Source code for progressbar

#!/usr/bin/python
# -*- coding: iso-8859-1 -*-
#
# progressbar  - Text progressbar 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

"""
   **Module information** :

   Text progressbar library for python.

   This library provides a text mode progressbar. This is tipically used
   to  display  the progress  of  a  long running operation, providing a
   visual clue that processing is underway.

   The ProgressBar  class  manages  the progress, and  the format of the
   line is given by  a number of widgets. A widget is an object that may
   display differently depending on the state of the progress.

   There are three types of widget:

   - a string, which always shows itself;
   - a ProgressBarWidget, which may return a different value every time
     its update method is called; and
   - a ProgressBarWidgetHFill,  which is like ProgressBarWidget, except
     it expands to fill the remaining width of the line.

   The progressbar  module  is very easy to use, yet  very powerful. And
   automatically supports features like auto-resizing when available.

"""

__author__ = "Nilton Volpato"
__author_email__ = "first-name dot last-name @ gmail.com"
__date__ = "2006-05-07"
__version__ = "2.2"

# Changelog
#
# 2006-05-07: v2.2 fixed bug in windows
# 2005-12-04: v2.1 autodetect terminal width, added start method
# 2005-12-04: v2.0 everything is now a widget (wow!)
# 2005-12-03: v1.0 rewrite using widgets
# 2005-06-02: v0.5 rewrite
# 2004-??-??: v0.1 first version


import sys, time
from array import array
try:
    from fcntl import ioctl
    import termios
except ImportError:
    pass
import signal

