python-inquirer

Inquirer is a Python library designed to simplify interactive command-line interfaces. It focuses on easing the process of:

• Asking questions: Presenting various prompt types to the end user.
• Parsing: Converting user input into usable data types.
• Validating: Ensuring answers meet specific criteria before proceeding.
• Managing hierarchical prompts: Handling complex, nested question flows.
• Providing error feedback: Communicating issues with user input clearly.

You can change the colorscheme and icons by passing a theme object from inquirer.themes to the prompt.

Pre-defined themes include:

• Default
• GreenPassion
• BlueComposure

Note: Not all terminals support all colors or Unicode characters. Test your theme in your target environment.

To use inquirer, follow these two steps:

1. Create an array (list) of Question objects.
2. Call inquirer.prompt(questions).

The prompt function will interact with the user and return a dictionary where the keys are the question names and the values are the user's responses.

import inquirer
from inquirer import Text

questions = [
    Text('name', message="What's your name?"),
    Text('surname', message="What's your surname, {name}")
]

answers = inquirer.prompt(questions)
# answers will be something like: {'name': 'John', 'surname': 'Doe'}

Install the inquirer package using pip to start building interactive command line interfaces.

pip install inquirer

When defining choices for List or Checkbox questions, you can provide a tuple in the format (value, label).

Inquirer uses the TaggedValue abstraction to handle these. The value is what will be returned in the final answers dictionary, while the label is what the user actually sees in the terminal interface. This allows you to present human-readable strings while working with programmatic identifiers (like IDs or enums) in your code.

from inquirer import List

# The user sees 'Option A', but the result will be 1
question = List(
    "choice", 
    message="Pick one", 
    choices=[(1, "Option A"), (2, "Option B")]
)

You can customize the visual appearance of the inquirer prompts by applying a theme. The implementation details can be found in examples/theme.py.

# See examples/theme.py for full implementation

The text question type allows you to prompt the user for a string input. You can find the implementation details in the examples/text.py file.

# See examples/text.py for full implementation

Use inquirer.Checkbox to allow users to select one or more options from a list.

Options:

• choices: A list of strings representing the available options.
• carousel: If set to True, the selection will rotate (wrapping from the last choice back to the first and vice versa).
• locked: A list of choices that cannot be removed by the user. This is useful for enforcing that certain options must remain selected.

import inquirer

questions = [
  inquirer.Checkbox('interests',
                    message="What are you interested in?",
                    choices=['Computers', 'Books', 'Science', 'Nature', 'Fantasy', 'History'],
                    ),
]
answers = inquirer.prompt(questions)

Use inquirer.Editor when you need to collect large amounts of text. This opens the user's external text editor.

Inquirer determines the editor using the following priority:

1. The $VISUAL environment variable.
2. The $EDITOR environment variable.
3. System fallbacks in order: vim -> emacs -> nano.

import inquirer

questions = [
  inquirer.Editor('long_text', message="Provide long text")
]
answers = inquirer.prompt(questions)

The checkbox question type allows users to select multiple options from a list.

Keyboard Shortcuts

In addition to standard controls, checkbox supports:

• Ctrl + A: Select all choices.
• Ctrl + R: Un-select all choices (including defaults).
• Ctrl + I: Invert/toggle all choices.

Using Tagged Choices

You can provide a list of tuples to the choices parameter instead of plain strings. The first element of the tuple is the label displayed to the user, and the second element is the actual value returned by the question. This is useful when you want the user to select a human-readable string but your code needs a different data type (like an ID or object).

# Example of tagged choices (see examples/checkbox_tagged.py)
# choices = [("Label 1", "value1"), ("Label 2", "value2")]

The confirm question type prompts the user for a boolean (Yes/No) response. You can find the implementation details in the examples/confirm.py file.

# See examples/confirm.py for full implementation