Source code for click.termui

import inspect
import io
import itertools
import os
import struct
import sys

from ._compat import DEFAULT_COLUMNS
from ._compat import get_winterm_size
from ._compat import isatty
from ._compat import raw_input
from ._compat import string_types
from ._compat import strip_ansi
from ._compat import text_type
from ._compat import WIN
from .exceptions import Abort
from .exceptions import UsageError
from .globals import resolve_color_default
from .types import Choice
from .types import convert_type
from .types import Path
from .utils import echo
from .utils import LazyFile

# The prompt functions to use.  The doc tools currently override these
# functions to customize how they work.
visible_prompt_func = raw_input

_ansi_colors = {
    "black": 30,
    "red": 31,
    "green": 32,
    "yellow": 33,
    "blue": 34,
    "magenta": 35,
    "cyan": 36,
    "white": 37,
    "reset": 39,
    "bright_black": 90,
    "bright_red": 91,
    "bright_green": 92,
    "bright_yellow": 93,
    "bright_blue": 94,
    "bright_magenta": 95,
    "bright_cyan": 96,
    "bright_white": 97,
}
_ansi_reset_all = "\033[0m"


def hidden_prompt_func(prompt):
    import getpass

    return getpass.getpass(prompt)


def _build_prompt(
    text, suffix, show_default=False, default=None, show_choices=True, type=None
):
    prompt = text
    if type is not None and show_choices and isinstance(type, Choice):
        prompt += " ({})".format(", ".join(map(str, type.choices)))
    if default is not None and show_default:
        prompt = "{} [{}]".format(prompt, _format_default(default))
    return prompt + suffix


def _format_default(default):
    if isinstance(default, (io.IOBase, LazyFile)) and hasattr(default, "name"):
        return default.name

