Function valid_and_norm_path

pywebio/platform/path_deploy.py:53–70

Join the sub-path to base path. This function always ensure the result path is a subpath of base path. :param str base: MUST a absolute path :param str subpath: sub-path under the `base` path :return: normalized result path. None returned if the sub path is not valid

(base, subpath)

def valid_and_norm_path(base, subpath):
    """Join the sub-path to base path. This function always ensure the result path is a subpath of base path.

    :param str base: MUST a absolute path
    :param str subpath: sub-path under the `base` path
    :return: normalized result path. None returned if the sub path is not valid
    """
    subpath = subpath.lstrip('/')
    full_path = os.path.normpath(os.path.join(base, subpath))
    if not full_path.startswith(base):
        return None

    parts = subpath.split('/')
    for i in parts:
        if not filename_ok(i):
            return None

    return full_path


_cached_modules = {}