Source code for astropy.utils.console

# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Utilities for console input and output.
"""

import codecs
import locale
import math
import multiprocessing
import os
import re
import struct
import sys
import threading
import time

# concurrent.futures imports moved inside functions using them to avoid
# import failure when running in pyodide/Emscripten

try:
    import fcntl
    import signal
    import termios

    _CAN_RESIZE_TERMINAL = True
except ImportError:
    _CAN_RESIZE_TERMINAL = False

from astropy import conf

from .decorators import classproperty
from .misc import isiterable

__all__ = [
    "isatty",
    "color_print",
    "human_time",
    "human_file_size",
    "ProgressBar",
    "Spinner",
    "print_code_line",
    "ProgressBarOrSpinner",
    "terminal_size",
]

_DEFAULT_ENCODING = "utf-8"


class _IPython:
    """Singleton class given access to IPython streams, etc."""

    @classproperty
    def get_ipython(cls):
        try:
            from IPython import get_ipython
        except ImportError:
            pass
        return get_ipython

    @classproperty
    def OutStream(cls):
        if not hasattr(cls, "_OutStream"):
            cls._OutStream = None
            try:
                cls.get_ipython()
            except NameError:
                return None

            try:
                from ipykernel.iostream import OutStream
            except ImportError:
                try:
                    from IPython.zmq.iostream import OutStream
                except ImportError:
                    from IPython import version_info

                    if version_info[0] >= 4:
                        return None

                    try:
                        from IPython.kernel.zmq.iostream import OutStream
                    except ImportError:
                        return None

            cls._OutStream = OutStream

        return cls._OutStream

    @classproperty
    def ipyio(cls):
        if not hasattr(cls, "_ipyio"):
            try:
                from IPython.utils import io
            except ImportError:
                cls._ipyio = None
            else:
                cls._ipyio = io
        return cls._ipyio

    @classmethod
    def get_stream(cls, stream):
        return getattr(cls.ipyio, stream)


def _get_stdout(stderr=False):
    """
    This utility function contains the logic to determine what streams to use
    by default for standard out/err.

    Typically this will just return `sys.stdout`, but it contains additional
    logic for use in IPython on Windows to determine the correct stream to use
    (usually ``IPython.util.io.stdout`` but only if sys.stdout is a TTY).
    """

    if stderr:
        stream = "stderr"
    else:
        stream = "stdout"

