Get download progress with boto3

progress.py

import sys
import threading

class ProgressPercentage(object):
  ''' Progress Class
  Class for calculating and displaying download progress
  '''

  def __init__(self, client, bucket, filename):
    ''' Initialize
    initialize with: file name, file size and lock.
    Set seen_so_far to 0. Set progress bar length
    '''
    self._filename = filename
    self._size = client.head_object(Bucket=bucket, Key=filename)['ContentLength']
    self._seen_so_far = 0
    self._lock = threading.Lock()
    self.prog_bar_len = 80

  def __call__(self, bytes_amount):
    ''' Call
    When called, increments seen_so_far by bytes_amount,
    calculates percentage of seen_so_far/total file size
    and prints progress bar.
    '''
    # To simplify we'll assume this is hooked up to a single filename.
    with self._lock:
      self._seen_so_far += bytes_amount
      ratio = round((float(self._seen_so_far) / float(self._size)) * (self.prog_bar_len - 6), 1)
      current_length = int(round(ratio))

      percentage = round(100 * ratio / (self.prog_bar_len - 6), 1)

      bars = '+' * current_length
      output = bars + ' ' * (self.prog_bar_len - current_length - len(str(percentage)) - 1) + str(percentage) + '%'

      if self._seen_so_far != self._size:
        sys.stdout.write(output + '\r')
      else:
        sys.stdout.write(output + '\n')
      sys.stdout.flush()
      
      
s3 = boto3.client('s3')
progress = ProgressPercentage(s3, bucket, f'{model_name}.tar.gz')
s3.download_file(bucket, f'{model_name}.tar.gz', f'{model_name}.tar.gz', Callback=progress)