Wonders with Click: Streamline your CLI Experience

Introduction

In this blog📃we will be delving into the fascinating dimensions of Click, a Python library that can streamline your CLI performance and reach. We will be discussing the concepts necessary to create a basic and compact CLI. This blog would help you to produce and organize 📚 better CLI for your clients🤝.

What is Click anyway??

Click is a Python package 📦 that helps one to fasten their CLI utility development. This package acts as an easier option ✅ compared to other Python packages to develop Command Line Interfaces. It is a better option as it requires minimal coding and comes with many built in features that streamline the development features.

Mastering the basics of Click

Installation:

To install click run the following command.

pip install click

coding:

First create a file named main.py and open the file with your preferred code editor/ide. Now induce the following code snippet to create a basic cli tool🧰 in main.py

import click

@click.command()
def say_hello():
  click.echo("Hello Bob")

# runs when the file is run directly and not imported
if __name__ == "__main__": 
  say_hello()

Here we use the click.command decorator to give the function some more features to make it suitable for a cli command(eg: commit, merge, init, etc in Git). And click.echo is a customized version of python print function that suits the need of click.

having multiple commands

import click

@click.group()
def cli():
  pass

@click.command()
@click.option('--name', prompt='Your name',
              help='The person to greet.')
def say_hello(name):
  click.echo(f'Hello {name}!')

@click.command()
@click.option('--name', prompt='Your name',
              help='The person to greet.')
def say_bye(name):
  click.echo(f'Goodbye {name}!')

@click.command()
@click.option('--num', prompt='Enter a number',type=int ,
              help='The person to greet.')
def give_square(num):
  click.echo(num*num)


# Registering the commands with the CLI
cli.add_command(say_hello)
cli.add_command(say_bye)
cli.add_command(give_square)


if __name__ == "__main__": 
  cli()

The click.option decorator converts the function into a command with ability to take an optional value.

To use this snippet run the following command in the terminal,

python main.py say_hello --name=Kris

working with arguments

import click

@click.command()
@click.argument('name')
def say_hello(name):
  click.echo(f"Hello {name}")

# runs when the file is run directly and not imported
if __name__ == "__main__": 
  say_hello()

The click.argument decorator converts the function into a command with ability to take an argument which is to be provided and is required by the cli.

To use this code snippet run the following command in the terminal,

python main.py bob

Conclusion

Click makes building command-line interfaces in Python simple and intuitive. With support for multiple commands, options, and arguments, it’s a powerful💪tool that can scale from simple to complex use cases.

In a nutshell:

• Command Groups allow you to organize multiple commands.
• Commands define the actions your CLI will perform.
• Options & Arguments allow user input to customize command behavior.

Start experimenting with Click for your next Python
project and see how easy it is to build user-friendly CLI tools!