    sys_stream = getattr(sys, stream)
    return sys_stream


[docs]def isatty(file): """ Returns `True` if ``file`` is a tty. Most built-in Python file-like objects have an `isatty` member, but some user-defined types may not, so this assumes those are not ttys. """ if ( multiprocessing.current_process().name != "MainProcess" or threading.current_thread().name != "MainThread" ): return False if hasattr(file, "isatty"): return file.isatty() if _IPython.OutStream is None or (not isinstance(file, _IPython.OutStream)): return False # File is an IPython OutStream. Check whether: # - File name is 'stdout'; or # - File wraps a Console if getattr(file, "name", None) == "stdout": return True if hasattr(file, "stream"): # FIXME: pyreadline has no had new release since 2015, drop it when # IPython minversion is 5.x. # On Windows, in IPython 2 the standard I/O streams will wrap # pyreadline.Console objects if pyreadline is available; this should # be considered a TTY. try: from pyreadline.console import Console as PyreadlineConsole except ImportError: return False return isinstance(file.stream, PyreadlineConsole) return False
[docs]def terminal_size(file=None): """ Returns a tuple (height, width) containing the height and width of the terminal. This function will look for the width in height in multiple areas before falling back on the width and height in astropy's configuration. """ if file is None: file = _get_stdout() try: s = struct.pack("HHHH", 0, 0, 0, 0) x = fcntl.ioctl(file, termios.TIOCGWINSZ, s) (lines, width, xpixels, ypixels) = struct.unpack("HHHH", x) if lines > 12: lines -= 6 if width > 10: width -= 1 if lines <= 0 or width <= 0: raise Exception("unable to get terminal size") return (lines, width) except Exception: try: # see if POSIX standard variables will work return (int(os.environ.get("LINES")), int(os.environ.get("COLUMNS"))) except TypeError: # fall back on configuration variables, or if not # set, (25, 80) lines = conf.max_lines width = conf.max_width if lines is None: lines = 25 if width is None: width = 80 return lines, width
def _color_text(text, color): """ Returns a string wrapped in ANSI color codes for coloring the text in a terminal:: colored_text = color_text('Here is a message', 'blue') This won't actually effect the text until it is printed to the terminal. Parameters ---------- text : str The string to return, bounded by the color codes. color : str An ANSI terminal color name. Must be one of: black, red, green, brown, blue, magenta, cyan, lightgrey, default, darkgrey, lightred, lightgreen, yellow, lightblue, lightmagenta, lightcyan, white, or '' (the empty string). """ color_mapping = { "black": "0;30", "red": "0;31", "green": "0;32", "brown": "0;33", "blue": "0;34", "magenta": "0;35", "cyan": "0;36", "lightgrey": "0;37", "default": "0;39", "darkgrey": "1;30", "lightred": "1;31", "lightgreen": "1;32", "yellow": "1;33", "lightblue": "1;34", "lightmagenta": "1;35", "lightcyan": "1;36", "white": "1;37", } if sys.platform == "win32" and _IPython.OutStream is None: # On Windows do not colorize text unless in IPython return text color_code = color_mapping.get(color, "0;39") return f"\033[{color_code}m{text}\033[0m" def _decode_preferred_encoding(s): """Decode the supplied byte string using the preferred encoding for the locale (`locale.getpreferredencoding`) or, if the default encoding is invalid, fall back first on utf-8, then on latin-1 if the message cannot be decoded with utf-8. """ enc = locale.getpreferredencoding() try: try: return s.decode(enc) except LookupError: enc = _DEFAULT_ENCODING return s.decode(enc) except UnicodeDecodeError: return s.decode("latin-1") def _write_with_fallback(s, write, fileobj): """Write the supplied string with the given write function like ``write(s)``, but use a writer for the locale's preferred encoding in case of a UnicodeEncodeError. Failing that attempt to write with 'utf-8' or 'latin-1'. """ try: write(s) return write except UnicodeEncodeError: # Let's try the next approach... pass enc = locale.getpreferredencoding() try: Writer = codecs.getwriter(enc) except LookupError: Writer = codecs.getwriter(_DEFAULT_ENCODING) f = Writer(fileobj) write = f.write try: write(s) return write except UnicodeEncodeError: Writer = codecs.getwriter("latin-1") f = Writer(fileobj) write = f.write # If this doesn't work let the exception bubble up; I'm out of ideas write(s) return write
