def download_requests_stream(request_stream,
destination,
message=None,
total_read=0):
"""This is a facility to download a request with nice progress bars."""
# Doing len(request_stream.content) may defeat the purpose of a
# progress bar
total_length = 0
if not request_stream.headers.get("Content-Encoding", ""):
total_length = int(request_stream.headers.get("Content-Length", "0"))
# Content-Length in the case of resuming will be
# Content-Length - total_read so we add back up to have the feel of
# resuming
if os.path.exists(destination):
total_length += total_read
progress_bar = _init_progress_bar(total_length, destination, message)
progress_bar.start()
if os.path.exists(destination):
mode = "ab"
else:
mode = "wb"
with open(destination, mode) as destination_file:
for buf in request_stream.iter_content(1024):
destination_file.write(buf)
if not is_dumb_terminal():
total_read += len(buf)
progress_bar.update(total_read)
progress_bar.finish()
def _init_progress_bar(total_length, destination, message=None):
if not message:
message = "Downloading {!r}".format(os.path.basename(destination))
valid_length = total_length and total_length > 0
if valid_length and is_dumb_terminal():
widgets = [message, " ", Percentage()]
maxval = total_length
elif valid_length and not is_dumb_terminal():
widgets = [
message,
Bar(marker="=", left="[", right="]"), " ",
Percentage()
]
maxval = total_length
elif not valid_length and is_dumb_terminal():
widgets = [message]
maxval = UnknownLength
else:
widgets = [message, AnimatedMarker()]
maxval = UnknownLength
return ProgressBar(widgets=widgets, maxval=maxval)