python-click/click/termui.py
2018-09-06 14:55:10 -04:00

603 lines
22 KiB
Python

import os
import sys
import struct
import inspect
import itertools
from ._compat import raw_input, text_type, string_types, \
isatty, strip_ansi, get_winterm_size, DEFAULT_COLUMNS, WIN
from .utils import echo
from .exceptions import Abort, UsageError
from .types import convert_type, Choice, Path
from .globals import resolve_color_default
# 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 += ' (' + ", ".join(map(str, type.choices)) + ')'
if default is not None and show_default:
prompt = '%s [%s]' % (prompt, default)
return prompt + suffix
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 = hide_input and hidden_prompt_func or 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: %s' % e.message, err=err)
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)
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,
default and 'Y/n' or '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
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])
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)
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 displayed. 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.
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)
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')
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[%dm' % (_ansi_colors[fg]))
except KeyError:
raise TypeError('Unknown color %r' % fg)
if bg:
try:
bits.append('\033[%dm' % (_ansi_colors[bg] + 10))
except KeyError:
raise TypeError('Unknown color %r' % bg)
if bold is not None:
bits.append('\033[%dm' % (1 if bold else 22))
if dim is not None:
bits.append('\033[%dm' % (2 if dim else 22))
if underline is not None:
bits.append('\033[%dm' % (4 if underline else 24))
if blink is not None:
bits.append('\033[%dm' % (5 if blink else 25))
if reverse is not None:
bits.append('\033[%dm' % (7 if reverse else 27))
bits.append(text)
if reset:
bits.append(_ansi_reset_all)
return ''.join(bits)
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)
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)
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)
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('http://click.pocoo.org/')
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
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.
.. 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()
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)