[docs]def color_print(*args, end="\n", **kwargs): """ Prints colors and styles to the terminal uses ANSI escape sequences. :: color_print('This is the color ', 'default', 'GREEN', 'green') Parameters ---------- positional args : str The positional arguments come in pairs (*msg*, *color*), where *msg* is the string to display and *color* is the color to display it in. *color* is an ANSI terminal color name. Must be one of: black, red, green, brown, blue, magenta, cyan, lightgrey, default, darkgrey, lightred, lightgreen, yellow, lightblue, lightmagenta, lightcyan, white, or '' (the empty string). file : writable file-like, optional Where to write to. Defaults to `sys.stdout`. If file is not a tty (as determined by calling its `isatty` member, if one exists), no coloring will be included. end : str, optional The ending of the message. Defaults to ``\\n``. The end will be printed after resetting any color or font state. """ file = kwargs.get("file", _get_stdout()) write = file.write if isatty(file) and conf.use_color: for i in range(0, len(args), 2): msg = args[i] if i + 1 == len(args): color = "" else: color = args[i + 1] if color: msg = _color_text(msg, color) # Some file objects support writing unicode sensibly on some Python # versions; if this fails try creating a writer using the locale's # preferred encoding. If that fails too give up. write = _write_with_fallback(msg, write, file) write(end) else: for i in range(0, len(args), 2): msg = args[i] write(msg) write(end)
def strip_ansi_codes(s): """ Remove ANSI color codes from the string. """ return re.sub("\033\\[([0-9]+)(;[0-9]+)*m", "", s)
[docs]def human_time(seconds): """ Returns a human-friendly time string that is always exactly 6 characters long. Depending on the number of seconds given, can be one of:: 1w 3d 2d 4h 1h 5m 1m 4s 15s Will be in color if console coloring is turned on. Parameters ---------- seconds : int The number of seconds to represent Returns ------- time : str A human-friendly representation of the given number of seconds that is always exactly 6 characters. """ units = [ ("y", 60 * 60 * 24 * 7 * 52), ("w", 60 * 60 * 24 * 7), ("d", 60 * 60 * 24), ("h", 60 * 60), ("m", 60), ("s", 1), ] seconds = int(seconds) if seconds < 60: return f" {seconds:2d}s" for i in range(len(units) - 1): unit1, limit1 = units[i] unit2, limit2 = units[i + 1] if seconds >= limit1: return "{:2d}{}{:2d}{}".format( seconds // limit1, unit1, (seconds % limit1) // limit2, unit2 ) return " ~inf"
[docs]def human_file_size(size): """ Returns a human-friendly string representing a file size that is 2-4 characters long. For example, depending on the number of bytes given, can be one of:: 256b 64k 1.1G Parameters ---------- size : int The size of the file (in bytes) Returns ------- size : str A human-friendly representation of the size of the file """ if hasattr(size, "unit"): # Import units only if necessary because the import takes a # significant time [#4649] from astropy import units as u size = u.Quantity(size, u.byte).value suffixes = " kMGTPEZY" if size == 0: num_scale = 0 else: num_scale = int(math.floor(math.log(size) / math.log(1000))) if num_scale > 7: suffix = "?" else: suffix = suffixes[num_scale] num_scale = int(math.pow(1000, num_scale)) value = size / num_scale str_value = str(value) if suffix == " ": str_value = str_value[: str_value.index(".")] elif str_value[2] == ".": str_value = str_value[:2] else: str_value = str_value[:3] return f"{str_value:>3s}{suffix}"
class _mapfunc: """ A function wrapper to support ProgressBar.map(). """ def __init__(self, func): self._func = func def __call__(self, i_arg): i, arg = i_arg return i, self._func(arg)
[docs]class ProgressBar: """ A class to display a progress bar in the terminal. It is designed to be used either with the ``with`` statement:: with ProgressBar(len(items)) as bar: for item in enumerate(items): bar.update() or as a generator:: for item in ProgressBar(items): item.process() """ def __init__(self, total_or_items, ipython_widget=False, file=None): """ Parameters ---------- total_or_items : int or sequence If an int, the number of increments in the process being tracked. If a sequence, the items to iterate over. ipython_widget : bool, optional If `True`, the progress bar will display as an IPython notebook widget. file : writable file-like, optional The file to write the progress bar to. Defaults to `sys.stdout`. If ``file`` is not a tty (as determined by calling its `isatty` member, if any, or special case hacks to detect the IPython console), the progress bar will be completely silent. """ if file is None: file = _get_stdout() if not ipython_widget and not isatty(file): self.update = self._silent_update self._silent = True else: self._silent = False if isiterable(total_or_items): self._items = iter(total_or_items) self._total = len(total_or_items) else: try: self._total = int(total_or_items) except TypeError: raise TypeError("First argument must be int or sequence") else: self._items = iter(range(self._total)) self._file = file self._start_time = time.time() self._human_total = human_file_size(self._total) self._ipython_widget = ipython_widget self._signal_set = False if not ipython_widget: self._should_handle_resize = _CAN_RESIZE_TERMINAL and self._file.isatty() self._handle_resize() if self._should_handle_resize: signal.signal(signal.SIGWINCH, self._handle_resize) self._signal_set = True self.update(0) def _handle_resize(self, signum=None, frame=None): terminal_width = terminal_size(self._file)[1] self._bar_length = terminal_width - 37 def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): if not self._silent: if exc_type is None: self.update(self._total) self._file.write("\n") self._file.flush() if self._signal_set: signal.signal(signal.SIGWINCH, signal.SIG_DFL) def __iter__(self): return self def __next__(self): try: rv = next(self._items) except StopIteration: self.__exit__(None, None, None) raise else: self.update() return rv
[docs] def update(self, value=None): """ Update progress bar via the console or notebook accordingly. """ # Update self.value if value is None: value = self._current_value + 1 self._current_value = value # Choose the appropriate environment if self._ipython_widget: self._update_ipython_widget(value) else: self._update_console(value)
def _update_console(self, value=None): """ Update the progress bar to the given value (out of the total given to the constructor). """ if self._total == 0: frac = 1.0 else: frac = float(value) / float(self._total) file = self._file write = file.write if frac > 1: bar_fill = int(self._bar_length) else: bar_fill = int(float(self._bar_length) * frac) write("\r|") color_print("=" * bar_fill, "blue", file=file, end="") if bar_fill < self._bar_length: color_print(">", "green", file=file, end="") write("-" * (self._bar_length - bar_fill - 1)) write("|") if value >= self._total: t = time.time() - self._start_time prefix = " " elif value <= 0: t = None prefix = "" else: t = ((time.time() - self._start_time) * (1.0 - frac)) / frac prefix = " ETA " write(f" {human_file_size(value):>4s}/{self._human_total:>4s}") write(f" ({frac:>6.2%})") write(prefix) if t is not None: write(human_time(t)) self._file.flush() def _update_ipython_widget(self, value=None): """ Update the progress bar to the given value (out of a total given to the constructor). This method is for use in the IPython notebook 2+. """ # Create and display an empty progress bar widget, # if none exists. if not hasattr(self, "_widget"): # Import only if an IPython widget, i.e., widget in iPython NB from IPython import version_info if version_info[0] < 4: from IPython.html import widgets self._widget = widgets.FloatProgressWidget() else: _IPython.get_ipython() from ipywidgets import widgets self._widget = widgets.FloatProgress() from IPython.display import display display(self._widget) self._widget.value = 0 # Calculate percent completion, and update progress bar frac = value / self._total self._widget.value = frac * 100 self._widget.description = f" ({frac:>6.2%})" def _silent_update(self, value=None): pass
[docs] @classmethod def map( cls, function, items, multiprocess=False, file=None, step=100, ipython_widget=False, multiprocessing_start_method=None, ): """Map function over items while displaying a progress bar with percentage complete. The map operation may run in arbitrary order on the items, but the results are returned in sequential order. :: def work(i): print(i) ProgressBar.map(work, range(50)) Parameters ---------- function : function Function to call for each step items : sequence Sequence where each element is a tuple of arguments to pass to *function*. multiprocess : bool, int, optional If `True`, use the `multiprocessing` module to distribute each task to a different processor core. If a number greater than 1, then use that number of cores. ipython_widget : bool, optional If `True`, the progress bar will display as an IPython notebook widget. file : writable file-like, optional The file to write the progress bar to. Defaults to `sys.stdout`. If ``file`` is not a tty (as determined by calling its `isatty` member, if any), the scrollbar will be completely silent. step : int, optional Update the progress bar at least every *step* steps (default: 100). If ``multiprocess`` is `True`, this will affect the size of the chunks of ``items`` that are submitted as separate tasks to the process pool. A large step size may make the job complete faster if ``items`` is very long. multiprocessing_start_method : str, optional Useful primarily for testing; if in doubt leave it as the default. When using multiprocessing, certain anomalies occur when starting processes with the "spawn" method (the only option on Windows); other anomalies occur with the "fork" method (the default on Linux). """ if multiprocess: function = _mapfunc(function) items = list(enumerate(items)) results = cls.map_unordered( function, items, multiprocess=multiprocess, file=file, step=step, ipython_widget=ipython_widget, multiprocessing_start_method=multiprocessing_start_method, ) if multiprocess: _, results = zip(*sorted(results)) results = list(results) return results
