def _send_chunk(self, start):
"""Send a chunk of the stream.
Helper for :meth:`stream_file`:
:type start: integer
:param start: start byte of the range.
:rtype: :class:`google.cloud.streaming.http_wrapper.Response`
:returns: The response from the chunked upload request.
"""
self._ensure_initialized()
no_log_body = self.total_size is None
if self.total_size is None:
# For the streaming resumable case, we need to detect when
# we're at the end of the stream.
body_stream = BufferedStream(
self.stream, start, self.chunksize)
end = body_stream.stream_end_position
if body_stream.stream_exhausted:
self._total_size = end
# Here, change body_stream from a stream to a string object,
# which means reading a chunk into memory. This works around
# https://code.google.com/p/httplib2/issues/detail?id=176 which can
# cause httplib2 to skip bytes on 401's for file objects.
body_stream = body_stream.read(self.chunksize)
else:
end = min(start + self.chunksize, self.total_size)
body_stream = StreamSlice(self.stream, end - start)
request = Request(url=self.url, http_method='PUT', body=body_stream)
request.headers['Content-Type'] = self.mime_type
if no_log_body:
# Disable logging of streaming body.
request.loggable_body = '<media body>'
if self.total_size is None:
# Streaming resumable upload case, unknown total size.
range_string = 'bytes %s-%s/*' % (start, end - 1)
elif end == start:
# End of an upload with 0 bytes left to send; just finalize.
range_string = 'bytes */%s' % self.total_size
else:
# Normal resumable upload case with known sizes.
range_string = 'bytes %s-%s/%s' % (start, end - 1, self.total_size)
request.headers['Content-Range'] = range_string
return self._send_media_request(request, end)
