http.py 文件源码

def _should_retry_response(resp_status, content):
  """Determines whether a response should be retried.

  Args:
    resp_status: The response status received.
    content: The response content body. 

  Returns:
    True if the response should be retried, otherwise False.
  """
  # Retry on 5xx errors.
  if resp_status >= 500:
    return True

  # Retry on 429 errors.
  if resp_status == _TOO_MANY_REQUESTS:
    return True

  # For 403 errors, we have to check for the `reason` in the response to
  # determine if we should retry.
  if resp_status == six.moves.http_client.FORBIDDEN:
    # If there's no details about the 403 type, don't retry.
    if not content:
      return False

    # Content is in JSON format.
    try:
      data = json.loads(content.decode('utf-8'))
      reason = data['error']['errors'][0]['reason']
    except (UnicodeDecodeError, ValueError, KeyError):
      LOGGER.warning('Invalid JSON content from response: %s', content)
      return False

    LOGGER.warning('Encountered 403 Forbidden with reason "%s"', reason)

    # Only retry on rate limit related failures.
    if reason in ('userRateLimitExceeded', 'rateLimitExceeded', ):
      return True

  # Everything else is a success or non-retriable so break.
  return False