[docs] @classmethod def map_unordered( cls, function, items, multiprocess=False, file=None, step=100, ipython_widget=False, multiprocessing_start_method=None, ): """Map function over items, reporting the progress. Does a `map` operation while displaying a progress bar with percentage complete. The map operation may run on arbitrary order on the items, and the results may be returned in arbitrary order. :: def work(i): print(i) ProgressBar.map(work, range(50)) Parameters ---------- function : function Function to call for each step items : sequence Sequence where each element is a tuple of arguments to pass to *function*. multiprocess : bool, int, optional If `True`, use the `multiprocessing` module to distribute each task to a different processor core. If a number greater than 1, then use that number of cores. ipython_widget : bool, optional If `True`, the progress bar will display as an IPython notebook widget. file : writable file-like, optional The file to write the progress bar to. Defaults to `sys.stdout`. If ``file`` is not a tty (as determined by calling its `isatty` member, if any), the scrollbar will be completely silent. step : int, optional Update the progress bar at least every *step* steps (default: 100). If ``multiprocess`` is `True`, this will affect the size of the chunks of ``items`` that are submitted as separate tasks to the process pool. A large step size may make the job complete faster if ``items`` is very long. multiprocessing_start_method : str, optional Useful primarily for testing; if in doubt leave it as the default. When using multiprocessing, certain anomalies occur when starting processes with the "spawn" method (the only option on Windows); other anomalies occur with the "fork" method (the default on Linux). """ # concurrent.futures import here to avoid import failure when running # in pyodide/Emscripten from concurrent.futures import ProcessPoolExecutor, as_completed results = [] if file is None: file = _get_stdout() with cls(len(items), ipython_widget=ipython_widget, file=file) as bar: if bar._ipython_widget: chunksize = step else: default_step = max(int(float(len(items)) / bar._bar_length), 1) chunksize = min(default_step, step) if not multiprocess or multiprocess < 1: for i, item in enumerate(items): results.append(function(item)) if (i % chunksize) == 0: bar.update(i) else: ctx = multiprocessing.get_context(multiprocessing_start_method) kwargs = dict(mp_context=ctx) with ProcessPoolExecutor( max_workers=( int(multiprocess) if multiprocess is not True else None ), **kwargs, ) as p: for i, f in enumerate( as_completed(p.submit(function, item) for item in items) ): bar.update(i) results.append(f.result()) return results
[docs]class Spinner: """ A class to display a spinner in the terminal. It is designed to be used with the ``with`` statement:: with Spinner("Reticulating splines", "green") as s: for item in enumerate(items): s.update() """ _default_unicode_chars = "◓◑◒◐" _default_ascii_chars = "-/|\\" def __init__(self, msg, color="default", file=None, step=1, chars=None): """ Parameters ---------- msg : str The message to print color : str, optional An ANSI terminal color name. Must be one of: black, red, green, brown, blue, magenta, cyan, lightgrey, default, darkgrey, lightred, lightgreen, yellow, lightblue, lightmagenta, lightcyan, white. file : writable file-like, optional The file to write the spinner to. Defaults to `sys.stdout`. If ``file`` is not a tty (as determined by calling its `isatty` member, if any, or special case hacks to detect the IPython console), the spinner will be completely silent. step : int, optional Only update the spinner every *step* steps chars : str, optional The character sequence to use for the spinner """ if file is None: file = _get_stdout() self._msg = msg self._color = color self._file = file self._step = step if chars is None: if conf.unicode_output: chars = self._default_unicode_chars else: chars = self._default_ascii_chars self._chars = chars self._silent = not isatty(file) if self._silent: self._iter = self._silent_iterator() else: self._iter = self._iterator() def _iterator(self): chars = self._chars index = 0 file = self._file write = file.write flush = file.flush try_fallback = True while True: write("\r") color_print(self._msg, self._color, file=file, end="") write(" ") try: if try_fallback: write = _write_with_fallback(chars[index], write, file) else: write(chars[index]) except UnicodeError: # If even _write_with_fallback failed for any reason just give # up on trying to use the unicode characters chars = self._default_ascii_chars write(chars[index]) try_fallback = False # No good will come of using this again flush() yield for i in range(self._step): yield index = (index + 1) % len(chars) def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): file = self._file write = file.write flush = file.flush if not self._silent: write("\r") color_print(self._msg, self._color, file=file, end="") if exc_type is None: color_print(" [Done]", "green", file=file) else: color_print(" [Failed]", "red", file=file) flush() def __iter__(self): return self def __next__(self): next(self._iter)
