embedding.py 文件源码

def ensure_file(name, url=None, force=False, logger=logging.getLogger(), postprocess=None):
        """
        Ensures that the file requested exists in the cache, downloading it if it does not exist.

        Args:
            name (str): name of the file.
            url (str): url to download the file from, if it doesn't exist.
            force (bool): whether to force the download, regardless of the existence of the file.
            logger (logging.Logger): logger to log results.
            postprocess (function): a function that, if given, will be applied after the file is downloaded. The function has the signature ``f(fname)``

        Returns:
            str: file name of the downloaded file.

        """
        fname = Embedding.path(name)
        if not path.isfile(fname) or force:
            if url:
                logger.critical('Downloading from {} to {}'.format(url, fname))
                Embedding.download_file(url, fname)
                if postprocess:
                    postprocess(fname)
            else:
                raise Exception('{} does not exist!'.format(fname))
        return fname