode = os.system("ls -l")
==>
p = EasyProcess("ls -l").call()
retcode = p.return_code
print p.stdout

Replacing subprocess.call::

retcode = subprocess.call(["ls", "-l"])
==>
p = EasyProcess(["ls", "-l"]).call()
retcode = p.return_code
print p.stdout


.. _subprocess: http://docs.python.org/library/subprocess.html
.. _chaining: https://en.wikipedia.org/wiki/Method_chaining#Python

.. |Travis| image:: http://img.shields.io/travis/ponty/EasyProcess.svg
:target: https://travis-ci.org/ponty/EasyProcess/
.. |Coveralls| image:: http://img.shields.io/coveralls/ponty/EasyProcess/master.svg
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.. |Latest Version| image:: https://img.shields.io/pypi/v/EasyProcess.svg
:target: https://pypi.python.org/pypi/EasyProcess/
.. |Supported Python versions| image:: https://img.shields.io/pypi/pyversions/EasyProcess.svg
:target: https://pypi.python.org/pypi/EasyProcess/
.. |License| image:: https://img.shields.io/pypi/l/EasyProcess.svg
:target: https://pypi.python.org/pypi/EasyProcess/
.. |Code Health| image:: https://landscape.io/github/ponty/EasyProcess/master/landscape.svg?style=flat
:target: https://landscape.io/github/ponty/EasyProcess/master
.. |Documentation| image:: https://readthedocs.org/projects/pyscreenshot/badge/?version=latest
:target: http://easyprocess.readthedocs.org