Python Packaging (and why you should care)
==========================================

Code Reuse!
-----------

 * 3rd party libraries
 * your own libraries


Loading Python Modules
----------------------

(The short, short version)

 * cython looks in ${PYTHONHOME} (please don't use!)
 * ... in ${PYTHONPATH}
 * in site-packages loaded from site.py




virtualenv
----------

To use::

  virtualenv ${DIRECTORY}
  . ${DIRECTORY}/bin/activate

May want --system-site-packages

Python Packaging
----------------

 * distutils
 * setuptools


Installing Python Packages
--------------------------

The setuptools way::

  easy_install MyPackage

The pip way::

  pip install MyPackage


PyPI
----

*Where do pip and easy_install get their packages?* The Python Package Index

https://pypi.python.org/

( What is really used behind the scene:
https://pypi.python.org/simple/ )


setup.py
--------

What goes in a setup.py file?

 * no one knows!
 * no one cares!

However, it let's you do packaging so you do care a little...

setup.py boilerplate
--------------------

See http://k0s.org/hg/MakeItSo/file/tip/makeitso/python_package/setup.py

Notable keywords:

 * install_requires : list of dependencies
 * entry_points : console scripts (and whatever else you want)
 * zip_safe=False : probably should be the normal case


Upload Packages to PyPI
-----------------------

Once you have a setup.py, you can distribute to your heart's content::

  python setup.py egg_info -RDb "" sdist register upload develop


setuptools vs. distutils (vs. setuptools2 vs distribute....)
------------------------------------------------------------

Python packaging is a mess.

 * distutils is standard, but it doesn't do anything
 * setuptools (kinda) works, but it does too much
   * dependencies
   * python setup.py develop
 * distribute (etc) fixes, but aren't standard...yet

(Long story)


install vs. develop
-------------------


Making your own PyPI
--------------------

Not a difficult directory structure::

  ${INDEX_BASE}/${PACKAGE}/${PACKAGE}-${VERSION}.tar.gz

We should do this!

Then use::

  pip install -i ${INDEX_BASE} ${PACKAGE}

or::

  pip install -i ${INDEX_BASE} ${PACKAGE}=${VERSION}


utils.py and monoliths
----------------------

Why not just have everything.py and call it a day?

 * intent
 * dependencies