| from typing import Any, Generic, List, Optional, TextIO, TypeVar, Union, overload |
| |
| from . import get_console |
| from .console import Console |
| from .text import Text, TextType |
| |
| PromptType = TypeVar("PromptType") |
| DefaultType = TypeVar("DefaultType") |
| |
| |
| class PromptError(Exception): |
| """Exception base class for prompt related errors.""" |
| |
| |
| class InvalidResponse(PromptError): |
| """Exception to indicate a response was invalid. Raise this within process_response() to indicate an error |
| and provide an error message. |
| |
| Args: |
| message (Union[str, Text]): Error message. |
| """ |
| |
| def __init__(self, message: TextType) -> None: |
| self.message = message |
| |
| def __rich__(self) -> TextType: |
| return self.message |
| |
| |
| class PromptBase(Generic[PromptType]): |
| """Ask the user for input until a valid response is received. This is the base class, see one of |
| the concrete classes for examples. |
| |
| Args: |
| prompt (TextType, optional): Prompt text. Defaults to "". |
| console (Console, optional): A Console instance or None to use global console. Defaults to None. |
| password (bool, optional): Enable password input. Defaults to False. |
| choices (List[str], optional): A list of valid choices. Defaults to None. |
| show_default (bool, optional): Show default in prompt. Defaults to True. |
| show_choices (bool, optional): Show choices in prompt. Defaults to True. |
| """ |
| |
| response_type: type = str |
| |
| validate_error_message = "[prompt.invalid]Please enter a valid value" |
| illegal_choice_message = ( |
| "[prompt.invalid.choice]Please select one of the available options" |
| ) |
| prompt_suffix = ": " |
| |
| choices: Optional[List[str]] = None |
| |
| def __init__( |
| self, |
| prompt: TextType = "", |
| *, |
| console: Optional[Console] = None, |
| password: bool = False, |
| choices: Optional[List[str]] = None, |
| show_default: bool = True, |
| show_choices: bool = True, |
| ) -> None: |
| self.console = console or get_console() |
| self.prompt = ( |
| Text.from_markup(prompt, style="prompt") |
| if isinstance(prompt, str) |
| else prompt |
| ) |
| self.password = password |
| if choices is not None: |
| self.choices = choices |
| self.show_default = show_default |
| self.show_choices = show_choices |
| |
| @classmethod |
| @overload |
| def ask( |
| cls, |
| prompt: TextType = "", |
| *, |
| console: Optional[Console] = None, |
| password: bool = False, |
| choices: Optional[List[str]] = None, |
| show_default: bool = True, |
| show_choices: bool = True, |
| default: DefaultType, |
| stream: Optional[TextIO] = None, |
| ) -> Union[DefaultType, PromptType]: |
| ... |
| |
| @classmethod |
| @overload |
| def ask( |
| cls, |
| prompt: TextType = "", |
| *, |
| console: Optional[Console] = None, |
| password: bool = False, |
| choices: Optional[List[str]] = None, |
| show_default: bool = True, |
| show_choices: bool = True, |
| stream: Optional[TextIO] = None, |
| ) -> PromptType: |
| ... |
| |
| @classmethod |
| def ask( |
| cls, |
| prompt: TextType = "", |
| *, |
| console: Optional[Console] = None, |
| password: bool = False, |
| choices: Optional[List[str]] = None, |
| show_default: bool = True, |
| show_choices: bool = True, |
| default: Any = ..., |
| stream: Optional[TextIO] = None, |
| ) -> Any: |
| """Shortcut to construct and run a prompt loop and return the result. |
| |
| Example: |
| >>> filename = Prompt.ask("Enter a filename") |
| |
| Args: |
| prompt (TextType, optional): Prompt text. Defaults to "". |
| console (Console, optional): A Console instance or None to use global console. Defaults to None. |
| password (bool, optional): Enable password input. Defaults to False. |
| choices (List[str], optional): A list of valid choices. Defaults to None. |
| show_default (bool, optional): Show default in prompt. Defaults to True. |
| show_choices (bool, optional): Show choices in prompt. Defaults to True. |
| stream (TextIO, optional): Optional text file open for reading to get input. Defaults to None. |
| """ |
| _prompt = cls( |
| prompt, |
| console=console, |
| password=password, |
| choices=choices, |
| show_default=show_default, |
| show_choices=show_choices, |
| ) |
| return _prompt(default=default, stream=stream) |
| |
| def render_default(self, default: DefaultType) -> Text: |
| """Turn the supplied default in to a Text instance. |
| |
| Args: |
| default (DefaultType): Default value. |
| |
| Returns: |
| Text: Text containing rendering of default value. |
| """ |
| return Text(f"({default})", "prompt.default") |
| |
| def make_prompt(self, default: DefaultType) -> Text: |
| """Make prompt text. |
| |
| Args: |
| default (DefaultType): Default value. |
| |
| Returns: |
| Text: Text to display in prompt. |
| """ |
| prompt = self.prompt.copy() |
| prompt.end = "" |
| |
| if self.show_choices and self.choices: |
| _choices = "/".join(self.choices) |
| choices = f"[{_choices}]" |
| prompt.append(" ") |
| prompt.append(choices, "prompt.choices") |
| |
| if ( |
| default != ... |
| and self.show_default |
| and isinstance(default, (str, self.response_type)) |
| ): |
| prompt.append(" ") |
| _default = self.render_default(default) |
