"""Functions to collect user input. """ from milc import cli, format_ansi def yesno(prompt, *args, default=None, **kwargs): """Displays prompt to the user and gets a yes or no response. Returns True for a yes and False for a no. If you add `--yes` and `--no` arguments to your program the user can answer questions by passing command line flags. @add_argument('-y', '--yes', action='store_true', arg_only=True, help='Answer yes to all questions.') @add_argument('-n', '--no', action='store_true', arg_only=True, help='Answer no to all questions.') Arguments: prompt The prompt to present to the user. Can include ANSI and format strings like milc's `cli.echo()`. default Whether to default to a Yes or No when the user presses enter. None- force the user to enter Y or N True- Default to yes False- Default to no """ if not args and kwargs: args = kwargs if 'no' in cli.args and cli.args.no: return False if 'yes' in cli.args and cli.args.yes: return True if default is not None: if default: prompt = prompt + ' [Y/n] ' else: prompt = prompt + ' [y/N] ' while True: cli.echo('') answer = input(format_ansi(prompt % args)) cli.echo('') if not answer and prompt is not None: return default elif answer.lower() in ['y', 'yes']: return True elif answer.lower() in ['n', 'no']: return False def question(prompt, *args, default=None, confirm=False, answer_type=str, validate=None, **kwargs): """Prompt the user to answer a question with a free-form input. Arguments: prompt The prompt to present to the user. Can include ANSI and format strings like milc's `cli.echo()`. default The value to return when the user doesn't enter any value. Use None to prompt until they enter a value. confirm Present the user with a confirmation dialog before accepting their answer. answer_type Specify a type function for the answer. Will re-prompt the user if the function raises any errors. Common choices here include int, float, and decimal.Decimal. validate This is an optional function that can be used to validate the answer. It should return True or False and have the following signature: def function_name(answer, *args, **kwargs): """ if not args and kwargs: args = kwargs if default is not None: prompt = '%s [%s] ' % (prompt, default) while True: cli.echo('') answer = input(format_ansi(prompt % args)) cli.echo('') if answer: if validate is not None and not validate(answer, *args, **kwargs): continue elif confirm: if yesno('Is the answer "%s" correct?', answer, default=True): try: return answer_type(answer) except Exception as e: cli.log.error('Could not convert answer (%s) to type %s: %s', answer, answer_type.__name__, str(e)) else: try: return answer_type(answer) except Exception as e: cli.log.error('Could not convert answer (%s) to type %s: %s', answer, answer_type.__name__, str(e)) elif default is not None: return default def choice(heading, options, *args, default=None, confirm=False, prompt='Please enter your choice: ', **kwargs): """Present the user with a list of options and let them pick one. Users can enter either the number or the text of their choice. This will return the value of the item they choose, not the numerical index. Arguments: heading The text to place above the list of options. options A sequence of items to choose from. default The index of the item to return when the user doesn't enter any value. Use None to prompt until they enter a value. confirm Present the user with a confirmation dialog before accepting their answer. prompt The prompt to present to the user. Can include ANSI and format strings like milc's `cli.echo()`. """ if not args and kwargs: args = kwargs if prompt and default: prompt = prompt + ' [%s] ' % (default + 1,) while True: # Prompt for an answer. cli.echo('') cli.echo(heading % args) cli.echo('') for i, option in enumerate(options, 1): cli.echo('\t{fg_cyan}%d.{fg_reset} %s', i, option) cli.echo('') answer = input(format_ansi(prompt)) cli.echo('') # If the user types in one of the options exactly use that if answer in options: return answer # Massage the answer into a valid integer if answer == '' and default: answer = default else: try: answer = int(answer) - 1 except Exception: # Normally we would log the exception here, but in the interest of clean UI we do not. cli.log.error('Invalid choice: %s', answer + 1) continue # Validate the answer if answer >= len(options) or answer < 0: cli.log.error('Invalid choice: %s', answer + 1) continue if confirm and not yesno('Is the answer "%s" correct?', answer + 1, default=True): continue # Return the answer they chose. return options[answer]