Standalone Application with Briefcase

Briefcase is a tool for packaging Python projects as standalone native applications. It can produce installers and executables for macOS, Windows, and Linux that do not require the user to install Python or any dependencies.

• Produces platform-native installers (.pkg on macOS, .msi on Windows, .deb/.rpm on Linux).
• Bundles a Python interpreter and all dependencies.
• Supports passing command line arguments to the app.

This page outlines the basics of packaging a Click application with Briefcase. Be sure to read its documentation and use briefcase --help to understand what features are available.

Installation

Install Briefcase in the virtual environment:

pip install briefcase

Configuration

Add a [tool.briefcase] section and a [tool.briefcase.app.<app-name>] section to pyproject.toml. Set console_app = true so Briefcase treats the project as a command line application rather than a GUI application.

Given a Click application with the following project structure:

hello-cli/
    src/
        hello_cli/
            __init__.py
            app.py
    LICENSE
    pyproject.toml

Where app.py contains a Click command:

import click

@click.command()
@click.argument("name", default="World")
@click.option("--count", default=1, help="Number of times to greet.")
def main(name, count):
    """Greet someone by NAME (default: World)."""
    for _ in range(count):
        click.echo(f"Hello, {name}!")

Add the following Briefcase configuration to pyproject.toml:

[tool.briefcase]
project_name = "Hello CLI"
bundle = "com.example"
version = "0.0.1"
url = "https://example.com/hello-cli"
license.file = "LICENSE"
author = "Your Name"
author_email = "[email protected]"

[tool.briefcase.app.hello-cli]
formal_name = "Hello CLI"
description = "My first application"
long_description = """More details about the app should go here.
"""
sources = [
    "src/hello_cli",
]
console_app = true
requires = [
    "click",
]

The key settings are:

• console_app = true -- tells Briefcase this is a terminal application, not a GUI.
• sources -- the list of source packages to include.
• requires -- the Python dependencies to bundle (Click and any other libraries the project needs).

Entry Point

Briefcase launches the application by running the package with python -m <package>, so a __main__.py file must exist in the package. Without it, Briefcase will not be able to start the application.

Create __main__.py in the package directory and call the Click command:

from hello_cli.app import main

if __name__ == "__main__":
    main()

Running

Use briefcase dev to run the application directly from the source tree. Pass command line arguments after --:

$ briefcase dev -- World
Hello, World!
$ briefcase dev -- World --count 2
Hello, World!
Hello, World!

Building and Packaging

To create a distributable executable, run the following commands:

briefcase create
briefcase build
briefcase package

briefcase create downloads a Python interpreter and installs dependencies into an isolated app bundle. briefcase build compiles the app, and briefcase package produces the final platform installer.

On macOS, this produces a .pkg installer. On Windows, it produces a .msi installer. On Linux, it produces a system package (.deb, .rpm, etc.) for the current distribution.

Once installed, users can run the application directly from the terminal:

$ hello-cli World
Hello, World!
$ hello-cli World --count 2
Hello, World!
Hello, World!