Python Fire

Python Fire is a library for creating command line interfaces (CLIs) from absolutely any Python object.

• Python Fire is a simple way to create a CLI in Python. [1]
• Python Fire is a helpful tool for developing and debugging Python code. [2]
• Python Fire helps with exploring existing code or turning other people's code into a CLI. [3]
• Python Fire makes transitioning between Bash and Python easier. [4]
• Python Fire makes using a Python REPL easier by setting up the REPL with the modules and variables you'll need already imported and created. [5]

Installation

pip install fire

Basic Usage

You can call Fire on any Python object:
functions, classes, modules, objects, dictionaries, lists, tuples, etc. They all work!

Here's a simple example.

import fire

class Calculator(object):
  """A simple calculator class."""

  def double(self, number):
    return 2 * number

if __name__ == '__main__':
  fire.Fire(Calculator)

Then, from the command line, you can run:

python calculator.py double 10  # 20
python calculator.py double --number=15  # 30

To learn how Fire behaves on functions, objects, dicts, lists, etc, and to learn about Fire's other features, see the Using a Fire CLI page.

Why is it called Fire?

When you call Fire, it fires off (executes) your command.

Reference

Setup	Command	Notes
install	pip install fire

Creating a CLI	Command	Notes
import	import fire
Call	fire.Fire()	Turns the current module into a Fire CLI.
Call	fire.Fire(component)	Turns component into a Fire CLI.

Using a CLI	Command	Notes
Help	command -- --help
REPL	command -- --interactive	Enters interactive mode.
Separator	command -- --separator=X	This sets the separator to X. The default separator is -.
Completion	command -- --completion	Generate a completion script for the CLI.
Trace	command -- --trace	Gets a Fire trace for the command.
Verbose	command -- --verbose
Note that flags are separated from the Fire command by an isolated -- arg.

Disclaimer

This is not an official Google product.