    return default


[docs]def prompt( text, default=None, hide_input=False, confirmation_prompt=False, type=None, value_proc=None, prompt_suffix=": ", show_default=True, err=False, show_choices=True, ): """Prompts a user for input. This is a convenience function that can be used to prompt a user for input later. If the user aborts the input by sending a interrupt signal, this function will catch it and raise a :exc:`Abort` exception. .. versionadded:: 7.0 Added the show_choices parameter. .. versionadded:: 6.0 Added unicode support for cmd.exe on Windows. .. versionadded:: 4.0 Added the `err` parameter. :param text: the text to show for the prompt. :param default: the default value to use if no input happens. If this is not given it will prompt until it's aborted. :param hide_input: if this is set to true then the input value will be hidden. :param confirmation_prompt: asks for confirmation for the value. :param type: the type to use to check the value against. :param value_proc: if this parameter is provided it's a function that is invoked instead of the type conversion to convert a value. :param prompt_suffix: a suffix that should be added to the prompt. :param show_default: shows or hides the default value in the prompt. :param err: if set to true the file defaults to ``stderr`` instead of ``stdout``, the same as with echo. :param show_choices: Show or hide choices if the passed type is a Choice. For example if type is a Choice of either day or week, show_choices is true and text is "Group by" then the prompt will be "Group by (day, week): ". """ result = None def prompt_func(text): f = hidden_prompt_func if hide_input else visible_prompt_func try: # Write the prompt separately so that we get nice # coloring through colorama on Windows echo(text, nl=False, err=err) return f("") except (KeyboardInterrupt, EOFError): # getpass doesn't print a newline if the user aborts input with ^C. # Allegedly this behavior is inherited from getpass(3). # A doc bug has been filed at https://bugs.python.org/issue24711 if hide_input: echo(None, err=err) raise Abort() if value_proc is None: value_proc = convert_type(type, default) prompt = _build_prompt( text, prompt_suffix, show_default, default, show_choices, type ) while 1: while 1: value = prompt_func(prompt) if value: break elif default is not None: if isinstance(value_proc, Path): # validate Path default value(exists, dir_okay etc.) value = default break return default try: result = value_proc(value) except UsageError as e: echo("Error: {}".format(e.message), err=err) # noqa: B306 continue if not confirmation_prompt: return result while 1: value2 = prompt_func("Repeat for confirmation: ") if value2: break if value == value2: return result echo("Error: the two entered values do not match", err=err)
[docs]def confirm( text, default=False, abort=False, prompt_suffix=": ", show_default=True, err=False ): """Prompts for confirmation (yes/no question). If the user aborts the input by sending a interrupt signal this function will catch it and raise a :exc:`Abort` exception. .. versionadded:: 4.0 Added the `err` parameter. :param text: the question to ask. :param default: the default for the prompt. :param abort: if this is set to `True` a negative answer aborts the exception by raising :exc:`Abort`. :param prompt_suffix: a suffix that should be added to the prompt. :param show_default: shows or hides the default value in the prompt. :param err: if set to true the file defaults to ``stderr`` instead of ``stdout``, the same as with echo. """ prompt = _build_prompt( text, prompt_suffix, show_default, "Y/n" if default else "y/N" ) while 1: try: # Write the prompt separately so that we get nice # coloring through colorama on Windows echo(prompt, nl=False, err=err) value = visible_prompt_func("").lower().strip() except (KeyboardInterrupt, EOFError): raise Abort() if value in ("y", "yes"): rv = True elif value in ("n", "no"): rv = False elif value == "": rv = default else: echo("Error: invalid input", err=err) continue break if abort and not rv: raise Abort() return rv
[docs]def get_terminal_size(): """Returns the current size of the terminal as tuple in the form ``(width, height)`` in columns and rows. """ # If shutil has get_terminal_size() (Python 3.3 and later) use that if sys.version_info >= (3, 3): import shutil shutil_get_terminal_size = getattr(shutil, "get_terminal_size", None) if shutil_get_terminal_size: sz = shutil_get_terminal_size() return sz.columns, sz.lines # We provide a sensible default for get_winterm_size() when being invoked # inside a subprocess. Without this, it would not provide a useful input. if get_winterm_size is not None: size = get_winterm_size() if size == (0, 0): return (79, 24) else: return size def ioctl_gwinsz(fd): try: import fcntl import termios cr = struct.unpack("hh", fcntl.ioctl(fd, termios.TIOCGWINSZ, "1234")) except Exception: return return cr cr = ioctl_gwinsz(0) or ioctl_gwinsz(1) or ioctl_gwinsz(2) if not cr: try: fd = os.open(os.ctermid(), os.O_RDONLY) try: cr = ioctl_gwinsz(fd) finally: os.close(fd) except Exception: pass if not cr or not cr[0] or not cr[1]: cr = (os.environ.get("LINES", 25), os.environ.get("COLUMNS", DEFAULT_COLUMNS)) return int(cr[1]), int(cr[0])
[docs]def echo_via_pager(text_or_generator, color=None): """This function takes a text and shows it via an environment specific pager on stdout. .. versionchanged:: 3.0 Added the `color` flag. :param text_or_generator: the text to page, or alternatively, a generator emitting the text to page. :param color: controls if the pager supports ANSI colors or not. The default is autodetection. """ color = resolve_color_default(color) if inspect.isgeneratorfunction(text_or_generator): i = text_or_generator() elif isinstance(text_or_generator, string_types): i = [text_or_generator] else: i = iter(text_or_generator) # convert every element of i to a text type if necessary text_generator = (el if isinstance(el, string_types) else text_type(el) for el in i) from ._termui_impl import pager return pager(itertools.chain(text_generator, "\n"), color)
