class ProgressBar(object):
"""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]
"""
__slots__ = ('currval', 'fd', 'finished', 'last_update_time',
'left_justify', 'maxval', 'next_update', 'num_intervals',
'poll', 'seconds_elapsed', 'signal_set', 'start_time',
'term_width', 'update_interval', 'widgets', '_time_sensitive',
'__iterable')
_DEFAULT_MAXVAL = 100
_DEFAULT_TERMSIZE = 80
_DEFAULT_WIDGETS = [widgets.Percentage(), ' ', widgets.Bar()]
def __init__(self,
maxval=None,
widgets=None,
term_width=None,
poll=1,
left_justify=True,
fd=sys.stderr):
"""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
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
def __call__(self, iterable):
"""Use a ProgressBar to iterate through an iterable."""
try:
self.maxval = len(iterable)
except:
if self.maxval is None:
self.maxval = UnknownLength
self.__iterable = iter(iterable)
return self
def __iter__(self):
return self
def __next__(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.
next = __next__
def _env_size(self):
"""Tries to find the term_width from the environment."""
return int(os.environ.get('COLUMNS', self._DEFAULT_TERMSIZE)) - 1
def _handle_resize(self, signum=None, frame=None):
"""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
def percentage(self):
"""Returns the progress as a percentage."""
if self.currval >= self.maxval:
return 100.0
return self.currval * 100.0 / self.maxval
percent = property(percentage)
def _format_widgets(self):
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
def _format_line(self):
"""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)
def _need_update(self):
"""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
def _update_widgets(self):
"""Checks all widgets for the time sensitive bit."""
self._time_sensitive = any(
getattr(w, 'TIME_SENSITIVE', False) for w in self.widgets)
def update(self, value=None):
"""Updates the ProgressBar to a new value."""
if value is not None and value is not UnknownLength:
if (self.maxval is not 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
def start(self):
"""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 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
def finish(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)
class ProgressBar(object):
"""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]
"""
__slots__ = ('currval', 'fd', 'finished', 'last_update_time',
'left_justify', 'maxval', 'next_update', 'num_intervals',
'poll', 'seconds_elapsed', 'signal_set', 'start_time',
'term_width', 'update_interval', 'widgets', '_time_sensitive',
'__iterable', 'attr', 'html_written', 'uuid')
_DEFAULT_MAXVAL = 100
_DEFAULT_TERMSIZE = 80
_DEFAULT_WIDGETS = [widgets.Percentage(), ' ', widgets.Bar()]
def __init__(self, maxval=None, widgets=None, term_width=None, poll=1,
left_justify=True, fd=sys.stdout, attr={}):
"""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
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.attr = attr
# Set flag so we only write out the HTML once,
# then update with javascript
self.html_written = False
self.uuid = str(uuid.uuid4())
# Install our CSS if we are in an IPython notebook
if ipython == 'ipython-notebook':
from IPython.display import Javascript, display
display(Javascript('//%s\n$("head").append("<style>%s</style>")' %
(self.uuid,ipython_notebook_css)))
# Also add a function that removes progressbar output from the cells
js = '''
// %s -- used to remove this code blob in the end
IPython.OutputArea.prototype.cleanProgressBar = function(uuids) {
// filter by uuid-strings
var myfilter = function(output) {
var nuids = uuids.length;
for (var i=0; i<nuids; i++) {
if (output.hasOwnProperty('html')) {
if (output.html.indexOf(uuids[i]) != -1) {
return false;
}
}
if (output.hasOwnProperty('javascript')) {
if (output.javascript.indexOf(uuids[i]) != -1) {
return false;
}
}
}
// keep all others
return true;
};
// Filter the ouputs
this.outputs = this.outputs.filter(myfilter);
};
''' % self.uuid
display(Javascript(js))
def __call__(self, iterable):
"""Use a ProgressBar to iterate through an iterable."""
try:
self.maxval = len(iterable)
except:
if self.maxval is None:
self.maxval = UnknownLength
self.__iterable = iter(iterable)
return self
def __iter__(self):
return self
def __next__(self):
try:
value = next(self.__iterable)
if self.start_time is None: self.start()
else: self.update(self.currval + 1)
return value
except StopIteration:
self.finish()
raise
# Create an alias so that Python 2.x won't complain about not being
# an iterator.
next = __next__
def _env_size(self):
"""Tries to find the term_width from the environment."""
return int(os.environ.get('COLUMNS', self._DEFAULT_TERMSIZE)) - 1
def _handle_resize(self, signum=None, frame=None):
"""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
def percentage(self):
"""Returns the progress as a percentage."""
return self.currval * 100.0 / self.maxval
percent = property(percentage)
def _format_widgets(self):
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
def _format_line(self):
"""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)
def _format_html(self):
html = '<div class="pb" id="%s"><table class="pb ui-widget"><tr>\n' % self.uuid
for widget in self.widgets:
if isinstance(widget, widgets.WidgetHFill):
td_class = 'pb_widget_fill'
else:
td_class = 'pb_widget'
html += ('<td class="%s">' % td_class) + \
widgets.format_updatable_html(widget, self) + \
'</td>\n'
html += '</tr></table><div>'
return html
def _need_update(self):
"""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
def _update_widgets(self):
"""Checks all widgets for the time sensitive bit."""
self._time_sensitive = any(getattr(w, 'TIME_SENSITIVE', False)
for w in self.widgets)
def update(self, value=None, attr={}):
"""Updates the ProgressBar to a new value."""
if value is not None and value is not UnknownLength:
if (self.maxval is not UnknownLength
and not 0 <= value <= self.maxval):
raise ValueError('Value out of range')
self.currval = value
self.attr.update(attr)
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
if ipython == 'ipython-notebook':
if not self.html_written:
# We have yet to display the HTML, do that first
from IPython.display import HTML, display
display(HTML(self._format_html()))
self.html_written = True
else:
# The HTML has been written once, now update with JS
from IPython.display import Javascript, display
for widget in self.widgets:
js = widgets.updatable_js(widget, self)
if js:
display(Javascript(js))
else:
self.fd.write('\r' + self._format_line())
self.fd.flush()
self.last_update_time = now
def start(self):
"""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 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.html_written = False
self.finished = False
self.update(0)
return self
def finish(self):
"""Puts the ProgressBar bar in the finished state."""
self.finished = True
self.update(self.maxval)
self.start_time = None
# Clean up notebook stuff, quite differently from regular
if not ipython == 'ipython-notebook':
self.fd.write('\n')
else:
from IPython.display import Javascript, display
# First delete the node that held the progress bar from the page
js = """var element = document.getElementById('%s');
element.parentNode.removeChild(element);""" % self.uuid
display(Javascript(js))
# Then also remove its trace from the cell output (so it doesn't get
# stored with the notebook). This needs to be done for all widgets as
# well as for progressBar
uuids = [str(self.uuid)]
uuids += [w.uuid for w in self.widgets if isinstance(w, widgets.Widget)]
display(Javascript('this.cleanProgressBar(%s)' % uuids))
if self.signal_set:
signal.signal(signal.SIGWINCH, signal.SIG_DFL)