[docs]class ProgressBarWidget(object): """This is an element of ProgressBar formatting. The ProgressBar object will call it's update value when an update is needed. It's size may change between call, but the results will not be good if the size changes drastically and repeatedly. """
[docs] def update(self, pbar): """Returns the string representing the widget. The parameter pbar is a reference to the calling ProgressBar, where one can access attributes of the class for knowing how the update must be made. At least this function must be overriden.""" pass
[docs]class ProgressBarWidgetHFill(object): """This is a variable width element of ProgressBar formatting. The ProgressBar object will call it's update value, informing the width this object must the made. This is like TeX `\hfill`, 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. """
[docs] def update(self, pbar, width): """Returns the string representing the widget. The parameter pbar is a reference to the calling ProgressBar, where one can access attributes of the class for knowing how the update must be made. The parameter width is the total horizontal width the widget must have. At least this function must be overriden.""" pass
[docs]class ETA(ProgressBarWidget): "Widget for the Estimated Time of Arrival" def format_time(self, seconds): return time.strftime('%H:%M:%S', time.gmtime(seconds)) def update(self, pbar): if pbar.currval == 0: return 'ETA: --:--:--' elif pbar.finished: return 'Time: %s' % self.format_time(pbar.seconds_elapsed) else: elapsed = pbar.seconds_elapsed eta = elapsed * pbar.maxval / pbar.currval - elapsed return 'ETA: %s' % self.format_time(eta)
[docs]class FileTransferSpeed(ProgressBarWidget): "Widget for showing the transfer speed (useful for file transfers)." def __init__(self): self.fmt = '%6.2f %s' self.units = ['B','K','M','G','T','P'] def update(self, pbar): if pbar.seconds_elapsed < 2e-6:#== 0: bps = 0.0 else: bps = float(pbar.currval) / pbar.seconds_elapsed spd = bps for u in self.units: if spd < 1000: break spd /= 1000 return self.fmt % (spd, u+'/s')
[docs]class RotatingMarker(ProgressBarWidget): "A rotating marker for filling the bar of progress." def __init__(self, markers='|/-\\'): self.markers = markers self.curmark = -1 def update(self, pbar): if pbar.finished: return self.markers[0] self.curmark = (self.curmark + 1)%len(self.markers) return self.markers[self.curmark]
[docs]class Percentage(ProgressBarWidget): "Just the percentage done." def update(self, pbar): return '%3d%%' % pbar.percentage()
[docs]class Bar(ProgressBarWidgetHFill): "The bar of progress. It will strech to fill the line." def __init__(self, marker='#', left='|', right='|'): self.marker = marker self.left = left self.right = right def _format_marker(self, pbar): if isinstance(self.marker, (str, unicode)): return self.marker else: return self.marker.update(pbar) def update(self, pbar, width): percent = pbar.percentage() cwidth = width - len(self.left) - len(self.right) marked_width = int(percent * cwidth / 100) m = self._format_marker(pbar) bar = (self.left + (m*marked_width).ljust(cwidth) + self.right) return bar
[docs]class ReverseBar(Bar): "The reverse bar of progress, or bar of regress. :)" def update(self, pbar, width): percent = pbar.percentage() cwidth = width - len(self.left) - len(self.right) marked_width = int(percent * cwidth / 100) m = self._format_marker(pbar) bar = (self.left + (m*marked_width).rjust(cwidth) + self.right) return bar
default_widgets = [Percentage(), ' ', Bar()]
[docs]class ProgressBar(object): """This is the ProgressBar class, it updates and prints the bar. The term_width parameter may be an integer. Or None, in which case it will try to guess it, if it fails it will default to 80 columns. The simple use is like this: >>> pbar = ProgressBar().start() >>> for i in xrange(100): ... # do something ... pbar.update(i+1) ... >>> pbar.finish() But anything you want to do is possible (well, almost anything). You can supply different widgets of any type in any order. And you can even write your own widgets! There are many widgets already shipped and you should experiment with them. When implementing a widget update method you may access any attribute or function of the ProgressBar object calling the widget's update method. The most important attributes you would like to access are: - *currval* current value of the progress, 0 <= currval <= maxval - *maxval* maximum (and final) value of the progress - *finished* True if the bar is have finished (reached 100%), False o/w - *start_time* first time update() method of ProgressBar was called - *seconds_elapsed* seconds elapsed since start_time - *percentage()* percentage of the progress (this is a method) """ def __init__(self, maxval=100, widgets=default_widgets, term_width=None, fd=sys.stderr): assert maxval > 0 self.maxval = maxval self.widgets = widgets self.fd = fd self.signal_set = False if term_width is None: try: self.handle_resize(None,None) signal.signal(signal.SIGWINCH, self.handle_resize) self.signal_set = True except: self.term_width = 79 else: self.term_width = term_width self.currval = 0 self.finished = False self.prev_percentage = -1 self.start_time = None self.seconds_elapsed = 0 def handle_resize(self, signum, frame): h,w=array('h', ioctl(self.fd,termios.TIOCGWINSZ,'\0'*8))[:2] self.term_width = w
[docs] def percentage(self): "Returns the percentage of the progress." return self.currval*100.0 / self.maxval
def _format_widgets(self): r = [] hfill_inds = [] num_hfill = 0 currwidth = 0 for i, w in enumerate(self.widgets): if isinstance(w, ProgressBarWidgetHFill): r.append(w) hfill_inds.append(i) num_hfill += 1 elif isinstance(w, (str, unicode)): r.append(w) currwidth += len(w) else: weval = w.update(self) currwidth += len(weval) r.append(weval) for iw in hfill_inds: r[iw] = r[iw].update(self, (self.term_width-currwidth)/num_hfill) return r def _format_line(self): return ''.join(self._format_widgets()).ljust(self.term_width) def _need_update(self): return int(self.percentage()) != int(self.prev_percentage)
[docs] def update(self, value): "Updates the progress bar to a new value." assert 0 <= value <= self.maxval self.currval = value if not self._need_update() or self.finished: return if not self.start_time: self.start_time = time.time() self.seconds_elapsed = time.time() - self.start_time self.prev_percentage = self.percentage() if value != self.maxval: self.fd.write(self._format_line() + '\r') else: self.finished = True self.fd.write(self._format_line() + '\n')
[docs] def start(self): """Start measuring time, and prints the bar at 0%. It returns self so you can use it like this: >>> pbar = ProgressBar().start() >>> for i in xrange(100): ... # do something ... pbar.update(i+1) ... >>> pbar.finish() """ self.update(0) return self
[docs] def finish(self): """Used to tell the progress is finished.""" self.update(self.maxval) if self.signal_set: signal.signal(signal.SIGWINCH, signal.SIG_DFL)
if __name__=='__main__': import os