| prompt.append(_default) |
| |
| prompt.append(self.prompt_suffix) |
| |
| return prompt |
| |
| @classmethod |
| def get_input( |
| cls, |
| console: Console, |
| prompt: TextType, |
| password: bool, |
| stream: Optional[TextIO] = None, |
| ) -> str: |
| """Get input from user. |
| |
| Args: |
| console (Console): Console instance. |
| prompt (TextType): Prompt text. |
| password (bool): Enable password entry. |
| |
| Returns: |
| str: String from user. |
| """ |
| return console.input(prompt, password=password, stream=stream) |
| |
| def check_choice(self, value: str) -> bool: |
| """Check value is in the list of valid choices. |
| |
| Args: |
| value (str): Value entered by user. |
| |
| Returns: |
| bool: True if choice was valid, otherwise False. |
| """ |
| assert self.choices is not None |
| return value.strip() in self.choices |
| |
| def process_response(self, value: str) -> PromptType: |
| """Process response from user, convert to prompt type. |
| |
| Args: |
| value (str): String typed by user. |
| |
| Raises: |
| InvalidResponse: If ``value`` is invalid. |
| |
| Returns: |
| PromptType: The value to be returned from ask method. |
| """ |
| value = value.strip() |
| try: |
| return_value: PromptType = self.response_type(value) |
| except ValueError: |
| raise InvalidResponse(self.validate_error_message) |
| |
| if self.choices is not None and not self.check_choice(value): |
| raise InvalidResponse(self.illegal_choice_message) |
| |
| return return_value |
| |
| def on_validate_error(self, value: str, error: InvalidResponse) -> None: |
| """Called to handle validation error. |
| |
| Args: |
| value (str): String entered by user. |
| error (InvalidResponse): Exception instance the initiated the error. |
| """ |
| self.console.print(error) |
| |
| def pre_prompt(self) -> None: |
| """Hook to display something before the prompt.""" |
| |
| @overload |
| def __call__(self, *, stream: Optional[TextIO] = None) -> PromptType: |
| ... |
| |
| @overload |
| def __call__( |
| self, *, default: DefaultType, stream: Optional[TextIO] = None |
| ) -> Union[PromptType, DefaultType]: |
| ... |
| |
| def __call__(self, *, default: Any = ..., stream: Optional[TextIO] = None) -> Any: |
| """Run the prompt loop. |
| |
| Args: |
| default (Any, optional): Optional default value. |
| |
| Returns: |
| PromptType: Processed value. |
| """ |
| while True: |
| self.pre_prompt() |
| prompt = self.make_prompt(default) |
| value = self.get_input(self.console, prompt, self.password, stream=stream) |
| if value == "" and default != ...: |
| return default |
| try: |
| return_value = self.process_response(value) |
| except InvalidResponse as error: |
| self.on_validate_error(value, error) |
| continue |
| else: |
| return return_value |
| |
| |
| class Prompt(PromptBase[str]): |
| """A prompt that returns a str. |
| |
| Example: |
| >>> name = Prompt.ask("Enter your name") |
| |
| |
| """ |
| |
| response_type = str |
| |
| |
| class IntPrompt(PromptBase[int]): |
| """A prompt that returns an integer. |
| |
| Example: |
| >>> burrito_count = IntPrompt.ask("How many burritos do you want to order") |
| |
| """ |
| |
| response_type = int |
| validate_error_message = "[prompt.invalid]Please enter a valid integer number" |
| |
| |
| class FloatPrompt(PromptBase[int]): |
| """A prompt that returns a float. |
| |
| Example: |
| >>> temperature = FloatPrompt.ask("Enter desired temperature") |
| |
| """ |
| |
| response_type = float |
| validate_error_message = "[prompt.invalid]Please enter a number" |
| |
| |
| class Confirm(PromptBase[bool]): |
| """A yes / no confirmation prompt. |
| |
| Example: |
| >>> if Confirm.ask("Continue"): |
| run_job() |
| |
| """ |
| |
| response_type = bool |
| validate_error_message = "[prompt.invalid]Please enter Y or N" |
| choices: List[str] = ["y", "n"] |
| |
| def render_default(self, default: DefaultType) -> Text: |
| """Render the default as (y) or (n) rather than True/False.""" |
| yes, no = self.choices |
| return Text(f"({yes})" if default else f"({no})", style="prompt.default") |
| |
| def process_response(self, value: str) -> bool: |
| """Convert choices to a bool.""" |
| value = value.strip().lower() |
| if value not in self.choices: |
| raise InvalidResponse(self.validate_error_message) |
| return value == self.choices[0] |
| |
| |
| if __name__ == "__main__": # pragma: no cover |
| |
| from pip._vendor.rich import print |
| |
| if Confirm.ask("Run [i]prompt[/i] tests?", default=True): |
| while True: |
| result = IntPrompt.ask( |
| ":rocket: Enter a number between [b]1[/b] and [b]10[/b]", default=5 |
| ) |
| if result >= 1 and result <= 10: |
| break |
| print(":pile_of_poo: [prompt.invalid]Number must be between 1 and 10") |
| print(f"number={result}") |
| |
| while True: |
| password = Prompt.ask( |
| "Please enter a password [cyan](must be at least 5 characters)", |
| password=True, |
| ) |
| if len(password) >= 5: |
| break |
| print("[prompt.invalid]password too short") |
| print(f"password={password!r}") |
| |
| fruit = Prompt.ask("Enter a fruit", choices=["apple", "orange", "pear"]) |
| print(f"fruit={fruit!r}") |
| |
| else: |
| print("[b]OK :loudly_crying_face:") |