[FIXED] How to copy a file in Python with a progress bar?

Issue

When copying large files using shutil.copy(), you get no indication of how the operation is progressing..

I have put together something that works - it uses a simple ProgressBar class (which simple returns a simple ASCII progress bar, as a string), and a loop of open().read() and .write() to do the actual copying. It displays the progress bar using sys.stdout.write("\r%s\r" % (the_progress_bar)) which is a little hackish, but it works.

You can see the code (in context) on github here

Is there any built-in module that will do this better? Is there any improvements that can be made to this code?

Solution

Two things:

• I would make the default block size a lot larger than 512. I would start with 16384 and perhaps more.
• For modularity, it might be better to have the copy_with_prog function not output the progress bar itself, but call a callback function so the caller can decide how to display the progress.

Perhaps something like this:

def copy_with_prog(src, dest, callback = None):
    while True:
        # copy loop stuff
        if callback:
            callback(pos, total)

prog = ProgressBar(...)
copy_with_prog(src, dest, lambda pos, total: prog.update(pos, total))

Answered By - Greg Hewgill