开发命令行工具的十个 Click 库高级参数

# 导入click库
import click

# 定义一个点击装饰器
@click.command()
# 定义函数处理程序逻辑
def hello():
    """简单的命令，输出Hello"""
    click.echo("Hello!")

# 主函数调用
if __name__ == '__main__':
    hello()
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Hello!
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import click

@click.command()
@click.argument('name')  # 使用参数
def greet(name):
    """接收name参数，打印个性化问候"""
    click.echo(f"Hello, {name}!")

if __name__ == '__main__':
    greet()
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$ python app.py Alice
Hello, Alice!
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import click

@click.command()
@click.option('--age', type=int, help="Your age in years.")  # 声明age选项，要求为int类型
def display(age):
    """显示年龄"""
    click.echo(f"Your entered age is: {age}")

if __name__ == '__main__':
    display()
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$ python app.py --age 26
Your entered age is: 26
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import click

@click.command()
@click.option('--temperature', default=20, help="Room temperature in degrees Celsius.")
def adjust_temp(temperature):
    """调整温度设置"""
    click.echo(f"The current room temperature is set to: {temperature}°C")

if __name__ == '__main__':
    adjust_temp()
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The current room temperature is set to: 20°C
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import click

@click.command()
@click.confirmation_option(prompt='Are you sure you want to proceed?')
def danger():
    """需要用户确认的操作"""
    click.echo("Action performed!")

if __name__ == '__main__':
    danger()
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import click

@click.command()
@click.option('--colors', multiple=True, help="List of colors")
def show_colors(colors):
    """展示所有提供的颜色"""
    for color in colors:
        click.echo(f"You chose the color: {color}")

if __name__ == '__main__':
    show_colors()
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$ python app.py --colors red --colors green
You chose the color: red
You chose the color: green
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import click

@click.command()
@click.argument('input_file', type=click.File('r'))
@click.argument('output_file', type=click.File('w'))
def copy(input_file, output_file):
    """拷贝内容至另一文件"""
    output_file.write(input_file.read())
    click.echo('File copied successfully!')

if __name__ == '__main__':
    copy()
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import click

@click.group()
def cli():
    """主组"""

@cli.command()
def initdb():
    click.echo('Initialized the database')

@cli.command()
def dropdb():
    click.echo('Dropped the database')

if __name__ == '__main__':
    cli()
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import click

def validate_age(ctx, param, value):
    try:
        if value < 0:
            raise ValueError
        return value
    except ValueError:
        raise click.BadParameter('Age must be a non-negative integer.')

@click.command()
@click.option('--age', callback=validate_age, type=int)
def process(age):
    """验证年龄正确性"""
    click.echo(f"Processed your valid age: {age}")

if __name__ == '__main__':
    process()
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import os
import click

def find_files(dir, ext):
    """实际查找文件方法"""
    results = []
    for dirpath, dirnames, filenames in os.walk(dir):
        for filename in filenames:
            if filename.endswith(ext):
                results.append(os.path.join(dirpath, filename))
    return results

@click.command()
@click.option('-d', '--dir', required=True, type=click.Path(exists=True), help='Directory to search.')
@click.option('-e', '--ext', required=True, help='File extension.')
def finder(dir, ext):
    """命令行应用：寻找扩展名为EXT的文件"""
    files = find_files(dir, ext)
    if not files:
        click.echo('No matching files found.')
    else:
        for file in files:
            click.echo(file)

if __name__ == '__main__':
    finder()
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