[docs]def progressbar( iterable=None, length=None, label=None, show_eta=True, show_percent=None, show_pos=False, item_show_func=None, fill_char="#", empty_char="-", bar_template="%(label)s [%(bar)s] %(info)s", info_sep=" ", width=36, file=None, color=None, ): """This function creates an iterable context manager that can be used to iterate over something while showing a progress bar. It will either iterate over the `iterable` or `length` items (that are counted up). While iteration happens, this function will print a rendered progress bar to the given `file` (defaults to stdout) and will attempt to calculate remaining time and more. By default, this progress bar will not be rendered if the file is not a terminal. The context manager creates the progress bar. When the context manager is entered the progress bar is already created. With every iteration over the progress bar, the iterable passed to the bar is advanced and the bar is updated. When the context manager exits, a newline is printed and the progress bar is finalized on screen. Note: The progress bar is currently designed for use cases where the total progress can be expected to take at least several seconds. Because of this, the ProgressBar class object won't display progress that is considered too fast, and progress where the time between steps is less than a second. No printing must happen or the progress bar will be unintentionally destroyed. Example usage:: with progressbar(items) as bar: for item in bar: do_something_with(item) Alternatively, if no iterable is specified, one can manually update the progress bar through the `update()` method instead of directly iterating over the progress bar. The update method accepts the number of steps to increment the bar with:: with progressbar(length=chunks.total_bytes) as bar: for chunk in chunks: process_chunk(chunk) bar.update(chunks.bytes) .. versionadded:: 2.0 .. versionadded:: 4.0 Added the `color` parameter. Added a `update` method to the progressbar object. :param iterable: an iterable to iterate over. If not provided the length is required. :param length: the number of items to iterate over. By default the progressbar will attempt to ask the iterator about its length, which might or might not work. If an iterable is also provided this parameter can be used to override the length. If an iterable is not provided the progress bar will iterate over a range of that length. :param label: the label to show next to the progress bar. :param show_eta: enables or disables the estimated time display. This is automatically disabled if the length cannot be determined. :param show_percent: enables or disables the percentage display. The default is `True` if the iterable has a length or `False` if not. :param show_pos: enables or disables the absolute position display. The default is `False`. :param item_show_func: a function called with the current item which can return a string to show the current item next to the progress bar. Note that the current item can be `None`! :param fill_char: the character to use to show the filled part of the progress bar. :param empty_char: the character to use to show the non-filled part of the progress bar. :param bar_template: the format string to use as template for the bar. The parameters in it are ``label`` for the label, ``bar`` for the progress bar and ``info`` for the info section. :param info_sep: the separator between multiple info items (eta etc.) :param width: the width of the progress bar in characters, 0 means full terminal width :param file: the file to write to. If this is not a terminal then only the label is printed. :param color: controls if the terminal supports ANSI colors or not. The default is autodetection. This is only needed if ANSI codes are included anywhere in the progress bar output which is not the case by default. """ from ._termui_impl import ProgressBar color = resolve_color_default(color) return ProgressBar( iterable=iterable, length=length, show_eta=show_eta, show_percent=show_percent, show_pos=show_pos, item_show_func=item_show_func, fill_char=fill_char, empty_char=empty_char, bar_template=bar_template, info_sep=info_sep, file=file, label=label, width=width, color=color, )
[docs]def clear(): """Clears the terminal screen. This will have the effect of clearing the whole visible space of the terminal and moving the cursor to the top left. This does not do anything if not connected to a terminal. .. versionadded:: 2.0 """ if not isatty(sys.stdout): return # If we're on Windows and we don't have colorama available, then we # clear the screen by shelling out. Otherwise we can use an escape # sequence. if WIN: os.system("cls") else: sys.stdout.write("\033[2J\033[1;1H")
[docs]def style( text, fg=None, bg=None, bold=None, dim=None, underline=None, blink=None, reverse=None, reset=True, ): """Styles a text with ANSI styles and returns the new string. By default the styling is self contained which means that at the end of the string a reset code is issued. This can be prevented by passing ``reset=False``. Examples:: click.echo(click.style('Hello World!', fg='green')) click.echo(click.style('ATTENTION!', blink=True)) click.echo(click.style('Some things', reverse=True, fg='cyan')) Supported color names: * ``black`` (might be a gray) * ``red`` * ``green`` * ``yellow`` (might be an orange) * ``blue`` * ``magenta`` * ``cyan`` * ``white`` (might be light gray) * ``bright_black`` * ``bright_red`` * ``bright_green`` * ``bright_yellow`` * ``bright_blue`` * ``bright_magenta`` * ``bright_cyan`` * ``bright_white`` * ``reset`` (reset the color code only) .. versionadded:: 2.0 .. versionadded:: 7.0 Added support for bright colors. :param text: the string to style with ansi codes. :param fg: if provided this will become the foreground color. :param bg: if provided this will become the background color. :param bold: if provided this will enable or disable bold mode. :param dim: if provided this will enable or disable dim mode. This is badly supported. :param underline: if provided this will enable or disable underline. :param blink: if provided this will enable or disable blinking. :param reverse: if provided this will enable