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.

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	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.

Troubleshooting

Specific python module names have been known to throw errors. IPython contains several builtin modules. If a user-created module of the same name exists on the pythonpath in front of the builtin modules it 'covers' the orgional file. This results in the wrong module being imported and the consequential error seen.

If you are incountering an error and your module is named any of the following:

• sys.py
• linecache.py
• cmd.py
• bdb.py
• repr.py
• os.py
• re.py
• pprint.py
• traceback.py

The recommended course of action is to alter your filename.

Disclaimer

This is not an official Google product.