Source code for progressbar.widgets

#!/usr/bin/python
# -*- 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

'''Default ProgressBar widgets'''

from __future__ import division, absolute_import, with_statement

import datetime
import math
import abc


[docs]class AbstractWidget(object): __metaclass__ = abc.ABCMeta
[docs]def format_updatable(updatable, pbar): if hasattr(updatable, 'update'): return updatable.update(pbar) else: return updatable
[docs]class Widget(AbstractWidget):
'''The base class for all widgets The ProgressBar will call the widget's update value when the widget should be updated. The widget's size may change between calls, but the widget may display incorrectly if the size changes drastically and repeatedly. The boolean TIME_SENSITIVE informs the ProgressBar that it should be updated more often because it is time sensitive. ''' TIME_SENSITIVE = False @abc.abstractmethod def update(self, pbar): '''Updates the widget. pbar - a reference to the calling ProgressBar '''
[docs]class WidgetHFill(Widget):
'''The base class for all variable width widgets. This widget is much like the \\hfill command in TeX, it will expand to fill the line. You can use more than one in the same line, and they will all have the same width, and together will fill the line. ''' @abc.abstractmethod def update(self, pbar, width): '''Updates the widget providing the total width the widget must fill. pbar - a reference to the calling ProgressBar width - The total width the widget must fill '''
[docs]class Timer(Widget):
'Widget which displays the elapsed seconds.' TIME_SENSITIVE = True def __init__(self, format='Elapsed Time: %s'): self.format = format @staticmethod def format_time(seconds): 'Formats time as the string "HH:MM:SS".' return str(datetime.timedelta(seconds=int(seconds))) def update(self, pbar): 'Updates the widget to show the elapsed time.' return self.format % self.format_time(pbar.seconds_elapsed)
[docs]class ETA(Timer):
'Widget which attempts to estimate the time of arrival.' TIME_SENSITIVE = True def _eta(self, pbar): elapsed = pbar.seconds_elapsed return elapsed * pbar.maxval / pbar.currval - elapsed def update(self, pbar): 'Updates the widget to show the ETA or total time when finished.' if pbar.currval == 0: return 'ETA: --:--:--' elif pbar.finished: return 'Time: %s' % self.format_time(pbar.seconds_elapsed) else: return 'ETA: %s' % self.format_time(self._eta(pbar))
[docs]class AdaptiveETA(ETA): '''Widget which attempts to estimate the time of arrival. Uses a sampled average of the speed based on the 10 last updates. Very convenient for resuming the progress halfway. ''' TIME_SENSITIVE = True def __init__(self, num_samples=10): ETA.__init__(self) self.num_samples = num_samples self.samples = [] self.sample_vals = [] self.last_sample_val = None def _eta(self, pbar): samples = self.samples sample_vals = self.sample_vals if pbar.currval != self.last_sample_val: # Update the last sample counter, we only update if currval has # changed self.last_sample_val = pbar.currval # Add a sample but limit the size to `num_samples` samples.append(pbar.seconds_elapsed) sample_vals.append(pbar.currval) if len(samples) > self.num_samples: samples.pop(0) sample_vals.pop(0) if len(samples) <= 1: # No samples so just return the normal ETA calculation return ETA._eta(self, pbar) todo = pbar.maxval - pbar.currval items = sample_vals[-1] - sample_vals[0] duration = float(samples[-1] - samples[0]) per_item = duration / items return todo * per_item
[docs]class FileTransferSpeed(Widget):
'Widget for showing the transfer speed (useful for file transfers).' format = '%6.2f %s%s/s' prefixes = ' kMGTPEZY' def __init__(self, unit='B'): self.unit = unit def _speed(self, pbar): speed = pbar.currval / pbar.seconds_elapsed power = int(math.log(speed, 1000)) scaled = speed / 1000. ** power return scaled, power def update(self, pbar): 'Updates the widget with the current SI prefixed speed.' if pbar.seconds_elapsed < 2e-6 or pbar.currval < 2e-6: # =~ 0 scaled = power = 0 else: scaled, power = self._speed(pbar) return self.format % (scaled, self.prefixes[power], self.unit)
[docs]class AdaptiveTransferSpeed(FileTransferSpeed):
