Automation for python package logic

This a small post presenting how to build a simple executable for your python project.

PS : after stumbling upon this cookicutter repo, I believe this is probably the go-to when you want to build a new python package.

Why do I need that ?

Easy launch of command line jobs

Get your executable, launch your logic with something like my_exec -m my_package --arg1 value1. Job is done.

On top of that, you can store all the previous executables from earlier version of your job and run regressions tests.

What tool to use ?

pex

It offers the packaging feature that we want. At the end of the build, we get a *.pex file that we can later use as myproject.pex -m my_package --arg1 value1.

A boilerplate code

Available here, it gives the basic blocks to build a pex with your python package.

In short, run the following commands to see how your project can be built as an executable

tox
./dist/app.pex -m my_project

pex_build

What this does is :

Build the package requirements in a virtual env
Install your custom package
Create a zip that will be the .pex file
you can launch your __main__.py with the second line of the command line