Recipe16.11.Automating the py2exe Compilation of Scripts into Windows Executables

Recipe 16.11. Automating the py2exe Compilation of Scripts into Windows Executables

Credit: Alexander Semenov

Problem

You often use py2exe to build Windows .exe files from Python scripts, but you don't want to bother writing a setup.py build script for each and every such script.

Solution

distutils is a package in the standard Python library, ready to be imported from your Python code. py2exe is a third-party extension to distutils for the specific task of generating Windows executables from Python code: you must download and install py2exe separately, but once installed, it cooperates smoothly with the standard distutils. Thanks to these features, you can easily write Python scripts to automate distutils tasks (including py2exe tasks). For example:

from distutils.core import setup import sys, os, py2exe # the key trick with our arguments and Python's sys.path name = sys.argv[1] sys.argv[1] = 'py2exe' sys.path.append(os.path.dirname(os.path.abspath(name))) setup(name=name[:-3], scripts=[name])

Save this as makexe.py in the Tools\Scripts\ folder of your Python installation. (You should always add this folder to your Windows PATH because it contains many useful tools.) Now, from a Windows command prompt, you're able to cd to a directory where you have placed a script (say C:\MyDir\), and there run, say:

C:\MyDir> makexe.py myscript.py

and (assuming that you have a myscript.py script there, and .py among your Windows executable extensions, with association to the Python interpreter) py2exe prepares all the files you need for distributing your masterpiece (as a Windows executable and supporting DLLs), neatly arranged in folder c:\MyDir\dist\myscript\.

Discussion

The distutils package is part of the Python Standard Library. It helps you prepare your Python modules and extensions for distribution, as well as letting you install such packages as distributed by others. py2exe is a freely downloadable third-party extension that works on top of distutils to help you build a Windows .exe file (and a set of supporting DLL files) from a Python-coded program, so that you can distribute your program in executable form to other Windows PCs that may not have Python installed; see http://starship.python.net/crew/theller/py2exe/, both to download py2exe and for detailed documentation of this useful tool.

Following the details given in the distutils (and py2exe) documentation, the canonical way to use distutils (including py2exe) is to write a script, conventionally always named setup.py, to perform all kinds of distutils tasks on your package. Normally, you write a setup.py for each package you distribute, placing it in the top directory of the package (known as the distribution root in distutils terminology).

However, there is nothing mandatory about the convention of writing a setup.py script per package. distutils and py2exe, after all, are written as modules to be imported from Python. So, you can, if you so choose, use all the power of Python to code scripts that help you perform distutils and py2exe tasks in whatever ways you find most convenient.

This recipe shows how I eliminate the need to write a separate setup.py script for each Python script that I convert to an executable with py2exe, and related issues such as the need to keep such scripts in dedicated "distribution root" directories. I suggest you name this recipe's script makexe.py, but any name will do, as long as you avoid naming it py2exe.py (a natural enough temptation). (Naming it py2exe.py would break the script because the script must import py2exe, and if you named the script py2exe.py it would "import itself" instead!)

Place this script on any directory on your Windows PATH where you normally keep executable Python scripts. I suggest you use the Tools\Scripts folder of the Python distribution, a folder that contains several other useful scripts you'll want to have handy (have a look in that folderit's worth your time). I'm not going to delve into the details of how to set and examine your Windows PATH, open a command prompt, make your Python scripts executable, and so on. Such system administration details differ slightly on each version of Windows, and you'll need to master them for any Windows version on which you want to perform significant programming, anyway.

Once you have implemented this Solution, you'll find that making your Python scripts into Windows executables has become so easy and so fast that soon you'll be distributing your neat and useful programs to friends and acquaintances right and left. You won't need to convince them to install the Python runtime files before they can install and run your programs, either! (Of course, in this way they will end up with what amounts to several copies of the runtime files, if they install several of your compiled programsthere is little you can do about that.)

Recipe16.11.Automating the py2exe Compilation of Scripts into Windows Executables