Suggestion for rich/examples/downloader.py to handle keyboard interrupt

[pdc1]

Hello,

I love the rich library and was able to make a nice multithreaded ffmpeg wrapper with progress using the downloader.py example. However, I found it did not handle keyboard interrupts, at least on Windows.

With the following changes to the threadpool, it handles keyboard interrupts. Please consider incorporating something similar in the example. Thanks!

Original:

    with progress:
        with ThreadPoolExecutor(max_workers=4) as pool:
            for url in urls:
                filename = url.split("/")[-1]
                dest_path = os.path.join(dest_dir, filename)
                task_id = progress.add_task("download", filename=filename, start=False)
                pool.submit(copy_url, task_id, url, dest_path)

Updated:

    with progress
        with ThreadPoolExecutor(max_workers=4) as pool:
            tasks = []
            for url in urls:
                filename = url.split("/")[-1]
                dest_path = os.path.join(dest_dir, filename)
                task_id = progress.add_task("download", filename=filename, start=False)
                tasks.append(pool.submit(copy_url, task_id, url, dest_path))
            pending = tasks
            while pending:
                _, pending = wait(tasks, timeout=1, return_when=FIRST_EXCEPTION)
                if done_event.is_set():
                    pool.shutdown(wait=True, cancel_futures=True)
                    break

I also found the signal handling could be removed with the following change to the while/wait loop instead:

        try:
            while pending:
                _, pending = wait(tasks, timeout=1, return_when=FIRST_EXCEPTION)
        except KeyboardInterrupt:
            done_event.set()
            pool.shutdown(wait=True, cancel_futures=True)