flux.progress module

class flux.progress.Bottombar(formatter=None, **kwargs)

Bases: object

Maintain a status line at bottom of terminal using vt100 escape codes

The Bottombar class implements a very simple status line which stays positioned at the last line of vt100 capable terminals through the use of vt100 escape codes.

This class will only work properly on vt100 compatible terminals, which includes xterm, rxvt, and gnome-terminal and their derivatives on Linux, as well as iTerm and Terminal on OSX, and reportedly the new Windows Terminal on Windows.

Use of Bottombar requires that a formatter function be provided. The formatter will be called on each update as:

formatter(bbar, width)

Where bbar is the bottombar object being formatted and width is the current terminal width at the time of the update. The default formatter will simply print all extra

As a convenience, the Bottombar constructor collects all extra keyword arguments and presents them as attributes on the Bottombar object for later access from within and outside the provided formatter, e.g:

def formatter(bb, width):
    text = f"iteration={bb.i}"
    return text + time.ctime().rjust(width - len(text))

bb = Bottombar(formatter, i=0).start()
for i in range(0, 128):

will print a statusbar with an iteration count left justified, and the current time right justified.


The elapsed time since bb.start() in floating point seconds. As a convenience, bb.elapsed may be converted to a datetime.timedelta object via the dt attribute, e.g. bb.elapsed.dt.



  • formatter (function) -- Function which returns the status string

  • kwargs -- all extra keyword arguments are collected in the Bottombar instance and made available as attributes for convenience


Redraw bar without update


Start drawing a Bottombar


Reset terminal and write final bottombar state with newline


Update keyword args and redraw a bottombar

class flux.progress.ElapsedTime(x=0, /)

Bases: float

An ElapsedTime object is a floating point elapsed time in seconds that comes with a convenient "dt" property that returns a datetime.timedelta object

property dt
class flux.progress.ProgressBar(total=100, style='vertbars', before='', after=' {percent:5.1f}%', autostop=False, **kwargs)

Bases: Bottombar

Simple progress bar that stays on last line of terminal

The ProgressBar class uses the features of Bottombar to create a progress bar, plus optional other text, which stays on the last line of a terminal. A vt100 compatible terminal is required.

  • total (int) -- The total expected number of items/units for which the progressbar is monitoring progress, default=100.

  • style (str, optional) -- A string progress bar style from the list "line", "bar", "dots", "steps", "vertbars".

  • before (str, optional) -- A string to place before the progress bar.

  • after (str, optional) -- A string to place after the progress bar. default=" {percent:5.1f}%"

  • autostop (bool, optional) -- If True, ProgressBar instance will be automatically stopped when count == total. Otherwise, terminal reset will be deferred to an atexit handler.

  • kwargs (optional) -- Extra keyword args are saved and passed as args when formatting the before and after strings.

The before and after strings are formatted on each update to the progressbar and passed all extra keyword args, plus the current total, count, percent, and elapsed time e.g.:

before_str = before.format(

which means that these strings are most useful when they are format strings, e.g.:

ProgressBar(before="Running {total} jobs, {percent}% complete: ")
bar_style = {'bar': '─█', 'dots': '⣀⣄⣤⣦⣶⣷⣿', 'line': '─━', 'steps': ' ▁▂▃▄▅▆▇█', 'vertbars': ' ▏▎▍▌▋▊▉█'}
update(advance=1, **kwargs)

Update the state of a ProgressBar

Update the state of a ProgressBar and redraw if the progress bar is currently running. If count == total and autostop is set, the progress bar will be automatically stopped.

When the progress bar is stopped, the terminal will be reset and the final state of the bar will be left on the last line of output.

  • advance (int, optional) -- Advance progress by advance amount.

  • kwargs -- Update stored keyword arguments