Loading bar

loading_bar.py

#!/usr/bin/env python
# encoding: utf-8

import os
import sys
import fcntl
import struct
import termios
import threading
from time import sleep


def getTerminalSize():
    """
    Returns (width, height) of your current terminal.
    """

    def ioctl_GWINSZ(fd):
        try:
            cr = struct.unpack('hh', fcntl.ioctl(fd, termios.TIOCGWINSZ,
        '1234'))
        except:
            return None
        return cr

    cr = ioctl_GWINSZ(0) or ioctl_GWINSZ(1) or ioctl_GWINSZ(2)

    if not cr:
        try:
            fd = os.open(os.ctermid(), os.O_RDONLY)
            cr = ioctl_GWINSZ(fd)
            os.close(fd)
        except:
            pass
    if not cr:
        try:
            cr = (env['LINES'], env['COLUMNS'])
        except:
            cr = (25, 80)
    return int(cr[1]), int(cr[0])


class ProgressBar(threading.Thread):
    """
    Displays a progress bar.
    """

    def __init__(self, total_items, message="Loading...", width=None):
        threading.Thread.__init__(self)

        self.total = total_items
        self.processed = 0
        self.message = message
        self.spin = u"|/—\\"
        self.spin_index = 0
        self.delay = 0.08

        if not width:
            self.fixed_width = False
        else:
            self.fixed_width = True
            self.width = width

    def progress(self):
        """
        Progress one step.
        """

        self.processed += 1

    def run(self):
        """
        Main loop.
        """

        stop = False

        while not stop:
            self.spin_index = (self.spin_index + 1) % len(self.spin)

            if not self.fixed_width:
                self.width = getTerminalSize()[0] - 35

            perc = 100.0 * self.processed / self.total
            completed = self.width * self.processed / self.total
            bar = "#" * completed + " " * (self.width - completed)

            result_data = (self.message, bar, perc, self.processed,
                           self.total, self.spin[self.spin_index])
            sys.stdout.write("\r%s [%s] %.2f%% (%d/%d) %s" % result_data)

            if self.processed == self.total:
                stop = True
                print

            sys.stdout.flush()
            sleep(self.delay)


if __name__ == "__main__":
    from random import random

    total = 35
    p = ProgressBar(total)
    p.start()

    for i in range(total):
        p.progress()
        sleep(random() / 2)