Python Fire

Python Fire is a library for automatically generating 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

To install Python Fire with pip, run: pip install fire

To install Python Fire with conda, run: conda install fire -c conda-forge

To install Python Fire from source, first clone the repository and then run: python setup.py install

Basic Usage

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

Here's an example of calling Fire on a class.

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.

For additional examples, see The Python Fire Guide.

Why is it called Fire?

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

Where can I learn more?

Please see The Python Fire Guide.

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 [shell]`	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.