Overpackaged

Overview

This project serves as a demonstration of various methods of packaging a standalone Python application in a truly (i hope) portable way.

About the Experimental Application

The experimental application, named myapp, is written in Python and depends on:

• pycurl
• click
• psycopg2
• and C extension called myextension

myapp also includes a myapp run command which verifies that the dependencies are working correctly.

Detailed Explanation

psycopg2 and pycurl were deliberately chosen because they have system dependencies and C extensions, yet do not come with pre-built binary wheels. Therefore, they will be compiled on dev machine, which could lead to portability issues. These issues arise not just from system dependencies but also if your system has a newer version of glibc than the one that is broadly compatible.

The build scripts in the Overpackaged project address these problems by repacking (fixing) each dependency and myapp itself into a manylinux compliant wheel with auditwheel tool. This process ensures that the resulting wheels are portable across various Linux distributions that support the manylinux standard.

Moreover, the build process using tools like PyOxidizer and Nuitka takes place in a controlled environment, ensuring the generation of portable build artifacts. This method maintains consistency across different build environments and systems.

Build artifacts

After the build myapp will be available as five different types of executables:

• myapp.AppImage – An AppImage containing both Python and myapp, allowing it to run on many Linux systems without installation.
• myapp_nuitka_onefile – A standalone executable compiled with Nuitka. It includes all necessary shared libraries within a single file.
• myapp_nuitka_as_folder/myapp – Similar to the one-file version, but with shared libraries placed in the same directory rather than compiled into the binary.
• pyoxidizer/myapp – A binary produced by PyOxidizer that packaging Python and myapp into a single executable, which extracts itself at runtime.
• myapp.pex – An executable created with PEX that does not include Python and requires a separate Python environment to run.

Prerequisites

To build and test this project, you will need:

• docker
• make
• hyperfine (needed only for benchmarking)

Building the Project

To build the whole project, run the following command:

make pyoxidizer nuitka pex appimage

Or to build only one of the executables:

make pyoxidizer
make nuitka
make pex
make appimage

Benchmarking

To benchmark the performance of the packaged applications, use the following command:

make benchmark

This command will run pyoxidizer, appimage and two nuitka executables and compare two metrics among them - the startup time and full time

Output should look close to this:

Benchmarking startup time...

Summary
  pyoxidizer/myapp --help ran
    3.21 ± 0.26 times faster than myapp_nuitka_as_folder/myapp --help
    5.72 ± 0.71 times faster than myapp_nuitka_onefile --help
    7.04 ± 1.53 times faster than myapp.AppImage --help


Benchmarking full working time...

Summary
  pyoxidizer/myapp run ran
    1.58 ± 0.30 times faster than myapp_nuitka_as_folder/myapp run
    2.28 ± 0.42 times faster than myapp_nuitka_onefile run
    2.79 ± 0.54 times faster than myapp.AppImage run

Portability Testing

To test the portability of the packaged applications across different Linux distributions, use:

make portability-test

This command will run pyoxidizer, and nuitka made executables in following linux systems:

• ubuntu:17.04
• ubuntu:18.04
• ubuntu:20.04
• opensuse/leap:15.0
• debian:9
• debian:10

Output should look close to this:

Testing myapp_nuitka_onefile on ubuntu:17.04...
Success: myapp_nuitka_onefile passed on ubuntu:17.04
Testing pyoxidizer/myapp on ubuntu:17.04...
Success: pyoxidizer/myapp passed on ubuntu:17.04
... truncated ...
Success: pyoxidizer/myapp passed on debian:9
Testing myapp_nuitka_as_folder/myapp on debian:10...
Success: myapp_nuitka_as_folder/myapp passed on debian:10
Testing pyoxidizer/myapp on debian:10...
Success: pyoxidizer/myapp passed on debian:10
Total tests run: 18
Successes: 18
Failures: 0