api_config_manager.py 文件源码

def _to_safe_path_param_name(matched_parameter):
    """Creates a safe string to be used as a regex group name.

    Only alphanumeric characters and underscore are allowed in variable name
    tokens, and numeric are not allowed as the first character.

    We cast the matched_parameter to base32 (since the alphabet is safe),
    strip the padding (= not safe) and prepend with _, since we know a token
    can begin with underscore.

    Args:
      matched_parameter: A string containing the parameter matched from the URL
        template.

    Returns:
      A string that's safe to be used as a regex group name.
    """
    return '_' + base64.b32encode(matched_parameter).rstrip('=')