README.md

pox

utilities for filesystem exploration and automated builds

About Pox

pox provides a collection of utilities for navigating and manipulating filesystems. This module is designed to facilitate some of the low level operating system interactions that are useful when exploring a filesystem on a remote host, where queries such as "what is the root of the filesystem?", "what is the user's name?", and "what login shell is preferred?" become essential in allowing a remote user to function as if they were logged in locally. While pox is in the same vein of both the os and shutil builtin modules, the majority of its functionality is unique and compliments these two modules.

pox provides Python equivalents of several unix shell commands such as which and find. These commands allow automated discovery of what has been installed on an operating system, and where the essential tools are located. This capability is useful not only for exploring remote hosts, but also locally as a helper utility for automated build and installation.

Several high-level operations on files and filesystems are also provided. Examples of which are: finding the location of an installed Python package, determining if and where the source code resides on the filesystem, and determining what version the installed package is.

pox also provides utilities to enable the abstraction of commands sent to a remote filesystem. In conjunction with a registry of environment variables and installed utilites, pox enables the user to interact with a remote filesystem as if they were logged in locally.

pox is part of pathos, a Python framework for heterogeneous computing. pox is in active development, so any user feedback, bug reports, comments, or suggestions are highly appreciated. A list of issues is located at https://github.com/uqfoundation/pox/issues, with a legacy list maintained at https://uqfoundation.github.io/project/pathos/query.

Major Features

pox provides utilities for discovering the user's environment:

• return the user's name, current shell, and path to user's home directory
• strip duplicate entries from the user's $PATH
• lookup and expand environment variables from ${VAR} to value

pox also provides utilities for filesystem exploration and manipulation:

• discover the path to a file, exectuable, directory, or symbolic link
• discover the path to an installed package
• parse operating system commands for remote shell invocation
• convert text files to platform-specific formatting

Current Release

The latest released version of pox is available from: https://pypi.org/project/pox

pox is distributed under a 3-clause BSD license.

Development Version

You can get the latest development version with all the shiny new features at: https://github.com/uqfoundation

If you have a new contribution, please submit a pull request.

Installation

pox can be installed with pip::

$ pip install pox

Requirements

pox requires:

• python (or pypy), >=3.8
• setuptools, >=42

Basic Usage

pox includes some basic utilities to connect to and automate exploration on local and remote filesystems. There are some basic functions to discover important locations::

>>> import pox
>>> pox.homedir()
'/Users/mmckerns'
>>> pox.rootdir()
'/'

or, you can interact with local and global environment variables::

>>> local = {'DEV':'${HOME}/dev', 'FOO_VERSION':'0.1', 'BAR_VERSION':'1.0'}
>>> pox.getvars('${DEV}/lib/foo-${FOO_VERSION}', local)
{'DEV': '${HOME}/dev', 'FOO_VERSION': '0.1'}
>>> pox.expandvars('${DEV}/lib/foo-${FOO_VERSION}', local)
'${HOME}/dev/lib/foo-0.1'
>>> pox.expandvars('${HOME}/dev/lib/foo-0.1')
'/Users/mmckerns/dev/lib/foo-0.1'
>>> pox.env('HOME')
{'HOME': '/Users/mmckerns'}

and perform some basic search functions::

>>> pox.find('python3.9', recurse=5, root='/opt')
['/opt/local/bin/python3.9']
>>> pox.which('python3.9')
'/opt/local/bin/python3.9'

pox also has a specialized which command just for Python::

>>> pox.which_python()
'/opt/local/bin/python3.9'
>>> pox.which_python(lazy=True, version=True)
'`which python3.9`'

Any of the pox functions can be launched from the command line, which facilitates executing commands across parallel and distributed pipes (such as pathos.connection.Pipe and pathos.secure.connection.Pipe)::

>>> import pathos
>>> p = pathos.connection.Pipe()
>>> p(command="python -m pox 'which_python()'")
>>> p.launch()
>>> print(p.response())
'/usr/bin/python'
>>> p.kill()

The functions in pox that help make interactions with filesystems and environment varialbles programmatic and abstract become especially relevant when trying to execute complex commands remotely.

More Information

Probably the best way to get started is to look at the documentation at http://pox.rtfd.io. Also see pox.tests for a set of scripts that demonstrate how pox can be used to interact with the operating system. You can run the test suite with python -m pox.tests. All pox utilities can be launched directly from an operating system terminal, using the pox script (or with python -m pox). The source code is also generally well documented, so further questions may be resolved by inspecting the code itself. Please feel free to submit a ticket on github, or ask a question on stackoverflow (@Mike McKerns). If you would like to share how you use pox in your work, please send an email (to mmckerns at uqfoundation dot org).

Citation

If you use pox to do research that leads to publication, we ask that you acknowledge use of pox by citing the following in your publication::

M.M. McKerns, L. Strand, T. Sullivan, A. Fang, M.A.G. Aivazis,
"Building a framework for predictive science", Proceedings of
the 10th Python in Science Conference, 2011;
http://arxiv.org/pdf/1202.1056

Michael McKerns and Michael Aivazis,
"pathos: a framework for heterogeneous computing", 2010- ;
https://uqfoundation.github.io/project/pathos

Please see https://uqfoundation.github.io/project/pathos or http://arxiv.org/pdf/1202.1056 for further information.