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# -*- coding: utf-8 -*- # # progressbar - Text progress bar library for Python. # Copyright (c) 2005 Nilton Volpato # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2.1 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
except ImportError: pass
"""The ProgressBar class which updates and prints the bar.
A common way of using it is like: >>> pbar = ProgressBar().start() >>> for i in range(100): ... # do something ... pbar.update(i+1) ... >>> pbar.finish()
You can also use a ProgressBar as an iterator: >>> progress = ProgressBar() >>> for i in progress(some_iterable): ... # do something ...
Since the progress bar is incredibly customizable you can specify different widgets of any type in any order. You can even write your own widgets! However, since there are already a good number of widgets you should probably play around with them before moving on to create your own widgets.
The term_width parameter represents the current terminal width. If the parameter is set to an integer then the progress bar will use that, otherwise it will attempt to determine the terminal width falling back to 80 columns if the width cannot be determined.
When implementing a widget's update method you are passed a reference to the current progress bar. As a result, you have access to the ProgressBar's methods and attributes. Although there is nothing preventing you from changing the ProgressBar you should treat it as read only.
Useful methods and attributes include (Public API): - currval: current progress (0 <= currval <= maxval) - maxval: maximum (and final) value - finished: True if the bar has finished (reached 100%) - start_time: the time when start() method of ProgressBar was called - seconds_elapsed: seconds elapsed since start_time and last call to update - percentage(): progress in percent [0..100] """
'left_justify', 'maxval', 'next_update', 'num_intervals', 'poll', 'seconds_elapsed', 'signal_set', 'start_time', 'term_width', 'update_interval', 'widgets', '_time_sensitive', '__iterable')
left_justify=True, fd=None): """Initializes a progress bar with sane defaults."""
# Don't share a reference with any other progress bars if widgets is None: widgets = list(self._DEFAULT_WIDGETS)
self.maxval = maxval self.widgets = widgets self.fd = fd if fd is not None else sys.stderr self.left_justify = left_justify
self.signal_set = False if term_width is not None: self.term_width = term_width else: try: self._handle_resize() signal.signal(signal.SIGWINCH, self._handle_resize) self.signal_set = True except (SystemExit, KeyboardInterrupt): raise except: self.term_width = self._env_size()
self.__iterable = None self._update_widgets() self.currval = 0 self.finished = False self.last_update_time = None self.poll = poll self.seconds_elapsed = 0 self.start_time = None self.update_interval = 1 self.next_update = 0
"""Use a ProgressBar to iterate through an iterable."""
try: self.maxval = len(iterable) except: if self.maxval is None: self.maxval = widgets.UnknownLength
self.__iterable = iter(iterable) return self
return self
try: value = next(self.__iterable) if self.start_time is None: self.start() else: self.update(self.currval + 1) return value except StopIteration: if self.start_time is None: self.start() self.finish() raise
# Create an alias so that Python 2.x won't complain about not being # an iterator.
"""Tries to find the term_width from the environment."""
return int(os.environ.get('COLUMNS', self._DEFAULT_TERMSIZE)) - 1
"""Tries to catch resize signals sent from the terminal."""
h, w = array('h', ioctl(self.fd, termios.TIOCGWINSZ, '\0' * 8))[:2] self.term_width = w
"""Returns the progress as a percentage.""" if self.maxval is widgets.UnknownLength: return float("NaN") if self.currval >= self.maxval: return 100.0 return (self.currval * 100.0 / self.maxval) if self.maxval else 100.00
result = [] expanding = [] width = self.term_width
for index, widget in enumerate(self.widgets): if isinstance(widget, widgets.WidgetHFill): result.append(widget) expanding.insert(0, index) else: widget = widgets.format_updatable(widget, self) result.append(widget) width -= len(widget)
count = len(expanding) while count: portion = max(int(math.ceil(width * 1. / count)), 0) index = expanding.pop() count -= 1
widget = result[index].update(self, portion) width -= len(widget) result[index] = widget
return result
"""Joins the widgets and justifies the line."""
widgets = ''.join(self._format_widgets())
if self.left_justify: return widgets.ljust(self.term_width) else: return widgets.rjust(self.term_width)
"""Returns whether the ProgressBar should redraw the line.""" if self.currval >= self.next_update or self.finished: return True
delta = time.time() - self.last_update_time return self._time_sensitive and delta > self.poll
"""Checks all widgets for the time sensitive bit."""
self._time_sensitive = any(getattr(w, 'TIME_SENSITIVE', False) for w in self.widgets)
"""Updates the ProgressBar to a new value."""
if value is not None and value is not widgets.UnknownLength: if (self.maxval is not widgets.UnknownLength and not 0 <= value <= self.maxval):
raise ValueError('Value out of range')
self.currval = value
if not self._need_update(): return if self.start_time is None: raise RuntimeError('You must call "start" before calling "update"')
now = time.time() self.seconds_elapsed = now - self.start_time self.next_update = self.currval + self.update_interval self.fd.write(self._format_line() + '\r') self.fd.flush() self.last_update_time = now
"""Starts measuring time, and prints the bar at 0%.
It returns self so you can use it like this: >>> pbar = ProgressBar().start() >>> for i in range(100): ... # do something ... pbar.update(i+1) ... >>> pbar.finish() """
if self.maxval is None: self.maxval = self._DEFAULT_MAXVAL
self.num_intervals = max(100, self.term_width) self.next_update = 0
if self.maxval is not widgets.UnknownLength: if self.maxval < 0: raise ValueError('Value out of range') self.update_interval = self.maxval / self.num_intervals
self.start_time = self.last_update_time = time.time() self.update(0)
return self
"""Puts the ProgressBar bar in the finished state."""
if self.finished: return self.finished = True self.update(self.maxval) self.fd.write('\n') if self.signal_set: signal.signal(signal.SIGWINCH, signal.SIG_DFL) |