'Widget for showing the transfer speed, based on the last X samples' def __init__(self, num_samples=10): FileTransferSpeed.__init__(self) self.num_samples = num_samples self.samples = [] self.sample_vals = [] self.last_sample_val = None def _speed(self, pbar): samples = self.samples sample_vals = self.sample_vals if pbar.currval != self.last_sample_val: # Update the last sample counter, we only update if currval has # changed self.last_sample_val = pbar.currval # Add a sample but limit the size to `num_samples` samples.append(pbar.seconds_elapsed) sample_vals.append(pbar.currval) if len(samples) > self.num_samples: samples.pop(0) sample_vals.pop(0) if len(samples) <= 1: # No samples so just return the parent's calculation return FileTransferSpeed._speed(self, pbar) items = sample_vals[-1] - sample_vals[0] duration = float(samples[-1] - samples[0]) speed = items / duration power = int(math.log(speed, 1000)) scaled = speed / 1000. ** power return scaled, power
[docs]class AnimatedMarker(Widget):
'''An animated marker for the progress bar which defaults to appear as if it were rotating. ''' def __init__(self, markers='|/-\\'): self.markers = markers self.curmark = -1 def update(self, pbar): '''Updates the widget to show the next marker or the first marker when finished''' if pbar.finished: return self.markers[0] self.curmark = (self.curmark + 1) % len(self.markers) return self.markers[self.curmark] # Alias for backwards compatibility RotatingMarker = AnimatedMarker
[docs]class Counter(Widget):
'Displays the current count' def __init__(self, format='%d'): self.format = format def update(self, pbar): return self.format % pbar.currval
[docs]class Percentage(Widget):
'Displays the current percentage as a number with a percent sign.' def update(self, pbar): return '%3d%%' % pbar.percentage()
[docs]class FormatLabel(Timer):
'Displays a formatted label' mapping = { 'elapsed': ('seconds_elapsed', Timer.format_time), 'finished': ('finished', None), 'last_update': ('last_update_time', None), 'max': ('maxval', None), 'seconds': ('seconds_elapsed', None), 'start': ('start_time', None), 'value': ('currval', None) } def __init__(self, format): self.format = format def update(self, pbar): context = {} for name, (key, transform) in self.mapping.items(): try: value = getattr(pbar, key) if transform is None: context[name] = value else: context[name] = transform(value) except: # pragma: no cover pass return self.format % context
[docs]class SimpleProgress(Widget):
'Returns progress as a count of the total (e.g.: "5 of 47")' def __init__(self, sep=' of '): self.sep = sep def update(self, pbar): return '%d%s%d' % (pbar.currval, self.sep, pbar.maxval)
[docs]class Bar(WidgetHFill):
'A progress bar which stretches to fill the line.' def __init__(self, marker='#', left='|', right='|', fill=' ', fill_left=True): '''Creates a customizable progress bar. marker - string or updatable object to use as a marker left - string or updatable object to use as a left border right - string or updatable object to use as a right border fill - character to use for the empty part of the progress bar fill_left - whether to fill from the left or the right ''' self.marker = marker self.left = left self.right = right self.fill = fill self.fill_left = fill_left def update(self, pbar, width): 'Updates the progress bar and its subcomponents' left, marked, right = (format_updatable(i, pbar) for i in (self.left, self.marker, self.right)) width -= len(left) + len(right) # Marked must *always* have length of 1 if pbar.maxval: marked *= int(pbar.currval / pbar.maxval * width) else: # pragma: no cover marked = '' if self.fill_left: return '%s%s%s' % (left, marked.ljust(width, self.fill), right) else: return '%s%s%s' % (left, marked.rjust(width, self.fill), right)
[docs]class ReverseBar(Bar):
'A bar which has a marker which bounces from side to side.' def __init__(self, marker='#', left='|', right='|', fill=' ', fill_left=False): '''Creates a customizable progress bar. marker - string or updatable object to use as a marker left - string or updatable object to use as a left border right - string or updatable object to use as a right border fill - character to use for the empty part of the progress bar fill_left - whether to fill from the left or the right ''' self.marker = marker self.left = left self.right = right self.fill = fill self.fill_left = fill_left
[docs]class BouncingBar(Bar):
def update(self, pbar, width): 'Updates the progress bar and its subcomponents' left, marker, right = (format_updatable(i, pbar) for i in (self.left, self.marker, self.right)) width -= len(left) + len(right) if pbar.finished: return '%s%s%s' % (left, width * marker, right) position = int(pbar.currval % (width * 2 - 1)) if position > width: position = width * 2 - position lpad = self.fill * (position - 1) rpad = self.fill * (width - len(marker) - len(lpad)) # Swap if we want to bounce the other way if not self.fill_left: rpad, lpad = lpad, rpad return '%s%s%s%s%s' % (left, lpad, marker, rpad, right)