Add support to an user defined progress bar inside download function.

[jcfaracco]

This commit just introduces a new argument to the download function: bar. The argument let the person who is developing code define his own progress bar using whatever he wants to. It also requires the pattern of passing the current size of the file and the total size.

An external function should be defined like

def my_progress_bar(cur, total):
    print(cur, total)

And then used as:

gdown.download(id=id, bar=my_progress_bar)

Signed-off-by: Julio Faracco [email protected]

[wkentaro]

Can make bar as the same api as tqdm.tqdm? and rename it to pbar in the argument?

[jcfaracco]

Hi @wkentaro. Do you mean have the attributes update and close like tqdm or just a function with one parameter?

[wkentaro]

Hi @jcfaracco. Yeah, I don't mind dropping tqdm if there is an ultimate API to support pbar as function argument.
I wonder how the other libraries are doing this.

[jcfaracco]

If we analyze progress, we can see a similar approach to tqdm but using different function names. Again, I'm not proposing to drop tqdm, just the ability to use a user-defined pbar. For example, mine is a ipywidget that unfortunately does not work well with tqdm :-( I would love to use gdown with my widget. :-)

[wkentaro]

Thanks for the example of progress. To understand more deeply about your needs, can you give me a short snippet of how you want to use with ipywidget?

[jcfaracco]

Sure @wkentaro

This is some simple example

import threading

from IPython import display as disp
from ipywidgets import HBox, FloatProgress, Label

class NotebookProgressBar(threading.Thread):
    MIN_CUR = -2
    MIN_TOTAL = -1

    def __init__(self):
        threading.Thread.__init__(self)

        self.bar = None
        self.percentage = None
        self.data = None

        self.__lock = threading.Lock()
        self.__current = self.MIN_CUR
        self.__total = self.MIN_TOTAL
        self.__error = False

    def show(self):
        self.bar = FloatProgress(value=0, min=0, max=100)
        self.percentage = Label(value='0 %')
        self.data = Label(value='')
        box = HBox((self.percentage, self.bar, self.data))
        disp.display(box)

    def set_current(self, current, total):
        with self.__lock:
            self.__current = current
            self.__total = total

    def set_error(self, error):
        self.__error = error

    def run(self):
        while (not self.__error and self.__current < self.__total):
            time.sleep(1)

            if self.__current != self.MIN_CUR and self.__total != self.MIN_TOTAL:
                progress = (self.__current / self.__total) * 100
                self.bar.value = progress
                self.percentage.value = f"{int(self.bar.value)} %%"
                self.data.value = f"{int(self.__current)} / {int(self.__total)}"

        if not self.__error:
            self.bar.style.bar_color = '#03c04a'
        else:
            self.bar.style.bar_color = '#ff0000'

All I need to do is update the bar with set_current() method. I usually use with wget, but this module does not work properly with Google Files for obvious reasons.