[docs] def update(self, value=None): """Update the spin wheel in the terminal. Parameters ---------- value : int, optional Ignored (present just for compatibility with `ProgressBar.update`). """ next(self)
def _silent_iterator(self): color_print(self._msg, self._color, file=self._file, end="") self._file.flush() while True: yield
[docs]class ProgressBarOrSpinner: """ A class that displays either a `ProgressBar` or `Spinner` depending on whether the total size of the operation is known or not. It is designed to be used with the ``with`` statement:: if file.has_length(): length = file.get_length() else: length = None bytes_read = 0 with ProgressBarOrSpinner(length) as bar: while file.read(blocksize): bytes_read += blocksize bar.update(bytes_read) """ def __init__(self, total, msg, color="default", file=None): """ Parameters ---------- total : int or None If an int, the number of increments in the process being tracked and a `ProgressBar` is displayed. If `None`, a `Spinner` is displayed. msg : str The message to display above the `ProgressBar` or alongside the `Spinner`. color : str, optional The color of ``msg``, if any. Must be an ANSI terminal color name. Must be one of: black, red, green, brown, blue, magenta, cyan, lightgrey, default, darkgrey, lightred, lightgreen, yellow, lightblue, lightmagenta, lightcyan, white. file : writable file-like, optional The file to write the to. Defaults to `sys.stdout`. If ``file`` is not a tty (as determined by calling its `isatty` member, if any), only ``msg`` will be displayed: the `ProgressBar` or `Spinner` will be silent. """ if file is None: file = _get_stdout() if total is None or not isatty(file): self._is_spinner = True self._obj = Spinner(msg, color=color, file=file) else: self._is_spinner = False color_print(msg, color, file=file) self._obj = ProgressBar(total, file=file) def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): return self._obj.__exit__(exc_type, exc_value, traceback)
[docs] def update(self, value): """ Update the progress bar to the given value (out of the total given to the constructor. """ self._obj.update(value)
# The following four Getch* classes implement unbuffered character reading from # stdin on Windows, linux, MacOSX. This is taken directly from ActiveState # Code Recipes: # http://code.activestate.com/recipes/134892-getch-like-unbuffered-character-reading-from-stdin/ # class Getch: """Get a single character from standard input without screen echo. Returns ------- char : str (one character) """ def __init__(self): try: self.impl = _GetchWindows() except ImportError: try: self.impl = _GetchMacCarbon() except (ImportError, AttributeError): self.impl = _GetchUnix() def __call__(self): return self.impl() class _GetchUnix: def __init__(self): import sys # noqa: F401 # import termios now or else you'll get the Unix # version on the Mac import termios # noqa: F401 import tty # noqa: F401 def __call__(self): import sys import termios import tty fd = sys.stdin.fileno() old_settings = termios.tcgetattr(fd) try: tty.setraw(sys.stdin.fileno()) ch = sys.stdin.read(1) finally: termios.tcsetattr(fd, termios.TCSADRAIN, old_settings) return ch class _GetchWindows: def __init__(self): import msvcrt # noqa: F401 def __call__(self): import msvcrt return msvcrt.getch() class _GetchMacCarbon: """ A function which returns the current ASCII key that is down; if no ASCII key is down, the null string is returned. The page http://www.mactech.com/macintosh-c/chap02-1.html was very helpful in figuring out how to do this. """ def __init__(self): import Carbon Carbon.Evt # see if it has this (in Unix, it doesn't) def __call__(self): import Carbon if Carbon.Evt.EventAvail(0x0008)[0] == 0: # 0x0008 is the keyDownMask return "" else: # # The event contains the following info: # (what,msg,when,where,mod)=Carbon.Evt.GetNextEvent(0x0008)[1] # # The message (msg) contains the ASCII char which is # extracted with the 0x000000FF charCodeMask; this # number is converted to an ASCII character with chr() and # returned # (what, msg, when, where, mod) = Carbon.Evt.GetNextEvent(0x0008)[1] return chr(msg & 0x000000FF)