Python applications can be distributed in various forms depending on the target audience's technical expertise.

The most common distribution methods include:

• .py files: Suitable for open-source projects where source code visibility is acceptable. Users must have Python installed along with required libraries.
• .pyc files: Used when source code protection is necessary. These are compiled bytecode files that are platform-independent but still require a compatible Python runtime.
• Executable binaries: Ideal for end-users who may not be familiar with Python environments. These packages simplify installation and execution but require platform-specific builds.

Packaging Python scripts into executables can be achieved using tools like PyInstaller.

Installing PyInstaller

To install PyInstaller via pip:

pip install pyinstaller

For manual installation from source:

python setup.py install

Confirm successful installation:

pyinstaller --version

Basic Usage of PyInstaller

The basic command syntax is:

pyinstaller [options] script [script...]

To create an executable from myscript.py:

pyinstaller myscript.py

This generates two directories: build and dist. The dist folder contains the executable and associated dependencies. For cleaner distribution, use the single-file mode:

pyinstaller -F myscript.py

In this case, only one executable file is produced in the dist directory.

When dealing with configuration files that need to remain accessible, ensure all paths within the script are absolute. Otherwise, the executable will fail to locate these resources at runtime.

Advanced Options

PyInstaller also provides several utility commands:

• pyi-archive_viewer: Inspect contents of packaged archives.
• pyi-bindepend: Analyze dynamic libray dependencies.

A .spec file is automatically generated during packaging. It defines how PyInstaller processes the application and can be manually edited for advenced customization.

To generate a spec file:

pyi-makespec options script [script...]

Then build using:

pyinstaller specfile

Or:

pyi-build specfile

How PyInstaller Works

PyInstaller bundles the Python interpreter together with your application code into a single executable. This process does not compile Python code into native machine code; thus, performance improvements are not expected. Instead, it simplifies deployment by eliminating the need for users to install Python or its dependencies.

On Unix-like systems, it relies on tools such as ldd and objdump to resolve dependencies.

Common Packaging Challenges

Hiding Console Window

To prevent a console window from appearing when running the executable:

1. If using a .spec file, set console=False.
2. Alternatively, pass the --noconsole flag:

pyinstaller --noconsole myscript.py

For a single-file executable:

pyinstaller -F --noconsole myscript.py

Custom Output Directory

Use the -p option to specify additional paths for module loading and -i for custom icons:

pyinstaller -F -w -p D:\tmp\core-python\libs -i D:\tmp\main.ico main.py

Options:

• -F: Create a single executable file.
• -D or --onedir: Generate a directory containing the executable and dependencies (default).
• -w or --windowed: Hide console window (useful for GUI apps).
• -c or --console: Show console window (default behavior).
• -p: Add directories to Python path.
• -i: Set icon for the executable.