or disable inverse rendering (foreground becomes background and the other way round). :param reset: by default a reset-all code is added at the end of the string which means that styles do not carry over. This can be disabled to compose styles. """ bits = [] if fg: try: bits.append("\033[{}m".format(_ansi_colors[fg])) except KeyError: raise TypeError("Unknown color '{}'".format(fg)) if bg: try: bits.append("\033[{}m".format(_ansi_colors[bg] + 10)) except KeyError: raise TypeError("Unknown color '{}'".format(bg)) if bold is not None: bits.append("\033[{}m".format(1 if bold else 22)) if dim is not None: bits.append("\033[{}m".format(2 if dim else 22)) if underline is not None: bits.append("\033[{}m".format(4 if underline else 24)) if blink is not None: bits.append("\033[{}m".format(5 if blink else 25)) if reverse is not None: bits.append("\033[{}m".format(7 if reverse else 27)) bits.append(text) if reset: bits.append(_ansi_reset_all) return "".join(bits)
[docs]def unstyle(text): """Removes ANSI styling information from a string. Usually it's not necessary to use this function as Click's echo function will automatically remove styling if necessary. .. versionadded:: 2.0 :param text: the text to remove style information from. """ return strip_ansi(text)
[docs]def secho(message=None, file=None, nl=True, err=False, color=None, **styles): """This function combines :func:`echo` and :func:`style` into one call. As such the following two calls are the same:: click.secho('Hello World!', fg='green') click.echo(click.style('Hello World!', fg='green')) All keyword arguments are forwarded to the underlying functions depending on which one they go with. .. versionadded:: 2.0 """ if message is not None: message = style(message, **styles) return echo(message, file=file, nl=nl, err=err, color=color)
[docs]def edit( text=None, editor=None, env=None, require_save=True, extension=".txt", filename=None ): r"""Edits the given text in the defined editor. If an editor is given (should be the full path to the executable but the regular operating system search path is used for finding the executable) it overrides the detected editor. Optionally, some environment variables can be used. If the editor is closed without changes, `None` is returned. In case a file is edited directly the return value is always `None` and `require_save` and `extension` are ignored. If the editor cannot be opened a :exc:`UsageError` is raised. Note for Windows: to simplify cross-platform usage, the newlines are automatically converted from POSIX to Windows and vice versa. As such, the message here will have ``\n`` as newline markers. :param text: the text to edit. :param editor: optionally the editor to use. Defaults to automatic detection. :param env: environment variables to forward to the editor. :param require_save: if this is true, then not saving in the editor will make the return value become `None`. :param extension: the extension to tell the editor about. This defaults to `.txt` but changing this might change syntax highlighting. :param filename: if provided it will edit this file instead of the provided text contents. It will not use a temporary file as an indirection in that case. """ from ._termui_impl import Editor editor = Editor( editor=editor, env=env, require_save=require_save, extension=extension ) if filename is None: return editor.edit(text) editor.edit_file(filename)
[docs]def launch(url, wait=False, locate=False): """This function launches the given URL (or filename) in the default viewer application for this file type. If this is an executable, it might launch the executable in a new session. The return value is the exit code of the launched application. Usually, ``0`` indicates success. Examples:: click.launch('https://click.palletsprojects.com/') click.launch('/my/downloaded/file', locate=True) .. versionadded:: 2.0 :param url: URL or filename of the thing to launch. :param wait: waits for the program to stop. :param locate: if this is set to `True` then instead of launching the application associated with the URL it will attempt to launch a file manager with the file located. This might have weird effects if the URL does not point to the filesystem. """ from ._termui_impl import open_url return open_url(url, wait=wait, locate=locate)
# If this is provided, getchar() calls into this instead. This is used # for unittesting purposes. _getchar = None
[docs]def getchar(echo=False): """Fetches a single character from the terminal and returns it. This will always return a unicode character and under certain rare circumstances this might return more than one character. The situations which more than one character is returned is when for whatever reason multiple characters end up in the terminal buffer or standard input was not actually a terminal. Note that this will always read from the terminal, even if something is piped into the standard input. Note for Windows: in rare cases when typing non-ASCII characters, this function might wait for a second character and then return both at once. This is because certain Unicode characters look like special-key markers. .. versionadded:: 2.0 :param echo: if set to `True`, the character read will also show up on the terminal. The default is to not show it. """ f = _getchar if f is None: from ._termui_impl import getchar as f return f(echo)
def raw_terminal(): from ._termui_impl import raw_terminal as f return f()
[docs]def pause(info="Press any key to continue ...", err=False): """This command stops execution and waits for the user to press any key to continue. This is similar to the Windows batch "pause" command. If the program is not run through a terminal, this command will instead do nothing. .. versionadded:: 2.0 .. versionadded:: 4.0 Added the `err` parameter. :param info: the info string to print before pausing. :param err: if set to message goes to ``stderr`` instead of ``stdout``, the same as with echo. """ if not isatty(sys.stdin) or not isatty(sys.stdout): return try: if info: echo(info, nl=False, err=err) try: getchar() except (KeyboardInterrupt, EOFError): pass finally: if info: echo(err=err)