Welcome to Click¶

Click is a Python package for creating beautiful command line interfaces in a composable way with as little code as necessary. It’s the “Command Line Interface Creation Kit”. It’s highly configurable but comes with sensible defaults out of the box.
It aims to make the process of writing command line tools quick and fun while also preventing any frustration caused by the inability to implement an intended CLI API.
Click in three points:
arbitrary nesting of commands
automatic help page generation
supports lazy loading of subcommands at runtime
What does it look like? Here is an example of a simple Click program:
import click
@click.command()
@click.option('--count', default=1, help='Number of greetings.')
@click.option('--name', prompt='Your name',
help='The person to greet.')
def hello(count, name):
"""Simple program that greets NAME for a total of COUNT times."""
for x in range(count):
click.echo(f"Hello {name}!")
if __name__ == '__main__':
hello()
And what it looks like when run:
$ python hello.py --count=3
Your name: John
Hello John!
Hello John!
Hello John!
It automatically generates nicely formatted help pages:
$ python hello.py --help
Usage: hello.py [OPTIONS]
Simple program that greets NAME for a total of COUNT times.
Options:
--count INTEGER Number of greetings.
--name TEXT The person to greet.
--help Show this message and exit.
You can get the library directly from PyPI:
pip install click
Documentation¶
This part of the documentation guides you through all of the library’s usage patterns.
- Why Click?
- Quickstart
- Packaging Entry Points
- Virtualenv
- Setuptools Integration
- Parameters
- Parameter Types
- Options
- Option Decorator
- Basic Example
- Setting a Default
- Multi Value Options
- Multi Value Options as Tuples
- Multiple Options
- Counting
- Boolean
- Flag Value
- Feature Switches
- Prompting
- Dynamic Defaults for Prompts
- Callbacks and Eager Options
- Values from Environment Variables
- Multiple Values from Environment Values
- Other Prefix Characters
- Callbacks for Validation
- Optional Value
- Options Shortcut Decorators
- Arguments
- Commands and Groups
- Help Pages
- User Input Prompts
- Complex Applications
- Advanced Patterns
- Testing Click Applications
- Utilities
- Shell Completion
- Exception Handling
- Unicode Support
- Windows Console Notes
API Reference¶
If you are looking for information on a specific function, class, or method, this part of the documentation is for you.
Miscellaneous Pages¶
- click-contrib
- BSD-3-Clause License
- Changes
- Version 8.2.0
- Version 8.1.8
- Version 8.1.7
- Version 8.1.6
- Version 8.1.5
- Version 8.1.4
- Version 8.1.3
- Version 8.1.2
- Version 8.1.1
- Version 8.1.0
- Version 8.0.4
- Version 8.0.3
- Version 8.0.2
- Version 8.0.1
- Version 8.0.0
- Version 7.1.2
- Version 7.1.1
- Version 7.1
- Version 7.0
- Version 6.7
- Version 6.6
- Version 6.4
- Version 6.3
- Version 6.2
- Version 6.1
- Version 6.0
- Version 5.1
- Version 5.0
- Version 4.1
- Version 4.0
- Version 3.3
- Version 3.2
- Version 3.1
- Version 3.0
- Version 2.6
- Version 2.5
- Version 2.4
- Version 2.3
- Version 2.2
- Version 2.1
- Version 2.0
- Version 1.1
- Version 1.0