loading_bar.py

import sys
import time
from threading import RLock


_loading_bar_lock = RLock()
_loading_bar_default_width = 50
_loading_bar_width = 0
_loading_bar_start_time = 0
_loading_bar_count = 0
_loading_bar_total = 0
_loading_bar_reset_str = '\x1b[A\x1b[2K\x1b[G'
_loading_bar_fmt_str = ''

def loading_bar_init(total, width=_loading_bar_default_width):
    """
    Initializes the loading bar.
    Arguments:
        total: The total amount of items that will be processed
        width: The width of the loading bar
    """
    with _loading_bar_lock:
        global _loading_bar_width, _loading_bar_start_time, _loading_bar_count, _loading_bar_total, _loading_bar_fmt_str
        _loading_bar_width = width
        _loading_bar_start_time = time.time()
        _loading_bar_count = 0
        _loading_bar_total = total
        total_str_len = len(str(_loading_bar_total))
        _loading_bar_fmt_str = _loading_bar_reset_str + '[{: <'+str(_loading_bar_width)+'s}] {:7.2%} {:'+str(total_str_len + ((total_str_len - 1) // 3))+',d}/{:,d}  Elapsed: {:s} Remaining: {:s}\n'
        sys.stdout.write('\n' + _loading_bar_fmt_str.format(' ' * _loading_bar_width, 0.0, 0, _loading_bar_total, _format_time(0), _format_time(0)))
        # sys.stdout.flush()

def _format_time(time):
    return '{:d}:{:02d}:{:02d}'.format(int(time / 60.0 / 60.0), int(time / 60.0 % 60.0), int(time % 60.0))

def loading_bar_update():
    """
    Updates the loading bar.
    """
    with _loading_bar_lock:
        global _loading_bar_width, _loading_bar_start_time, _loading_bar_count, _loading_bar_total, _loading_bar_fmt_str
        _loading_bar_count += 1
        progress = float(_loading_bar_count) / _loading_bar_total
        bars = int(_loading_bar_width * progress)
        curr_time = time.time()
        time_elapsed = curr_time - _loading_bar_start_time
        time_remaining = time_elapsed / progress - time_elapsed
        sys.stdout.write(_loading_bar_fmt_str.format('=' * bars, progress, _loading_bar_count, _loading_bar_total, _format_time(time_elapsed), _format_time(time_remaining)))
        # sys.stdout.flush()

def loading_bar_finish():
    """
    Cleans up the loading bar.
    """
    with _loading_bar_lock:
        global _loading_bar_width, _loading_bar_start_time, _loading_bar_count, _loading_bar_total, _loading_bar_fmt_str
        curr_time = time.time()
        time_elapsed = curr_time - _loading_bar_start_time
        sys.stdout.write(_loading_bar_fmt_str.format('=' * _loading_bar_width, 1.0, _loading_bar_total, _loading_bar_total, _format_time(time_elapsed), _format_time(0)) + '\a')
        # sys.stdout.flush()